feat: add participant to existing call + comprehensive call previews

Add ability to invite new users into an ongoing call:
- CallManager.invitePeer() sends a call offer to a new peer using
  the current callId, adding them to pendingPeerPubKeys
- CallController.invitePeer() exposes this to the UI layer
- Add PersonAdd button to connected call controls
- Add AddParticipantDialog with user search (reuses UserSuggestionState)
- New strings: call_add_participant, call_search_users

Rewrite CallScreenPreviews to showcase all call states:
1. Offering P2P call (Calling...)
2. Offering group call (3 avatars)
3. Connecting
4. Incoming voice call
5. Incoming video call
6. Incoming group call (4 avatars)
7. Connected P2P voice call with controls
8. Connected muted + video + speaker
9. Connected group call with pending peers
10. Connected with Bluetooth audio
11. Call ended
12. Large group (5+ members, +N badge)
13. PiP calling
14. PiP connected

https://claude.ai/code/session_01LR8NmFGdMoDTVcfKjL7HWR

amethyst/src/main/java/com/vitorpamplona/amethyst/service/call/CallController.kt

@@ -337,6 +337,17 @@ class CallController(
 
     fun getEglBase() = webRtcSession?.eglBase
 
+    fun invitePeer(peerPubKey: String) {
+        scope.launch {
+            val session = webRtcSession ?: return@launch
+            session.createOffer { sdp ->
+                scope.launch {
+                    callManager.invitePeer(peerPubKey, sdp.description)
+                }
+            }
+        }
+    }
+
     fun hangup() {
         scope.launch {
             callManager.hangup()

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/call/CallScreen.kt

@@ -44,22 +44,27 @@ import androidx.compose.material.icons.filled.Call
 import androidx.compose.material.icons.filled.CallEnd
 import androidx.compose.material.icons.filled.Mic
 import androidx.compose.material.icons.filled.MicOff
+import androidx.compose.material.icons.filled.PersonAdd
 import androidx.compose.material.icons.filled.Videocam
 import androidx.compose.material.icons.filled.VideocamOff
 import androidx.compose.material.icons.filled.VolumeOff
 import androidx.compose.material.icons.filled.VolumeUp
+import androidx.compose.material3.AlertDialog
 import androidx.compose.material3.FloatingActionButton
 import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
 import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedTextField
 import androidx.compose.material3.Snackbar
 import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.DisposableEffect
 import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableLongStateOf
+import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.runtime.setValue
@@ -81,6 +86,8 @@ import com.vitorpamplona.amethyst.service.call.CallController
 import com.vitorpamplona.amethyst.ui.note.BaseUserPicture
 import com.vitorpamplona.amethyst.ui.note.ClickableUserPicture
 import com.vitorpamplona.amethyst.ui.note.UsernameDisplay
+import com.vitorpamplona.amethyst.ui.note.creators.userSuggestions.ShowUserSuggestionList
+import com.vitorpamplona.amethyst.ui.note.creators.userSuggestions.UserSuggestionState
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.AccountViewModel
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.rooms.LoadUser
 import com.vitorpamplona.amethyst.ui.stringRes
@@ -181,6 +188,7 @@ fun CallScreen(
                         onToggleMute = { callController?.toggleAudioMute() },
                         onToggleVideo = { callController?.toggleVideo() },
                         onCycleAudioRoute = { callController?.cycleAudioRoute() },
+                        onInvitePeer = { peerPubKey -> callController?.invitePeer(peerPubKey) },
                     )
                 }
             }
@@ -363,6 +371,7 @@ private fun ConnectedCallUI(
     onToggleMute: () -> Unit,
     onToggleVideo: () -> Unit,
     onCycleAudioRoute: () -> Unit,
+    onInvitePeer: (String) -> Unit = {},
 ) {
     var elapsed by remember { mutableLongStateOf(0L) }
 
@@ -384,6 +393,20 @@ private fun ConnectedCallUI(
     val isVideoEnabled by (callController?.isVideoEnabled ?: defaultTrue).collectAsState()
     val currentAudioRoute by (callController?.audioRoute ?: defaultRoute).collectAsState()
 
+    var showAddParticipant by remember { mutableStateOf(false) }
+
+    if (showAddParticipant) {
+        AddParticipantDialog(
+            accountViewModel = accountViewModel,
+            existingPeers = state.allPeerPubKeys,
+            onInvite = { peerPubKey ->
+                onInvitePeer(peerPubKey)
+                showAddParticipant = false
+            },
+            onDismiss = { showAddParticipant = false },
+        )
+    }
+
     Box(
         modifier =
             Modifier
@@ -529,6 +552,17 @@ private fun ConnectedCallUI(
                         modifier = Modifier.size(28.dp),
                     )
                 }
+                IconButton(
+                    onClick = { showAddParticipant = true },
+                    modifier = Modifier.size(56.dp),
+                ) {
+                    Icon(
+                        imageVector = Icons.Default.PersonAdd,
+                        contentDescription = stringRes(R.string.call_add_participant),
+                        tint = Color.White,
+                        modifier = Modifier.size(28.dp),
+                    )
+                }
             }
             Spacer(modifier = Modifier.height(24.dp))
             FloatingActionButton(
@@ -682,6 +716,57 @@ private fun PipConnectedCallUI(
     }
 }
 
+@Composable
+private fun AddParticipantDialog(
+    accountViewModel: AccountViewModel,
+    existingPeers: Set<String>,
+    onInvite: (String) -> Unit,
+    onDismiss: () -> Unit,
+) {
+    val userSuggestions =
+        remember {
+            UserSuggestionState(accountViewModel.account, accountViewModel.nip05ClientBuilder())
+        }
+    var searchText by remember { mutableStateOf("") }
+
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text(stringRes(R.string.call_add_participant)) },
+        text = {
+            Column {
+                OutlinedTextField(
+                    value = searchText,
+                    onValueChange = {
+                        searchText = it
+                        userSuggestions.processCurrentWord(it)
+                    },
+                    label = { Text(stringRes(R.string.call_search_users)) },
+                    singleLine = true,
+                    modifier = Modifier.fillMaxWidth(),
+                )
+                Spacer(modifier = Modifier.height(8.dp))
+                Box(modifier = Modifier.height(300.dp)) {
+                    ShowUserSuggestionList(
+                        userSuggestions = userSuggestions,
+                        onSelect = { user ->
+                            if (user.pubkeyHex !in existingPeers) {
+                                onInvite(user.pubkeyHex)
+                            }
+                        },
+                        accountViewModel = accountViewModel,
+                    )
+                }
+            }
+        },
+        confirmButton = {},
+        dismissButton = {
+            TextButton(onClick = onDismiss) {
+                Text(stringRes(R.string.call_dismiss))
+            }
+        },
+    )
+}
+
 @Composable
 private fun GroupCallPictures(
     peerPubKeys: Set<String>,

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/call/CallScreenPreviews.kt

@@ -33,11 +33,13 @@ import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.BluetoothAudio
 import androidx.compose.material.icons.filled.Call
 import androidx.compose.material.icons.filled.CallEnd
 import androidx.compose.material.icons.filled.Mic
 import androidx.compose.material.icons.filled.MicOff
 import androidx.compose.material.icons.filled.Person
+import androidx.compose.material.icons.filled.PersonAdd
 import androidx.compose.material.icons.filled.Videocam
 import androidx.compose.material.icons.filled.VideocamOff
 import androidx.compose.material.icons.filled.VolumeOff
@@ -57,8 +59,142 @@ import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
 import com.vitorpamplona.amethyst.ui.theme.ThemeComparisonColumn
 
+// ---- Shared building blocks for previews ----
+
 @Composable
-private fun PreviewCallInProgress(statusText: String) {
+private fun PreviewAvatar(
+    modifier: Modifier = Modifier,
+    tint: Color = MaterialTheme.colorScheme.onSurfaceVariant,
+) {
+    Icon(
+        Icons.Default.Person,
+        contentDescription = null,
+        modifier = modifier.size(120.dp),
+        tint = tint,
+    )
+}
+
+@Composable
+private fun PreviewGroupAvatars(
+    count: Int,
+    tint: Color = MaterialTheme.colorScheme.onSurfaceVariant,
+) {
+    val halfSize = 60.dp
+    Box(Modifier.size(120.dp)) {
+        repeat(minOf(count, 4)) { i ->
+            val alignment =
+                when (i) {
+                    0 -> Alignment.BottomStart
+                    1 -> Alignment.TopStart
+                    2 -> Alignment.BottomEnd
+                    else -> Alignment.TopEnd
+                }
+            if (i < 3 || count <= 4) {
+                Icon(
+                    Icons.Default.Person,
+                    contentDescription = null,
+                    modifier = Modifier.size(halfSize).align(alignment),
+                    tint = tint,
+                )
+            } else {
+                Box(
+                    modifier =
+                        Modifier
+                            .size(halfSize)
+                            .align(alignment)
+                            .background(
+                                MaterialTheme.colorScheme.surfaceVariant,
+                                CircleShape,
+                            ),
+                    contentAlignment = Alignment.Center,
+                ) {
+                    Text(
+                        text = "+${count - 3}",
+                        fontWeight = FontWeight.Bold,
+                        fontSize = 14.sp,
+                    )
+                }
+            }
+        }
+    }
+}
+
+@Composable
+private fun PreviewCallControls(
+    isMuted: Boolean = false,
+    isVideoEnabled: Boolean = false,
+    audioRoute: String = "earpiece",
+    showAddParticipant: Boolean = false,
+) {
+    Column(horizontalAlignment = Alignment.CenterHorizontally) {
+        Row(
+            modifier = Modifier.fillMaxWidth(),
+            horizontalArrangement = Arrangement.SpaceEvenly,
+        ) {
+            IconButton(onClick = {}, modifier = Modifier.size(56.dp)) {
+                Icon(
+                    imageVector = if (isMuted) Icons.Default.MicOff else Icons.Default.Mic,
+                    contentDescription = "Mute",
+                    tint = if (isMuted) Color.Red else Color.White,
+                    modifier = Modifier.size(28.dp),
+                )
+            }
+            IconButton(onClick = {}, modifier = Modifier.size(56.dp)) {
+                Icon(
+                    imageVector = if (isVideoEnabled) Icons.Default.Videocam else Icons.Default.VideocamOff,
+                    contentDescription = "Camera",
+                    tint = if (!isVideoEnabled) Color.Red else Color.White,
+                    modifier = Modifier.size(28.dp),
+                )
+            }
+            IconButton(onClick = {}, modifier = Modifier.size(56.dp)) {
+                Icon(
+                    imageVector =
+                        when (audioRoute) {
+                            "speaker" -> Icons.Default.VolumeUp
+                            "bluetooth" -> Icons.Default.BluetoothAudio
+                            else -> Icons.Default.VolumeOff
+                        },
+                    contentDescription = "Audio route",
+                    tint =
+                        when (audioRoute) {
+                            "speaker" -> Color.Cyan
+                            "bluetooth" -> Color(0xFF2196F3)
+                            else -> Color.White
+                        },
+                    modifier = Modifier.size(28.dp),
+                )
+            }
+            if (showAddParticipant) {
+                IconButton(onClick = {}, modifier = Modifier.size(56.dp)) {
+                    Icon(
+                        Icons.Default.PersonAdd,
+                        contentDescription = "Add participant",
+                        tint = Color.White,
+                        modifier = Modifier.size(28.dp),
+                    )
+                }
+            }
+        }
+        Spacer(modifier = Modifier.height(24.dp))
+        FloatingActionButton(
+            onClick = {},
+            containerColor = Color.Red,
+            shape = CircleShape,
+            modifier = Modifier.size(64.dp),
+        ) {
+            Icon(Icons.Default.CallEnd, "Hang up", tint = Color.White, modifier = Modifier.size(32.dp))
+        }
+    }
+}
+
+// ---- 1. Offering (Calling...) ----
+
+@Composable
+private fun PreviewCallInProgress(
+    name: String,
+    statusText: String,
+) {
     Box(
         modifier =
             Modifier
@@ -70,24 +206,11 @@ private fun PreviewCallInProgress(statusText: String) {
             horizontalAlignment = Alignment.CenterHorizontally,
             verticalArrangement = Arrangement.Center,
         ) {
-            Icon(
+            PreviewAvatar()
-                Icons.Default.Person,
-                contentDescription = null,
-                modifier = Modifier.size(120.dp),
-                tint = MaterialTheme.colorScheme.onSurfaceVariant,
-            )
             Spacer(modifier = Modifier.height(16.dp))
-            Text(
+            Text(text = name, fontWeight = FontWeight.Bold, fontSize = 20.sp)
-                text = "Alice",
-                fontWeight = FontWeight.Bold,
-                fontSize = 20.sp,
-            )
             Spacer(modifier = Modifier.height(8.dp))
-            Text(
+            Text(text = statusText, color = MaterialTheme.colorScheme.onSurfaceVariant, fontSize = 16.sp)
-                text = statusText,
-                color = MaterialTheme.colorScheme.onSurfaceVariant,
-                fontSize = 16.sp,
-            )
             Spacer(modifier = Modifier.height(48.dp))
             FloatingActionButton(
                 onClick = {},
@@ -95,12 +218,7 @@ private fun PreviewCallInProgress(statusText: String) {
                 shape = CircleShape,
                 modifier = Modifier.size(64.dp),
             ) {
-                Icon(
+                Icon(Icons.Default.CallEnd, "Hang up", tint = Color.White, modifier = Modifier.size(32.dp))
-                    Icons.Default.CallEnd,
-                    contentDescription = "Hang up",
-                    tint = Color.White,
-                    modifier = Modifier.size(32.dp),
-                )
             }
         }
     }
@@ -110,29 +228,15 @@ private fun PreviewCallInProgress(statusText: String) {
 @Composable
 fun PreviewCallingScreen() {
     ThemeComparisonColumn {
-        PreviewCallInProgress("Calling...")
+        PreviewCallInProgress("Alice", "Calling\u2026")
     }
 }
 
-@Preview(showBackground = true, widthDp = 360, heightDp = 640)
+// ---- 2. Offering group call ----
-@Composable
-fun PreviewConnectingScreen() {
-    ThemeComparisonColumn {
-        PreviewCallInProgress("Connecting...")
-    }
-}
 
 @Preview(showBackground = true, widthDp = 360, heightDp = 640)
 @Composable
-fun PreviewCallEndedScreen() {
+fun PreviewCallingGroupScreen() {
-    ThemeComparisonColumn {
-        PreviewCallInProgress("Call ended")
-    }
-}
-
-@Preview(showBackground = true, widthDp = 360, heightDp = 640)
-@Composable
-fun PreviewIncomingCallScreen() {
     ThemeComparisonColumn {
         Box(
             modifier =
@@ -145,53 +249,64 @@ fun PreviewIncomingCallScreen() {
                 horizontalAlignment = Alignment.CenterHorizontally,
                 verticalArrangement = Arrangement.Center,
             ) {
-                Icon(
+                PreviewGroupAvatars(3)
-                    Icons.Default.Person,
-                    contentDescription = null,
-                    modifier = Modifier.size(120.dp),
-                    tint = MaterialTheme.colorScheme.onSurfaceVariant,
-                )
                 Spacer(modifier = Modifier.height(16.dp))
-                Text(
+                Text("Alice, Bob +1", fontWeight = FontWeight.Bold, fontSize = 20.sp)
-                    text = "Bob",
-                    fontWeight = FontWeight.Bold,
-                    fontSize = 20.sp,
-                )
                 Spacer(modifier = Modifier.height(8.dp))
-                Text(
+                Text("Calling\u2026", color = MaterialTheme.colorScheme.onSurfaceVariant, fontSize = 16.sp)
-                    text = "Incoming voice call...",
-                    color = MaterialTheme.colorScheme.onSurfaceVariant,
-                    fontSize = 16.sp,
-                )
                 Spacer(modifier = Modifier.height(48.dp))
-                Row(
+                FloatingActionButton(
-                    horizontalArrangement = Arrangement.spacedBy(48.dp),
+                    onClick = {},
+                    containerColor = Color.Red,
+                    shape = CircleShape,
+                    modifier = Modifier.size(64.dp),
                 ) {
-                    FloatingActionButton(
+                    Icon(Icons.Default.CallEnd, "Hang up", tint = Color.White, modifier = Modifier.size(32.dp))
-                        onClick = {},
+                }
-                        containerColor = Color.Red,
+            }
-                        shape = CircleShape,
+        }
-                        modifier = Modifier.size(64.dp),
+    }
-                    ) {
+}
-                        Icon(
+
-                            Icons.Default.CallEnd,
+// ---- 3. Connecting ----
-                            contentDescription = "Reject",
+
-                            tint = Color.White,
+@Preview(showBackground = true, widthDp = 360, heightDp = 640)
-                            modifier = Modifier.size(32.dp),
+@Composable
-                        )
+fun PreviewConnectingScreen() {
+    ThemeComparisonColumn {
+        PreviewCallInProgress("Alice", "Connecting\u2026")
+    }
+}
+
+// ---- 4. Incoming voice call ----
+
+@Preview(showBackground = true, widthDp = 360, heightDp = 640)
+@Composable
+fun PreviewIncomingVoiceCallScreen() {
+    ThemeComparisonColumn {
+        Box(
+            modifier =
+                Modifier
+                    .fillMaxSize()
+                    .background(MaterialTheme.colorScheme.surface),
+            contentAlignment = Alignment.Center,
+        ) {
+            Column(
+                horizontalAlignment = Alignment.CenterHorizontally,
+                verticalArrangement = Arrangement.Center,
+            ) {
+                PreviewAvatar()
+                Spacer(modifier = Modifier.height(16.dp))
+                Text("Bob", fontWeight = FontWeight.Bold, fontSize = 20.sp)
+                Spacer(modifier = Modifier.height(8.dp))
+                Text("Incoming voice call\u2026", color = MaterialTheme.colorScheme.onSurfaceVariant, fontSize = 16.sp)
+                Spacer(modifier = Modifier.height(48.dp))
+                Row(horizontalArrangement = Arrangement.spacedBy(48.dp)) {
+                    FloatingActionButton(onClick = {}, containerColor = Color.Red, shape = CircleShape, modifier = Modifier.size(64.dp)) {
+                        Icon(Icons.Default.CallEnd, "Reject", tint = Color.White, modifier = Modifier.size(32.dp))
                     }
-                    FloatingActionButton(
+                    FloatingActionButton(onClick = {}, containerColor = Color(0xFF4CAF50), shape = CircleShape, modifier = Modifier.size(64.dp)) {
-                        onClick = {},
+                        Icon(Icons.Default.Call, "Accept", tint = Color.White, modifier = Modifier.size(32.dp))
-                        containerColor = Color(0xFF4CAF50),
-                        shape = CircleShape,
-                        modifier = Modifier.size(64.dp),
-                    ) {
-                        Icon(
-                            Icons.Default.Call,
-                            contentDescription = "Accept",
-                            tint = Color.White,
-                            modifier = Modifier.size(32.dp),
-                        )
                     }
                 }
             }
@@ -199,6 +314,80 @@ fun PreviewIncomingCallScreen() {
     }
 }
 
+// ---- 5. Incoming video call ----
+
+@Preview(showBackground = true, widthDp = 360, heightDp = 640)
+@Composable
+fun PreviewIncomingVideoCallScreen() {
+    ThemeComparisonColumn {
+        Box(
+            modifier =
+                Modifier
+                    .fillMaxSize()
+                    .background(MaterialTheme.colorScheme.surface),
+            contentAlignment = Alignment.Center,
+        ) {
+            Column(
+                horizontalAlignment = Alignment.CenterHorizontally,
+                verticalArrangement = Arrangement.Center,
+            ) {
+                PreviewAvatar()
+                Spacer(modifier = Modifier.height(16.dp))
+                Text("Bob", fontWeight = FontWeight.Bold, fontSize = 20.sp)
+                Spacer(modifier = Modifier.height(8.dp))
+                Text("Incoming video call\u2026", color = MaterialTheme.colorScheme.onSurfaceVariant, fontSize = 16.sp)
+                Spacer(modifier = Modifier.height(48.dp))
+                Row(horizontalArrangement = Arrangement.spacedBy(48.dp)) {
+                    FloatingActionButton(onClick = {}, containerColor = Color.Red, shape = CircleShape, modifier = Modifier.size(64.dp)) {
+                        Icon(Icons.Default.CallEnd, "Reject", tint = Color.White, modifier = Modifier.size(32.dp))
+                    }
+                    FloatingActionButton(onClick = {}, containerColor = Color(0xFF4CAF50), shape = CircleShape, modifier = Modifier.size(64.dp)) {
+                        Icon(Icons.Default.Call, "Accept", tint = Color.White, modifier = Modifier.size(32.dp))
+                    }
+                }
+            }
+        }
+    }
+}
+
+// ---- 6. Incoming group call ----
+
+@Preview(showBackground = true, widthDp = 360, heightDp = 640)
+@Composable
+fun PreviewIncomingGroupCallScreen() {
+    ThemeComparisonColumn {
+        Box(
+            modifier =
+                Modifier
+                    .fillMaxSize()
+                    .background(MaterialTheme.colorScheme.surface),
+            contentAlignment = Alignment.Center,
+        ) {
+            Column(
+                horizontalAlignment = Alignment.CenterHorizontally,
+                verticalArrangement = Arrangement.Center,
+            ) {
+                PreviewGroupAvatars(4)
+                Spacer(modifier = Modifier.height(16.dp))
+                Text("Bob, Alice +2", fontWeight = FontWeight.Bold, fontSize = 20.sp)
+                Spacer(modifier = Modifier.height(8.dp))
+                Text("Incoming voice call\u2026", color = MaterialTheme.colorScheme.onSurfaceVariant, fontSize = 16.sp)
+                Spacer(modifier = Modifier.height(48.dp))
+                Row(horizontalArrangement = Arrangement.spacedBy(48.dp)) {
+                    FloatingActionButton(onClick = {}, containerColor = Color.Red, shape = CircleShape, modifier = Modifier.size(64.dp)) {
+                        Icon(Icons.Default.CallEnd, "Reject", tint = Color.White, modifier = Modifier.size(32.dp))
+                    }
+                    FloatingActionButton(onClick = {}, containerColor = Color(0xFF4CAF50), shape = CircleShape, modifier = Modifier.size(64.dp)) {
+                        Icon(Icons.Default.Call, "Accept", tint = Color.White, modifier = Modifier.size(32.dp))
+                    }
+                }
+            }
+        }
+    }
+}
+
+// ---- 7. Connected P2P voice call ----
+
 @Preview(showBackground = true, widthDp = 360, heightDp = 640)
 @Composable
 fun PreviewConnectedCallScreen() {
@@ -214,91 +403,25 @@ fun PreviewConnectedCallScreen() {
                 horizontalAlignment = Alignment.CenterHorizontally,
                 verticalArrangement = Arrangement.Center,
             ) {
-                Icon(
+                PreviewAvatar(tint = Color.White.copy(alpha = 0.5f))
-                    Icons.Default.Person,
-                    contentDescription = null,
-                    modifier = Modifier.size(120.dp),
-                    tint = Color.White.copy(alpha = 0.5f),
-                )
                 Spacer(modifier = Modifier.height(16.dp))
-                Text(
+                Text("Alice", fontWeight = FontWeight.Bold, fontSize = 20.sp, color = Color.White)
-                    text = "Alice",
-                    fontWeight = FontWeight.Bold,
-                    fontSize = 20.sp,
-                    color = Color.White,
-                )
                 Spacer(modifier = Modifier.height(8.dp))
-                Text(
+                Text("02:45", color = Color.White.copy(alpha = 0.7f), fontSize = 16.sp)
-                    text = "02:45",
-                    color = Color.White.copy(alpha = 0.7f),
-                    fontSize = 16.sp,
-                )
             }
 
             Column(
-                modifier =
+                modifier = Modifier.align(Alignment.BottomCenter).padding(bottom = 48.dp),
-                    Modifier
-                        .align(Alignment.BottomCenter)
-                        .padding(bottom = 48.dp),
                 horizontalAlignment = Alignment.CenterHorizontally,
             ) {
-                Row(
+                PreviewCallControls(showAddParticipant = true)
-                    modifier = Modifier.fillMaxWidth(),
-                    horizontalArrangement = Arrangement.SpaceEvenly,
-                ) {
-                    IconButton(
-                        onClick = {},
-                        modifier = Modifier.size(56.dp),
-                    ) {
-                        Icon(
-                            imageVector = Icons.Default.Mic,
-                            contentDescription = "Mute",
-                            tint = Color.White,
-                            modifier = Modifier.size(28.dp),
-                        )
-                    }
-                    IconButton(
-                        onClick = {},
-                        modifier = Modifier.size(56.dp),
-                    ) {
-                        Icon(
-                            imageVector = Icons.Default.VideocamOff,
-                            contentDescription = "Camera off",
-                            tint = Color.Red,
-                            modifier = Modifier.size(28.dp),
-                        )
-                    }
-                    IconButton(
-                        onClick = {},
-                        modifier = Modifier.size(56.dp),
-                    ) {
-                        Icon(
-                            imageVector = Icons.Default.VolumeOff,
-                            contentDescription = "Speaker",
-                            tint = Color.White,
-                            modifier = Modifier.size(28.dp),
-                        )
-                    }
-                }
-                Spacer(modifier = Modifier.height(24.dp))
-                FloatingActionButton(
-                    onClick = {},
-                    containerColor = Color.Red,
-                    shape = CircleShape,
-                    modifier = Modifier.size(64.dp),
-                ) {
-                    Icon(
-                        Icons.Default.CallEnd,
-                        contentDescription = "Hang up",
-                        tint = Color.White,
-                        modifier = Modifier.size(32.dp),
-                    )
-                }
             }
         }
     }
 }
 
+// ---- 8. Connected P2P muted + video + speaker ----
+
 @Preview(showBackground = true, widthDp = 360, heightDp = 640)
 @Composable
 fun PreviewConnectedCallMuted() {
@@ -314,12 +437,7 @@ fun PreviewConnectedCallMuted() {
                 horizontalAlignment = Alignment.CenterHorizontally,
                 verticalArrangement = Arrangement.Center,
             ) {
-                Icon(
+                PreviewAvatar(tint = Color.White.copy(alpha = 0.5f))
-                    Icons.Default.Person,
-                    contentDescription = null,
-                    modifier = Modifier.size(120.dp),
-                    tint = Color.White.copy(alpha = 0.5f),
-                )
                 Spacer(modifier = Modifier.height(16.dp))
                 Text("Alice", fontWeight = FontWeight.Bold, fontSize = 20.sp, color = Color.White)
                 Spacer(modifier = Modifier.height(8.dp))
@@ -327,36 +445,176 @@ fun PreviewConnectedCallMuted() {
             }
 
             Column(
-                modifier =
+                modifier = Modifier.align(Alignment.BottomCenter).padding(bottom = 48.dp),
-                    Modifier
-                        .align(Alignment.BottomCenter)
-                        .padding(bottom = 48.dp),
                 horizontalAlignment = Alignment.CenterHorizontally,
             ) {
-                Row(
+                PreviewCallControls(
-                    modifier = Modifier.fillMaxWidth(),
+                    isMuted = true,
-                    horizontalArrangement = Arrangement.SpaceEvenly,
+                    isVideoEnabled = true,
-                ) {
+                    audioRoute = "speaker",
-                    IconButton(onClick = {}, modifier = Modifier.size(56.dp)) {
+                    showAddParticipant = true,
-                        Icon(Icons.Default.MicOff, "Unmute", tint = Color.Red, modifier = Modifier.size(28.dp))
+                )
-                    }
-                    IconButton(onClick = {}, modifier = Modifier.size(56.dp)) {
-                        Icon(Icons.Default.Videocam, "Camera on", tint = Color.White, modifier = Modifier.size(28.dp))
-                    }
-                    IconButton(onClick = {}, modifier = Modifier.size(56.dp)) {
-                        Icon(Icons.Default.VolumeUp, "Earpiece", tint = Color.Cyan, modifier = Modifier.size(28.dp))
-                    }
-                }
-                Spacer(modifier = Modifier.height(24.dp))
-                FloatingActionButton(
-                    onClick = {},
-                    containerColor = Color.Red,
-                    shape = CircleShape,
-                    modifier = Modifier.size(64.dp),
-                ) {
-                    Icon(Icons.Default.CallEnd, "Hang up", tint = Color.White, modifier = Modifier.size(32.dp))
-                }
             }
         }
     }
 }
+
+// ---- 9. Connected group call with pending peers ----
+
+@Preview(showBackground = true, widthDp = 360, heightDp = 640)
+@Composable
+fun PreviewConnectedGroupCallWithPending() {
+    ThemeComparisonColumn {
+        Box(
+            modifier =
+                Modifier
+                    .fillMaxSize()
+                    .background(Color.Black),
+        ) {
+            Column(
+                modifier = Modifier.fillMaxSize(),
+                horizontalAlignment = Alignment.CenterHorizontally,
+                verticalArrangement = Arrangement.Center,
+            ) {
+                PreviewGroupAvatars(3, tint = Color.White.copy(alpha = 0.5f))
+                Spacer(modifier = Modifier.height(16.dp))
+                Text("Alice, Bob +1", fontWeight = FontWeight.Bold, fontSize = 20.sp, color = Color.White)
+                Spacer(modifier = Modifier.height(8.dp))
+                Text("01:30", color = Color.White.copy(alpha = 0.7f), fontSize = 16.sp)
+                Spacer(modifier = Modifier.height(4.dp))
+                Text("Waiting for others to join\u2026", color = Color.White.copy(alpha = 0.5f), fontSize = 13.sp)
+            }
+
+            Column(
+                modifier = Modifier.align(Alignment.BottomCenter).padding(bottom = 48.dp),
+                horizontalAlignment = Alignment.CenterHorizontally,
+            ) {
+                PreviewCallControls(showAddParticipant = true)
+            }
+        }
+    }
+}
+
+// ---- 10. Connected with Bluetooth audio ----
+
+@Preview(showBackground = true, widthDp = 360, heightDp = 640)
+@Composable
+fun PreviewConnectedCallBluetooth() {
+    ThemeComparisonColumn {
+        Box(
+            modifier =
+                Modifier
+                    .fillMaxSize()
+                    .background(Color.Black),
+        ) {
+            Column(
+                modifier = Modifier.fillMaxSize(),
+                horizontalAlignment = Alignment.CenterHorizontally,
+                verticalArrangement = Arrangement.Center,
+            ) {
+                PreviewAvatar(tint = Color.White.copy(alpha = 0.5f))
+                Spacer(modifier = Modifier.height(16.dp))
+                Text("Alice", fontWeight = FontWeight.Bold, fontSize = 20.sp, color = Color.White)
+                Spacer(modifier = Modifier.height(8.dp))
+                Text("10:03", color = Color.White.copy(alpha = 0.7f), fontSize = 16.sp)
+            }
+
+            Column(
+                modifier = Modifier.align(Alignment.BottomCenter).padding(bottom = 48.dp),
+                horizontalAlignment = Alignment.CenterHorizontally,
+            ) {
+                PreviewCallControls(audioRoute = "bluetooth", showAddParticipant = true)
+            }
+        }
+    }
+}
+
+// ---- 11. Call ended ----
+
+@Preview(showBackground = true, widthDp = 360, heightDp = 640)
+@Composable
+fun PreviewCallEndedScreen() {
+    ThemeComparisonColumn {
+        PreviewCallInProgress("Alice", "Call ended")
+    }
+}
+
+// ---- 12. Group call with 5+ members (shows +N badge) ----
+
+@Preview(showBackground = true, widthDp = 360, heightDp = 640)
+@Composable
+fun PreviewGroupCallLargeGroup() {
+    ThemeComparisonColumn {
+        Box(
+            modifier =
+                Modifier
+                    .fillMaxSize()
+                    .background(Color.Black),
+        ) {
+            Column(
+                modifier = Modifier.fillMaxSize(),
+                horizontalAlignment = Alignment.CenterHorizontally,
+                verticalArrangement = Arrangement.Center,
+            ) {
+                PreviewGroupAvatars(6, tint = Color.White.copy(alpha = 0.5f))
+                Spacer(modifier = Modifier.height(16.dp))
+                Text("Alice, Bob +4", fontWeight = FontWeight.Bold, fontSize = 20.sp, color = Color.White)
+                Spacer(modifier = Modifier.height(8.dp))
+                Text("03:21", color = Color.White.copy(alpha = 0.7f), fontSize = 16.sp)
+            }
+
+            Column(
+                modifier = Modifier.align(Alignment.BottomCenter).padding(bottom = 48.dp),
+                horizontalAlignment = Alignment.CenterHorizontally,
+            ) {
+                PreviewCallControls(showAddParticipant = true)
+            }
+        }
+    }
+}
+
+// ---- 13. PiP mode (small) ----
+
+@Preview(showBackground = true, widthDp = 200, heightDp = 120)
+@Composable
+fun PreviewPipCallUI() {
+    Box(
+        modifier =
+            Modifier
+                .fillMaxSize()
+                .background(MaterialTheme.colorScheme.surface),
+        contentAlignment = Alignment.Center,
+    ) {
+        Column(
+            horizontalAlignment = Alignment.CenterHorizontally,
+            verticalArrangement = Arrangement.Center,
+        ) {
+            Icon(Icons.Default.Person, contentDescription = null, modifier = Modifier.size(48.dp))
+            Spacer(modifier = Modifier.height(4.dp))
+            Text("Calling\u2026", fontSize = 10.sp, color = MaterialTheme.colorScheme.onSurfaceVariant)
+        }
+    }
+}
+
+// ---- 14. PiP connected (small) ----
+
+@Preview(showBackground = true, widthDp = 200, heightDp = 120)
+@Composable
+fun PreviewPipConnectedCallUI() {
+    Box(
+        modifier =
+            Modifier
+                .fillMaxSize()
+                .background(Color.Black),
+        contentAlignment = Alignment.Center,
+    ) {
+        Column(
+            horizontalAlignment = Alignment.CenterHorizontally,
+            verticalArrangement = Arrangement.Center,
+        ) {
+            Icon(Icons.Default.Person, contentDescription = null, modifier = Modifier.size(48.dp), tint = Color.White.copy(alpha = 0.5f))
+            Spacer(modifier = Modifier.height(4.dp))
+            Text("02:45", fontSize = 10.sp, color = Color.White.copy(alpha = 0.7f))
+        }
+    }
+}

amethyst/src/main/res/values/strings.xml

@@ -797,6 +797,8 @@
     <string name="call_voice">Voice call</string>
     <string name="call_video">Video call</string>
     <string name="call_waiting_for_others">Waiting for others to join\u2026</string>
+    <string name="call_add_participant">Add participant</string>
+    <string name="call_search_users">Search users\u2026</string>
     <string name="call_failed_start">Failed to start call</string>
     <string name="call_failed_accept">Failed to accept call</string>
     <string name="call_failed_session">Failed to create call session</string>

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/call/CallManager.kt

@@ -301,6 +301,36 @@ class CallManager(
             )
     }
 
+    /** Invites a new peer into the current call by sending them an offer. */
+    suspend fun invitePeer(
+        peerPubKey: HexKey,
+        sdpOffer: String,
+    ) {
+        val current = _state.value
+        val callId: String
+        val callType: CallType
+        when (current) {
+            is CallState.Connecting -> {
+                callId = current.callId
+                callType = current.callType
+                _state.value = current.copy(pendingPeerPubKeys = current.pendingPeerPubKeys + peerPubKey)
+            }
+
+            is CallState.Connected -> {
+                callId = current.callId
+                callType = current.callType
+                _state.value = current.copy(pendingPeerPubKeys = current.pendingPeerPubKeys + peerPubKey)
+            }
+
+            else -> {
+                return
+            }
+        }
+
+        val result = factory.createCallOffer(sdpOffer, peerPubKey, callId, callType, signer)
+        publishEvent(result.wrap)
+    }
+
     suspend fun hangup() {
         val peerPubKeys: Set<HexKey>
         val callId: String