Merge branch 'main' into feat/desktop-private-dms

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/AcceptedGamesRegistry.kt

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+/**
+ * Global registry of accepted game IDs.
+ *
+ * This singleton ensures that accepted game state is shared across all ViewModel instances.
+ * Without this, different ViewModels (e.g., lobby vs game screen) would have separate
+ * acceptedGameIds sets, causing the game screen to incorrectly load as spectator.
+ */
+object AcceptedGamesRegistry {
+    private val acceptedGameIds = mutableSetOf<String>()
+    private val lock = Any()
+
+    fun markAsAccepted(gameId: String) {
+        synchronized(lock) {
+            acceptedGameIds.add(gameId)
+        }
+    }
+
+    fun wasAccepted(gameId: String): Boolean =
+        synchronized(lock) {
+            acceptedGameIds.contains(gameId)
+        }
+
+    fun clear() {
+        synchronized(lock) {
+            acceptedGameIds.clear()
+        }
+    }
+
+    /** Remove old entries - call periodically to prevent memory leak */
+    fun clearOldEntries(keepGameIds: Set<String>) {
+        synchronized(lock) {
+            acceptedGameIds.retainAll(keepGameIds)
+        }
+    }
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/ChessBoard.kt

@@ -0,0 +1,146 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import androidx.compose.foundation.Image
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
+import com.vitorpamplona.quartz.nip64Chess.ChessPiece
+import com.vitorpamplona.quartz.nip64Chess.ChessPosition
+import com.vitorpamplona.quartz.nip64Chess.PieceType
+import com.vitorpamplona.quartz.nip64Chess.Color as ChessColor
+
+/**
+ * Renders an 8x8 chess board with pieces
+ * Shared composable for Android and Desktop platforms
+ *
+ * @param position The chess position to display
+ * @param modifier Modifier for the board
+ * @param boardSize Total size of the board in dp
+ * @param showCoordinates Whether to show file labels (a-h) on bottom rank
+ */
+@Composable
+fun ChessBoard(
+    position: ChessPosition,
+    modifier: Modifier = Modifier,
+    boardSize: Dp = 320.dp,
+    showCoordinates: Boolean = true,
+) {
+    val squareSize = boardSize / 8
+
+    Column(modifier = modifier.size(boardSize)) {
+        // Render ranks 8 down to 1 (from white's perspective)
+        for (rank in 7 downTo 0) {
+            Row {
+                for (file in 0..7) {
+                    val piece = position.pieceAt(file, rank)
+                    val isLightSquare = (rank + file) % 2 == 0
+
+                    ChessSquare(
+                        piece = piece,
+                        isLight = isLightSquare,
+                        size = squareSize,
+                        coordinate =
+                            if (showCoordinates && rank == 0) {
+                                ('a' + file).toString()
+                            } else {
+                                null
+                            },
+                    )
+                }
+            }
+        }
+    }
+}
+
+/**
+ * Renders a single square on the chess board
+ */
+@Composable
+private fun ChessSquare(
+    piece: com.vitorpamplona.quartz.nip64Chess.ChessPiece?,
+    isLight: Boolean,
+    size: Dp,
+    coordinate: String?,
+) {
+    Box(
+        modifier =
+            Modifier
+                .size(size)
+                .background(
+                    if (isLight) Color(0xFFF0D9B5) else Color(0xFFB58863),
+                ),
+        contentAlignment = Alignment.Center,
+    ) {
+        // Display piece using CBurnett ImageVector icons
+        piece?.let {
+            Image(
+                imageVector = it.toImageVector(),
+                contentDescription = "${it.color} ${it.type}",
+                modifier = Modifier.fillMaxSize().padding(2.dp),
+            )
+        }
+
+        // Show file coordinate (a-h) on bottom rank
+        coordinate?.let {
+            Text(
+                text = it,
+                fontSize = 10.sp,
+                fontWeight = FontWeight.Bold,
+                color = if (isLight) Color(0xFFB58863) else Color(0xFFF0D9B5),
+                modifier =
+                    Modifier
+                        .align(Alignment.BottomEnd)
+                        .padding(2.dp),
+            )
+        }
+    }
+}
+
+/**
+ * Extension function to convert ChessPiece to CBurnett ImageVector
+ */
+private fun ChessPiece.toImageVector(): ImageVector {
+    val white = color == ChessColor.WHITE
+    return when (type) {
+        PieceType.KING -> if (white) ChessPieceVectors.WhiteKing else ChessPieceVectors.BlackKing
+        PieceType.QUEEN -> if (white) ChessPieceVectors.WhiteQueen else ChessPieceVectors.BlackQueen
+        PieceType.ROOK -> if (white) ChessPieceVectors.WhiteRook else ChessPieceVectors.BlackRook
+        PieceType.BISHOP -> if (white) ChessPieceVectors.WhiteBishop else ChessPieceVectors.BlackBishop
+        PieceType.KNIGHT -> if (white) ChessPieceVectors.WhiteKnight else ChessPieceVectors.BlackKnight
+        PieceType.PAWN -> if (white) ChessPieceVectors.WhitePawn else ChessPieceVectors.BlackPawn
+    }
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/ChessBroadcastBanner.kt

@@ -0,0 +1,241 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import androidx.compose.animation.AnimatedVisibility
+import androidx.compose.animation.animateContentSize
+import androidx.compose.animation.core.animateFloatAsState
+import androidx.compose.animation.core.tween
+import androidx.compose.animation.fadeIn
+import androidx.compose.animation.fadeOut
+import androidx.compose.animation.slideInVertically
+import androidx.compose.animation.slideOutVertically
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.CheckCircle
+import androidx.compose.material.icons.filled.CloudSync
+import androidx.compose.material.icons.filled.Error
+import androidx.compose.material.icons.filled.HourglassBottom
+import androidx.compose.material.icons.filled.Sync
+import androidx.compose.material3.Icon
+import androidx.compose.material3.LinearProgressIndicator
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.unit.dp
+
+/**
+ * Shared banner showing chess broadcast status - broadcast progress, sync status, etc.
+ * Works on both Android and Desktop via Compose Multiplatform.
+ */
+@Composable
+fun ChessBroadcastBanner(
+    status: ChessBroadcastStatus,
+    onTap: () -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    val isVisible = status !is ChessBroadcastStatus.Idle
+
+    AnimatedVisibility(
+        visible = isVisible,
+        enter = slideInVertically(initialOffsetY = { -it }) + fadeIn(tween(200)),
+        exit = slideOutVertically(targetOffsetY = { -it }) + fadeOut(tween(150)),
+        modifier = modifier,
+    ) {
+        Surface(
+            color = getStatusBackgroundColor(status),
+            tonalElevation = 2.dp,
+            modifier =
+                Modifier
+                    .fillMaxWidth()
+                    .clickable(onClick = onTap),
+        ) {
+            Row(
+                verticalAlignment = Alignment.CenterVertically,
+                horizontalArrangement = Arrangement.spacedBy(8.dp),
+                modifier =
+                    Modifier
+                        .padding(horizontal = 16.dp, vertical = 8.dp)
+                        .animateContentSize(),
+            ) {
+                Icon(
+                    imageVector = getStatusIcon(status),
+                    contentDescription = null,
+                    tint = getStatusIconColor(status),
+                    modifier = Modifier.size(18.dp),
+                )
+
+                Column(modifier = Modifier.weight(1f)) {
+                    Row(
+                        horizontalArrangement = Arrangement.SpaceBetween,
+                        modifier = Modifier.fillMaxWidth(),
+                    ) {
+                        Text(
+                            text = getStatusText(status),
+                            style = MaterialTheme.typography.bodySmall,
+                            color = MaterialTheme.colorScheme.onSurface,
+                            maxLines = 1,
+                            overflow = TextOverflow.Ellipsis,
+                            modifier = Modifier.weight(1f),
+                        )
+
+                        Spacer(Modifier.width(8.dp))
+
+                        Text(
+                            text = getStatusDetail(status),
+                            style = MaterialTheme.typography.labelMedium,
+                            color = getStatusDetailColor(status),
+                        )
+                    }
+
+                    // Show progress bar for broadcasting/syncing
+                    val progress = getStatusProgress(status)
+                    if (progress != null) {
+                        Spacer(Modifier.height(4.dp))
+
+                        val animatedProgress by animateFloatAsState(
+                            targetValue = progress,
+                            animationSpec = tween(300),
+                            label = "progress",
+                        )
+
+                        LinearProgressIndicator(
+                            progress = { animatedProgress },
+                            modifier = Modifier.fillMaxWidth(),
+                            color = getStatusProgressColor(status),
+                            trackColor = MaterialTheme.colorScheme.surfaceVariant,
+                        )
+                    }
+                }
+            }
+        }
+    }
+}
+
+@Composable
+private fun getStatusBackgroundColor(status: ChessBroadcastStatus): Color =
+    when (status) {
+        is ChessBroadcastStatus.Failed, is ChessBroadcastStatus.Desynced -> {
+            MaterialTheme.colorScheme.errorContainer
+        }
+
+        is ChessBroadcastStatus.Success -> {
+            MaterialTheme.colorScheme.primaryContainer
+        }
+
+        else -> {
+            MaterialTheme.colorScheme.surfaceContainer
+        }
+    }
+
+private fun getStatusIcon(status: ChessBroadcastStatus): ImageVector =
+    when (status) {
+        is ChessBroadcastStatus.Broadcasting -> Icons.Default.Sync
+        is ChessBroadcastStatus.Success -> Icons.Default.CheckCircle
+        is ChessBroadcastStatus.Failed -> Icons.Default.Error
+        is ChessBroadcastStatus.WaitingForOpponent -> Icons.Default.HourglassBottom
+        is ChessBroadcastStatus.Syncing -> Icons.Default.CloudSync
+        is ChessBroadcastStatus.Desynced -> Icons.Default.Error
+        is ChessBroadcastStatus.Idle -> Icons.Default.CheckCircle
+    }
+
+@Composable
+private fun getStatusIconColor(status: ChessBroadcastStatus): Color =
+    when (status) {
+        is ChessBroadcastStatus.Failed, is ChessBroadcastStatus.Desynced -> {
+            MaterialTheme.colorScheme.error
+        }
+
+        is ChessBroadcastStatus.Success -> {
+            MaterialTheme.colorScheme.primary
+        }
+
+        is ChessBroadcastStatus.WaitingForOpponent -> {
+            MaterialTheme.colorScheme.secondary
+        }
+
+        else -> {
+            MaterialTheme.colorScheme.primary
+        }
+    }
+
+private fun getStatusText(status: ChessBroadcastStatus): String =
+    when (status) {
+        is ChessBroadcastStatus.Broadcasting -> "Broadcasting: ${status.san}"
+        is ChessBroadcastStatus.Success -> "Sent: ${status.san}"
+        is ChessBroadcastStatus.Failed -> "Failed: ${status.san}"
+        is ChessBroadcastStatus.WaitingForOpponent -> "Waiting for opponent's move..."
+        is ChessBroadcastStatus.Syncing -> "Syncing game state..."
+        is ChessBroadcastStatus.Desynced -> "Game desynced: ${status.message}"
+        is ChessBroadcastStatus.Idle -> ""
+    }
+
+private fun getStatusDetail(status: ChessBroadcastStatus): String =
+    when (status) {
+        is ChessBroadcastStatus.Broadcasting -> "[${status.successCount}/${status.totalRelays}]"
+        is ChessBroadcastStatus.Success -> "${status.relayCount} relays"
+        is ChessBroadcastStatus.Failed -> "Tap to retry"
+        is ChessBroadcastStatus.Syncing -> "${(status.progress * 100).toInt()}%"
+        is ChessBroadcastStatus.Desynced -> "Tap to resync"
+        else -> ""
+    }
+
+@Composable
+private fun getStatusDetailColor(status: ChessBroadcastStatus): Color =
+    when (status) {
+        is ChessBroadcastStatus.Failed, is ChessBroadcastStatus.Desynced -> {
+            MaterialTheme.colorScheme.error
+        }
+
+        else -> {
+            MaterialTheme.colorScheme.primary
+        }
+    }
+
+private fun getStatusProgress(status: ChessBroadcastStatus): Float? =
+    when (status) {
+        is ChessBroadcastStatus.Broadcasting -> status.progress
+        is ChessBroadcastStatus.Syncing -> status.progress
+        else -> null
+    }
+
+@Composable
+private fun getStatusProgressColor(status: ChessBroadcastStatus): Color =
+    when (status) {
+        is ChessBroadcastStatus.Failed -> MaterialTheme.colorScheme.error
+        else -> MaterialTheme.colorScheme.primary
+    }

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/ChessConfig.kt

@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+/**
+ * Global chess configuration shared across Android and Desktop.
+ *
+ * These relays are the primary relays used by Jester and other Nostr chess apps.
+ * Using a small, fixed set ensures fast queries and reliable game discovery.
+ */
+object ChessConfig {
+    /**
+     * The 3 main relays for chess events.
+     * These are used for both fetching and publishing chess events.
+     */
+    val CHESS_RELAYS =
+        listOf(
+            "wss://relay.damus.io",
+            "wss://nos.lol",
+            "wss://relay.primal.net",
+        )
+
+    /**
+     * Display names for the chess relays (without protocol prefix)
+     */
+    val CHESS_RELAY_NAMES =
+        listOf(
+            "relay.damus.io",
+            "nos.lol",
+            "relay.primal.net",
+        )
+
+    /**
+     * Timeout for relay queries in milliseconds.
+     * With only 3 relays, we can wait for all of them.
+     */
+    const val FETCH_TIMEOUT_MS = 10_000L
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/ChessEventCollector.kt

@@ -0,0 +1,266 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import com.vitorpamplona.quartz.nip01Core.core.Event
+import com.vitorpamplona.quartz.nip64Chess.JesterEvent
+import com.vitorpamplona.quartz.nip64Chess.JesterGameEvents
+import com.vitorpamplona.quartz.nip64Chess.JesterProtocol
+import com.vitorpamplona.quartz.nip64Chess.toJesterEvent
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import java.util.concurrent.ConcurrentHashMap
+
+/**
+ * Collects and aggregates Jester chess events for a game from any source.
+ *
+ * This class provides a unified way to collect events regardless of whether
+ * they come from LocalCache (Android), direct relay (Desktop), or test fixtures.
+ * It handles:
+ * - Deduplication by event ID
+ * - Thread-safe concurrent updates
+ * - Producing JesterGameEvents snapshots for reconstruction
+ *
+ * Jester Protocol:
+ * - All chess events use kind 30
+ * - Start events (content.kind=0) reference START_POSITION_HASH via e-tag
+ * - Move events (content.kind=1) reference [startEventId, headEventId] via e-tags
+ * - Full move history is included in every move event
+ *
+ * Usage:
+ * ```
+ * val collector = ChessEventCollector(startEventId)
+ *
+ * // Add events as they arrive from any source
+ * collector.addEvent(jesterEvent)
+ *
+ * // Get current state for reconstruction
+ * val events = collector.getEvents()
+ * val result = ChessStateReconstructor.reconstruct(events, viewerPubkey)
+ * ```
+ */
+class ChessEventCollector(
+    /** The start event ID - this is the game identifier in Jester protocol */
+    val startEventId: String,
+) {
+    // Start event (only one per game)
+    private val _startEvent = MutableStateFlow<JesterEvent?>(null)
+    val startEvent: StateFlow<JesterEvent?> = _startEvent.asStateFlow()
+
+    // Move events (deduplicated by event ID)
+    private val moves = ConcurrentHashMap<String, JesterEvent>()
+
+    // Track all processed event IDs for fast deduplication
+    private val processedEventIds = ConcurrentHashMap.newKeySet<String>()
+
+    // Flow that emits when any event is added (for reactive updates)
+    private val _eventCount = MutableStateFlow(0)
+    val eventCount: StateFlow<Int> = _eventCount.asStateFlow()
+
+    /**
+     * Check if an event has already been processed.
+     */
+    fun hasEvent(eventId: String): Boolean = processedEventIds.contains(eventId)
+
+    /**
+     * Add a Jester event for this game.
+     * Automatically categorizes as start or move based on content.kind.
+     *
+     * @return true if the event was added, false if already exists or invalid
+     */
+    fun addEvent(event: JesterEvent): Boolean {
+        if (processedEventIds.contains(event.id)) return false
+
+        // Check if this event belongs to our game
+        val eventStartId = event.startEventId()
+        val isStartEvent = event.isStartEvent() && event.id == startEventId
+        val isMoveEvent = event.isMoveEvent() && eventStartId == startEventId
+
+        if (!isStartEvent && !isMoveEvent) return false
+
+        return if (isStartEvent) {
+            addStartEvent(event)
+        } else {
+            addMoveEvent(event)
+        }
+    }
+
+    /**
+     * Add a raw Event if it's a valid Jester event for this game.
+     *
+     * @return true if the event was added, false if invalid or not for this game
+     */
+    fun addRawEvent(event: Event): Boolean {
+        if (event.kind != JesterProtocol.KIND) return false
+        val jesterEvent = event.toJesterEvent() ?: return false
+        return addEvent(jesterEvent)
+    }
+
+    /**
+     * Add the start event for this game.
+     * Only the first valid start is kept.
+     *
+     * @return true if the event was added, false if already exists or invalid
+     */
+    private fun addStartEvent(event: JesterEvent): Boolean {
+        if (processedEventIds.contains(event.id)) return false
+        if (!event.isStartEvent()) return false
+        if (event.id != startEventId) return false
+
+        if (_startEvent.compareAndSet(null, event)) {
+            processedEventIds.add(event.id)
+            incrementEventCount()
+            return true
+        }
+        return false
+    }
+
+    /**
+     * Add a move event for this game.
+     * Moves are deduplicated by event ID.
+     *
+     * @return true if the event was added, false if already exists or invalid
+     */
+    private fun addMoveEvent(event: JesterEvent): Boolean {
+        if (processedEventIds.contains(event.id)) return false
+        if (!event.isMoveEvent()) return false
+        if (event.startEventId() != startEventId) return false
+
+        if (moves.putIfAbsent(event.id, event) == null) {
+            processedEventIds.add(event.id)
+            incrementEventCount()
+            return true
+        }
+        return false
+    }
+
+    /**
+     * Get a snapshot of all collected events for reconstruction.
+     */
+    fun getEvents(): JesterGameEvents =
+        JesterGameEvents(
+            startEvent = _startEvent.value,
+            moves = moves.values.toList(),
+        )
+
+    /**
+     * Check if the game has a start event.
+     */
+    fun hasStartEvent(): Boolean = _startEvent.value != null
+
+    /**
+     * Check if the game has any moves (indicates game is active).
+     */
+    fun hasMoves(): Boolean = moves.isNotEmpty()
+
+    /**
+     * Check if the game has ended (has a move with result).
+     */
+    fun hasEnded(): Boolean = moves.values.any { it.result() != null }
+
+    /**
+     * Get the number of moves collected.
+     */
+    fun moveCount(): Int = moves.size
+
+    /**
+     * Get the latest move (with longest history).
+     */
+    fun latestMove(): JesterEvent? = moves.values.maxByOrNull { it.history().size }
+
+    /**
+     * Clear all collected events.
+     */
+    fun clear() {
+        _startEvent.value = null
+        moves.clear()
+        processedEventIds.clear()
+        _eventCount.value = 0
+    }
+
+    private fun incrementEventCount() {
+        _eventCount.value = processedEventIds.size
+    }
+}
+
+/**
+ * Manager for multiple game collectors.
+ *
+ * This is useful when managing multiple concurrent games,
+ * such as in a chess lobby or when spectating multiple games.
+ */
+class ChessEventCollectorManager {
+    private val collectors = ConcurrentHashMap<String, ChessEventCollector>()
+
+    /**
+     * Get or create a collector for a game.
+     *
+     * @param startEventId The start event ID (game identifier)
+     */
+    fun getOrCreate(startEventId: String): ChessEventCollector = collectors.getOrPut(startEventId) { ChessEventCollector(startEventId) }
+
+    /**
+     * Get a collector if it exists.
+     *
+     * @param startEventId The start event ID (game identifier)
+     */
+    fun get(startEventId: String): ChessEventCollector? = collectors[startEventId]
+
+    /**
+     * Remove a collector for a game.
+     *
+     * @param startEventId The start event ID (game identifier)
+     */
+    fun remove(startEventId: String): ChessEventCollector? = collectors.remove(startEventId)
+
+    /**
+     * Get all active game IDs (start event IDs).
+     */
+    fun activeGameIds(): Set<String> = collectors.keys.toSet()
+
+    /**
+     * Clear all collectors.
+     */
+    fun clear() {
+        collectors.values.forEach { it.clear() }
+        collectors.clear()
+    }
+
+    /**
+     * Add an event to the appropriate collector (auto-routing).
+     * Creates a collector if needed for start events.
+     *
+     * @return true if the event was added to a collector
+     */
+    fun addEvent(event: JesterEvent): Boolean {
+        // For start events, create collector with event ID
+        if (event.isStartEvent()) {
+            val collector = getOrCreate(event.id)
+            return collector.addEvent(event)
+        }
+
+        // For move events, find the collector by startEventId
+        val startId = event.startEventId() ?: return false
+        val collector = collectors[startId] ?: return false
+        return collector.addEvent(event)
+    }
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/ChessEventPolling.kt

@@ -0,0 +1,327 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.isActive
+import kotlinx.coroutines.launch
+
+/**
+ * Configuration for chess event polling
+ */
+data class ChessPollingConfig(
+    /** Interval for polling active games (ms) */
+    val activeGamePollInterval: Long = 10_000L,
+    /** Interval for polling challenges (ms) */
+    val challengePollInterval: Long = 30_000L,
+    /** Whether to continue polling in background */
+    val pollInBackground: Boolean = false,
+    /** Challenge expiry time (seconds) */
+    val challengeExpirySeconds: Long = 24 * 60 * 60L,
+    /** Cleanup interval (ms) */
+    val cleanupInterval: Long = 5 * 60 * 1000L,
+)
+
+/**
+ * Platform-specific defaults
+ */
+object ChessPollingDefaults {
+    /** Android: moderate intervals, no background polling */
+    val android =
+        ChessPollingConfig(
+            activeGamePollInterval = 5_000L, // 5 seconds for responsive gameplay
+            challengePollInterval = 15_000L, // 15 seconds for challenges
+            pollInBackground = false,
+        )
+
+    /** Desktop: fast polling for responsive gameplay */
+    val desktop =
+        ChessPollingConfig(
+            activeGamePollInterval = 2_000L, // 2 seconds for fast updates
+            challengePollInterval = 10_000L, // 10 seconds for challenges
+            pollInBackground = true,
+        )
+}
+
+/**
+ * Delegate for managing chess event polling
+ *
+ * Usage:
+ * ```
+ * class ChessViewModel(...) : ViewModel() {
+ *     private val pollingDelegate = ChessPollingDelegate(
+ *         config = ChessPollingDefaults.android,
+ *         scope = viewModelScope,
+ *         onRefreshGames = { gameIds -> refreshGamesFromCache(gameIds) },
+ *         onRefreshChallenges = { refreshChallengesFromCache() },
+ *     )
+ *
+ *     fun startPolling() = pollingDelegate.start()
+ *     fun stopPolling() = pollingDelegate.stop()
+ * }
+ * ```
+ */
+class ChessPollingDelegate(
+    private val config: ChessPollingConfig,
+    private val scope: CoroutineScope,
+    private val onRefreshGames: suspend (Set<String>) -> Unit,
+    private val onRefreshChallenges: suspend () -> Unit,
+    private val onCleanup: suspend () -> Unit = {},
+) {
+    private var gamePollingJob: Job? = null
+    private var challengePollingJob: Job? = null
+    private var cleanupJob: Job? = null
+    private var manualRefreshJob: Job? = null
+
+    private val _isPolling = MutableStateFlow(false)
+    val isPolling: StateFlow<Boolean> = _isPolling.asStateFlow()
+
+    private val _isRefreshing = MutableStateFlow(false)
+    val isRefreshing: StateFlow<Boolean> = _isRefreshing.asStateFlow()
+
+    internal val activeGameIdsFlow = MutableStateFlow<Set<String>>(emptySet())
+
+    /**
+     * Focused game ID - when set, only this game is polled for updates.
+     * Used when viewing a specific game screen to avoid refreshing unrelated games.
+     * When null, all games in activeGameIdsFlow are polled (lobby mode).
+     */
+    private val _focusedGameId = MutableStateFlow<String?>(null)
+
+    /**
+     * Set focused game mode - only poll this specific game.
+     * Call this when entering a game screen.
+     * Pass null to return to lobby mode (poll all games).
+     */
+    fun setFocusedGame(gameId: String?) {
+        _focusedGameId.value = gameId
+    }
+
+    /**
+     * Get current focused game ID (null = lobby mode, polls all games)
+     */
+    fun getFocusedGameId(): String? = _focusedGameId.value
+
+    /**
+     * Get the effective game IDs to poll based on focused mode.
+     * In focused mode: only the focused game.
+     * In lobby mode: all active games.
+     */
+    private fun getEffectiveGameIds(): Set<String> {
+        val focused = _focusedGameId.value
+        return if (focused != null) {
+            // Focused mode - only poll this game
+            setOf(focused)
+        } else {
+            // Lobby mode - poll all games
+            activeGameIdsFlow.value
+        }
+    }
+
+    /**
+     * Update the set of game IDs to poll for
+     */
+    fun setActiveGameIds(gameIds: Set<String>) {
+        activeGameIdsFlow.value = gameIds
+    }
+
+    /**
+     * Add a game ID to poll for
+     */
+    fun addGameId(gameId: String) {
+        activeGameIdsFlow.value = activeGameIdsFlow.value + gameId
+    }
+
+    /**
+     * Remove a game ID from polling
+     */
+    fun removeGameId(gameId: String) {
+        activeGameIdsFlow.value = activeGameIdsFlow.value - gameId
+    }
+
+    /**
+     * Start polling for chess events
+     */
+    fun start() {
+        if (_isPolling.value) {
+            return
+        }
+        _isPolling.value = true
+
+        // Poll for active games
+        gamePollingJob =
+            scope.launch {
+                while (isActive) {
+                    val gameIds = getEffectiveGameIds()
+                    if (gameIds.isNotEmpty()) {
+                        try {
+                            onRefreshGames(gameIds)
+                        } catch (_: Exception) {
+                            // Error during refresh - continue polling
+                        }
+                    }
+                    delay(config.activeGamePollInterval)
+                }
+            }
+
+        // Poll for challenges (only in lobby mode)
+        challengePollingJob =
+            scope.launch {
+                // Initial fetch (only if not in focused mode)
+                if (_focusedGameId.value == null) {
+                    onRefreshChallenges()
+                }
+
+                while (isActive) {
+                    delay(config.challengePollInterval)
+                    // Skip challenge polling in focused mode - game screen doesn't need it
+                    if (_focusedGameId.value == null) {
+                        onRefreshChallenges()
+                    }
+                }
+            }
+
+        // Cleanup job
+        cleanupJob =
+            scope.launch {
+                while (isActive) {
+                    delay(config.cleanupInterval)
+                    onCleanup()
+                }
+            }
+    }
+
+    /**
+     * Stop polling
+     */
+    fun stop() {
+        _isPolling.value = false
+        gamePollingJob?.cancel()
+        challengePollingJob?.cancel()
+        cleanupJob?.cancel()
+        gamePollingJob = null
+        challengePollingJob = null
+        cleanupJob = null
+    }
+
+    /**
+     * Pause polling (e.g., when app goes to background on Android)
+     */
+    fun pause() {
+        if (!config.pollInBackground) {
+            stop()
+        }
+    }
+
+    /**
+     * Resume polling (e.g., when app comes to foreground on Android)
+     */
+    fun resume() {
+        if (!_isPolling.value) {
+            start()
+        }
+    }
+
+    /**
+     * Force an immediate refresh (debounced - ignores calls if refresh already in progress)
+     */
+    fun refreshNow() {
+        // Debounce: skip if already refreshing
+        if (_isRefreshing.value) {
+            return
+        }
+
+        // Cancel any pending manual refresh
+        manualRefreshJob?.cancel()
+
+        manualRefreshJob =
+            scope.launch {
+                _isRefreshing.value = true
+                try {
+                    // In focused mode, skip challenge refresh (game screen doesn't need it)
+                    val focusedId = _focusedGameId.value
+                    if (focusedId == null) {
+                        onRefreshChallenges()
+                    }
+                    val gameIds = getEffectiveGameIds()
+                    if (gameIds.isNotEmpty()) {
+                        onRefreshGames(gameIds)
+                    }
+                } finally {
+                    _isRefreshing.value = false
+                }
+            }
+    }
+}
+
+/**
+ * Interface for chess event sources that can be refreshed
+ */
+interface ChessEventSource {
+    /**
+     * Fetch/refresh challenges from the event source
+     */
+    suspend fun fetchChallenges(): List<ChessChallengeData>
+
+    /**
+     * Fetch/refresh game state for specific game IDs
+     */
+    suspend fun fetchGameUpdates(gameIds: Set<String>): Map<String, ChessGameUpdate>
+}
+
+/**
+ * Data class representing a chess challenge
+ */
+data class ChessChallengeData(
+    val id: String,
+    val gameId: String,
+    val challengerPubkey: String,
+    val opponentPubkey: String?,
+    val challengerColor: com.vitorpamplona.quartz.nip64Chess.Color,
+    val createdAt: Long,
+    val isExpired: Boolean = false,
+)
+
+/**
+ * Data class representing a game update
+ */
+data class ChessGameUpdate(
+    val gameId: String,
+    val moves: List<ChessMoveData>,
+    val isEnded: Boolean = false,
+    val endReason: String? = null,
+)
+
+/**
+ * Data class representing a chess move
+ */
+data class ChessMoveData(
+    val san: String,
+    val fen: String,
+    val moveNumber: Int,
+    val playerPubkey: String,
+    val timestamp: Long,
+)

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/ChessGameLoader.kt

@@ -0,0 +1,182 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import com.vitorpamplona.quartz.nip64Chess.ChessEngine
+import com.vitorpamplona.quartz.nip64Chess.ChessStateReconstructor
+import com.vitorpamplona.quartz.nip64Chess.Color
+import com.vitorpamplona.quartz.nip64Chess.JesterGameEvents
+import com.vitorpamplona.quartz.nip64Chess.LiveChessGameState
+import com.vitorpamplona.quartz.nip64Chess.ReconstructedGameState
+import com.vitorpamplona.quartz.nip64Chess.ReconstructionResult
+import com.vitorpamplona.quartz.nip64Chess.ViewerRole
+
+/**
+ * Converts a ReconstructedGameState (from ChessStateReconstructor) into a
+ * LiveChessGameState (used by ViewModels for reactive updates).
+ *
+ * This bridges the gap between the deterministic reconstruction algorithm
+ * and the stateful game management that ViewModels need.
+ *
+ * Usage:
+ * ```
+ * // Collect events from any source
+ * val collector = ChessEventCollector(startEventId)
+ * collector.addEvent(startEvent)
+ * collector.addEvent(moveEvent1)
+ * collector.addEvent(moveEvent2)
+ *
+ * // Reconstruct using shared algorithm
+ * val result = ChessStateReconstructor.reconstruct(collector.getEvents(), viewerPubkey)
+ *
+ * // Convert to LiveChessGameState for ViewModel use
+ * val gameState = ChessGameLoader.toLiveGameState(result, viewerPubkey)
+ * ```
+ */
+object ChessGameLoader {
+    /**
+     * Convert a ReconstructionResult to a LiveChessGameState for ViewModel use.
+     *
+     * @param result The result from ChessStateReconstructor
+     * @param viewerPubkey The pubkey of the user viewing the game
+     * @return LiveChessGameState or null if reconstruction failed
+     */
+    fun toLiveGameState(
+        result: ReconstructionResult,
+        viewerPubkey: String,
+    ): LiveChessGameState? {
+        if (result !is ReconstructionResult.Success) return null
+
+        val state = result.state
+        val engine = result.engine
+
+        val (playerPubkey, opponentPubkey) =
+            when (state.viewerRole) {
+                ViewerRole.WHITE_PLAYER -> viewerPubkey to (state.blackPubkey ?: "")
+                ViewerRole.BLACK_PLAYER -> viewerPubkey to (state.whitePubkey ?: "")
+                ViewerRole.SPECTATOR -> viewerPubkey to (state.blackPubkey ?: "")
+            }
+
+        return LiveChessGameState(
+            startEventId = state.startEventId,
+            playerPubkey = playerPubkey,
+            opponentPubkey = opponentPubkey,
+            playerColor = state.playerColor,
+            engine = engine,
+            createdAt = state.challengeCreatedAt,
+            isSpectator = state.viewerRole == ViewerRole.SPECTATOR,
+            isPendingChallenge = state.isPendingChallenge,
+            initialHeadEventId = state.headEventId,
+        ).also { gameState ->
+            // Mark all loaded moves as received to prevent re-application during polling
+            gameState.markMovesAsReceived(state.appliedMoveNumbers)
+
+            // Mark finished if the game has ended
+            if (state.isFinished() && state.gameStatus is com.vitorpamplona.quartz.nip64Chess.GameStatus.Finished) {
+                gameState.markAsFinished(
+                    (state.gameStatus as com.vitorpamplona.quartz.nip64Chess.GameStatus.Finished).result,
+                )
+            }
+
+            // Handle pending draw offer
+            val drawOfferer = state.pendingDrawOffer
+            if (drawOfferer != null && drawOfferer != viewerPubkey) {
+                gameState.receiveDrawOffer(drawOfferer)
+            }
+        }
+    }
+
+    /**
+     * Load a game using the deterministic reconstruction algorithm.
+     *
+     * @param events Collected Jester events for the game
+     * @param viewerPubkey The pubkey of the user viewing the game
+     * @return Pair of (LiveChessGameState, ReconstructedGameState) or null if failed
+     */
+    fun loadGame(
+        events: JesterGameEvents,
+        viewerPubkey: String,
+    ): LoadGameResult {
+        val result = ChessStateReconstructor.reconstruct(events, viewerPubkey)
+
+        return when (result) {
+            is ReconstructionResult.Success -> {
+                val liveState = toLiveGameState(result, viewerPubkey)
+                if (liveState != null) {
+                    LoadGameResult.Success(liveState, result.state)
+                } else {
+                    LoadGameResult.Error("Failed to convert reconstructed state to live state")
+                }
+            }
+
+            is ReconstructionResult.Error -> {
+                LoadGameResult.Error(result.message)
+            }
+        }
+    }
+
+    /**
+     * Create a new game state without any events (for when accepting a challenge locally).
+     *
+     * @param startEventId The start event ID (game identifier)
+     * @param playerPubkey The player's pubkey
+     * @param opponentPubkey The opponent's pubkey
+     * @param playerColor The player's color
+     * @return A fresh LiveChessGameState
+     */
+    fun createNewGame(
+        startEventId: String,
+        playerPubkey: String,
+        opponentPubkey: String,
+        playerColor: Color,
+        isPendingChallenge: Boolean = false,
+    ): LiveChessGameState {
+        val engine = ChessEngine()
+        engine.reset()
+
+        return LiveChessGameState(
+            startEventId = startEventId,
+            playerPubkey = playerPubkey,
+            opponentPubkey = opponentPubkey,
+            playerColor = playerColor,
+            engine = engine,
+            isPendingChallenge = isPendingChallenge,
+        )
+    }
+}
+
+/**
+ * Result of loading a game.
+ */
+sealed class LoadGameResult {
+    data class Success(
+        val liveState: LiveChessGameState,
+        val reconstructedState: ReconstructedGameState,
+    ) : LoadGameResult()
+
+    data class Error(
+        val message: String,
+    ) : LoadGameResult()
+
+    fun isSuccess(): Boolean = this is Success
+
+    fun getOrNull(): LiveChessGameState? = (this as? Success)?.liveState
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/ChessGameViewer.kt

@@ -0,0 +1,172 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.aspectRatio
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.material3.Card
+import androidx.compose.material3.CardDefaults
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.text.font.FontFamily
+import androidx.compose.ui.unit.dp
+import com.vitorpamplona.quartz.nip64Chess.PGNParser
+
+/**
+ * Complete chess game viewer with board, metadata, and navigation
+ * Shared composable for Android and Desktop platforms
+ *
+ * Parses PGN content and displays:
+ * - Game metadata (event, players, result)
+ * - Interactive chess board
+ * - Move navigation controls
+ *
+ * @param pgnContent PGN format string
+ * @param modifier Modifier for the viewer
+ */
+@Composable
+fun ChessGameViewer(
+    pgnContent: String,
+    modifier: Modifier = Modifier,
+) {
+    val gameResult =
+        remember(pgnContent) {
+            PGNParser.parse(pgnContent)
+        }
+
+    gameResult.fold(
+        onSuccess = { game ->
+            ChessGameDisplay(game, modifier)
+        },
+        onFailure = { error ->
+            ChessGameError(
+                errorMessage = error.message ?: "Failed to parse PGN",
+                pgnContent = pgnContent,
+                modifier = modifier,
+            )
+        },
+    )
+}
+
+/**
+ * Displays a successfully parsed chess game
+ */
+@Composable
+private fun ChessGameDisplay(
+    game: com.vitorpamplona.quartz.nip64Chess.ChessGame,
+    modifier: Modifier = Modifier,
+) {
+    var currentMoveIndex by remember { mutableStateOf(0) }
+
+    Card(
+        modifier = modifier.fillMaxWidth(),
+        elevation = CardDefaults.cardElevation(defaultElevation = 2.dp),
+    ) {
+        Column(
+            modifier = Modifier.padding(16.dp),
+            horizontalAlignment = Alignment.CenterHorizontally,
+            verticalArrangement = Arrangement.spacedBy(12.dp),
+        ) {
+            // Game metadata header
+            PGNMetadata(game = game)
+
+            // Chess board
+            ChessBoard(
+                position = game.positionAt(currentMoveIndex),
+                modifier =
+                    Modifier
+                        .fillMaxWidth()
+                        .aspectRatio(1f),
+                boardSize = 320.dp,
+            )
+
+            // Move navigation
+            MoveNavigator(
+                currentMove = currentMoveIndex,
+                totalMoves = game.moves.size,
+                onMoveChange = { currentMoveIndex = it },
+            )
+        }
+    }
+}
+
+/**
+ * Displays error state when PGN parsing fails
+ */
+@Composable
+private fun ChessGameError(
+    errorMessage: String,
+    pgnContent: String,
+    modifier: Modifier = Modifier,
+) {
+    Card(
+        modifier = modifier.fillMaxWidth(),
+        colors =
+            CardDefaults.cardColors(
+                containerColor = MaterialTheme.colorScheme.errorContainer,
+            ),
+    ) {
+        Column(
+            modifier = Modifier.padding(16.dp),
+            verticalArrangement = Arrangement.spacedBy(8.dp),
+        ) {
+            // Error title
+            Text(
+                text = "Invalid Chess Game",
+                style = MaterialTheme.typography.titleMedium,
+                color = MaterialTheme.colorScheme.error,
+            )
+
+            // Error message
+            Text(
+                text = errorMessage,
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onErrorContainer,
+            )
+
+            // PGN content label
+            Text(
+                text = "PGN Content:",
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onErrorContainer,
+                modifier = Modifier.padding(top = 4.dp),
+            )
+
+            // Raw PGN content
+            Text(
+                text = pgnContent,
+                style = MaterialTheme.typography.bodySmall,
+                fontFamily = FontFamily.Monospace,
+                color = MaterialTheme.colorScheme.onErrorContainer,
+            )
+        }
+    }
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/ChessLobbyCards.kt

@@ -0,0 +1,342 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import androidx.compose.foundation.BorderStroke
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.material3.Button
+import androidx.compose.material3.Card
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedButton
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.unit.dp
+import com.vitorpamplona.quartz.nip64Chess.ChessGameNameGenerator
+
+// Color constants for card borders
+private val IncomingChallengeColor = Color(0xFFFF9800) // Orange
+private val OpenChallengeColor = Color(0xFF4CAF50) // Green
+private val SpectatingColor = Color(0xFF9C27B0) // Purple
+private val LiveGameColor = Color(0xFF2196F3) // Blue
+
+/**
+ * Card for an active game where the user is a participant
+ */
+@Composable
+fun ActiveGameCard(
+    gameId: String,
+    opponentName: String,
+    isYourTurn: Boolean,
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+    avatar: @Composable (() -> Unit)? = null,
+) {
+    val gameName =
+        remember(gameId) {
+            ChessGameNameGenerator.extractDisplayName(gameId) ?: gameId.take(12)
+        }
+
+    Card(
+        modifier = modifier.fillMaxWidth().clickable(onClick = onClick),
+        border =
+            if (isYourTurn) {
+                BorderStroke(2.dp, MaterialTheme.colorScheme.primary)
+            } else {
+                null
+            },
+    ) {
+        Row(
+            modifier = Modifier.padding(16.dp).fillMaxWidth(),
+            horizontalArrangement = Arrangement.spacedBy(12.dp),
+            verticalAlignment = Alignment.CenterVertically,
+        ) {
+            avatar?.invoke()
+
+            Column(modifier = Modifier.weight(1f)) {
+                Text(
+                    gameName,
+                    style = MaterialTheme.typography.titleSmall,
+                    fontWeight = FontWeight.Bold,
+                    color = MaterialTheme.colorScheme.primary,
+                )
+                Text(
+                    "vs $opponentName",
+                    style = MaterialTheme.typography.bodyMedium,
+                )
+            }
+
+            Text(
+                if (isYourTurn) "Your turn" else "Waiting...",
+                style = MaterialTheme.typography.bodyMedium,
+                color = if (isYourTurn) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant,
+                fontWeight = if (isYourTurn) FontWeight.Bold else FontWeight.Normal,
+            )
+        }
+    }
+}
+
+/**
+ * Card for an incoming or open challenge
+ */
+@Composable
+fun ChallengeCard(
+    challengerName: String,
+    challengerPlaysWhite: Boolean,
+    isIncoming: Boolean,
+    onAccept: () -> Unit,
+    modifier: Modifier = Modifier,
+    avatar: @Composable (() -> Unit)? = null,
+) {
+    val borderColor = if (isIncoming) IncomingChallengeColor else OpenChallengeColor
+
+    Card(
+        modifier = modifier.fillMaxWidth(),
+        border = BorderStroke(2.dp, borderColor),
+    ) {
+        Row(
+            modifier = Modifier.padding(16.dp).fillMaxWidth(),
+            horizontalArrangement = Arrangement.spacedBy(12.dp),
+            verticalAlignment = Alignment.CenterVertically,
+        ) {
+            avatar?.invoke()
+
+            Column(modifier = Modifier.weight(1f)) {
+                Text(
+                    if (isIncoming) "Challenge from $challengerName" else "Open challenge by $challengerName",
+                    style = MaterialTheme.typography.bodyLarge,
+                    fontWeight = FontWeight.Medium,
+                )
+                Text(
+                    "Challenger plays ${if (challengerPlaysWhite) "White" else "Black"}",
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                )
+            }
+
+            Button(onClick = onAccept) {
+                Text("Accept")
+            }
+        }
+    }
+}
+
+/**
+ * Card for user's outgoing challenge (waiting for acceptance)
+ * Clickable so user can open the game board and make the first move when ready
+ */
+@Composable
+fun OutgoingChallengeCard(
+    opponentName: String?,
+    userPlaysWhite: Boolean,
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+    avatar: @Composable (() -> Unit)? = null,
+) {
+    Card(
+        modifier = modifier.fillMaxWidth().clickable(onClick = onClick),
+        border = BorderStroke(2.dp, MaterialTheme.colorScheme.primary),
+    ) {
+        Row(
+            modifier = Modifier.padding(16.dp).fillMaxWidth(),
+            horizontalArrangement = Arrangement.spacedBy(12.dp),
+            verticalAlignment = Alignment.CenterVertically,
+        ) {
+            avatar?.invoke()
+
+            Column(modifier = Modifier.weight(1f)) {
+                Text(
+                    if (opponentName != null) {
+                        "Challenge to $opponentName"
+                    } else {
+                        "Open challenge (awaiting opponent)"
+                    },
+                    style = MaterialTheme.typography.bodyLarge,
+                    fontWeight = FontWeight.Medium,
+                )
+                Text(
+                    "You play ${if (userPlaysWhite) "White" else "Black"}",
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                )
+            }
+
+            Text(
+                "Waiting...",
+                style = MaterialTheme.typography.bodyMedium,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+        }
+    }
+}
+
+/**
+ * Card for a game the user is spectating
+ */
+@Composable
+fun SpectatingGameCard(
+    moveCount: Int,
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    Card(
+        modifier = modifier.fillMaxWidth().clickable(onClick = onClick),
+        border = BorderStroke(1.dp, SpectatingColor),
+    ) {
+        Row(
+            modifier = Modifier.padding(16.dp).fillMaxWidth(),
+            horizontalArrangement = Arrangement.SpaceBetween,
+            verticalAlignment = Alignment.CenterVertically,
+        ) {
+            Column(modifier = Modifier.weight(1f)) {
+                Text(
+                    "Watching game",
+                    style = MaterialTheme.typography.bodyLarge,
+                    fontWeight = FontWeight.Medium,
+                )
+                Text(
+                    "$moveCount moves played",
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                )
+            }
+
+            Text(
+                "Spectating",
+                style = MaterialTheme.typography.bodyMedium,
+                color = SpectatingColor,
+                fontWeight = FontWeight.Medium,
+            )
+        }
+    }
+}
+
+/**
+ * Card for a public live game that can be watched
+ */
+@Composable
+fun PublicGameCard(
+    whiteName: String,
+    blackName: String,
+    moveCount: Int,
+    onWatch: () -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    Card(
+        modifier = modifier.fillMaxWidth(),
+        border = BorderStroke(1.dp, LiveGameColor),
+    ) {
+        Row(
+            modifier = Modifier.padding(16.dp).fillMaxWidth(),
+            horizontalArrangement = Arrangement.SpaceBetween,
+            verticalAlignment = Alignment.CenterVertically,
+        ) {
+            Column(modifier = Modifier.weight(1f)) {
+                Text(
+                    "$whiteName vs $blackName",
+                    style = MaterialTheme.typography.bodyLarge,
+                    fontWeight = FontWeight.Medium,
+                )
+                Text(
+                    "$moveCount moves",
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                )
+            }
+
+            OutlinedButton(onClick = onWatch) {
+                Text("Watch")
+            }
+        }
+    }
+}
+
+/**
+ * Card for a completed game in history
+ */
+@Composable
+fun CompletedGameCard(
+    opponentName: String,
+    result: String,
+    didUserWin: Boolean,
+    isDraw: Boolean,
+    moveCount: Int,
+    modifier: Modifier = Modifier,
+    avatar: @Composable (() -> Unit)? = null,
+) {
+    val resultText =
+        when {
+            isDraw -> "Draw"
+            didUserWin -> "Won"
+            else -> "Lost"
+        }
+
+    val resultColor =
+        when {
+            isDraw -> MaterialTheme.colorScheme.onSurfaceVariant
+
+            didUserWin -> Color(0xFF4CAF50)
+
+            // Green
+            else -> Color(0xFFF44336) // Red
+        }
+
+    Card(
+        modifier = modifier.fillMaxWidth(),
+    ) {
+        Row(
+            modifier = Modifier.padding(16.dp).fillMaxWidth(),
+            horizontalArrangement = Arrangement.spacedBy(12.dp),
+            verticalAlignment = Alignment.CenterVertically,
+        ) {
+            avatar?.invoke()
+
+            Column(modifier = Modifier.weight(1f)) {
+                Text(
+                    "vs $opponentName",
+                    style = MaterialTheme.typography.bodyLarge,
+                    fontWeight = FontWeight.Medium,
+                )
+                Text(
+                    "$moveCount moves • $result",
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                )
+            }
+
+            Text(
+                resultText,
+                style = MaterialTheme.typography.bodyMedium,
+                color = resultColor,
+                fontWeight = FontWeight.Bold,
+            )
+        }
+    }
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/ChessLobbyLogic.kt

@@ -0,0 +1,845 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import com.vitorpamplona.quartz.nip64Chess.ChessGameEnd
+import com.vitorpamplona.quartz.nip64Chess.ChessMoveEvent
+import com.vitorpamplona.quartz.nip64Chess.Color
+import com.vitorpamplona.quartz.nip64Chess.JesterEvent
+import com.vitorpamplona.quartz.nip64Chess.JesterGameEvents
+import com.vitorpamplona.quartz.nip64Chess.PieceType
+import com.vitorpamplona.quartz.utils.TimeUtils
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.launch
+
+/**
+ * Interface for platform-specific chess event publishing using Jester protocol.
+ *
+ * All chess events use kind 30 with JSON content:
+ * - Start events: content.kind=0
+ * - Move events: content.kind=1 with full history
+ */
+interface ChessEventPublisher {
+    /**
+     * Publish a game start event (challenge).
+     * Returns the startEventId (event ID) if successful.
+     */
+    suspend fun publishStart(
+        playerColor: Color,
+        opponentPubkey: String?,
+    ): String?
+
+    /**
+     * Publish a move event.
+     * Move events include full history and link to previous move.
+     */
+    suspend fun publishMove(move: ChessMoveEvent): String?
+
+    /**
+     * Publish a game end event (includes result in content).
+     */
+    suspend fun publishGameEnd(gameEnd: ChessGameEnd): Boolean
+
+    /**
+     * Get count of write relays for UI feedback.
+     */
+    fun getWriteRelayCount(): Int
+}
+
+/**
+ * Relay-first fetcher interface for Jester protocol.
+ * Platforms provide one-shot relay queries.
+ *
+ * Every fetch does: one-shot REQ → collect events → EOSE → close.
+ * No caching — relays are the single source of truth.
+ */
+interface ChessRelayFetcher {
+    /** Fetch all events for a specific game by startEventId */
+    suspend fun fetchGameEvents(startEventId: String): JesterGameEvents
+
+    /** Fetch recent start/challenge events with optional progress callback */
+    suspend fun fetchChallenges(onProgress: ((RelayFetchProgress) -> Unit)? = null): List<JesterEvent>
+
+    /** Fetch recent public game summaries for spectating */
+    suspend fun fetchRecentGames(): List<RelayGameSummary>
+
+    /** Fetch game IDs (startEventIds) where user is a participant */
+    suspend fun fetchUserGameIds(onProgress: ((RelayFetchProgress) -> Unit)? = null): Set<String>
+
+    /** Get the list of relay URLs that will be used for fetching */
+    fun getRelayUrls(): List<String>
+}
+
+/**
+ * Summary of a game found on relays (for lobby display / spectating)
+ */
+data class RelayGameSummary(
+    val startEventId: String,
+    val whitePubkey: String,
+    val blackPubkey: String,
+    val moveCount: Int,
+    val lastMoveTime: Long,
+    val isActive: Boolean,
+) {
+    // Legacy compatibility
+    @Deprecated("Use startEventId instead", ReplaceWith("startEventId"))
+    val gameId: String get() = startEventId
+}
+
+/**
+ * Shared chess lobby logic — relay-first architecture with Jester protocol.
+ *
+ * Both Android and Desktop use this identically.
+ * Platform-specific code only implements:
+ * - ChessEventPublisher: sign + broadcast events
+ * - ChessRelayFetcher: one-shot relay queries
+ * - IUserMetadataProvider: display names / avatars
+ */
+class ChessLobbyLogic(
+    private val userPubkey: String,
+    private val publisher: ChessEventPublisher,
+    private val fetcher: ChessRelayFetcher,
+    private val metadataProvider: IUserMetadataProvider,
+    private val scope: CoroutineScope,
+    pollingConfig: ChessPollingConfig = ChessPollingDefaults.android,
+) {
+    val state = ChessLobbyState(userPubkey, scope)
+
+    private val pollingDelegate =
+        ChessPollingDelegate(
+            config = pollingConfig,
+            scope = scope,
+            onRefreshGames = { gameIds -> refreshGames(gameIds) },
+            onRefreshChallenges = { refreshChallenges() },
+            onCleanup = { cleanupExpiredChallenges() },
+        )
+
+    // ========================================
+    // Lifecycle
+    // ========================================
+
+    fun startPolling() {
+        pollingDelegate.start()
+    }
+
+    fun stopPolling() {
+        pollingDelegate.stop()
+    }
+
+    /**
+     * Ensure a game ID is being polled for updates.
+     * Call this when entering a game screen to guarantee polling is active for that game.
+     */
+    fun ensureGamePolling(gameId: String) {
+        pollingDelegate.addGameId(gameId)
+    }
+
+    /**
+     * Set focused game mode - only poll this specific game.
+     * Call this when entering a game screen to avoid refreshing unrelated games.
+     * Also ensures the game is in the polling set.
+     */
+    fun setFocusedGame(gameId: String) {
+        pollingDelegate.addGameId(gameId)
+        pollingDelegate.setFocusedGame(gameId)
+    }
+
+    /**
+     * Clear focused game mode - return to lobby mode (poll all games).
+     * Call this when returning to the lobby screen.
+     */
+    fun clearFocusedGame() {
+        pollingDelegate.setFocusedGame(null)
+    }
+
+    fun forceRefresh() {
+        pollingDelegate.refreshNow()
+    }
+
+    // ========================================
+    // Incoming event routing (real-time / optimistic)
+    // ========================================
+
+    /**
+     * Route an incoming Jester event to the appropriate handler.
+     * Called by platform subscription callbacks for real-time updates.
+     */
+    fun handleIncomingEvent(event: JesterEvent) {
+        when {
+            event.isStartEvent() -> handleStartEvent(event)
+            event.isMoveEvent() -> handleMoveEvent(event)
+        }
+    }
+
+    private fun handleStartEvent(event: JesterEvent) {
+        val startEventId = event.id
+        val challengerColor = event.playerColor() ?: Color.WHITE
+
+        val challenge =
+            ChessChallenge(
+                eventId = event.id,
+                gameId = startEventId, // In Jester, gameId = startEventId
+                challengerPubkey = event.pubKey,
+                challengerDisplayName = metadataProvider.getDisplayName(event.pubKey),
+                challengerAvatarUrl = metadataProvider.getPictureUrl(event.pubKey),
+                opponentPubkey = event.opponentPubkey(),
+                challengerColor = challengerColor,
+                createdAt = event.createdAt,
+            )
+        state.addChallenge(challenge)
+    }
+
+    private fun handleMoveEvent(event: JesterEvent) {
+        val startEventId = event.startEventId() ?: return
+        val san = event.move() ?: return
+        val fen = event.fen() ?: return
+        val history = event.history()
+        val moveNumber = history.size
+
+        // Check if this is our game (we're either the author or tagged as opponent)
+        val opponentFromTag = event.opponentPubkey()
+        val isOurGame = event.pubKey == userPubkey || opponentFromTag == userPubkey
+
+        var gameState = state.getGameState(startEventId)
+
+        // If this is our game but we haven't loaded it yet, load it now
+        // This happens when someone accepts our challenge (makes first move)
+        if (gameState == null && isOurGame) {
+            handleGameAccepted(startEventId)
+            return // handleGameAccepted will load the game and poll for events
+        }
+
+        if (gameState == null) return
+
+        // Check for game end
+        val result = event.result()
+        if (result != null) {
+            val gameResult =
+                when (result) {
+                    "1-0" -> com.vitorpamplona.quartz.nip64Chess.GameResult.WHITE_WINS
+                    "0-1" -> com.vitorpamplona.quartz.nip64Chess.GameResult.BLACK_WINS
+                    "1/2-1/2" -> com.vitorpamplona.quartz.nip64Chess.GameResult.DRAW
+                    else -> null
+                }
+            if (gameResult != null) {
+                gameState.markAsFinished(gameResult)
+                state.moveToCompleted(startEventId, result, event.termination())
+                pollingDelegate.removeGameId(startEventId)
+                return
+            }
+        }
+
+        // Only apply opponent moves optimistically
+        if (event.pubKey != userPubkey) {
+            gameState.applyOpponentMove(san, fen, moveNumber)
+            // Update head event ID for move linking
+            gameState.updateHeadEventId(event.id)
+        }
+    }
+
+    // ========================================
+    // Challenge operations
+    // ========================================
+
+    fun createChallenge(
+        opponentPubkey: String? = null,
+        playerColor: Color = Color.WHITE,
+        timeControl: String? = null, // Not supported in Jester, kept for API compatibility
+    ) {
+        scope.launch(Dispatchers.Default) {
+            state.setBroadcastStatus(
+                ChessBroadcastStatus.Broadcasting(
+                    san = "Challenge",
+                    successCount = 0,
+                    totalRelays = publisher.getWriteRelayCount(),
+                ),
+            )
+
+            val startEventId = retryWithBackoffResult { publisher.publishStart(playerColor, opponentPubkey) }
+
+            if (startEventId != null) {
+                // Add challenge to local state - shows in "Your Challenges" section
+                val challenge =
+                    ChessChallenge(
+                        eventId = startEventId,
+                        gameId = startEventId,
+                        challengerPubkey = userPubkey,
+                        challengerDisplayName = metadataProvider.getDisplayName(userPubkey),
+                        challengerAvatarUrl = metadataProvider.getPictureUrl(userPubkey),
+                        opponentPubkey = opponentPubkey,
+                        challengerColor = playerColor,
+                        createdAt = TimeUtils.now(),
+                    )
+                state.addChallenge(challenge)
+                pollingDelegate.addGameId(startEventId)
+
+                state.setBroadcastStatus(
+                    ChessBroadcastStatus.Success("Challenge", publisher.getWriteRelayCount()),
+                )
+                delay(2000)
+                state.setBroadcastStatus(ChessBroadcastStatus.Idle)
+                state.setError(null)
+            } else {
+                state.setBroadcastStatus(
+                    ChessBroadcastStatus.Failed("Challenge", "Failed to publish"),
+                )
+                state.setError("Failed to create challenge")
+            }
+        }
+    }
+
+    /**
+     * Accept a challenge by loading the game and making the first move (if we're black)
+     * or waiting for opponent's move (if we're white).
+     *
+     * In Jester protocol, acceptance is implicit - we just track the game locally.
+     */
+    fun acceptChallenge(challenge: ChessChallenge) {
+        // Mark as accepted SYNCHRONOUSLY before launching coroutine
+        // This prevents race where navigation happens before coroutine runs,
+        // which would cause loadGame() to incorrectly mark as spectator
+        state.markAsAccepted(challenge.gameId)
+
+        state.removeChallenge(challenge.gameId)
+
+        // Add to polling delegate FIRST - before adding to activeGames
+        // This prevents race where Compose sees the game but forceRefresh() doesn't include it
+        pollingDelegate.addGameId(challenge.gameId)
+
+        scope.launch(Dispatchers.Default) {
+            val playerColor = challenge.challengerColor.opposite()
+            val gameState =
+                ChessGameLoader.createNewGame(
+                    startEventId = challenge.gameId, // gameId = startEventId in Jester
+                    playerPubkey = userPubkey,
+                    opponentPubkey = challenge.challengerPubkey,
+                    playerColor = playerColor,
+                )
+            state.addActiveGame(challenge.gameId, gameState)
+            state.selectGame(challenge.gameId)
+            state.setError(null)
+
+            // Immediately fetch game from relays to load any existing moves
+            // This ensures moves are loaded without waiting for polling interval
+            refreshGame(challenge.gameId)
+        }
+    }
+
+    /**
+     * Open user's own outgoing challenge to view the board and make moves.
+     * Creates game state and navigates to game view.
+     */
+    fun openOwnChallenge(challenge: ChessChallenge) {
+        // Add to polling delegate FIRST - before adding to activeGames
+        pollingDelegate.addGameId(challenge.gameId)
+
+        // Create game state with user's chosen color
+        val gameState =
+            ChessGameLoader.createNewGame(
+                startEventId = challenge.gameId,
+                playerPubkey = userPubkey,
+                opponentPubkey = challenge.opponentPubkey ?: "",
+                playerColor = challenge.challengerColor,
+                isPendingChallenge = true,
+            )
+
+        state.addActiveGame(challenge.gameId, gameState)
+        state.selectGame(challenge.gameId)
+
+        // Fetch from relays in case opponent has already made moves
+        scope.launch(Dispatchers.Default) {
+            refreshGame(challenge.gameId)
+        }
+    }
+
+    /**
+     * When we detect our challenge was accepted (opponent made first move), load game from relays.
+     */
+    fun handleGameAccepted(startEventId: String) {
+        scope.launch(Dispatchers.Default) {
+            state.setBroadcastStatus(ChessBroadcastStatus.Syncing(0f))
+
+            val events = fetcher.fetchGameEvents(startEventId)
+            val result = ChessGameLoader.loadGame(events, userPubkey)
+
+            when (result) {
+                is LoadGameResult.Success -> {
+                    state.addActiveGame(startEventId, result.liveState)
+                    pollingDelegate.addGameId(startEventId)
+                    state.setBroadcastStatus(ChessBroadcastStatus.Idle)
+                    state.setError(null)
+                }
+
+                is LoadGameResult.Error -> {
+                    state.setError("Failed to load game: ${result.message}")
+                    state.setBroadcastStatus(ChessBroadcastStatus.Idle)
+                }
+            }
+        }
+    }
+
+    // ========================================
+    // Game operations
+    // ========================================
+
+    fun publishMove(
+        startEventId: String,
+        from: String,
+        to: String,
+    ) {
+        val gameState = state.getGameState(startEventId) ?: return
+
+        if (state.isSpectating(startEventId)) {
+            state.setError("Cannot move while spectating")
+            return
+        }
+
+        // Parse promotion suffix from `to` if present (e.g., "e8q" -> "e8" + QUEEN)
+        val (actualTo, promotion) = parsePromotionFromTo(to)
+
+        val moveResult = gameState.makeMove(from, actualTo, promotion) ?: return
+
+        scope.launch(Dispatchers.Default) {
+            state.setBroadcastStatus(
+                ChessBroadcastStatus.Broadcasting(
+                    san = moveResult.san,
+                    successCount = 0,
+                    totalRelays = publisher.getWriteRelayCount(),
+                ),
+            )
+
+            val newEventId = retryWithBackoffResult { publisher.publishMove(moveResult) }
+
+            if (newEventId != null) {
+                // Update head event ID for next move linking
+                gameState.updateHeadEventId(newEventId)
+
+                state.setBroadcastStatus(
+                    ChessBroadcastStatus.Success(moveResult.san, publisher.getWriteRelayCount()),
+                )
+                delay(3000)
+
+                val currentState = state.getGameState(startEventId)
+                state.setBroadcastStatus(
+                    if (currentState?.isPlayerTurn() == false) {
+                        ChessBroadcastStatus.WaitingForOpponent
+                    } else {
+                        ChessBroadcastStatus.Idle
+                    },
+                )
+                state.setError(null)
+            } else {
+                // Revert the move since publishing failed
+                gameState.undoLastMove()
+
+                state.setBroadcastStatus(
+                    ChessBroadcastStatus.Failed(moveResult.san, "Failed to publish move"),
+                )
+                state.setError("Failed to publish move - move reverted")
+            }
+        }
+    }
+
+    fun resign(startEventId: String) {
+        val gameState = state.getGameState(startEventId) ?: return
+
+        if (state.isSpectating(startEventId)) {
+            state.setError("Cannot resign while spectating")
+            return
+        }
+
+        scope.launch(Dispatchers.Default) {
+            val endData = gameState.resign()
+            val success = retryWithBackoff { publisher.publishGameEnd(endData) }
+
+            if (success) {
+                state.moveToCompleted(startEventId, endData.result.notation, endData.termination.name.lowercase())
+                pollingDelegate.removeGameId(startEventId)
+                state.setError(null)
+            } else {
+                state.setError("Failed to resign")
+            }
+        }
+    }
+
+    fun claimAbandonmentVictory(startEventId: String) {
+        val gameState = state.getGameState(startEventId) ?: return
+        val endData = gameState.claimAbandonmentVictory() ?: return
+
+        scope.launch(Dispatchers.Default) {
+            val success = retryWithBackoff { publisher.publishGameEnd(endData) }
+
+            if (success) {
+                state.moveToCompleted(startEventId, endData.result.notation, "abandonment")
+                pollingDelegate.removeGameId(startEventId)
+                state.setError(null)
+            } else {
+                state.setError("Failed to claim abandonment victory")
+            }
+        }
+    }
+
+    // ========================================
+    // Spectator mode
+    // ========================================
+
+    fun loadGameAsSpectator(startEventId: String) {
+        scope.launch(Dispatchers.Default) {
+            state.setBroadcastStatus(ChessBroadcastStatus.Syncing(0f))
+
+            val events = fetcher.fetchGameEvents(startEventId)
+            val result = ChessGameLoader.loadGame(events, userPubkey)
+
+            when (result) {
+                is LoadGameResult.Success -> {
+                    state.addSpectatingGame(startEventId, result.liveState)
+                    pollingDelegate.addGameId(startEventId)
+                    state.setBroadcastStatus(ChessBroadcastStatus.Idle)
+                    state.setError(null)
+                    // Auto-select the game for Desktop (Android uses route navigation)
+                    state.selectGame(startEventId)
+                }
+
+                is LoadGameResult.Error -> {
+                    state.setError("Failed to load game: ${result.message}")
+                    state.setBroadcastStatus(ChessBroadcastStatus.Idle)
+                }
+            }
+        }
+    }
+
+    fun loadGame(startEventId: String) {
+        scope.launch(Dispatchers.Default) {
+            // Don't load if game already exists or was accepted (acceptChallenge will handle it)
+            if (state.getGameState(startEventId) != null || state.wasAccepted(startEventId)) {
+                return@launch
+            }
+
+            state.setBroadcastStatus(ChessBroadcastStatus.Syncing(0f))
+
+            val events = fetcher.fetchGameEvents(startEventId)
+            val result = ChessGameLoader.loadGame(events, userPubkey)
+
+            when (result) {
+                is LoadGameResult.Success -> {
+                    if (result.liveState.isSpectator) {
+                        state.addSpectatingGame(startEventId, result.liveState)
+                    } else {
+                        state.addActiveGame(startEventId, result.liveState)
+                    }
+                    pollingDelegate.addGameId(startEventId)
+                    state.setBroadcastStatus(ChessBroadcastStatus.Idle)
+                    state.setError(null)
+                }
+
+                is LoadGameResult.Error -> {
+                    // Check again if game was added while we were fetching
+                    // (e.g., by acceptChallenge completing in parallel)
+                    if (state.getGameState(startEventId) != null) {
+                        state.setBroadcastStatus(ChessBroadcastStatus.Idle)
+                        return@launch
+                    }
+                    state.setError("Failed to load game: ${result.message}")
+                    state.setBroadcastStatus(ChessBroadcastStatus.Idle)
+                }
+            }
+        }
+    }
+
+    // ========================================
+    // Relay-first refresh (periodic reconstruction)
+    // ========================================
+
+    private suspend fun refreshGames(gameIds: Set<String>) {
+        for (gameId in gameIds) {
+            refreshGame(gameId)
+        }
+    }
+
+    private suspend fun refreshGame(startEventId: String) {
+        val events = fetcher.fetchGameEvents(startEventId)
+
+        val result = ChessGameLoader.loadGame(events, userPubkey)
+
+        when (result) {
+            is LoadGameResult.Success -> {
+                state.replaceGameState(startEventId, result.liveState)
+            }
+
+            is LoadGameResult.Error -> {
+                // Don't overwrite error for periodic refresh failures
+            }
+        }
+    }
+
+    private suspend fun refreshChallenges() {
+        state.setRefreshing(true)
+        try {
+            refreshChallengesInternal()
+        } finally {
+            state.setRefreshing(false)
+        }
+    }
+
+    private suspend fun refreshChallengesInternal() {
+        val relayUrls = fetcher.getRelayUrls()
+        val relayStatesMap = mutableMapOf<String, RelaySyncState>()
+        relayUrls.forEach { url ->
+            val displayName = url.substringAfter("://").substringBefore("/")
+            relayStatesMap[url] = RelaySyncState(url, displayName, RelaySyncStatus.CONNECTING, 0)
+        }
+        var totalEvents = 0
+
+        state.setSyncStatus(
+            ChessSyncStatus.Syncing(
+                phase = "challenges",
+                relayStates = relayStatesMap.values.toList(),
+                totalEventsReceived = 0,
+            ),
+        )
+
+        val startEvents =
+            fetcher.fetchChallenges { progress ->
+                val relayUrl = progress.relay.url
+                val displayName = relayUrl.substringAfter("://").substringBefore("/")
+                val status =
+                    when (progress.status) {
+                        RelayFetchStatus.WAITING -> RelaySyncStatus.WAITING
+                        RelayFetchStatus.RECEIVING -> RelaySyncStatus.RECEIVING
+                        RelayFetchStatus.EOSE_RECEIVED -> RelaySyncStatus.EOSE_RECEIVED
+                        RelayFetchStatus.TIMEOUT -> RelaySyncStatus.FAILED
+                    }
+                relayStatesMap[relayUrl] =
+                    RelaySyncState(
+                        relayUrl,
+                        displayName,
+                        status,
+                        progress.eventCount,
+                    )
+                totalEvents = relayStatesMap.values.sumOf { it.eventsReceived }
+                state.setSyncStatus(
+                    ChessSyncStatus.Syncing(
+                        phase = "challenges",
+                        relayStates = relayStatesMap.values.toList(),
+                        totalEventsReceived = totalEvents,
+                    ),
+                )
+            }
+
+        val fetchedChallenges =
+            startEvents.mapNotNull { event ->
+                if (!event.isStartEvent()) return@mapNotNull null
+                val startEventId = event.id
+
+                // Skip challenges that user has already accepted
+                if (state.wasAccepted(startEventId)) return@mapNotNull null
+
+                val challengerColor = event.playerColor() ?: Color.WHITE
+
+                ChessChallenge(
+                    eventId = event.id,
+                    gameId = startEventId,
+                    challengerPubkey = event.pubKey,
+                    challengerDisplayName = metadataProvider.getDisplayName(event.pubKey),
+                    challengerAvatarUrl = metadataProvider.getPictureUrl(event.pubKey),
+                    opponentPubkey = event.opponentPubkey(),
+                    challengerColor = challengerColor,
+                    createdAt = event.createdAt,
+                )
+            }
+
+        // Merge only RECENT optimistic challenges (created in last 5 minutes, not yet propagated)
+        // This prevents stale challenges from accumulating across sessions
+        // Also exclude challenges that user has accepted (tracked in _acceptedGameIds)
+        val now = TimeUtils.now()
+        val recentThreshold = 5 * 60L // 5 minutes
+        val fetchedGameIds = fetchedChallenges.map { it.gameId }.toSet()
+        val optimisticChallenges =
+            state.challenges.value.filter { challenge ->
+                val isRecent = (now - challenge.createdAt) < recentThreshold
+                val notFetched = challenge.gameId !in fetchedGameIds
+                val notAccepted = !state.wasAccepted(challenge.gameId)
+                isRecent && notFetched && notAccepted
+            }
+        val mergedChallenges = fetchedChallenges + optimisticChallenges
+
+        state.updateChallenges(mergedChallenges)
+
+        state.setSyncStatus(
+            ChessSyncStatus.Syncing(
+                phase = "games",
+                relayStates = relayStatesMap.values.toList(),
+                totalEventsReceived = totalEvents,
+            ),
+        )
+
+        discoverUserGames()
+
+        val recentGames = fetcher.fetchRecentGames()
+        val publicGames =
+            recentGames.map { summary ->
+                PublicGame(
+                    gameId = summary.startEventId,
+                    whitePubkey = summary.whitePubkey,
+                    whiteDisplayName = metadataProvider.getDisplayName(summary.whitePubkey),
+                    blackPubkey = summary.blackPubkey,
+                    blackDisplayName = metadataProvider.getDisplayName(summary.blackPubkey),
+                    moveCount = summary.moveCount,
+                    lastMoveTime = summary.lastMoveTime,
+                    isActive = summary.isActive,
+                )
+            }
+        state.updatePublicGames(publicGames)
+
+        val failedCount = relayStatesMap.values.count { it.status == RelaySyncStatus.FAILED }
+        val activeGamesCount = state.activeGames.value.size
+
+        if (failedCount > 0 && failedCount < relayStatesMap.size) {
+            state.setSyncStatus(
+                ChessSyncStatus.PartialSync(
+                    relayStates = relayStatesMap.values.toList(),
+                    message = "$failedCount relay(s) timed out",
+                ),
+            )
+        } else if (failedCount == relayStatesMap.size) {
+            state.setSyncStatus(
+                ChessSyncStatus.PartialSync(
+                    relayStates = relayStatesMap.values.toList(),
+                    message = "All relays failed",
+                ),
+            )
+        } else {
+            state.setSyncStatus(
+                ChessSyncStatus.Synced(
+                    relayStates = relayStatesMap.values.toList(),
+                    challengeCount = mergedChallenges.size,
+                    gameCount = activeGamesCount,
+                    totalEventsReceived = totalEvents,
+                ),
+            )
+        }
+    }
+
+    private suspend fun discoverUserGames() {
+        val discoveredGameIds = fetcher.fetchUserGameIds()
+        val currentActiveIds = state.activeGames.value.keys
+        val currentSpectatingIds = state.spectatingGames.value.keys
+
+        val newGameIds = discoveredGameIds - currentActiveIds - currentSpectatingIds
+
+        for (startEventId in newGameIds) {
+            val events = fetcher.fetchGameEvents(startEventId)
+            val result = ChessGameLoader.loadGame(events, userPubkey)
+
+            when (result) {
+                is LoadGameResult.Success -> {
+                    if (!result.liveState.isSpectator) {
+                        state.addActiveGame(startEventId, result.liveState)
+                        pollingDelegate.addGameId(startEventId)
+                    }
+                }
+
+                is LoadGameResult.Error -> {
+                    // Failed to load game - continue with others
+                }
+            }
+        }
+    }
+
+    private fun cleanupExpiredChallenges() {
+        val now = TimeUtils.now()
+        val validChallenges =
+            state.challenges.value.filter { challenge ->
+                (now - challenge.createdAt) < CHALLENGE_EXPIRY_SECONDS
+            }
+        state.updateChallenges(validChallenges)
+    }
+
+    // ========================================
+    // Utilities
+    // ========================================
+
+    private suspend fun retryWithBackoff(
+        maxRetries: Int = 3,
+        initialDelayMs: Long = 1000,
+        action: suspend () -> Boolean,
+    ): Boolean {
+        var delayMs = initialDelayMs
+        repeat(maxRetries) { attempt ->
+            if (action()) return true
+            if (attempt < maxRetries - 1) {
+                delay(delayMs)
+                delayMs *= 2
+            }
+        }
+        return false
+    }
+
+    private suspend fun <T> retryWithBackoffResult(
+        maxRetries: Int = 3,
+        initialDelayMs: Long = 1000,
+        action: suspend () -> T?,
+    ): T? {
+        var delayMs = initialDelayMs
+        repeat(maxRetries) { attempt ->
+            val result = action()
+            if (result != null) return result
+            if (attempt < maxRetries - 1) {
+                delay(delayMs)
+                delayMs *= 2
+            }
+        }
+        return null
+    }
+
+    fun clearError() {
+        state.setError(null)
+    }
+
+    fun selectGame(gameId: String?) {
+        state.selectGame(gameId)
+    }
+}
+
+/**
+ * Parse promotion piece from a "to" square string.
+ * For example: "e8q" -> Pair("e8", PieceType.QUEEN)
+ * Regular moves: "e4" -> Pair("e4", null)
+ */
+private fun parsePromotionFromTo(to: String): Pair<String, PieceType?> {
+    if (to.length == 3) {
+        val square = to.take(2)
+        val promotion =
+            when (to.last().lowercaseChar()) {
+                'q' -> PieceType.QUEEN
+                'r' -> PieceType.ROOK
+                'b' -> PieceType.BISHOP
+                'n' -> PieceType.KNIGHT
+                else -> null
+            }
+        if (promotion != null) {
+            return square to promotion
+        }
+    }
+    return to to null
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/ChessLobbyState.kt

@@ -0,0 +1,518 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import androidx.compose.runtime.Immutable
+import com.vitorpamplona.quartz.nip64Chess.Color
+import com.vitorpamplona.quartz.nip64Chess.LiveChessGameState
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.update
+import java.util.concurrent.atomic.AtomicLong
+
+/**
+ * Challenge expiry: 24 hours
+ */
+const val CHALLENGE_EXPIRY_SECONDS = 24 * 60 * 60L
+
+/**
+ * Represents a chess challenge that can be displayed in the lobby
+ */
+@Immutable
+data class ChessChallenge(
+    val eventId: String,
+    val gameId: String,
+    val challengerPubkey: String,
+    val challengerDisplayName: String?,
+    val challengerAvatarUrl: String?,
+    val opponentPubkey: String?,
+    val challengerColor: Color,
+    val createdAt: Long,
+) {
+    /** Whether this is an open challenge anyone can accept */
+    val isOpen: Boolean get() = opponentPubkey == null
+
+    /** Whether this challenge is directed at a specific user */
+    fun isDirectedAt(pubkey: String): Boolean = opponentPubkey == pubkey
+
+    /** Whether this challenge was created by a specific user */
+    fun isFrom(pubkey: String): Boolean = challengerPubkey == pubkey
+}
+
+/**
+ * Represents a public game that can be spectated
+ */
+@Immutable
+data class PublicGame(
+    val gameId: String,
+    val whitePubkey: String,
+    val whiteDisplayName: String?,
+    val blackPubkey: String,
+    val blackDisplayName: String?,
+    val moveCount: Int,
+    val lastMoveTime: Long,
+    val isActive: Boolean,
+)
+
+/**
+ * Represents a completed game for history display
+ */
+@Immutable
+data class CompletedGame(
+    val gameId: String,
+    val whitePubkey: String,
+    val whiteDisplayName: String?,
+    val blackPubkey: String,
+    val blackDisplayName: String?,
+    val result: String,
+    val termination: String?,
+    val moveCount: Int,
+    val completedAt: Long,
+) {
+    /** Whether user won this game */
+    fun didUserWin(userPubkey: String): Boolean =
+        when (result) {
+            "1-0" -> whitePubkey == userPubkey
+            "0-1" -> blackPubkey == userPubkey
+            else -> false
+        }
+
+    /** Whether this was a draw */
+    val isDraw: Boolean get() = result == "1/2-1/2"
+}
+
+/**
+ * Individual relay status during sync
+ */
+@Immutable
+data class RelaySyncState(
+    val url: String,
+    val displayName: String,
+    val status: RelaySyncStatus,
+    val eventsReceived: Int = 0,
+)
+
+@Immutable
+enum class RelaySyncStatus {
+    CONNECTING,
+    WAITING,
+    RECEIVING,
+    EOSE_RECEIVED,
+    FAILED,
+}
+
+/**
+ * Sync status for incoming events (subscription-side)
+ */
+@Immutable
+sealed class ChessSyncStatus {
+    data object Idle : ChessSyncStatus()
+
+    data class Syncing(
+        val phase: String,
+        val relayStates: List<RelaySyncState>,
+        val totalEventsReceived: Int,
+    ) : ChessSyncStatus() {
+        val connectedCount: Int get() = relayStates.count { it.status != RelaySyncStatus.FAILED }
+        val eoseCount: Int get() = relayStates.count { it.status == RelaySyncStatus.EOSE_RECEIVED }
+        val totalCount: Int get() = relayStates.size
+    }
+
+    data class Synced(
+        val relayStates: List<RelaySyncState>,
+        val challengeCount: Int,
+        val gameCount: Int,
+        val totalEventsReceived: Int,
+    ) : ChessSyncStatus() {
+        val successCount: Int get() = relayStates.count { it.status == RelaySyncStatus.EOSE_RECEIVED }
+        val totalCount: Int get() = relayStates.size
+    }
+
+    data class PartialSync(
+        val relayStates: List<RelaySyncState>,
+        val message: String,
+    ) : ChessSyncStatus() {
+        val successCount: Int get() = relayStates.count { it.status == RelaySyncStatus.EOSE_RECEIVED }
+        val failedCount: Int get() = relayStates.count { it.status == RelaySyncStatus.FAILED }
+        val totalCount: Int get() = relayStates.size
+    }
+}
+
+/**
+ * Chess status for UI feedback
+ */
+@Immutable
+sealed class ChessBroadcastStatus {
+    data object Idle : ChessBroadcastStatus()
+
+    data class Broadcasting(
+        val san: String,
+        val successCount: Int,
+        val totalRelays: Int,
+    ) : ChessBroadcastStatus() {
+        val progress: Float get() = if (totalRelays > 0) successCount.toFloat() / totalRelays else 0f
+    }
+
+    data class Success(
+        val san: String,
+        val relayCount: Int,
+    ) : ChessBroadcastStatus()
+
+    data class Failed(
+        val san: String,
+        val error: String,
+    ) : ChessBroadcastStatus()
+
+    data object WaitingForOpponent : ChessBroadcastStatus()
+
+    data class Syncing(
+        val progress: Float = 0f,
+    ) : ChessBroadcastStatus()
+
+    data class Desynced(
+        val message: String,
+    ) : ChessBroadcastStatus()
+}
+
+/**
+ * Shared chess lobby state that can be used by both Android and Desktop
+ */
+class ChessLobbyState(
+    private val userPubkey: String,
+    private val scope: CoroutineScope,
+) {
+    // Active games where user is a participant
+    private val _activeGames = MutableStateFlow<Map<String, LiveChessGameState>>(emptyMap())
+    val activeGames: StateFlow<Map<String, LiveChessGameState>> = _activeGames.asStateFlow()
+
+    // Public games that can be spectated
+    private val _publicGames = MutableStateFlow<List<PublicGame>>(emptyList())
+    val publicGames: StateFlow<List<PublicGame>> = _publicGames.asStateFlow()
+
+    // All challenges (filtered by UI based on type)
+    private val _challenges = MutableStateFlow<List<ChessChallenge>>(emptyList())
+    val challenges: StateFlow<List<ChessChallenge>> = _challenges.asStateFlow()
+
+    // Spectating games (user is watching but not playing)
+    private val _spectatingGames = MutableStateFlow<Map<String, LiveChessGameState>>(emptyMap())
+    val spectatingGames: StateFlow<Map<String, LiveChessGameState>> = _spectatingGames.asStateFlow()
+
+    // Completed games history
+    private val _completedGames = MutableStateFlow<List<CompletedGame>>(emptyList())
+    val completedGames: StateFlow<List<CompletedGame>> = _completedGames.asStateFlow()
+
+    // Game IDs that user has accepted - uses global singleton to share across ViewModel instances
+    // This is critical because lobby and game screen may have different ViewModel instances
+
+    // Broadcast status
+    private val _broadcastStatus = MutableStateFlow<ChessBroadcastStatus>(ChessBroadcastStatus.Idle)
+    val broadcastStatus: StateFlow<ChessBroadcastStatus> = _broadcastStatus.asStateFlow()
+
+    // Error state
+    private val _error = MutableStateFlow<String?>(null)
+    val error: StateFlow<String?> = _error.asStateFlow()
+
+    // Loading/refreshing state
+    private val _isRefreshing = MutableStateFlow(false)
+    val isRefreshing: StateFlow<Boolean> = _isRefreshing.asStateFlow()
+
+    // Sync status for subscription banner
+    private val _syncStatus = MutableStateFlow<ChessSyncStatus>(ChessSyncStatus.Idle)
+    val syncStatus: StateFlow<ChessSyncStatus> = _syncStatus.asStateFlow()
+
+    // Selected game ID for navigation
+    private val _selectedGameId = MutableStateFlow<String?>(null)
+    val selectedGameId: StateFlow<String?> = _selectedGameId.asStateFlow()
+
+    // State version counter - increments on every game state update
+    // UI can observe this to force recomposition when internal state changes
+    private val stateVersionCounter = AtomicLong(0)
+    private val _stateVersion = MutableStateFlow(0L)
+    val stateVersion: StateFlow<Long> = _stateVersion.asStateFlow()
+
+    // Badge count (incoming challenges + your turn games)
+    val badgeCount: Int
+        get() {
+            val incomingChallenges = _challenges.value.count { it.isDirectedAt(userPubkey) }
+            val yourTurnGames = _activeGames.value.values.count { it.isPlayerTurn() }
+            return incomingChallenges + yourTurnGames
+        }
+
+    // ========================================
+    // Derived state for UI sections
+    // ========================================
+
+    /** Challenges directed at the user */
+    fun incomingChallenges(): List<ChessChallenge> = _challenges.value.filter { it.isDirectedAt(userPubkey) }
+
+    /** Challenges created by the user */
+    fun outgoingChallenges(): List<ChessChallenge> = _challenges.value.filter { it.isFrom(userPubkey) }
+
+    /** Open challenges from others that user can join */
+    fun openChallenges(): List<ChessChallenge> = _challenges.value.filter { it.isOpen && !it.isFrom(userPubkey) }
+
+    // ========================================
+    // State updates
+    // ========================================
+
+    fun updateChallenges(challenges: List<ChessChallenge>) {
+        _challenges.value = challenges
+    }
+
+    fun addChallenge(challenge: ChessChallenge) {
+        _challenges.update { current ->
+            if (current.any { it.eventId == challenge.eventId || it.gameId == challenge.gameId }) {
+                current
+            } else {
+                current + challenge
+            }
+        }
+    }
+
+    fun removeChallenge(gameId: String) {
+        _challenges.update { current ->
+            current.filter { it.gameId != gameId }
+        }
+    }
+
+    fun updatePublicGames(games: List<PublicGame>) {
+        _publicGames.value = games
+    }
+
+    fun addActiveGame(
+        gameId: String,
+        state: LiveChessGameState,
+    ) {
+        _activeGames.update { current ->
+            val existing = current[gameId]
+            if (existing != null) {
+                // Only replace if new state has at least as many moves
+                val existingMoves = existing.moveHistory.value.size
+                val newMoves = state.moveHistory.value.size
+                if (newMoves < existingMoves) {
+                    return@update current
+                }
+            }
+            current + (gameId to state)
+        }
+        // Track as accepted to prevent refresh from re-adding as optimistic challenge
+        AcceptedGamesRegistry.markAsAccepted(gameId)
+        // Remove from challenges if present
+        removeChallenge(gameId)
+    }
+
+    fun removeActiveGame(gameId: String) {
+        _activeGames.update { it - gameId }
+    }
+
+    fun updateActiveGame(
+        gameId: String,
+        update: (LiveChessGameState) -> LiveChessGameState,
+    ) {
+        _activeGames.update { current ->
+            current[gameId]?.let { state ->
+                current + (gameId to update(state))
+            } ?: current
+        }
+    }
+
+    /**
+     * Replace game state entirely after full reconstruction from relays.
+     * Preserves game location (active vs spectating).
+     *
+     * IMPORTANT: Only replaces if new state has >= moves than current state.
+     * This prevents race conditions where polling refresh could revert
+     * a user's move before it propagates to relays.
+     *
+     * IMPORTANT: Never replace a participant game with a spectator state.
+     * This prevents the race where relay fetch returns before acceptance propagates,
+     * which would incorrectly mark an accepted game as spectating.
+     */
+    fun replaceGameState(
+        gameId: String,
+        newState: LiveChessGameState,
+    ) {
+        val inActiveGames = _activeGames.value.containsKey(gameId)
+        val inSpectatingGames = _spectatingGames.value.containsKey(gameId)
+
+        val currentState = _activeGames.value[gameId] ?: _spectatingGames.value[gameId]
+        val currentMoveCount = currentState?.moveHistory?.value?.size ?: 0
+        val newMoveCount = newState.moveHistory.value.size
+
+        // Only replace if new state has at least as many moves
+        // This prevents reverting user's local moves during refresh
+        if (newMoveCount < currentMoveCount) {
+            return
+        }
+
+        // Handle case where new state incorrectly has isSpectator=true but current is participant
+        // This happens with open challenges where opponent can't be determined from relay events alone
+        // Solution: Apply moves from new state while preserving participant status from current
+        val stateToUse =
+            if (currentState != null && !currentState.isSpectator && newState.isSpectator && newMoveCount > currentMoveCount) {
+                // Apply opponent's moves to current state's engine
+                currentState.applyMovesFrom(newState)
+                currentState // Keep using current state with updated engine
+            } else if (currentState != null && !currentState.isSpectator && newState.isSpectator) {
+                return
+            } else {
+                newState
+            }
+
+        if (inActiveGames) {
+            _activeGames.update { it + (gameId to stateToUse) }
+            // Increment version to force UI recomposition even if map equals() returns true
+            val newVersion = stateVersionCounter.incrementAndGet()
+            _stateVersion.value = newVersion
+        } else if (inSpectatingGames) {
+            _spectatingGames.update { it + (gameId to stateToUse) }
+            val newVersion = stateVersionCounter.incrementAndGet()
+            _stateVersion.value = newVersion
+        }
+    }
+
+    /**
+     * Move a game from active/spectating to completed.
+     * Display names are optional; UI can look them up later if needed.
+     */
+    fun moveToCompleted(
+        gameId: String,
+        result: String,
+        termination: String?,
+        whiteDisplayName: String? = null,
+        blackDisplayName: String? = null,
+    ) {
+        val existingState = _activeGames.value[gameId] ?: _spectatingGames.value[gameId]
+        existingState?.let { gameState ->
+            // Derive white/black pubkeys from player color
+            val whitePubkey =
+                if (gameState.playerColor == Color.WHITE) {
+                    gameState.playerPubkey
+                } else {
+                    gameState.opponentPubkey
+                }
+            val blackPubkey =
+                if (gameState.playerColor == Color.BLACK) {
+                    gameState.playerPubkey
+                } else {
+                    gameState.opponentPubkey
+                }
+
+            val completed =
+                CompletedGame(
+                    gameId = gameId,
+                    whitePubkey = whitePubkey,
+                    whiteDisplayName = whiteDisplayName,
+                    blackPubkey = blackPubkey,
+                    blackDisplayName = blackDisplayName,
+                    result = result,
+                    termination = termination,
+                    moveCount = gameState.moveHistory.value.size,
+                    completedAt =
+                        com.vitorpamplona.quartz.utils.TimeUtils
+                            .now(),
+                )
+
+            _completedGames.update { current ->
+                // Avoid duplicates
+                if (current.any { it.gameId == gameId }) {
+                    current
+                } else {
+                    listOf(completed) + current
+                }
+            }
+
+            // Remove from active/spectating
+            _activeGames.update { it - gameId }
+            _spectatingGames.update { it - gameId }
+
+            // Clear selection if this game was selected
+            if (_selectedGameId.value == gameId) {
+                _selectedGameId.value = null
+            }
+        }
+    }
+
+    fun addSpectatingGame(
+        gameId: String,
+        state: LiveChessGameState,
+    ) {
+        // Never add to spectating if this game was accepted - user is a participant
+        if (AcceptedGamesRegistry.wasAccepted(gameId)) {
+            // Add to active games instead
+            _activeGames.update { it + (gameId to state) }
+            return
+        }
+        _spectatingGames.update { it + (gameId to state) }
+    }
+
+    fun removeSpectatingGame(gameId: String) {
+        _spectatingGames.update { it - gameId }
+    }
+
+    fun setBroadcastStatus(status: ChessBroadcastStatus) {
+        _broadcastStatus.value = status
+    }
+
+    fun setError(error: String?) {
+        _error.value = error
+    }
+
+    fun setRefreshing(refreshing: Boolean) {
+        _isRefreshing.value = refreshing
+    }
+
+    fun setSyncStatus(status: ChessSyncStatus) {
+        _syncStatus.value = status
+    }
+
+    fun selectGame(gameId: String?) {
+        _selectedGameId.value = gameId
+    }
+
+    fun getGameState(gameId: String): LiveChessGameState? = _activeGames.value[gameId] ?: _spectatingGames.value[gameId]
+
+    fun isUserParticipant(gameId: String): Boolean = _activeGames.value.containsKey(gameId)
+
+    fun isSpectating(gameId: String): Boolean = _spectatingGames.value.containsKey(gameId)
+
+    /** Whether a game ID was accepted (prevents refresh from re-adding as challenge) */
+    fun wasAccepted(gameId: String): Boolean = AcceptedGamesRegistry.wasAccepted(gameId)
+
+    /** Mark a game as accepted synchronously (call before async game creation) */
+    fun markAsAccepted(gameId: String) {
+        AcceptedGamesRegistry.markAsAccepted(gameId)
+    }
+
+    fun clearAll() {
+        _activeGames.value = emptyMap()
+        _publicGames.value = emptyList()
+        _challenges.value = emptyList()
+        _spectatingGames.value = emptyMap()
+        _completedGames.value = emptyList()
+        AcceptedGamesRegistry.clear()
+        _broadcastStatus.value = ChessBroadcastStatus.Idle
+        _error.value = null
+        _selectedGameId.value = null
+    }
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/ChessRelayFetchHelper.kt

@@ -0,0 +1,134 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import com.vitorpamplona.quartz.nip01Core.core.Event
+import com.vitorpamplona.quartz.nip01Core.relay.client.INostrClient
+import com.vitorpamplona.quartz.nip01Core.relay.client.reqs.IRequestListener
+import com.vitorpamplona.quartz.nip01Core.relay.client.single.newSubId
+import com.vitorpamplona.quartz.nip01Core.relay.filters.Filter
+import com.vitorpamplona.quartz.nip01Core.relay.normalizer.NormalizedRelayUrl
+import kotlinx.coroutines.CompletableDeferred
+import kotlinx.coroutines.withTimeoutOrNull
+import java.util.concurrent.ConcurrentHashMap
+
+/**
+ * Progress callback for relay fetch operations
+ */
+data class RelayFetchProgress(
+    val relay: NormalizedRelayUrl,
+    val status: RelayFetchStatus,
+    val eventCount: Int,
+)
+
+enum class RelayFetchStatus {
+    WAITING,
+    RECEIVING,
+    EOSE_RECEIVED,
+    TIMEOUT,
+}
+
+/**
+ * One-shot relay fetch helper for chess events.
+ *
+ * Follows the existing INostrClient + IRequestListener + Channel pattern
+ * from quartz (see NostrClientSingleDownloadExt.kt).
+ *
+ * Each fetch opens a subscription, collects events until EOSE from all relays,
+ * then closes and returns the collected events. The subscription is transient —
+ * no state is cached between fetches.
+ */
+class ChessRelayFetchHelper(
+    private val client: INostrClient,
+) {
+    /**
+     * Fetch events matching filters from relays, waiting for EOSE.
+     *
+     * @param filters Map of relay → filter list (same format as INostrClient.openReqSubscription)
+     * @param timeoutMs Max time to wait for relays to respond (default from ChessConfig)
+     * @param onProgress Optional callback for progress updates per relay
+     * @return Deduplicated list of events received before timeout/EOSE
+     */
+    suspend fun fetchEvents(
+        filters: Map<NormalizedRelayUrl, List<Filter>>,
+        timeoutMs: Long = ChessConfig.FETCH_TIMEOUT_MS,
+        onProgress: ((RelayFetchProgress) -> Unit)? = null,
+    ): List<Event> {
+        if (filters.isEmpty()) return emptyList()
+
+        val events = ConcurrentHashMap<String, Event>()
+        val relayCount = filters.keys.size
+        val eoseReceived = ConcurrentHashMap.newKeySet<NormalizedRelayUrl>()
+        val relayEventCounts = ConcurrentHashMap<NormalizedRelayUrl, Int>()
+        val allEose = CompletableDeferred<Unit>()
+        val subId = newSubId()
+
+        // Initialize all relays as WAITING
+        filters.keys.forEach { relay ->
+            relayEventCounts[relay] = 0
+            onProgress?.invoke(RelayFetchProgress(relay, RelayFetchStatus.WAITING, 0))
+        }
+
+        val listener =
+            object : IRequestListener {
+                override fun onEvent(
+                    event: Event,
+                    isLive: Boolean,
+                    relay: NormalizedRelayUrl,
+                    forFilters: List<Filter>?,
+                ) {
+                    events[event.id] = event
+                    val count = relayEventCounts.compute(relay) { _, v -> (v ?: 0) + 1 } ?: 1
+                    onProgress?.invoke(RelayFetchProgress(relay, RelayFetchStatus.RECEIVING, count))
+                }
+
+                override fun onEose(
+                    relay: NormalizedRelayUrl,
+                    forFilters: List<Filter>?,
+                ) {
+                    eoseReceived.add(relay)
+                    val count = relayEventCounts[relay] ?: 0
+                    onProgress?.invoke(RelayFetchProgress(relay, RelayFetchStatus.EOSE_RECEIVED, count))
+                    // Complete when all relays respond
+                    if (eoseReceived.size >= relayCount) {
+                        allEose.complete(Unit)
+                    }
+                }
+            }
+
+        client.openReqSubscription(subId, filters, listener)
+        val eoseResult = withTimeoutOrNull(timeoutMs) { allEose.await() }
+
+        // Mark timed-out relays
+        if (eoseResult == null) {
+            filters.keys.forEach { relay ->
+                if (relay !in eoseReceived) {
+                    val count = relayEventCounts[relay] ?: 0
+                    onProgress?.invoke(RelayFetchProgress(relay, RelayFetchStatus.TIMEOUT, count))
+                }
+            }
+        }
+
+        client.close(subId)
+
+        return events.values.toList()
+    }
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/ChessSyncBanner.kt

@@ -0,0 +1,311 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import androidx.compose.animation.AnimatedVisibility
+import androidx.compose.animation.animateContentSize
+import androidx.compose.animation.core.animateFloatAsState
+import androidx.compose.animation.core.tween
+import androidx.compose.animation.expandVertically
+import androidx.compose.animation.fadeIn
+import androidx.compose.animation.fadeOut
+import androidx.compose.animation.shrinkVertically
+import androidx.compose.animation.slideInVertically
+import androidx.compose.animation.slideOutVertically
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.CheckCircle
+import androidx.compose.material.icons.filled.CloudDownload
+import androidx.compose.material.icons.filled.Error
+import androidx.compose.material.icons.filled.ExpandLess
+import androidx.compose.material.icons.filled.ExpandMore
+import androidx.compose.material.icons.filled.HourglassEmpty
+import androidx.compose.material.icons.filled.Warning
+import androidx.compose.material3.HorizontalDivider
+import androidx.compose.material3.Icon
+import androidx.compose.material3.LinearProgressIndicator
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.unit.dp
+
+/**
+ * Shared banner showing chess sync/subscription status with expandable relay details.
+ * Shows incoming event progress from relays during refresh.
+ */
+@Composable
+fun ChessSyncBanner(
+    status: ChessSyncStatus,
+    onRetry: () -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    val isVisible = status !is ChessSyncStatus.Idle
+    var isExpanded by remember { mutableStateOf(false) }
+
+    AnimatedVisibility(
+        visible = isVisible,
+        enter = slideInVertically(initialOffsetY = { -it }) + fadeIn(tween(200)),
+        exit = slideOutVertically(targetOffsetY = { -it }) + fadeOut(tween(150)),
+        modifier = modifier,
+    ) {
+        Surface(
+            color = getSyncStatusBackgroundColor(status),
+            tonalElevation = 2.dp,
+            modifier = Modifier.fillMaxWidth(),
+        ) {
+            Column(
+                modifier =
+                    Modifier
+                        .animateContentSize()
+                        .clickable {
+                            if (status is ChessSyncStatus.PartialSync) {
+                                onRetry()
+                            } else {
+                                isExpanded = !isExpanded
+                            }
+                        },
+            ) {
+                // Main status row
+                Row(
+                    verticalAlignment = Alignment.CenterVertically,
+                    horizontalArrangement = Arrangement.spacedBy(8.dp),
+                    modifier = Modifier.padding(horizontal = 16.dp, vertical = 10.dp),
+                ) {
+                    Icon(
+                        imageVector = getSyncStatusIcon(status),
+                        contentDescription = null,
+                        tint = getSyncStatusIconColor(status),
+                        modifier = Modifier.size(18.dp),
+                    )
+
+                    Column(modifier = Modifier.weight(1f)) {
+                        Row(
+                            horizontalArrangement = Arrangement.SpaceBetween,
+                            verticalAlignment = Alignment.CenterVertically,
+                            modifier = Modifier.fillMaxWidth(),
+                        ) {
+                            Text(
+                                text = getSyncStatusText(status),
+                                style = MaterialTheme.typography.bodySmall,
+                                color = MaterialTheme.colorScheme.onSurface,
+                                maxLines = 1,
+                                overflow = TextOverflow.Ellipsis,
+                                modifier = Modifier.weight(1f),
+                            )
+
+                            Spacer(Modifier.width(8.dp))
+
+                            Text(
+                                text = getSyncStatusDetail(status),
+                                style = MaterialTheme.typography.labelMedium,
+                                color = getSyncStatusDetailColor(status),
+                            )
+                        }
+
+                        // Progress bar for syncing
+                        if (status is ChessSyncStatus.Syncing) {
+                            Spacer(Modifier.height(4.dp))
+                            val progress = status.eoseCount.toFloat() / status.totalCount.coerceAtLeast(1)
+                            val animatedProgress by animateFloatAsState(
+                                targetValue = progress,
+                                animationSpec = tween(300),
+                                label = "syncProgress",
+                            )
+                            LinearProgressIndicator(
+                                progress = { animatedProgress },
+                                modifier = Modifier.fillMaxWidth(),
+                                color = MaterialTheme.colorScheme.primary,
+                                trackColor = MaterialTheme.colorScheme.surfaceVariant,
+                            )
+                        }
+                    }
+
+                    // Expand/collapse icon
+                    if (status !is ChessSyncStatus.Idle && getRelayStates(status).isNotEmpty()) {
+                        Icon(
+                            imageVector = if (isExpanded) Icons.Default.ExpandLess else Icons.Default.ExpandMore,
+                            contentDescription = if (isExpanded) "Collapse" else "Expand",
+                            tint = MaterialTheme.colorScheme.onSurfaceVariant,
+                            modifier = Modifier.size(20.dp),
+                        )
+                    }
+                }
+
+                // Expandable relay details
+                AnimatedVisibility(
+                    visible = isExpanded && getRelayStates(status).isNotEmpty(),
+                    enter = expandVertically() + fadeIn(),
+                    exit = shrinkVertically() + fadeOut(),
+                ) {
+                    Column {
+                        HorizontalDivider(
+                            color = MaterialTheme.colorScheme.outlineVariant,
+                            thickness = 0.5.dp,
+                        )
+                        RelayStatusList(
+                            relayStates = getRelayStates(status),
+                            modifier = Modifier.padding(horizontal = 16.dp, vertical = 8.dp),
+                        )
+                    }
+                }
+            }
+        }
+    }
+}
+
+@Composable
+private fun RelayStatusList(
+    relayStates: List<RelaySyncState>,
+    modifier: Modifier = Modifier,
+) {
+    Column(
+        verticalArrangement = Arrangement.spacedBy(4.dp),
+        modifier = modifier,
+    ) {
+        relayStates.forEach { relay ->
+            RelayStatusRow(relay)
+        }
+    }
+}
+
+@Composable
+private fun RelayStatusRow(relay: RelaySyncState) {
+    Row(
+        verticalAlignment = Alignment.CenterVertically,
+        horizontalArrangement = Arrangement.spacedBy(8.dp),
+        modifier = Modifier.fillMaxWidth(),
+    ) {
+        Icon(
+            imageVector = getRelayStatusIcon(relay.status),
+            contentDescription = null,
+            tint = getRelayStatusColor(relay.status),
+            modifier = Modifier.size(14.dp),
+        )
+
+        Text(
+            text = relay.displayName,
+            style = MaterialTheme.typography.labelSmall,
+            color = MaterialTheme.colorScheme.onSurfaceVariant,
+            maxLines = 1,
+            overflow = TextOverflow.Ellipsis,
+            modifier = Modifier.weight(1f),
+        )
+
+        Text(
+            text = "${relay.eventsReceived} events",
+            style = MaterialTheme.typography.labelSmall,
+            color = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.7f),
+        )
+    }
+}
+
+private fun getRelayStates(status: ChessSyncStatus): List<RelaySyncState> =
+    when (status) {
+        is ChessSyncStatus.Syncing -> status.relayStates
+        is ChessSyncStatus.Synced -> status.relayStates
+        is ChessSyncStatus.PartialSync -> status.relayStates
+        is ChessSyncStatus.Idle -> emptyList()
+    }
+
+private fun getRelayStatusIcon(status: RelaySyncStatus): ImageVector =
+    when (status) {
+        RelaySyncStatus.CONNECTING -> Icons.Default.HourglassEmpty
+        RelaySyncStatus.WAITING -> Icons.Default.HourglassEmpty
+        RelaySyncStatus.RECEIVING -> Icons.Default.CloudDownload
+        RelaySyncStatus.EOSE_RECEIVED -> Icons.Default.CheckCircle
+        RelaySyncStatus.FAILED -> Icons.Default.Error
+    }
+
+@Composable
+private fun getRelayStatusColor(status: RelaySyncStatus): Color =
+    when (status) {
+        RelaySyncStatus.CONNECTING -> MaterialTheme.colorScheme.secondary
+        RelaySyncStatus.WAITING -> MaterialTheme.colorScheme.secondary
+        RelaySyncStatus.RECEIVING -> MaterialTheme.colorScheme.primary
+        RelaySyncStatus.EOSE_RECEIVED -> MaterialTheme.colorScheme.primary
+        RelaySyncStatus.FAILED -> MaterialTheme.colorScheme.error
+    }
+
+@Composable
+private fun getSyncStatusBackgroundColor(status: ChessSyncStatus): Color =
+    when (status) {
+        is ChessSyncStatus.PartialSync -> MaterialTheme.colorScheme.errorContainer.copy(alpha = 0.7f)
+        is ChessSyncStatus.Synced -> MaterialTheme.colorScheme.primaryContainer.copy(alpha = 0.7f)
+        else -> MaterialTheme.colorScheme.surfaceContainer
+    }
+
+private fun getSyncStatusIcon(status: ChessSyncStatus): ImageVector =
+    when (status) {
+        is ChessSyncStatus.Syncing -> Icons.Default.CloudDownload
+        is ChessSyncStatus.Synced -> Icons.Default.CheckCircle
+        is ChessSyncStatus.PartialSync -> Icons.Default.Warning
+        is ChessSyncStatus.Idle -> Icons.Default.CheckCircle
+    }
+
+@Composable
+private fun getSyncStatusIconColor(status: ChessSyncStatus): Color =
+    when (status) {
+        is ChessSyncStatus.PartialSync -> MaterialTheme.colorScheme.error
+        is ChessSyncStatus.Synced -> MaterialTheme.colorScheme.primary
+        else -> MaterialTheme.colorScheme.primary
+    }
+
+private fun getSyncStatusText(status: ChessSyncStatus): String =
+    when (status) {
+        is ChessSyncStatus.Syncing -> "Syncing ${status.phase}..."
+        is ChessSyncStatus.Synced -> "Synced"
+        is ChessSyncStatus.PartialSync -> status.message
+        is ChessSyncStatus.Idle -> ""
+    }
+
+private fun getSyncStatusDetail(status: ChessSyncStatus): String =
+    when (status) {
+        is ChessSyncStatus.Syncing -> "${status.eoseCount}/${status.totalCount} relays • ${status.totalEventsReceived} events"
+        is ChessSyncStatus.Synced -> "${status.successCount}/${status.totalCount} relays • ${status.challengeCount} challenges • ${status.gameCount} games"
+        is ChessSyncStatus.PartialSync -> "Tap to retry"
+        is ChessSyncStatus.Idle -> ""
+    }
+
+@Composable
+private fun getSyncStatusDetailColor(status: ChessSyncStatus): Color =
+    when (status) {
+        is ChessSyncStatus.PartialSync -> MaterialTheme.colorScheme.error
+        else -> MaterialTheme.colorScheme.primary
+    }

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/IUserMetadataProvider.kt

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+/**
+ * Platform-specific metadata provider for enriching chess challenges with display info.
+ *
+ * Android: wraps LocalCache.users[pubkey].info
+ * Desktop: wraps UserMetadataCache
+ */
+interface IUserMetadataProvider {
+    fun getDisplayName(pubkey: String): String
+
+    fun getPictureUrl(pubkey: String): String?
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/InteractiveChessBoard.kt

@@ -0,0 +1,394 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import androidx.compose.foundation.Image
+import androidx.compose.foundation.background
+import androidx.compose.foundation.border
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material3.Card
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.alpha
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
+import com.vitorpamplona.quartz.nip64Chess.ChessEngine
+import com.vitorpamplona.quartz.nip64Chess.ChessPiece
+import com.vitorpamplona.quartz.nip64Chess.PieceType
+import com.vitorpamplona.quartz.nip64Chess.Color as ChessColor
+
+/**
+ * Interactive chess board that allows piece selection and moves
+ *
+ * @param engine Chess engine for move validation and legal moves
+ * @param modifier Modifier for the board
+ * @param boardSize Total size of the board in dp
+ * @param flipped If true, renders from black's perspective (rank 1 at top)
+ * @param playerColor The color the player is playing as (only allows moving these pieces)
+ * @param isSpectator If true, disables all interaction (spectator/watch mode)
+ * @param onMoveMade Callback when a valid move is made, receives (from, to, san)
+ *                   NOTE: This callback should make the actual move - this component only validates
+ */
+@Composable
+fun InteractiveChessBoard(
+    engine: ChessEngine,
+    modifier: Modifier = Modifier,
+    boardSize: Dp = 400.dp,
+    flipped: Boolean = false,
+    playerColor: ChessColor? = null, // null = allow both (for local play)
+    isSpectator: Boolean = false,
+    positionVersion: Int = 0, // External trigger for position refresh (e.g. moveHistory.size)
+    onMoveMade: (from: String, to: String, san: String) -> Unit = { _, _, _ -> },
+) {
+    // Track local move count + external version to trigger recomposition when board changes
+    var localMoveCount by remember { mutableStateOf(0) }
+    val effectiveVersion = localMoveCount + positionVersion
+    val position = remember(engine, effectiveVersion) { engine.getPosition() }
+    val sideToMove = remember(engine, effectiveVersion) { engine.getSideToMove() }
+    var selectedSquare by remember { mutableStateOf<Pair<Int, Int>?>(null) }
+    var legalMoves by remember { mutableStateOf<List<String>>(emptyList()) }
+
+    // Pawn promotion state
+    var pendingPromotion by remember { mutableStateOf<PendingPromotion?>(null) }
+
+    // Clear stale selection when position changes externally (e.g. opponent move)
+    LaunchedEffect(positionVersion) {
+        selectedSquare = null
+        legalMoves = emptyList()
+        pendingPromotion = null
+    }
+
+    // Can only interact if not spectating and it's your turn (or playerColor is null for local play)
+    val canInteract = !isSpectator && (playerColor == null || sideToMove == playerColor)
+
+    val squareSize = boardSize / 8
+
+    // Rank iteration order based on perspective
+    val rankRange = if (flipped) (0..7) else (7 downTo 0)
+    val fileRange = if (flipped) (7 downTo 0) else (0..7)
+
+    Box(modifier = modifier.size(boardSize)) {
+        Column(modifier = Modifier.fillMaxSize()) {
+            for (rank in rankRange) {
+                Row {
+                    for (file in fileRange) {
+                        val piece = position.pieceAt(file, rank)
+                        val isLightSquare = (rank + file) % 2 == 0
+                        val square = fileRankToSquare(file, rank)
+                        val isSelected = selectedSquare == (file to rank)
+                        val isLegalMove = legalMoves.contains(square)
+
+                        val showCoord = if (flipped) rank == 7 else rank == 0
+
+                        InteractiveChessSquare(
+                            piece = piece,
+                            isLight = isLightSquare,
+                            size = squareSize,
+                            isSelected = isSelected,
+                            isLegalMove = isLegalMove,
+                            showCoordinate = showCoord,
+                            file = file,
+                            rank = rank,
+                            onClick = {
+                                if (!canInteract || pendingPromotion != null) return@InteractiveChessSquare
+
+                                if (selectedSquare != null) {
+                                    // Attempt to make move - validate first, don't actually make it
+                                    val from = fileRankToSquare(selectedSquare!!.first, selectedSquare!!.second)
+                                    val to = square
+
+                                    if (legalMoves.contains(to)) {
+                                        // Check if this is a pawn promotion move
+                                        val fromRank = selectedSquare!!.second
+                                        val toRank = rank
+                                        val movingPiece = position.pieceAt(selectedSquare!!.first, fromRank)
+                                        val isPromotion =
+                                            movingPiece?.type == PieceType.PAWN &&
+                                                (toRank == 7 || toRank == 0)
+
+                                        if (isPromotion) {
+                                            // Show promotion dialog
+                                            pendingPromotion =
+                                                PendingPromotion(
+                                                    from = from,
+                                                    to = to,
+                                                    file = file,
+                                                    rank = toRank,
+                                                    color = sideToMove,
+                                                )
+                                        } else {
+                                            // Valid move - callback will make the actual move
+                                            selectedSquare = null
+                                            legalMoves = emptyList()
+                                            // Pass empty san - callback will get it from makeMove result
+                                            onMoveMade(from, to, "")
+                                            localMoveCount++ // Trigger recomposition after move is made
+                                        }
+                                    } else {
+                                        // Not a legal move target - try selecting this square instead
+                                        val validColor = playerColor ?: sideToMove
+                                        if (piece != null && piece.color == validColor) {
+                                            selectedSquare = file to rank
+                                            legalMoves = engine.getLegalMovesFrom(square)
+                                        } else {
+                                            selectedSquare = null
+                                            legalMoves = emptyList()
+                                        }
+                                    }
+                                } else {
+                                    // Select piece - only allow selecting player's pieces
+                                    val validColor = playerColor ?: sideToMove
+                                    if (piece != null && piece.color == validColor) {
+                                        selectedSquare = file to rank
+                                        legalMoves = engine.getLegalMovesFrom(square)
+                                    }
+                                }
+                            },
+                        )
+                    }
+                }
+            }
+        }
+
+        // Promotion dialog overlay
+        pendingPromotion?.let { promo ->
+            PromotionPicker(
+                color = promo.color,
+                squareSize = squareSize,
+                onPieceSelected = { pieceType ->
+                    // Make the move with promotion
+                    val promotionSuffix =
+                        when (pieceType) {
+                            PieceType.QUEEN -> "q"
+                            PieceType.ROOK -> "r"
+                            PieceType.BISHOP -> "b"
+                            PieceType.KNIGHT -> "n"
+                            else -> "q"
+                        }
+                    selectedSquare = null
+                    legalMoves = emptyList()
+                    pendingPromotion = null
+                    // Include promotion in the 'to' square for the callback
+                    onMoveMade(promo.from, promo.to + promotionSuffix, "")
+                    localMoveCount++
+                },
+                onDismiss = {
+                    pendingPromotion = null
+                    selectedSquare = null
+                    legalMoves = emptyList()
+                },
+            )
+        }
+    }
+}
+
+/**
+ * Single interactive chess square
+ */
+@Composable
+private fun InteractiveChessSquare(
+    piece: com.vitorpamplona.quartz.nip64Chess.ChessPiece?,
+    isLight: Boolean,
+    size: Dp,
+    isSelected: Boolean,
+    isLegalMove: Boolean,
+    showCoordinate: Boolean,
+    file: Int,
+    rank: Int,
+    onClick: () -> Unit,
+) {
+    val backgroundColor =
+        when {
+            isSelected -> Color(0xFF7FA650)
+            isLegalMove -> Color(0xFFAAC75B).copy(alpha = 0.6f)
+            isLight -> Color(0xFFF0D9B5)
+            else -> Color(0xFFB58863)
+        }
+
+    Box(
+        modifier =
+            Modifier
+                .size(size)
+                .background(backgroundColor)
+                .clickable { onClick() }
+                .let {
+                    if (isSelected) {
+                        it.border(2.dp, Color(0xFF4A7536))
+                    } else {
+                        it
+                    }
+                },
+        contentAlignment = Alignment.Center,
+    ) {
+        // Display piece using CBurnett ImageVector icons
+        piece?.let {
+            Image(
+                imageVector = it.toImageVector(),
+                contentDescription = "${it.color} ${it.type}",
+                modifier = Modifier.fillMaxSize().padding(2.dp),
+            )
+        }
+
+        // Show legal move indicator
+        if (isLegalMove && piece == null) {
+            Box(
+                modifier =
+                    Modifier
+                        .size(size * 0.25f)
+                        .background(Color(0xFF7FA650), CircleShape)
+                        .alpha(0.5f),
+            )
+        } else if (isLegalMove && piece != null) {
+            // Capture indicator - ring around piece
+            Box(
+                modifier =
+                    Modifier
+                        .size(size * 0.8f)
+                        .border(3.dp, Color(0xFF7FA650).copy(alpha = 0.5f), CircleShape),
+            )
+        }
+
+        // Show file coordinate (a-h) on bottom rank
+        if (showCoordinate) {
+            Text(
+                text = ('a' + file).toString(),
+                fontSize = 10.sp,
+                fontWeight = FontWeight.Bold,
+                color = if (isLight) Color(0xFFB58863) else Color(0xFFF0D9B5),
+                modifier =
+                    Modifier
+                        .align(Alignment.BottomEnd)
+                        .padding(2.dp),
+            )
+        }
+    }
+}
+
+/**
+ * Convert file/rank to algebraic notation (e.g., 0,0 -> "a1")
+ */
+private fun fileRankToSquare(
+    file: Int,
+    rank: Int,
+): String = "${('a' + file)}${rank + 1}"
+
+/**
+ * Extension function to convert ChessPiece to CBurnett ImageVector
+ */
+private fun ChessPiece.toImageVector(): ImageVector {
+    val white = color == ChessColor.WHITE
+    return when (type) {
+        PieceType.KING -> if (white) ChessPieceVectors.WhiteKing else ChessPieceVectors.BlackKing
+        PieceType.QUEEN -> if (white) ChessPieceVectors.WhiteQueen else ChessPieceVectors.BlackQueen
+        PieceType.ROOK -> if (white) ChessPieceVectors.WhiteRook else ChessPieceVectors.BlackRook
+        PieceType.BISHOP -> if (white) ChessPieceVectors.WhiteBishop else ChessPieceVectors.BlackBishop
+        PieceType.KNIGHT -> if (white) ChessPieceVectors.WhiteKnight else ChessPieceVectors.BlackKnight
+        PieceType.PAWN -> if (white) ChessPieceVectors.WhitePawn else ChessPieceVectors.BlackPawn
+    }
+}
+
+/**
+ * Data class for pending pawn promotion
+ */
+private data class PendingPromotion(
+    val from: String,
+    val to: String,
+    val file: Int,
+    val rank: Int,
+    val color: ChessColor,
+)
+
+/**
+ * Promotion piece picker overlay
+ */
+@Composable
+private fun PromotionPicker(
+    color: ChessColor,
+    squareSize: Dp,
+    onPieceSelected: (PieceType) -> Unit,
+    onDismiss: () -> Unit,
+) {
+    val isWhite = color == ChessColor.WHITE
+    val promotionPieces =
+        listOf(
+            PieceType.QUEEN to if (isWhite) ChessPieceVectors.WhiteQueen else ChessPieceVectors.BlackQueen,
+            PieceType.ROOK to if (isWhite) ChessPieceVectors.WhiteRook else ChessPieceVectors.BlackRook,
+            PieceType.BISHOP to if (isWhite) ChessPieceVectors.WhiteBishop else ChessPieceVectors.BlackBishop,
+            PieceType.KNIGHT to if (isWhite) ChessPieceVectors.WhiteKnight else ChessPieceVectors.BlackKnight,
+        )
+
+    // Semi-transparent overlay
+    Box(
+        modifier =
+            Modifier
+                .fillMaxSize()
+                .background(Color.Black.copy(alpha = 0.5f))
+                .clickable { onDismiss() },
+        contentAlignment = Alignment.Center,
+    ) {
+        Card(
+            shape = RoundedCornerShape(8.dp),
+            modifier = Modifier.clickable { /* prevent dismiss */ },
+        ) {
+            Row(
+                modifier = Modifier.padding(8.dp),
+                horizontalArrangement = Arrangement.spacedBy(4.dp),
+            ) {
+                promotionPieces.forEach { (pieceType, icon) ->
+                    Box(
+                        modifier =
+                            Modifier
+                                .size(squareSize)
+                                .background(Color(0xFFF0D9B5), RoundedCornerShape(4.dp))
+                                .clickable { onPieceSelected(pieceType) },
+                        contentAlignment = Alignment.Center,
+                    ) {
+                        Image(
+                            imageVector = icon,
+                            contentDescription = pieceType.name,
+                            modifier = Modifier.fillMaxSize().padding(4.dp),
+                        )
+                    }
+                }
+            }
+        }
+    }
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/LiveChessGame.kt

@@ -0,0 +1,927 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import androidx.compose.animation.AnimatedVisibility
+import androidx.compose.animation.core.tween
+import androidx.compose.animation.fadeIn
+import androidx.compose.animation.scaleIn
+import androidx.compose.foundation.background
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.horizontalScroll
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.BoxWithConstraints
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material3.Button
+import androidx.compose.material3.Card
+import androidx.compose.material3.CardDefaults
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedButton
+import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.alpha
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.min
+import androidx.compose.ui.unit.sp
+import androidx.compose.ui.window.Dialog
+import com.vitorpamplona.quartz.nip64Chess.ChessEngine
+import com.vitorpamplona.quartz.nip64Chess.ChessGameNameGenerator
+import com.vitorpamplona.quartz.nip64Chess.Color
+import com.vitorpamplona.quartz.nip64Chess.GameResult
+import com.vitorpamplona.quartz.nip64Chess.GameStatus
+import com.vitorpamplona.quartz.nip64Chess.LiveChessGameState
+import androidx.compose.ui.graphics.Color as ComposeColor
+
+/**
+ * Dialog for creating a new chess game challenge
+ *
+ * @param onDismiss Callback when dialog is dismissed
+ * @param onCreateGame Callback when game is created (opponentPubkey, playerColor)
+ */
+@Composable
+fun NewChessGameDialog(
+    onDismiss: () -> Unit,
+    onCreateGame: (opponentPubkey: String?, playerColor: Color) -> Unit,
+) {
+    var opponentPubkey by remember { mutableStateOf("") }
+    var selectedColor by remember { mutableStateOf(Color.WHITE) }
+
+    Dialog(onDismissRequest = onDismiss) {
+        Card(
+            modifier =
+                Modifier
+                    .fillMaxWidth()
+                    .padding(16.dp),
+        ) {
+            Column(
+                modifier = Modifier.padding(16.dp),
+                verticalArrangement = Arrangement.spacedBy(12.dp),
+            ) {
+                Text(
+                    text = "New Chess Game",
+                    style = MaterialTheme.typography.headlineSmall,
+                    fontWeight = FontWeight.Bold,
+                )
+
+                Text(
+                    text = "Create a new chess game challenge",
+                    style = MaterialTheme.typography.bodyMedium,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                )
+
+                Spacer(modifier = Modifier.height(8.dp))
+
+                OutlinedTextField(
+                    value = opponentPubkey,
+                    onValueChange = { opponentPubkey = it },
+                    label = { Text("Opponent npub (optional)") },
+                    placeholder = { Text("Leave blank for open challenge") },
+                    modifier = Modifier.fillMaxWidth(),
+                    singleLine = true,
+                )
+
+                Text(
+                    text = "Your color:",
+                    style = MaterialTheme.typography.labelMedium,
+                )
+
+                Row(
+                    modifier = Modifier.fillMaxWidth(),
+                    horizontalArrangement = Arrangement.spacedBy(8.dp),
+                ) {
+                    OutlinedButton(
+                        onClick = { selectedColor = Color.WHITE },
+                        modifier = Modifier.weight(1f),
+                    ) {
+                        Text(
+                            text = if (selectedColor == Color.WHITE) "✓ White" else "White",
+                            fontWeight = if (selectedColor == Color.WHITE) FontWeight.Bold else FontWeight.Normal,
+                        )
+                    }
+
+                    OutlinedButton(
+                        onClick = { selectedColor = Color.BLACK },
+                        modifier = Modifier.weight(1f),
+                    ) {
+                        Text(
+                            text = if (selectedColor == Color.BLACK) "✓ Black" else "Black",
+                            fontWeight = if (selectedColor == Color.BLACK) FontWeight.Bold else FontWeight.Normal,
+                        )
+                    }
+                }
+
+                Spacer(modifier = Modifier.height(8.dp))
+
+                Row(
+                    modifier = Modifier.fillMaxWidth(),
+                    horizontalArrangement = Arrangement.End,
+                ) {
+                    OutlinedButton(onClick = onDismiss) {
+                        Text("Cancel")
+                    }
+
+                    Spacer(modifier = Modifier.width(8.dp))
+
+                    Button(
+                        onClick = {
+                            onCreateGame(
+                                opponentPubkey.ifBlank { null },
+                                selectedColor,
+                            )
+                        },
+                    ) {
+                        Text("Create Game")
+                    }
+                }
+            }
+        }
+    }
+}
+
+/**
+ * Complete live chess game UI with board, controls, and game info
+ *
+ * This version observes LiveChessGameState flows for automatic UI updates
+ * when polling refreshes the game state.
+ *
+ * @param modifier Modifier for the root layout
+ * @param gameState Live chess game state (observed for updates)
+ * @param opponentName Opponent's display name
+ * @param onMoveMade Callback when player makes a move (from, to, san)
+ * @param onResign Callback when player resigns
+ * @param isSpectatorOverride If non-null, overrides gameState.isSpectator. Use this when
+ *        spectator status is determined by which map the game is in (activeGames vs spectatingGames)
+ *        rather than the potentially stale isSpectator flag from relay reconstruction.
+ */
+@Composable
+fun LiveChessGameScreen(
+    modifier: Modifier = Modifier,
+    gameState: LiveChessGameState,
+    opponentName: String,
+    onMoveMade: (from: String, to: String, san: String) -> Unit,
+    onResign: () -> Unit,
+    isSpectatorOverride: Boolean? = null,
+    onGameEndDismiss: (() -> Unit)? = null,
+) {
+    // Observe state flows for automatic recomposition on updates
+    val currentPosition by gameState.currentPosition.collectAsState()
+    val moveHistory by gameState.moveHistory.collectAsState()
+    val gameStatus by gameState.gameStatus.collectAsState()
+
+    // Use override if provided, otherwise fall back to gameState flag
+    val isSpectator = isSpectatorOverride ?: gameState.isSpectator
+
+    // Pending challenges and spectators cannot make moves
+    val canMakeMoves = !isSpectator && !gameState.isPendingChallenge
+
+    // Track if game end overlay was dismissed
+    var gameEndDismissed by remember { mutableStateOf(false) }
+
+    Box(modifier = modifier.fillMaxSize()) {
+        BoxWithConstraints(
+            modifier = Modifier.fillMaxSize(),
+        ) {
+            // Calculate board size dynamically based on available space
+            // Use a percentage of available height to leave room for other UI elements
+            val availableWidth = maxWidth - 32.dp // Account for horizontal padding
+            // Reserve ~35% of height for header, history, controls, and any banners
+            val availableHeight = maxHeight * 0.65f
+            val boardSize = min(availableWidth, availableHeight).coerceIn(150.dp, 520.dp)
+
+            Column(
+                modifier =
+                    Modifier
+                        .fillMaxSize()
+                        .padding(16.dp),
+                horizontalAlignment = Alignment.CenterHorizontally,
+                verticalArrangement = Arrangement.spacedBy(8.dp),
+            ) {
+                // Game info - use currentPosition.activeColor for turn display
+                GameInfoHeader(
+                    gameId = gameState.gameId,
+                    opponentName = opponentName,
+                    playerColor = gameState.playerColor,
+                    currentTurn = currentPosition.activeColor,
+                    isSpectator = isSpectator,
+                    isPendingChallenge = gameState.isPendingChallenge,
+                    gameStatus = gameStatus,
+                )
+
+                // Interactive chess board - flip when playing black (spectators see from white's view)
+                // Auto-sized to fit available space
+                InteractiveChessBoard(
+                    engine = gameState.engine,
+                    boardSize = boardSize,
+                    flipped = !isSpectator && gameState.playerColor == Color.BLACK,
+                    playerColor = gameState.playerColor,
+                    isSpectator = !canMakeMoves,
+                    positionVersion = moveHistory.size,
+                    onMoveMade = onMoveMade,
+                )
+
+                // Move history (scrollable) - observed from state flow
+                MoveHistoryDisplay(
+                    moves = moveHistory,
+                )
+
+                // Show appropriate controls based on game state
+                when {
+                    gameStatus is GameStatus.Finished -> {
+                        GameEndInfo(
+                            result = (gameStatus as GameStatus.Finished).result,
+                            playerColor = gameState.playerColor,
+                            isSpectator = isSpectator,
+                        )
+                    }
+
+                    gameState.isPendingChallenge -> {
+                        PendingChallengeInfo()
+                    }
+
+                    isSpectator -> {
+                        SpectatorInfo()
+                    }
+
+                    else -> {
+                        GameControls(onResign = onResign)
+                    }
+                }
+            }
+        }
+
+        // Game end celebration overlay
+        if (gameStatus is GameStatus.Finished && !gameEndDismissed) {
+            GameEndOverlay(
+                result = (gameStatus as GameStatus.Finished).result,
+                playerColor = gameState.playerColor,
+                isSpectator = isSpectator,
+                onDismiss = {
+                    gameEndDismissed = true
+                    onGameEndDismiss?.invoke()
+                },
+            )
+        }
+    }
+}
+
+/**
+ * Legacy version that takes engine directly (for backwards compatibility)
+ *
+ * @param modifier Modifier for the root layout
+ * @param engine Chess engine instance
+ * @param playerColor Color the player is playing as
+ * @param gameId Unique game identifier
+ * @param opponentName Opponent's display name
+ * @param onMoveMade Callback when player makes a move (from, to, san)
+ * @param onResign Callback when player resigns
+ */
+@Composable
+fun LiveChessGameScreen(
+    modifier: Modifier = Modifier,
+    engine: ChessEngine,
+    playerColor: Color,
+    gameId: String,
+    opponentName: String,
+    onMoveMade: (from: String, to: String, san: String) -> Unit,
+    onResign: () -> Unit,
+) {
+    BoxWithConstraints(
+        modifier = modifier.fillMaxSize(),
+    ) {
+        // Calculate board size based on available space
+        // Leave room for header (~100dp), history (~60dp), controls (~60dp), and padding
+        val availableWidth = maxWidth - 32.dp // Account for horizontal padding
+        val availableHeight = maxHeight - 250.dp // Account for other UI elements
+        val boardSize = min(availableWidth, availableHeight).coerceAtLeast(200.dp)
+
+        Column(
+            modifier =
+                Modifier
+                    .fillMaxSize()
+                    .padding(16.dp),
+            horizontalAlignment = Alignment.CenterHorizontally,
+            verticalArrangement = Arrangement.spacedBy(12.dp),
+        ) {
+            // Game info
+            GameInfoHeader(
+                gameId = gameId,
+                opponentName = opponentName,
+                playerColor = playerColor,
+                currentTurn = engine.getSideToMove(),
+            )
+
+            // Interactive chess board - flip when playing black
+            // Auto-sized to fit available space
+            InteractiveChessBoard(
+                engine = engine,
+                boardSize = boardSize,
+                flipped = playerColor == Color.BLACK,
+                positionVersion = engine.getMoveHistory().size,
+                onMoveMade = onMoveMade,
+            )
+
+            // Move history (scrollable)
+            MoveHistoryDisplay(
+                moves = engine.getMoveHistory(),
+            )
+
+            // Game controls
+            GameControls(
+                onResign = onResign,
+            )
+        }
+    }
+}
+
+/**
+ * Game information header showing game ID, opponent, and current turn
+ */
+@Composable
+private fun GameInfoHeader(
+    gameId: String,
+    opponentName: String,
+    playerColor: Color,
+    currentTurn: Color,
+    isSpectator: Boolean = false,
+    isPendingChallenge: Boolean = false,
+    gameStatus: GameStatus = GameStatus.InProgress,
+) {
+    // Extract human-readable game name if available
+    val gameName =
+        remember(gameId) {
+            ChessGameNameGenerator.extractDisplayName(gameId)
+        }
+
+    Column(
+        modifier = Modifier.fillMaxWidth(),
+        horizontalAlignment = Alignment.CenterHorizontally,
+    ) {
+        // Show readable name prominently if available
+        if (gameName != null) {
+            Text(
+                text = gameName,
+                style = MaterialTheme.typography.titleMedium,
+                fontWeight = FontWeight.Bold,
+                color = MaterialTheme.colorScheme.primary,
+            )
+        }
+
+        Text(
+            text = if (gameName != null) gameId.take(16) else "Game: ${gameId.take(8)}...",
+            style = MaterialTheme.typography.labelSmall,
+            color = MaterialTheme.colorScheme.onSurfaceVariant,
+        )
+
+        when {
+            isPendingChallenge -> {
+                Text(
+                    text = "Challenge Pending",
+                    style = MaterialTheme.typography.titleMedium,
+                    fontWeight = FontWeight.Bold,
+                    color = MaterialTheme.colorScheme.secondary,
+                )
+
+                Text(
+                    text = "You are playing ${if (playerColor == Color.WHITE) "White" else "Black"}",
+                    style = MaterialTheme.typography.bodyMedium,
+                )
+
+                Text(
+                    text = if (opponentName.isNotEmpty()) "Waiting for $opponentName" else "Open challenge",
+                    style = MaterialTheme.typography.bodyMedium,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                )
+            }
+
+            isSpectator -> {
+                Text(
+                    text = "Spectating",
+                    style = MaterialTheme.typography.titleMedium,
+                    fontWeight = FontWeight.Bold,
+                    color = MaterialTheme.colorScheme.tertiary,
+                )
+
+                val turnText = "${if (currentTurn == Color.WHITE) "White" else "Black"}'s turn"
+                Text(
+                    text = turnText,
+                    style = MaterialTheme.typography.bodyMedium,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                )
+            }
+
+            else -> {
+                Text(
+                    text = "vs $opponentName",
+                    style = MaterialTheme.typography.titleMedium,
+                    fontWeight = FontWeight.Bold,
+                )
+
+                Text(
+                    text = "You are playing ${if (playerColor == Color.WHITE) "White" else "Black"}",
+                    style = MaterialTheme.typography.bodyMedium,
+                )
+
+                // Show turn or game result
+                when (gameStatus) {
+                    is GameStatus.Finished -> {
+                        val result = (gameStatus as GameStatus.Finished).result
+                        val resultText =
+                            when {
+                                result == GameResult.DRAW -> "Draw"
+
+                                (result == GameResult.WHITE_WINS && playerColor == Color.WHITE) ||
+                                    (result == GameResult.BLACK_WINS && playerColor == Color.BLACK) -> "You won!"
+
+                                else -> "You lost"
+                            }
+                        val resultColor =
+                            when {
+                                result == GameResult.DRAW -> {
+                                    MaterialTheme.colorScheme.secondary
+                                }
+
+                                (result == GameResult.WHITE_WINS && playerColor == Color.WHITE) ||
+                                    (result == GameResult.BLACK_WINS && playerColor == Color.BLACK) -> {
+                                    ComposeColor(0xFF4CAF50)
+                                }
+
+                                else -> {
+                                    MaterialTheme.colorScheme.error
+                                }
+                            }
+                        Text(
+                            text = resultText,
+                            style = MaterialTheme.typography.bodyMedium,
+                            color = resultColor,
+                            fontWeight = FontWeight.Bold,
+                        )
+                    }
+
+                    else -> {
+                        val turnText =
+                            if (currentTurn == playerColor) {
+                                "Your turn"
+                            } else {
+                                "Opponent's turn"
+                            }
+
+                        Text(
+                            text = turnText,
+                            style = MaterialTheme.typography.bodyMedium,
+                            color =
+                                if (currentTurn == playerColor) {
+                                    MaterialTheme.colorScheme.primary
+                                } else {
+                                    MaterialTheme.colorScheme.onSurfaceVariant
+                                },
+                            fontWeight = if (currentTurn == playerColor) FontWeight.Bold else FontWeight.Normal,
+                        )
+                    }
+                }
+            }
+        }
+    }
+}
+
+/**
+ * Info banner shown when spectating a game
+ */
+@Composable
+private fun SpectatorInfo() {
+    Box(
+        modifier =
+            Modifier
+                .fillMaxWidth()
+                .background(
+                    MaterialTheme.colorScheme.tertiaryContainer.copy(alpha = 0.5f),
+                    RoundedCornerShape(8.dp),
+                ).padding(12.dp),
+        contentAlignment = Alignment.Center,
+    ) {
+        Text(
+            text = "Watching game - spectator mode",
+            style = MaterialTheme.typography.bodyMedium,
+            color = MaterialTheme.colorScheme.onTertiaryContainer,
+        )
+    }
+}
+
+/**
+ * Info banner shown when viewing a pending challenge
+ */
+@Composable
+private fun PendingChallengeInfo() {
+    Box(
+        modifier =
+            Modifier
+                .fillMaxWidth()
+                .background(
+                    MaterialTheme.colorScheme.secondaryContainer.copy(alpha = 0.5f),
+                    RoundedCornerShape(8.dp),
+                ).padding(12.dp),
+        contentAlignment = Alignment.Center,
+    ) {
+        Text(
+            text = "Waiting for opponent to accept challenge",
+            style = MaterialTheme.typography.bodyMedium,
+            color = MaterialTheme.colorScheme.onSecondaryContainer,
+        )
+    }
+}
+
+/**
+ * Display move history in SAN notation with move numbers
+ * Shows in a horizontally scrollable container
+ */
+@Composable
+private fun MoveHistoryDisplay(moves: List<String>) {
+    Column(
+        modifier = Modifier.fillMaxWidth(),
+    ) {
+        Text(
+            text = "Move History",
+            style = MaterialTheme.typography.labelMedium,
+            fontWeight = FontWeight.Bold,
+            modifier = Modifier.padding(bottom = 4.dp),
+        )
+
+        Box(
+            modifier =
+                Modifier
+                    .fillMaxWidth()
+                    .height(48.dp)
+                    .background(
+                        MaterialTheme.colorScheme.surfaceVariant.copy(alpha = 0.5f),
+                        RoundedCornerShape(8.dp),
+                    ).padding(horizontal = 8.dp, vertical = 4.dp),
+        ) {
+            if (moves.isEmpty()) {
+                Text(
+                    text = "No moves yet",
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                    modifier = Modifier.align(Alignment.CenterStart),
+                )
+            } else {
+                val scrollState = rememberScrollState()
+
+                Row(
+                    modifier =
+                        Modifier
+                            .horizontalScroll(scrollState)
+                            .align(Alignment.CenterStart),
+                    horizontalArrangement = Arrangement.spacedBy(4.dp),
+                    verticalAlignment = Alignment.CenterVertically,
+                ) {
+                    // Group moves into pairs (white, black)
+                    moves.chunked(2).forEachIndexed { index, movePair ->
+                        // Move number
+                        Text(
+                            text = "${index + 1}.",
+                            style = MaterialTheme.typography.bodySmall,
+                            fontWeight = FontWeight.Bold,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant,
+                        )
+
+                        // White's move
+                        Text(
+                            text = movePair[0],
+                            style = MaterialTheme.typography.bodySmall,
+                            color = MaterialTheme.colorScheme.onSurface,
+                            modifier =
+                                Modifier
+                                    .background(
+                                        MaterialTheme.colorScheme.surface,
+                                        RoundedCornerShape(4.dp),
+                                    ).padding(horizontal = 4.dp, vertical = 2.dp),
+                        )
+
+                        // Black's move (if exists)
+                        if (movePair.size > 1) {
+                            Text(
+                                text = movePair[1],
+                                style = MaterialTheme.typography.bodySmall,
+                                color = MaterialTheme.colorScheme.onSurface,
+                                modifier =
+                                    Modifier
+                                        .background(
+                                            MaterialTheme.colorScheme.surfaceVariant,
+                                            RoundedCornerShape(4.dp),
+                                        ).padding(horizontal = 4.dp, vertical = 2.dp),
+                            )
+                        }
+
+                        Spacer(modifier = Modifier.width(8.dp))
+                    }
+                }
+            }
+        }
+    }
+}
+
+/**
+ * Game control buttons (Resign)
+ * Note: Draw offers not supported in Jester protocol
+ */
+@Composable
+private fun GameControls(onResign: () -> Unit) {
+    Row(
+        modifier = Modifier.fillMaxWidth(),
+        horizontalArrangement = Arrangement.spacedBy(8.dp, Alignment.CenterHorizontally),
+    ) {
+        OutlinedButton(onClick = onResign) {
+            Text("Resign")
+        }
+    }
+}
+
+/**
+ * Game end celebration overlay
+ */
+@Composable
+private fun GameEndOverlay(
+    result: GameResult,
+    playerColor: Color,
+    isSpectator: Boolean,
+    onDismiss: () -> Unit,
+) {
+    val playerWon =
+        when (result) {
+            GameResult.WHITE_WINS -> playerColor == Color.WHITE
+            GameResult.BLACK_WINS -> playerColor == Color.BLACK
+            GameResult.DRAW, GameResult.IN_PROGRESS -> false
+        }
+
+    val isDraw = result == GameResult.DRAW
+
+    // Determine display based on result
+    val (emoji, title, subtitle, backgroundColor) =
+        when {
+            isSpectator -> {
+                val winnerText =
+                    when (result) {
+                        GameResult.WHITE_WINS -> "White wins!"
+                        GameResult.BLACK_WINS -> "Black wins!"
+                        GameResult.DRAW -> "Draw!"
+                        GameResult.IN_PROGRESS -> "Game Over"
+                    }
+                Quadruple("", "Game Over", winnerText, MaterialTheme.colorScheme.surfaceVariant)
+            }
+
+            playerWon -> {
+                Quadruple(
+                    "",
+                    "Victory!",
+                    "Congratulations!",
+                    ComposeColor(0xFF4CAF50).copy(alpha = 0.95f),
+                )
+            }
+
+            isDraw -> {
+                Quadruple(
+                    "",
+                    "Draw",
+                    "Game ended in a draw",
+                    MaterialTheme.colorScheme.surfaceVariant,
+                )
+            }
+
+            else -> {
+                Quadruple(
+                    "",
+                    "Defeat",
+                    "Better luck next time!",
+                    ComposeColor(0xFFE57373).copy(alpha = 0.95f),
+                )
+            }
+        }
+
+    // Animated visibility
+    AnimatedVisibility(
+        visible = true,
+        enter = fadeIn(animationSpec = tween(300)) + scaleIn(animationSpec = tween(300)),
+    ) {
+        Box(
+            modifier =
+                Modifier
+                    .fillMaxSize()
+                    .background(ComposeColor.Black.copy(alpha = 0.7f))
+                    .clickable { onDismiss() },
+            contentAlignment = Alignment.Center,
+        ) {
+            Card(
+                modifier =
+                    Modifier
+                        .padding(32.dp)
+                        .clickable { /* prevent dismiss on card click */ },
+                shape = RoundedCornerShape(24.dp),
+                colors =
+                    CardDefaults.cardColors(
+                        containerColor = backgroundColor,
+                    ),
+                elevation = CardDefaults.cardElevation(defaultElevation = 8.dp),
+            ) {
+                Column(
+                    modifier =
+                        Modifier
+                            .padding(32.dp),
+                    horizontalAlignment = Alignment.CenterHorizontally,
+                    verticalArrangement = Arrangement.spacedBy(16.dp),
+                ) {
+                    // Trophy/emoji based on result
+                    val displayEmoji =
+                        when {
+                            isSpectator -> "GG"
+                            playerWon -> "GG"
+                            isDraw -> "="
+                            else -> "GG"
+                        }
+
+                    Box(
+                        modifier =
+                            Modifier
+                                .size(80.dp)
+                                .background(
+                                    when {
+                                        isSpectator -> MaterialTheme.colorScheme.primary.copy(alpha = 0.2f)
+                                        playerWon -> ComposeColor(0xFFFFD700).copy(alpha = 0.3f)
+                                        isDraw -> MaterialTheme.colorScheme.secondary.copy(alpha = 0.2f)
+                                        else -> MaterialTheme.colorScheme.error.copy(alpha = 0.2f)
+                                    },
+                                    CircleShape,
+                                ),
+                        contentAlignment = Alignment.Center,
+                    ) {
+                        Text(
+                            text = displayEmoji,
+                            fontSize = 28.sp,
+                            fontWeight = FontWeight.Bold,
+                            color =
+                                when {
+                                    isSpectator -> MaterialTheme.colorScheme.primary
+                                    playerWon -> ComposeColor(0xFFFFD700)
+                                    isDraw -> MaterialTheme.colorScheme.secondary
+                                    else -> MaterialTheme.colorScheme.error
+                                },
+                        )
+                    }
+
+                    Text(
+                        text = title,
+                        style = MaterialTheme.typography.headlineLarge,
+                        fontWeight = FontWeight.Bold,
+                        color =
+                            when {
+                                isSpectator -> MaterialTheme.colorScheme.onSurfaceVariant
+                                playerWon -> ComposeColor.White
+                                isDraw -> MaterialTheme.colorScheme.onSurfaceVariant
+                                else -> ComposeColor.White
+                            },
+                    )
+
+                    Text(
+                        text = subtitle,
+                        style = MaterialTheme.typography.bodyLarge,
+                        color =
+                            when {
+                                isSpectator -> MaterialTheme.colorScheme.onSurfaceVariant
+                                playerWon -> ComposeColor.White.copy(alpha = 0.9f)
+                                isDraw -> MaterialTheme.colorScheme.onSurfaceVariant
+                                else -> ComposeColor.White.copy(alpha = 0.9f)
+                            },
+                        textAlign = TextAlign.Center,
+                    )
+
+                    Spacer(modifier = Modifier.height(8.dp))
+
+                    Button(
+                        onClick = onDismiss,
+                    ) {
+                        Text("Continue")
+                    }
+                }
+            }
+        }
+    }
+}
+
+/**
+ * Compact game end info shown in controls area
+ */
+@Composable
+private fun GameEndInfo(
+    result: GameResult,
+    playerColor: Color,
+    isSpectator: Boolean,
+) {
+    val resultText =
+        when {
+            isSpectator -> {
+                when (result) {
+                    GameResult.WHITE_WINS -> "White wins"
+                    GameResult.BLACK_WINS -> "Black wins"
+                    GameResult.DRAW -> "Draw"
+                    GameResult.IN_PROGRESS -> "In progress"
+                }
+            }
+
+            result == GameResult.DRAW -> {
+                "Game drawn"
+            }
+
+            (result == GameResult.WHITE_WINS && playerColor == Color.WHITE) ||
+                (result == GameResult.BLACK_WINS && playerColor == Color.BLACK) -> {
+                "You won!"
+            }
+
+            else -> {
+                "You lost"
+            }
+        }
+
+    val backgroundColor =
+        when {
+            isSpectator -> {
+                MaterialTheme.colorScheme.surfaceVariant
+            }
+
+            result == GameResult.DRAW -> {
+                MaterialTheme.colorScheme.secondaryContainer
+            }
+
+            (result == GameResult.WHITE_WINS && playerColor == Color.WHITE) ||
+                (result == GameResult.BLACK_WINS && playerColor == Color.BLACK) -> {
+                ComposeColor(0xFF4CAF50).copy(alpha = 0.3f)
+            }
+
+            else -> {
+                MaterialTheme.colorScheme.errorContainer.copy(alpha = 0.5f)
+            }
+        }
+
+    Box(
+        modifier =
+            Modifier
+                .fillMaxWidth()
+                .background(backgroundColor, RoundedCornerShape(8.dp))
+                .padding(12.dp),
+        contentAlignment = Alignment.Center,
+    ) {
+        Text(
+            text = "Game Over - $resultText",
+            style = MaterialTheme.typography.bodyMedium,
+            fontWeight = FontWeight.Bold,
+            color = MaterialTheme.colorScheme.onSurface,
+        )
+    }
+}
+
+/**
+ * Helper data class for quadruple values
+ */
+private data class Quadruple<A, B, C, D>(
+    val first: A,
+    val second: B,
+    val third: C,
+    val fourth: D,
+)

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/MoveNavigator.kt

@@ -0,0 +1,137 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.KeyboardArrowLeft
+import androidx.compose.material.icons.filled.KeyboardArrowRight
+import androidx.compose.material.icons.filled.SkipNext
+import androidx.compose.material.icons.filled.SkipPrevious
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+
+/**
+ * Move navigation controls for stepping through chess game positions
+ * Shared composable for Android and Desktop platforms
+ *
+ * @param currentMove Current move index (0 = starting position)
+ * @param totalMoves Total number of moves in the game
+ * @param onMoveChange Callback when user navigates to a different move
+ * @param modifier Modifier for the navigator
+ */
+@Composable
+fun MoveNavigator(
+    currentMove: Int,
+    totalMoves: Int,
+    onMoveChange: (Int) -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    Row(
+        modifier = modifier.fillMaxWidth(),
+        horizontalArrangement = Arrangement.Center,
+        verticalAlignment = Alignment.CenterVertically,
+    ) {
+        // First move (starting position)
+        IconButton(
+            onClick = { onMoveChange(0) },
+            enabled = currentMove > 0,
+        ) {
+            Icon(
+                Icons.Default.SkipPrevious,
+                contentDescription = "Start position",
+                tint =
+                    if (currentMove > 0) {
+                        MaterialTheme.colorScheme.onSurface
+                    } else {
+                        MaterialTheme.colorScheme.onSurface.copy(alpha = 0.38f)
+                    },
+            )
+        }
+
+        // Previous move
+        IconButton(
+            onClick = { onMoveChange((currentMove - 1).coerceAtLeast(0)) },
+            enabled = currentMove > 0,
+        ) {
+            Icon(
+                Icons.Default.KeyboardArrowLeft,
+                contentDescription = "Previous move",
+                tint =
+                    if (currentMove > 0) {
+                        MaterialTheme.colorScheme.onSurface
+                    } else {
+                        MaterialTheme.colorScheme.onSurface.copy(alpha = 0.38f)
+                    },
+            )
+        }
+
+        // Current position indicator
+        Text(
+            text = "Move $currentMove / $totalMoves",
+            style = MaterialTheme.typography.bodyMedium,
+            modifier = Modifier.padding(horizontal = 16.dp),
+        )
+
+        // Next move
+        IconButton(
+            onClick = { onMoveChange((currentMove + 1).coerceAtMost(totalMoves)) },
+            enabled = currentMove < totalMoves,
+        ) {
+            Icon(
+                Icons.Default.KeyboardArrowRight,
+                contentDescription = "Next move",
+                tint =
+                    if (currentMove < totalMoves) {
+                        MaterialTheme.colorScheme.onSurface
+                    } else {
+                        MaterialTheme.colorScheme.onSurface.copy(alpha = 0.38f)
+                    },
+            )
+        }
+
+        // Last move (final position)
+        IconButton(
+            onClick = { onMoveChange(totalMoves) },
+            enabled = currentMove < totalMoves,
+        ) {
+            Icon(
+                Icons.Default.SkipNext,
+                contentDescription = "Final position",
+                tint =
+                    if (currentMove < totalMoves) {
+                        MaterialTheme.colorScheme.onSurface
+                    } else {
+                        MaterialTheme.colorScheme.onSurface.copy(alpha = 0.38f)
+                    },
+            )
+        }
+    }
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/PGNMetadata.kt

@@ -0,0 +1,135 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.unit.dp
+import com.vitorpamplona.quartz.nip64Chess.ChessGame
+
+/**
+ * Display PGN game metadata (Event, players, result, etc.)
+ * Shared composable for Android and Desktop platforms
+ *
+ * @param game The chess game with metadata to display
+ * @param modifier Modifier for the metadata display
+ */
+@Composable
+fun PGNMetadata(
+    game: ChessGame,
+    modifier: Modifier = Modifier,
+) {
+    Column(
+        modifier = modifier.fillMaxWidth(),
+        horizontalAlignment = Alignment.CenterHorizontally,
+        verticalArrangement = Arrangement.spacedBy(4.dp),
+    ) {
+        // Event name
+        game.event?.let { event ->
+            Text(
+                text = event,
+                style = MaterialTheme.typography.titleMedium,
+                fontWeight = FontWeight.Bold,
+                color = MaterialTheme.colorScheme.onSurface,
+            )
+        }
+
+        // Site/location (if available)
+        game.site?.let { site ->
+            Text(
+                text = site,
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+        }
+
+        // Players
+        if (game.white != null || game.black != null) {
+            Row(
+                horizontalArrangement = Arrangement.spacedBy(8.dp),
+                verticalAlignment = Alignment.CenterVertically,
+            ) {
+                game.white?.let { white ->
+                    Text(
+                        text = white,
+                        style = MaterialTheme.typography.bodyMedium,
+                        fontWeight = FontWeight.Medium,
+                        color = MaterialTheme.colorScheme.onSurface,
+                    )
+                }
+
+                Text(
+                    text = "vs",
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                )
+
+                game.black?.let { black ->
+                    Text(
+                        text = black,
+                        style = MaterialTheme.typography.bodyMedium,
+                        fontWeight = FontWeight.Medium,
+                        color = MaterialTheme.colorScheme.onSurface,
+                    )
+                }
+            }
+        }
+
+        // Date and Result
+        Row(
+            horizontalArrangement = Arrangement.spacedBy(12.dp),
+            verticalAlignment = Alignment.CenterVertically,
+        ) {
+            game.date?.let { date ->
+                Text(
+                    text = date,
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                )
+            }
+
+            // Result
+            Text(
+                text = "Result: ${game.result.notation}",
+                style = MaterialTheme.typography.bodySmall,
+                fontWeight = FontWeight.Medium,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+        }
+
+        // Round (if available)
+        game.round?.let { round ->
+            Text(
+                text = "Round $round",
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+        }
+    }
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/subscription/ChessFilterBuilder.kt

@@ -0,0 +1,310 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess.subscription
+
+import com.vitorpamplona.quartz.nip01Core.relay.client.pool.RelayBasedFilter
+import com.vitorpamplona.quartz.nip01Core.relay.filters.Filter
+import com.vitorpamplona.quartz.nip01Core.relay.normalizer.NormalizedRelayUrl
+import com.vitorpamplona.quartz.nip64Chess.JesterProtocol
+import com.vitorpamplona.quartz.utils.TimeUtils
+
+/**
+ * Shared filter builder for chess subscriptions using Jester protocol.
+ * Used by both Android and Desktop to ensure identical subscription behavior.
+ *
+ * Jester Protocol (kind 30):
+ * - All chess events use kind 30
+ * - Start events: e-tag references START_POSITION_HASH
+ * - Move events: e-tags [startEventId, headEventId]
+ * - Content JSON determines event type (kind: 0=start, 1=move, 2=chat)
+ *
+ * Builds 4 types of filters:
+ * 1. Personal filters - Events tagged with user's pubkey
+ * 2. Start/Challenge filters - Events referencing START_POSITION_HASH
+ * 3. Active game filters - Events referencing specific game startEventIds
+ * 4. Recent game filters - For spectating discovery
+ */
+object ChessFilterBuilder {
+    /** Jester protocol kind for all chess events */
+    private const val JESTER_KIND = JesterProtocol.KIND
+
+    /**
+     * Build all chess filters for a given subscription state.
+     * This is the main entry point - platforms call this to get filters.
+     *
+     * @param state The current subscription state with user info and active games
+     * @param sinceForRelay Function to get cached EOSE time for a relay (null if no cache)
+     * @return List of relay-specific filters to subscribe with
+     */
+    fun buildAllFilters(
+        state: ChessSubscriptionState,
+        sinceForRelay: (NormalizedRelayUrl) -> Long?,
+    ): List<RelayBasedFilter> {
+        val filters = mutableListOf<RelayBasedFilter>()
+        val now = TimeUtils.now()
+
+        // Filter 1: Personal events (challenges to us, moves in our games)
+        filters.addAll(
+            buildPersonalFilters(state.userPubkey, state.relays, sinceForRelay, now),
+        )
+
+        // Filter 2: All start/challenge events (for lobby display)
+        filters.addAll(
+            buildStartEventFilters(state.relays, sinceForRelay, now),
+        )
+
+        // Filter 3: Active game subscriptions (game-specific)
+        if (state.hasActiveGames) {
+            filters.addAll(
+                buildActiveGameFilters(
+                    state.allGameIds,
+                    state.userPubkey,
+                    state.opponentPubkeys,
+                    state.relays,
+                ),
+            )
+        }
+
+        // Filter 4: Recent game events (for spectating discovery)
+        filters.addAll(
+            buildRecentGameFilters(state.relays, sinceForRelay, now),
+        )
+
+        return filters
+    }
+
+    /**
+     * Personal events - tagged with user's pubkey.
+     * Catches: challenges directed at us, moves in our games.
+     */
+    fun buildPersonalFilters(
+        userPubkey: String,
+        relays: Set<NormalizedRelayUrl>,
+        sinceForRelay: (NormalizedRelayUrl) -> Long?,
+        now: Long = TimeUtils.now(),
+    ): List<RelayBasedFilter> {
+        val filter =
+            Filter(
+                kinds = listOf(JESTER_KIND),
+                tags = mapOf("p" to listOf(userPubkey)),
+                limit = 100,
+            )
+
+        return relays.map { relay ->
+            val sinceTime =
+                sinceForRelay(relay)
+                    ?: (now - ChessTimeWindows.CHALLENGE_WINDOW_SECONDS)
+            RelayBasedFilter(
+                relay = relay,
+                filter = filter.copy(since = sinceTime),
+            )
+        }
+    }
+
+    /**
+     * Start/challenge events (Jester pattern).
+     * In Jester protocol, start events reference the START_POSITION_HASH.
+     * This fetches all game starts for lobby display.
+     */
+    fun buildStartEventFilters(
+        relays: Set<NormalizedRelayUrl>,
+        sinceForRelay: (NormalizedRelayUrl) -> Long?,
+        now: Long = TimeUtils.now(),
+    ): List<RelayBasedFilter> {
+        val filter =
+            Filter(
+                kinds = listOf(JESTER_KIND),
+                tags = mapOf("e" to listOf(JesterProtocol.START_POSITION_HASH)),
+                limit = 100,
+            )
+
+        return relays.map { relay ->
+            val sinceTime =
+                sinceForRelay(relay)
+                    ?: (now - ChessTimeWindows.CHALLENGE_WINDOW_SECONDS)
+            RelayBasedFilter(
+                relay = relay,
+                filter = filter.copy(since = sinceTime),
+            )
+        }
+    }
+
+    /**
+     * Active game events - game-specific subscriptions.
+     * These filters ensure moves are received for games the user is playing.
+     *
+     * In Jester protocol:
+     * - Move events have e-tags: [startEventId, headEventId]
+     * - We filter by the first e-tag (startEventId) to get all moves for a game
+     * - We also filter by opponent authors and p-tag for redundancy
+     */
+    fun buildActiveGameFilters(
+        startEventIds: Set<String>,
+        userPubkey: String,
+        opponentPubkeys: Set<String>,
+        relays: Set<NormalizedRelayUrl>,
+    ): List<RelayBasedFilter> {
+        if (startEventIds.isEmpty()) return emptyList()
+
+        val filters = mutableListOf<RelayBasedFilter>()
+
+        // Game events: filter by e-tag (startEventId)
+        // This catches all moves/events for these games
+        val gameFilter =
+            Filter(
+                kinds = listOf(JESTER_KIND),
+                tags = mapOf("e" to startEventIds.toList()),
+                limit = 500,
+            )
+
+        relays.forEach { relay ->
+            filters.add(RelayBasedFilter(relay = relay, filter = gameFilter))
+        }
+
+        // Also filter by p-tag (opponent tagged us) for redundancy
+        val tagFilter =
+            Filter(
+                kinds = listOf(JESTER_KIND),
+                tags = mapOf("p" to listOf(userPubkey)),
+                limit = 200,
+            )
+
+        relays.forEach { relay ->
+            filters.add(RelayBasedFilter(relay = relay, filter = tagFilter))
+        }
+
+        // Also filter by authors (opponent pubkeys) for redundancy
+        if (opponentPubkeys.isNotEmpty()) {
+            val authorFilter =
+                Filter(
+                    kinds = listOf(JESTER_KIND),
+                    authors = opponentPubkeys.toList(),
+                    limit = 200,
+                )
+
+            relays.forEach { relay ->
+                filters.add(RelayBasedFilter(relay = relay, filter = authorFilter))
+            }
+        }
+
+        return filters
+    }
+
+    /**
+     * Recent game events for spectating discovery.
+     * Uses longer time window (7 days) to catch ongoing games.
+     */
+    fun buildRecentGameFilters(
+        relays: Set<NormalizedRelayUrl>,
+        sinceForRelay: (NormalizedRelayUrl) -> Long?,
+        now: Long = TimeUtils.now(),
+    ): List<RelayBasedFilter> {
+        val filter =
+            Filter(
+                kinds = listOf(JESTER_KIND),
+                limit = 100,
+            )
+
+        return relays.map { relay ->
+            val sinceTime =
+                sinceForRelay(relay)
+                    ?: (now - ChessTimeWindows.GAME_EVENT_WINDOW_SECONDS)
+            RelayBasedFilter(
+                relay = relay,
+                filter = filter.copy(since = sinceTime),
+            )
+        }
+    }
+
+    // ===================================================
+    // Simple filters for one-shot fetches (ChessRelayFetcher)
+    // ===================================================
+
+    /**
+     * Filter for all events related to a specific game.
+     * Used for one-shot fetch when loading a game.
+     *
+     * In Jester protocol, all game events reference the startEventId via e-tag.
+     */
+    fun gameEventsFilter(startEventId: String): Filter =
+        Filter(
+            kinds = listOf(JESTER_KIND),
+            tags = mapOf("e" to listOf(startEventId)),
+            limit = 500,
+        )
+
+    /**
+     * Filter for start/challenge events in the last 24 hours.
+     * Used for one-shot fetch to populate lobby.
+     *
+     * Start events reference the START_POSITION_HASH.
+     */
+    fun challengesFilter(userPubkey: String? = null): Filter {
+        val now = TimeUtils.now()
+        return Filter(
+            kinds = listOf(JESTER_KIND),
+            tags = mapOf("e" to listOf(JesterProtocol.START_POSITION_HASH)),
+            since = now - ChessTimeWindows.CHALLENGE_WINDOW_SECONDS,
+            limit = 100,
+        )
+    }
+
+    /**
+     * Filter for recent game activity for spectating discovery.
+     * Fetches events from the last 7 days.
+     */
+    fun recentGamesFilter(): Filter {
+        val now = TimeUtils.now()
+        return Filter(
+            kinds = listOf(JESTER_KIND),
+            since = now - ChessTimeWindows.GAME_EVENT_WINDOW_SECONDS,
+            limit = 200,
+        )
+    }
+
+    /**
+     * Filter for user's own chess events (events they authored).
+     * Used to discover games the user is participating in.
+     */
+    fun userGamesFilter(userPubkey: String): Filter {
+        val now = TimeUtils.now()
+        return Filter(
+            kinds = listOf(JESTER_KIND),
+            authors = listOf(userPubkey),
+            since = now - ChessTimeWindows.GAME_EVENT_WINDOW_SECONDS,
+            limit = 200,
+        )
+    }
+
+    /**
+     * Filter for events tagged with user's pubkey (games they're participating in).
+     * Complements userGamesFilter to find games where user is the opponent.
+     */
+    fun userTaggedFilter(userPubkey: String): Filter {
+        val now = TimeUtils.now()
+        return Filter(
+            kinds = listOf(JESTER_KIND),
+            tags = mapOf("p" to listOf(userPubkey)),
+            since = now - ChessTimeWindows.GAME_EVENT_WINDOW_SECONDS,
+            limit = 200,
+        )
+    }
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/subscription/ChessSubscriptionController.kt

@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess.subscription
+
+import kotlinx.coroutines.flow.StateFlow
+
+/**
+ * Interface for platform-specific chess subscription management.
+ *
+ * Implementations handle the actual relay subscription mechanics while
+ * using [ChessFilterBuilder] for consistent filter construction.
+ *
+ * Key responsibilities:
+ * - Subscribe/unsubscribe to chess events on relays
+ * - Update filters when active games change
+ * - Track EOSE (End of Stored Events) per relay for efficient re-subscription
+ */
+interface ChessSubscriptionController {
+    /** Current subscription state, null if not subscribed */
+    val currentState: StateFlow<ChessSubscriptionState?>
+
+    /**
+     * Subscribe to chess events with the given state.
+     * Replaces any existing subscription.
+     */
+    fun subscribe(state: ChessSubscriptionState)
+
+    /** Unsubscribe from all chess events */
+    fun unsubscribe()
+
+    /**
+     * Update active game IDs and refresh subscription filters.
+     * This is the key method for dynamic subscription updates.
+     *
+     * When a game starts or ends, call this to update the filters
+     * so moves are properly received for active games.
+     *
+     * @param activeGameIds Game IDs the user is actively playing
+     * @param spectatingGameIds Game IDs the user is watching (optional)
+     */
+    fun updateActiveGames(
+        activeGameIds: Set<String>,
+        spectatingGameIds: Set<String> = emptySet(),
+    )
+
+    /**
+     * Force refresh all filters from relays.
+     * Clears EOSE cache so full history is re-fetched.
+     */
+    fun forceRefresh()
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/subscription/ChessSubscriptionState.kt

@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess.subscription
+
+import androidx.compose.runtime.Immutable
+import com.vitorpamplona.quartz.nip01Core.relay.normalizer.NormalizedRelayUrl
+
+/**
+ * Immutable state for chess relay subscriptions.
+ * Used to generate subscription filters and track subscription identity.
+ *
+ * When any of these values change, a new subscription should be created
+ * with updated filters.
+ */
+@Immutable
+data class ChessSubscriptionState(
+    /** User's public key (hex) for filtering personal events */
+    val userPubkey: String,
+    /** Set of relays to subscribe to */
+    val relays: Set<NormalizedRelayUrl>,
+    /** Game IDs the user is actively playing */
+    val activeGameIds: Set<String> = emptySet(),
+    /** Game IDs the user is spectating */
+    val spectatingGameIds: Set<String> = emptySet(),
+    /** Opponent pubkeys for active games (to filter their moves) */
+    val opponentPubkeys: Set<String> = emptySet(),
+) {
+    /**
+     * Unique subscription ID that changes when game IDs change.
+     * Used for:
+     * - Subscription deduplication
+     * - EOSE cache keying
+     * - Detecting when filters need to be refreshed
+     */
+    fun subscriptionId(): String =
+        buildString {
+            append("chess-")
+            append(userPubkey.take(8))
+            if (allGameIds.isNotEmpty()) {
+                append("-g")
+                append(allGameIds.sorted().hashCode())
+            }
+        }
+
+    /** All game IDs requiring move subscriptions (active + spectating) */
+    val allGameIds: Set<String>
+        get() = activeGameIds + spectatingGameIds
+
+    /** True if user has any active or spectating games */
+    val hasActiveGames: Boolean
+        get() = allGameIds.isNotEmpty()
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/chess/subscription/ChessTimeWindows.kt

@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess.subscription
+
+/**
+ * Shared time window constants for chess subscriptions.
+ * Used by both Android and Desktop to ensure consistent behavior.
+ */
+object ChessTimeWindows {
+    /**
+     * 24 hours - challenges older than this are considered expired.
+     * Used for challenge and accept event filters.
+     */
+    const val CHALLENGE_WINDOW_SECONDS = 24 * 60 * 60L
+
+    /**
+     * 7 days - default lookback for game events when no EOSE cache exists.
+     * This prevents loading ancient game history on first connection
+     * while still allowing recovery of recent games.
+     */
+    const val GAME_EVENT_WINDOW_SECONDS = 7 * 24 * 60 * 60L
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/data/UserMetadataCache.kt

@@ -0,0 +1,144 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.data
+
+import com.vitorpamplona.quartz.nip01Core.metadata.UserMetadata
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
+
+/**
+ * Simple data class for cached user display info
+ */
+data class UserDisplayInfo(
+    val pubkey: String,
+    val displayName: String?,
+    val pictureUrl: String?,
+    val nip05: String?,
+)
+
+/**
+ * Lightweight user metadata cache for UI display.
+ * Can be used by any feature (chess, chat, etc.) that needs user info.
+ *
+ * Thread-safe via StateFlow updates.
+ */
+class UserMetadataCache {
+    private val _metadata = MutableStateFlow<Map<String, UserMetadata>>(emptyMap())
+    val metadata: StateFlow<Map<String, UserMetadata>> = _metadata.asStateFlow()
+
+    private val _pubkeysNeeded = MutableStateFlow<Set<String>>(emptySet())
+    val pubkeysNeeded: StateFlow<Set<String>> = _pubkeysNeeded.asStateFlow()
+
+    /**
+     * Add or update metadata for a pubkey
+     */
+    fun put(
+        pubkey: String,
+        userMetadata: UserMetadata,
+    ) {
+        _metadata.value = _metadata.value + (pubkey to userMetadata)
+        _pubkeysNeeded.value = _pubkeysNeeded.value - pubkey
+    }
+
+    /**
+     * Get metadata for a pubkey (may be null if not cached)
+     */
+    fun get(pubkey: String): UserMetadata? = _metadata.value[pubkey]
+
+    /**
+     * Check if metadata is cached for a pubkey
+     */
+    fun contains(pubkey: String): Boolean = _metadata.value.containsKey(pubkey)
+
+    /**
+     * Request metadata for a pubkey (adds to needed set if not cached)
+     */
+    fun request(pubkey: String) {
+        if (!contains(pubkey) && pubkey !in _pubkeysNeeded.value) {
+            _pubkeysNeeded.value = _pubkeysNeeded.value + pubkey
+        }
+    }
+
+    /**
+     * Request metadata for multiple pubkeys
+     */
+    fun requestAll(pubkeys: Collection<String>) {
+        val newNeeded = pubkeys.filter { !contains(it) && it !in _pubkeysNeeded.value }
+        if (newNeeded.isNotEmpty()) {
+            _pubkeysNeeded.value = _pubkeysNeeded.value + newNeeded
+        }
+    }
+
+    /**
+     * Get display name for a pubkey, falling back to truncated pubkey
+     */
+    fun getDisplayName(pubkey: String): String {
+        val meta = get(pubkey)
+        return meta?.bestName() ?: formatPubkeyShort(pubkey)
+    }
+
+    /**
+     * Get profile picture URL for a pubkey
+     */
+    fun getPictureUrl(pubkey: String): String? = get(pubkey)?.profilePicture()
+
+    /**
+     * Get display info for a pubkey (for UI binding)
+     */
+    fun getDisplayInfo(pubkey: String): UserDisplayInfo {
+        val meta = get(pubkey)
+        return UserDisplayInfo(
+            pubkey = pubkey,
+            displayName = meta?.bestName(),
+            pictureUrl = meta?.profilePicture(),
+            nip05 = meta?.nip05,
+        )
+    }
+
+    /**
+     * Clear metadata that was requested but hasn't been fetched
+     * (call when pubkeys are no longer needed)
+     */
+    fun clearNeeded(pubkeys: Collection<String>) {
+        _pubkeysNeeded.value = _pubkeysNeeded.value - pubkeys.toSet()
+    }
+
+    /**
+     * Clear all cached metadata
+     */
+    fun clear() {
+        _metadata.value = emptyMap()
+        _pubkeysNeeded.value = emptySet()
+    }
+
+    companion object {
+        /**
+         * Format pubkey for display (npub-style truncation)
+         */
+        fun formatPubkeyShort(pubkey: String): String =
+            if (pubkey.length > 12) {
+                "${pubkey.take(8)}...${pubkey.takeLast(4)}"
+            } else {
+                pubkey
+            }
+    }
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/model/Note.kt

@@ -22,6 +22,7 @@ package com.vitorpamplona.amethyst.commons.model
 
 import androidx.compose.runtime.Immutable
 import androidx.compose.runtime.Stable
+import com.vitorpamplona.amethyst.commons.model.nip88Polls.PollResponsesCache
 import com.vitorpamplona.amethyst.commons.threading.checkNotInMainThread
 import com.vitorpamplona.amethyst.commons.util.firstFullCharOrEmoji
 import com.vitorpamplona.amethyst.commons.util.replace
@@ -131,6 +132,12 @@ open class Note(
         removeReport(note)
     }
 
+    var poll: PollResponsesCache? = null
+
+    fun pollStateOrNull(): PollResponsesCache? = poll
+
+    fun pollState(): PollResponsesCache = poll ?: PollResponsesCache().also { poll = it }
+
     // These fields are updated every time an event related to this note is received.
     var replies = listOf<Note>()
         private set
@@ -1007,6 +1014,34 @@ public inline fun <T> Iterable<Note>.anyEvent(predicate: (T) -> Boolean): Boolea
     return false
 }
 
+public inline fun <T> Iterable<Note>.filterEvents(predicate: (T) -> Boolean): List<T> {
+    if (this is Collection && isEmpty()) return emptyList()
+
+    val dest = ArrayList<T>()
+    for (note in this) {
+        val noteEvent = note.event as? T
+        if (noteEvent != null && predicate(noteEvent)) {
+            dest.add(noteEvent)
+        }
+    }
+    return dest
+}
+
+public inline fun <T> Iterable<Note>.filterAuthoredEvents(pubkey: HexKey): List<T> {
+    if (this is Collection && isEmpty()) return emptyList()
+
+    val dest = ArrayList<T>()
+    for (note in this) {
+        if (note.author?.pubkeyHex != pubkey) {
+            val noteEvent = note.event as? T
+            if (noteEvent != null) {
+                dest.add(noteEvent)
+            }
+        }
+    }
+    return dest
+}
+
 public inline fun Iterable<Note>.anyNotNullEvent(predicate: (Event) -> Boolean): Boolean {
     if (this is Collection && isEmpty()) return false
     for (note in this) {
@@ -1015,3 +1050,21 @@ public inline fun Iterable<Note>.anyNotNullEvent(predicate: (Event) -> Boolean):
     }
     return false
 }
+
+fun <T : Event> List<Note>.latestByAuthor(): Map<User, T> {
+    val oneResponsePerUser = mutableMapOf<User, T>()
+
+    forEach { note ->
+        val author = note.author ?: return@forEach
+        val event = note.event as? T ?: return@forEach
+
+        val currentResponse = oneResponsePerUser[author]
+        if (currentResponse == null) {
+            oneResponsePerUser[author] = event
+        } else if (event.createdAt > currentResponse.createdAt) {
+            oneResponsePerUser[author] = event
+        }
+    }
+
+    return oneResponsePerUser
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/model/nip18Reposts/RepostAction.kt

@@ -22,7 +22,7 @@ package com.vitorpamplona.amethyst.commons.model.nip18Reposts
 
 import com.vitorpamplona.amethyst.commons.model.Note
 import com.vitorpamplona.quartz.nip01Core.core.Event
-import com.vitorpamplona.quartz.nip01Core.relay.normalizer.RelayUrlNormalizer
+import com.vitorpamplona.quartz.nip01Core.hints.EventHintBundle
 import com.vitorpamplona.quartz.nip01Core.signers.NostrSigner
 import com.vitorpamplona.quartz.nip18Reposts.GenericRepostEvent
 import com.vitorpamplona.quartz.nip18Reposts.RepostEvent
@@ -35,34 +35,26 @@ object RepostAction {
     /**
      * Creates a signed repost event.
      *
-     * @param event The event to repost
+     * @param eventHint The event to repost
      * @param signer The NostrSigner to sign the event
-     * @param noteHint Optional relay hint where the note was seen
-     * @param authorHint Optional relay hint for the author's outbox
      * @return Signed repost event ready to broadcast
      * @throws IllegalStateException if signer is not writeable
      */
     suspend fun repost(
-        event: Event,
+        eventHint: EventHintBundle<Event>,
         signer: NostrSigner,
-        noteHint: String? = null,
-        authorHint: String? = null,
     ): Event {
         if (!signer.isWriteable()) {
             throw IllegalStateException("Cannot repost: signer is not writeable")
         }
 
-        // Normalize relay hints
-        val normalizedNoteHint = noteHint?.let { RelayUrlNormalizer.normalizeOrNull(it) }
-        val normalizedAuthorHint = authorHint?.let { RelayUrlNormalizer.normalizeOrNull(it) }
-
         // Use NIP-18 RepostEvent (kind 6) for text notes (kind 1)
         // Use GenericRepostEvent (kind 16) for all other kinds
         val template =
-            if (event.kind == 1) {
-                RepostEvent.build(event, normalizedNoteHint, normalizedAuthorHint)
+            if (eventHint.event.kind == 1) {
+                RepostEvent.build(eventHint)
             } else {
-                GenericRepostEvent.build(event, normalizedNoteHint, normalizedAuthorHint)
+                GenericRepostEvent.build(eventHint)
             }
 
         return signer.sign(template)
@@ -86,10 +78,8 @@ object RepostAction {
         if (!signer.isWriteable()) return null
         if (note.hasBoostedInTheLast5Minutes(signer.pubKey)) return null
 
-        val noteEvent = note.event ?: return null
-        val noteHint = note.relayHintUrl()?.url
-        val authorHint = note.author?.bestRelayHint()?.url
+        val hint = note.toEventHint<Event>() ?: return null
 
-        return repost(noteEvent, signer, noteHint, authorHint)
+        return repost(hint, signer)
     }
 }

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/model/nip25Reactions/ReactionAction.kt

@@ -24,7 +24,6 @@ import com.vitorpamplona.amethyst.commons.model.Note
 import com.vitorpamplona.amethyst.commons.model.User
 import com.vitorpamplona.quartz.nip01Core.core.Event
 import com.vitorpamplona.quartz.nip01Core.hints.EventHintBundle
-import com.vitorpamplona.quartz.nip01Core.relay.normalizer.RelayUrlNormalizer
 import com.vitorpamplona.quartz.nip01Core.signers.NostrSigner
 import com.vitorpamplona.quartz.nip17Dm.NIP17Factory
 import com.vitorpamplona.quartz.nip17Dm.base.NIP17Group
@@ -49,18 +48,14 @@ object ReactionAction {
      * @throws IllegalStateException if signer is not writeable
      */
     suspend fun reactTo(
-        event: Event,
+        eventHint: EventHintBundle<Event>,
         reaction: String,
         signer: NostrSigner,
-        relayHint: String? = null,
     ): ReactionEvent {
         if (!signer.isWriteable()) {
             throw IllegalStateException("Cannot react: signer is not writeable")
         }
 
-        val normalizedRelayHint = relayHint?.let { RelayUrlNormalizer.normalizeOrNull(it) }
-        val eventHint = EventHintBundle(event, normalizedRelayHint)
-
         // Handle custom emoji reactions (format: ":emoji_name:")
         val template =
             if (reaction.startsWith(":")) {
@@ -82,10 +77,9 @@ object ReactionAction {
      * Creates a "like" reaction ("+").
      */
     suspend fun like(
-        event: Event,
+        event: EventHintBundle<Event>,
         signer: NostrSigner,
-        relayHint: String? = null,
-    ): ReactionEvent = reactTo(event, "+", signer, relayHint)
+    ): ReactionEvent = reactTo(event, "+", signer)
 
     /**
      * Advanced: React to an event with support for NIP-17 private groups.
@@ -102,7 +96,6 @@ object ReactionAction {
      * @param onPrivate Callback for private group reactions (returns NIP17Factory.Result)
      */
     suspend fun reactToWithGroupSupport(
-        event: Event,
         eventHint: EventHintBundle<Event>,
         reaction: String,
         signer: NostrSigner,
@@ -113,6 +106,8 @@ object ReactionAction {
             throw IllegalStateException("Cannot react: signer is not writeable")
         }
 
+        val event = eventHint.event
+
         // Check if this is a NIP-17 private group event
         if (event is NIP17Group) {
             val users = event.groupMembers().toList()
@@ -185,9 +180,8 @@ object ReactionAction {
         if (!signer.isWriteable()) return
         if (note.hasReacted(by, reaction)) return
 
-        val noteEvent = note.event ?: return
         val eventHint = note.toEventHint<Event>() ?: return
 
-        reactToWithGroupSupport(noteEvent, eventHint, reaction, signer, onPublic, onPrivate)
+        reactToWithGroupSupport(eventHint, reaction, signer, onPublic, onPrivate)
     }
 }

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/model/nip88Polls/PollResponsesCache.kt

@@ -0,0 +1,146 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.model.nip88Polls
+
+import androidx.compose.runtime.Stable
+import com.vitorpamplona.amethyst.commons.model.Note
+import com.vitorpamplona.amethyst.commons.model.User
+import com.vitorpamplona.amethyst.commons.model.UserDependencies
+import com.vitorpamplona.amethyst.commons.model.latestByAuthor
+import com.vitorpamplona.quartz.nip01Core.core.HexKey
+import com.vitorpamplona.quartz.nip88Polls.response.PollResponseEvent
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.combine
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.update
+import kotlin.collections.component1
+import kotlin.collections.component2
+import kotlin.collections.set
+
+@Stable
+class PollResponsesCache : UserDependencies {
+    companion object {
+        val DefaultFeedOrder: Comparator<PollResponseEvent> =
+            compareByDescending<PollResponseEvent> { it.createdAt }.thenBy { it.id }
+    }
+
+    class ResponseTally(
+        val allResponses: List<Note> = emptyList(),
+    ) {
+        val votes: Map<User, PollResponseEvent> = allResponses.latestByAuthor()
+        val tally: Map<String, Set<User>> = votes.votesByOption()
+
+        fun winning() = tally.maxByOrNull { it.value.size }?.key
+
+        fun totalVotes() = tally.entries.sumOf { it.value.size }
+    }
+
+    val responses = MutableStateFlow(ResponseTally())
+
+    fun addResponse(note: Note) {
+        // if it's already there, quick exit
+        if (responses.value.allResponses.contains(note)) return
+
+        responses.update {
+            ResponseTally(
+                it.allResponses + note,
+            )
+        }
+    }
+
+    fun removeResponse(deleteNote: Note) {
+        // if it's not already there, quick exit
+        if (!responses.value.allResponses.contains(deleteNote)) return
+
+        responses.update {
+            ResponseTally(
+                it.allResponses - deleteNote,
+            )
+        }
+    }
+
+    fun ResponseTally.filterTo(
+        code: String,
+        forKey: HexKey,
+        priority: Set<HexKey>,
+    ): TallyResults {
+        val comparator = compareByDescending<User> { it.pubkeyHex == forKey }.thenByDescending { it.pubkeyHex in priority }.thenBy { it.pubkeyHex }
+
+        val usersThatVotedForThisOption = tally[code] ?: emptyList()
+
+        val votes = totalVotes()
+
+        val percent =
+            if (votes > 0) {
+                usersThatVotedForThisOption.size.toFloat() / votes.toFloat()
+            } else {
+                0f
+            }
+
+        val sortedUsers = usersThatVotedForThisOption.sortedWith(comparator)
+
+        return TallyResults(sortedUsers, percent, code == winning())
+    }
+
+    fun currentTally(
+        code: String,
+        forKey: HexKey,
+        priorityAccounts: Set<HexKey>,
+    ): TallyResults = responses.value.filterTo(code, forKey, priorityAccounts)
+
+    fun tallyFlow(
+        code: String,
+        forKey: HexKey,
+        priorityAccounts: Flow<Set<HexKey>>,
+    ): Flow<TallyResults> =
+        combine(responses, priorityAccounts) { responses, priority ->
+            responses.filterTo(code, forKey, priority)
+        }
+
+    fun hasPubKeyVoted(user: User): Boolean = responses.value.votes.containsKey(user)
+
+    fun hasPubKeyVotedFlow(user: User): Flow<Boolean> = responses.map { hasPubKeyVoted(user) }.distinctUntilChanged()
+}
+
+@Stable
+class TallyResults(
+    val users: List<User> = emptyList(),
+    val percent: Float = 0.0f,
+    val isWinning: Boolean = false,
+)
+
+fun Map<User, PollResponseEvent>.votesByOption(): Map<String, Set<User>> {
+    val tally = mutableMapOf<String, MutableSet<User>>()
+
+    this.forEach { (user, responseEvent) ->
+        responseEvent.responses().forEach { code ->
+            val currentTally = tally[code]
+            if (currentTally == null) {
+                tally[code] = mutableSetOf(user)
+            } else {
+                currentTally.add(user)
+            }
+        }
+    }
+    return tally
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/profile/ProfileBroadcastBanner.kt

@@ -0,0 +1,192 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.profile
+
+import androidx.compose.animation.AnimatedVisibility
+import androidx.compose.animation.animateContentSize
+import androidx.compose.animation.core.animateFloatAsState
+import androidx.compose.animation.core.tween
+import androidx.compose.animation.fadeIn
+import androidx.compose.animation.fadeOut
+import androidx.compose.animation.slideInVertically
+import androidx.compose.animation.slideOutVertically
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.CheckCircle
+import androidx.compose.material.icons.filled.Error
+import androidx.compose.material.icons.filled.Sync
+import androidx.compose.material3.Icon
+import androidx.compose.material3.LinearProgressIndicator
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.unit.dp
+
+/**
+ * Shared banner showing profile metadata broadcast progress.
+ * Works on both Android and Desktop via Compose Multiplatform.
+ */
+@Composable
+fun ProfileBroadcastBanner(
+    status: ProfileBroadcastStatus,
+    onTap: () -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    val isVisible = status !is ProfileBroadcastStatus.Idle
+
+    AnimatedVisibility(
+        visible = isVisible,
+        enter = slideInVertically(initialOffsetY = { -it }) + fadeIn(tween(200)),
+        exit = slideOutVertically(targetOffsetY = { -it }) + fadeOut(tween(150)),
+        modifier = modifier,
+    ) {
+        Surface(
+            color = getStatusBackgroundColor(status),
+            tonalElevation = 2.dp,
+            modifier =
+                Modifier
+                    .fillMaxWidth()
+                    .clickable(onClick = onTap),
+        ) {
+            Row(
+                verticalAlignment = Alignment.CenterVertically,
+                horizontalArrangement = Arrangement.spacedBy(8.dp),
+                modifier =
+                    Modifier
+                        .padding(horizontal = 16.dp, vertical = 10.dp)
+                        .animateContentSize(),
+            ) {
+                Icon(
+                    imageVector = getStatusIcon(status),
+                    contentDescription = null,
+                    tint = getStatusIconColor(status),
+                    modifier = Modifier.size(18.dp),
+                )
+
+                Column(modifier = Modifier.weight(1f)) {
+                    Row(
+                        horizontalArrangement = Arrangement.SpaceBetween,
+                        verticalAlignment = Alignment.CenterVertically,
+                        modifier = Modifier.fillMaxWidth(),
+                    ) {
+                        Text(
+                            text = getStatusText(status),
+                            style = MaterialTheme.typography.bodySmall,
+                            color = MaterialTheme.colorScheme.onSurface,
+                            maxLines = 1,
+                            overflow = TextOverflow.Ellipsis,
+                            modifier = Modifier.weight(1f),
+                        )
+
+                        Spacer(Modifier.width(8.dp))
+
+                        Text(
+                            text = getStatusDetail(status),
+                            style = MaterialTheme.typography.labelMedium,
+                            color = getStatusDetailColor(status),
+                        )
+                    }
+
+                    // Progress bar for broadcasting
+                    if (status is ProfileBroadcastStatus.Broadcasting) {
+                        Spacer(Modifier.height(4.dp))
+
+                        val animatedProgress by animateFloatAsState(
+                            targetValue = status.progress,
+                            animationSpec = tween(300),
+                            label = "broadcastProgress",
+                        )
+
+                        LinearProgressIndicator(
+                            progress = { animatedProgress },
+                            modifier = Modifier.fillMaxWidth(),
+                            color = MaterialTheme.colorScheme.primary,
+                            trackColor = MaterialTheme.colorScheme.surfaceVariant,
+                        )
+                    }
+                }
+            }
+        }
+    }
+}
+
+@Composable
+private fun getStatusBackgroundColor(status: ProfileBroadcastStatus): Color =
+    when (status) {
+        is ProfileBroadcastStatus.Failed -> MaterialTheme.colorScheme.errorContainer.copy(alpha = 0.9f)
+        is ProfileBroadcastStatus.Success -> MaterialTheme.colorScheme.primaryContainer.copy(alpha = 0.9f)
+        else -> MaterialTheme.colorScheme.surfaceContainer
+    }
+
+private fun getStatusIcon(status: ProfileBroadcastStatus): ImageVector =
+    when (status) {
+        is ProfileBroadcastStatus.Broadcasting -> Icons.Default.Sync
+        is ProfileBroadcastStatus.Success -> Icons.Default.CheckCircle
+        is ProfileBroadcastStatus.Failed -> Icons.Default.Error
+        is ProfileBroadcastStatus.Idle -> Icons.Default.CheckCircle
+    }
+
+@Composable
+private fun getStatusIconColor(status: ProfileBroadcastStatus): Color =
+    when (status) {
+        is ProfileBroadcastStatus.Failed -> MaterialTheme.colorScheme.error
+        is ProfileBroadcastStatus.Success -> MaterialTheme.colorScheme.primary
+        else -> MaterialTheme.colorScheme.primary
+    }
+
+private fun getStatusText(status: ProfileBroadcastStatus): String =
+    when (status) {
+        is ProfileBroadcastStatus.Broadcasting -> "Updating ${status.fieldName}..."
+        is ProfileBroadcastStatus.Success -> "Updated ${status.fieldName}"
+        is ProfileBroadcastStatus.Failed -> "Failed to update ${status.fieldName}"
+        is ProfileBroadcastStatus.Idle -> ""
+    }
+
+private fun getStatusDetail(status: ProfileBroadcastStatus): String =
+    when (status) {
+        is ProfileBroadcastStatus.Broadcasting -> "[${status.successCount}/${status.totalRelays}]"
+        is ProfileBroadcastStatus.Success -> "${status.relayCount} relays"
+        is ProfileBroadcastStatus.Failed -> "Tap to retry"
+        is ProfileBroadcastStatus.Idle -> ""
+    }
+
+@Composable
+private fun getStatusDetailColor(status: ProfileBroadcastStatus): Color =
+    when (status) {
+        is ProfileBroadcastStatus.Failed -> MaterialTheme.colorScheme.error
+        else -> MaterialTheme.colorScheme.primary
+    }

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/profile/ProfileBroadcastStatus.kt

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.profile
+
+/**
+ * Status of profile metadata broadcast to relays.
+ */
+sealed class ProfileBroadcastStatus {
+    data object Idle : ProfileBroadcastStatus()
+
+    data class Broadcasting(
+        val fieldName: String,
+        val successCount: Int,
+        val totalRelays: Int,
+    ) : ProfileBroadcastStatus() {
+        val progress: Float get() = if (totalRelays > 0) successCount.toFloat() / totalRelays else 0f
+    }
+
+    data class Success(
+        val fieldName: String,
+        val relayCount: Int,
+    ) : ProfileBroadcastStatus()
+
+    data class Failed(
+        val fieldName: String,
+        val error: String,
+    ) : ProfileBroadcastStatus()
+}

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/ui/feeds/FeedState.kt

@@ -28,14 +28,18 @@ import kotlinx.coroutines.flow.MutableStateFlow
 
 @Stable
 sealed class FeedState {
+    @Stable
     object Loading : FeedState()
 
+    @Stable
     class Loaded(
         val feed: MutableStateFlow<LoadedFeedState<Note>>,
     ) : FeedState()
 
+    @Stable
     object Empty : FeedState()
 
+    @Stable
     class FeedError(
         val errorMessage: String,
     ) : FeedState()

commons/src/jvmAndroid/kotlin/com/vitorpamplona/amethyst/commons/chess/ChessEventBroadcaster.kt

@@ -0,0 +1,152 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.chess
+
+import com.vitorpamplona.quartz.nip01Core.core.Event
+import com.vitorpamplona.quartz.nip01Core.relay.client.INostrClient
+import com.vitorpamplona.quartz.nip01Core.relay.client.accessories.sendAndWaitForResponse
+import com.vitorpamplona.quartz.nip01Core.relay.client.reqs.IRequestListener
+import com.vitorpamplona.quartz.nip01Core.relay.client.single.newSubId
+import com.vitorpamplona.quartz.nip01Core.relay.filters.Filter
+import com.vitorpamplona.quartz.nip01Core.relay.normalizer.NormalizedRelayUrl
+import com.vitorpamplona.quartz.nip64Chess.JesterProtocol
+import kotlinx.coroutines.delay
+
+/**
+ * Result of broadcasting an event
+ */
+data class BroadcastResult(
+    val success: Boolean,
+    val relayResults: Map<NormalizedRelayUrl, Boolean>,
+    val message: String,
+)
+
+/**
+ * Helper for broadcasting chess events to relays with reliable delivery.
+ *
+ * Uses sendAndWaitForResponse to get actual OK confirmations from relays,
+ * ensuring the event was actually received and accepted.
+ */
+class ChessEventBroadcaster(
+    private val client: INostrClient,
+) {
+    /**
+     * Broadcast an event to the chess relays with confirmation.
+     *
+     * This method:
+     * 1. Triggers relay connections via a dummy subscription
+     * 2. Waits for relays to connect
+     * 3. Sends the event and waits for OK responses
+     *
+     * @param event The signed event to broadcast
+     * @param timeoutSeconds Maximum time to wait for relay responses
+     * @return BroadcastResult with success status
+     */
+    suspend fun broadcast(
+        event: Event,
+        timeoutSeconds: Long = 15L,
+    ): BroadcastResult {
+        val targetRelays = ChessConfig.CHESS_RELAYS.map { NormalizedRelayUrl(it) }.toSet()
+        val subId = newSubId()
+
+        // Step 1: Check which relays are already connected
+        val initialConnected = client.connectedRelaysFlow().value
+        val alreadyConnected = targetRelays.intersect(initialConnected)
+        val needsConnection = targetRelays - alreadyConnected
+
+        // Step 2: If some relays need connection, open a subscription to trigger it
+        if (needsConnection.isNotEmpty()) {
+            // Use a valid filter with recent since timestamp to trigger connection
+            // without expecting real results
+            val dummyFilter =
+                Filter(
+                    kinds = listOf(JesterProtocol.KIND),
+                    since = (System.currentTimeMillis() / 1000) + 3600, // 1 hour in future = no results
+                    limit = 1,
+                )
+
+            val listener =
+                object : IRequestListener {
+                    override fun onEvent(
+                        event: Event,
+                        isLive: Boolean,
+                        relay: NormalizedRelayUrl,
+                        forFilters: List<Filter>?,
+                    ) { }
+
+                    override fun onEose(
+                        relay: NormalizedRelayUrl,
+                        forFilters: List<Filter>?,
+                    ) { }
+                }
+
+            // Open subscription to all target relays (triggers connection)
+            val filterMap = targetRelays.associateWith { listOf(dummyFilter) }
+            client.openReqSubscription(subId, filterMap, listener)
+
+            // Wait for relays to connect (poll with timeout)
+            waitForRelays(targetRelays, 5000L)
+
+            // Close the dummy subscription
+            client.close(subId)
+        }
+
+        // Step 3: Send the event and wait for OK responses
+        val success = client.sendAndWaitForResponse(event, targetRelays, timeoutSeconds)
+
+        // Note: sendAndWaitForResponse only returns aggregate success (any relay accepted)
+        // We don't have per-relay results, so relayResults is empty
+        return BroadcastResult(
+            success = success,
+            relayResults = emptyMap(),
+            message = if (success) "Event accepted by at least one relay" else "No relay accepted the event",
+        )
+    }
+
+    /**
+     * Wait for target relays to appear in connectedRelaysFlow.
+     */
+    private suspend fun waitForRelays(
+        targetRelays: Set<NormalizedRelayUrl>,
+        timeoutMs: Long,
+    ): Set<NormalizedRelayUrl> {
+        val startTime = System.currentTimeMillis()
+        val pollInterval = 200L
+
+        while (System.currentTimeMillis() - startTime < timeoutMs) {
+            val connected = client.connectedRelaysFlow().value
+            val targetConnected = targetRelays.intersect(connected)
+
+            if (targetConnected.size == targetRelays.size) {
+                return targetConnected
+            }
+
+            // At least one connected is good enough after half the timeout
+            if (targetConnected.isNotEmpty() && System.currentTimeMillis() - startTime > timeoutMs / 2) {
+                return targetConnected
+            }
+
+            delay(pollInterval)
+        }
+
+        return client.connectedRelaysFlow().value.intersect(targetRelays)
+    }
+}