feat(media): inline audio playback with VLCJ no-video mode

Phase 9: AudioPlayer composable using VLCJ --no-video factory,
play/pause/seek controls, NoteCard splits audio from video URLs.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

desktopApp/src/jvmMain/kotlin/com/vitorpamplona/amethyst/desktop/ui/media/AudioPlayer.kt

@@ -0,0 +1,217 @@
+/*
+ * 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.desktop.ui.media
+
+import androidx.compose.foundation.background
+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.foundation.layout.size
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.MusicNote
+import androidx.compose.material.icons.filled.Pause
+import androidx.compose.material.icons.filled.PlayArrow
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Slider
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.DisposableEffect
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableFloatStateOf
+import androidx.compose.runtime.mutableLongStateOf
+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.clip
+import androidx.compose.ui.unit.dp
+import kotlinx.coroutines.delay
+import uk.co.caprica.vlcj.factory.MediaPlayerFactory
+import uk.co.caprica.vlcj.player.base.MediaPlayer
+import uk.co.caprica.vlcj.player.base.MediaPlayerEventAdapter
+
+/**
+ * Audio-only player using VLCJ with no video surface.
+ * Creates its own MediaPlayerFactory with "--no-video" flag.
+ */
+@Composable
+fun AudioPlayer(
+    url: String,
+    modifier: Modifier = Modifier,
+) {
+    var isPlaying by remember { mutableStateOf(false) }
+    var position by remember { mutableFloatStateOf(0f) }
+    var duration by remember { mutableLongStateOf(0L) }
+    var currentTime by remember { mutableLongStateOf(0L) }
+    var vlcAvailable by remember { mutableStateOf(true) }
+    var player by remember { mutableStateOf<MediaPlayer?>(null) }
+
+    DisposableEffect(url) {
+        val factory =
+            try {
+                MediaPlayerFactory("--no-video", "--no-xlib")
+            } catch (_: Exception) {
+                vlcAvailable = false
+                return@DisposableEffect onDispose {}
+            }
+
+        val mp = factory.mediaPlayers().newMediaPlayer()
+
+        mp.events().addMediaPlayerEventListener(
+            object : MediaPlayerEventAdapter() {
+                override fun playing(mediaPlayer: MediaPlayer) {
+                    isPlaying = true
+                    duration = mediaPlayer.status().length()
+                }
+
+                override fun paused(mediaPlayer: MediaPlayer) {
+                    isPlaying = false
+                }
+
+                override fun stopped(mediaPlayer: MediaPlayer) {
+                    isPlaying = false
+                }
+
+                override fun positionChanged(
+                    mediaPlayer: MediaPlayer,
+                    newPosition: Float,
+                ) {
+                    position = newPosition
+                    currentTime = (newPosition * duration).toLong()
+                }
+
+                override fun finished(mediaPlayer: MediaPlayer) {
+                    isPlaying = false
+                    position = 0f
+                    currentTime = 0L
+                }
+            },
+        )
+
+        player = mp
+
+        onDispose {
+            player = null
+            try {
+                mp.controls().stop()
+                mp.release()
+            } catch (_: Exception) {
+                // Ignore
+            }
+            try {
+                factory.release()
+            } catch (_: Exception) {
+                // Ignore
+            }
+        }
+    }
+
+    // Position polling
+    LaunchedEffect(isPlaying) {
+        while (isPlaying) {
+            delay(500)
+            player?.let {
+                position = it.status().position()
+                currentTime = it.status().time()
+            }
+        }
+    }
+
+    if (!vlcAvailable) {
+        Text(
+            "Audio: $url (install VLC to play)",
+            style = MaterialTheme.typography.bodySmall,
+            color = MaterialTheme.colorScheme.onSurfaceVariant,
+            modifier = modifier,
+        )
+        return
+    }
+
+    Row(
+        modifier =
+            modifier
+                .fillMaxWidth()
+                .clip(RoundedCornerShape(8.dp))
+                .background(MaterialTheme.colorScheme.surfaceContainerHigh)
+                .padding(horizontal = 8.dp, vertical = 4.dp),
+        verticalAlignment = Alignment.CenterVertically,
+        horizontalArrangement = Arrangement.spacedBy(8.dp),
+    ) {
+        Icon(
+            Icons.Default.MusicNote,
+            contentDescription = null,
+            modifier = Modifier.size(20.dp),
+            tint = MaterialTheme.colorScheme.primary,
+        )
+
+        IconButton(
+            onClick = {
+                player?.let { p ->
+                    if (isPlaying) {
+                        p.controls().pause()
+                    } else {
+                        if (position <= 0f && !p.status().isPlaying) {
+                            p.media().play(url)
+                        } else {
+                            p.controls().play()
+                        }
+                    }
+                }
+            },
+            modifier = Modifier.size(32.dp),
+        ) {
+            Icon(
+                if (isPlaying) Icons.Default.Pause else Icons.Default.PlayArrow,
+                contentDescription = if (isPlaying) "Pause" else "Play",
+                modifier = Modifier.size(20.dp),
+            )
+        }
+
+        Text(
+            text = formatAudioTime(currentTime),
+            style = MaterialTheme.typography.labelSmall,
+        )
+
+        Slider(
+            value = position,
+            onValueChange = { player?.controls()?.setPosition(it) },
+            modifier = Modifier.weight(1f),
+        )
+
+        Text(
+            text = formatAudioTime(duration),
+            style = MaterialTheme.typography.labelSmall,
+        )
+    }
+}
+
+private fun formatAudioTime(millis: Long): String {
+    val totalSeconds = millis / 1000
+    val minutes = totalSeconds / 60
+    val seconds = totalSeconds % 60
+    return "%d:%02d".format(minutes, seconds)
+}

desktopApp/src/jvmMain/kotlin/com/vitorpamplona/amethyst/desktop/ui/note/NoteCard.kt

@@ -54,6 +54,7 @@ import com.vitorpamplona.amethyst.commons.richtext.UrlParser
 import com.vitorpamplona.amethyst.commons.richtext.Urls
 import com.vitorpamplona.amethyst.commons.ui.components.UserAvatar
 import com.vitorpamplona.amethyst.commons.util.toTimeAgo
+import com.vitorpamplona.amethyst.desktop.ui.media.AudioPlayer
 import com.vitorpamplona.amethyst.desktop.ui.media.DesktopVideoPlayer
 
 /**
@@ -85,11 +86,27 @@ fun NoteCard(
         remember(urls) {
             urls.withScheme.filter { RichTextParser.isImageUrl(it) }
         }
-    val videoUrls =
+    val allMediaUrls =
         remember(urls) {
             urls.withScheme.filter { RichTextParser.isVideoUrl(it) }
         }
-    val mediaUrls = remember(imageUrls, videoUrls) { (imageUrls + videoUrls).toSet() }
+    val audioExtensions = setOf("mp3", "ogg", "wav", "flac", "aac", "opus", "m4a")
+    val audioUrls =
+        remember(allMediaUrls) {
+            allMediaUrls.filter { url ->
+                val ext =
+                    url
+                        .substringAfterLast('.', "")
+                        .substringBefore('?')
+                        .lowercase()
+                ext in audioExtensions
+            }
+        }
+    val videoUrls =
+        remember(allMediaUrls, audioUrls) {
+            allMediaUrls - audioUrls.toSet()
+        }
+    val mediaUrls = remember(imageUrls, allMediaUrls) { (imageUrls + allMediaUrls).toSet() }
     val strippedContent =
         remember(note.content, mediaUrls) {
             var text = note.content
@@ -214,6 +231,22 @@ fun NoteCard(
                 }
             }
 
+            // Inline audio
+            if (audioUrls.isNotEmpty()) {
+                if (strippedContent.isNotBlank() || imageUrls.isNotEmpty() || videoUrls.isNotEmpty()) {
+                    Spacer(Modifier.height(8.dp))
+                }
+                for (url in audioUrls) {
+                    AudioPlayer(
+                        url = url,
+                        modifier = Modifier.fillMaxWidth(),
+                    )
+                    if (url != audioUrls.last()) {
+                        Spacer(Modifier.height(4.dp))
+                    }
+                }
+            }
+
             Spacer(Modifier.height(8.dp))
 
             HorizontalDivider(color = MaterialTheme.colorScheme.outline.copy(alpha = 0.3f))