voice: waveform recording + display, playback wiring

- voice_recorder: waveform_levels[100] accumulated during feed, normalized to 100 values in stop()
  stored as 'wf=...;dur=...;' in chat_msg_submit data
- bridge: filePath in get_messages_json from local_attrs.fp, g_db_path moved global
- Message model: waveform: List<Float>, voiceDurationMs: Int, filePath: String
- VoiceBubble: Canvas waveform (100 bars, log scale), play button, duration
- ChatViewModel.playVoiceMessage → AudioRecorderManager.playVoiceFile

tools/chatgui-android/app/src/main/java/com/utun/chat/data/ChatRepository.kt

@@ -7,7 +7,9 @@ import org.json.JSONObject
 data class Channel(val id: String, val name: String, val lastMsgAt: Long = 0, val lastMsg: String = "",
                    val peersOnline: Int = 0)
 data class Message(val id: Long, val author: String, val text: String, val ts: Long,
-                   val isOutgoing: Boolean = false, val contentType: String = "text/plain")
+                   val isOutgoing: Boolean = false, val contentType: String = "text/plain",
+                   val filePath: String = "", val waveform: List<Float> = emptyList(),
+                   val voiceDurationMs: Int = 0)
 
 class ChatRepository {
     private val myNodeId: Long = NativeLib.getMyNodeId()
@@ -47,13 +49,35 @@ class ChatRepository {
             val arr = JSONArray(NativeLib.getMessages(channelId, limit))
             for (i in 0 until arr.length()) {
                 val obj = arr.getJSONObject(i)
+                val text = obj.optString("text", "")
+                val contentType = obj.optString("contentType", "text/plain")
+                val filePath = obj.optString("filePath", "")
+
+                /* Parse waveform from voice message text (format: "wf=0.1,0.2,...;dur=1234;") */
+                var waveform = emptyList<Float>()
+                var voiceDurationMs = 0
+                if (contentType == "audio/opus" && text.startsWith("wf=")) {
+                    try {
+                        val wfEnd = text.indexOf(";dur=")
+                        if (wfEnd > 0) {
+                            val wfPart = text.substring(3, wfEnd)
+                            waveform = wfPart.split(",").map { it.toFloat() }
+                            val durPart = text.substring(wfEnd + 5).takeWhile { it != ';' }
+                            voiceDurationMs = durPart.toIntOrNull() ?: 0
+                        }
+                    } catch (_: Exception) {}
+                }
+
                 list.add(Message(
                     id = obj.getLong("id"),
                     author = obj.getString("author"),
-                    text = obj.getString("text"),
+                    text = text,
                     ts = obj.getLong("ts"),
                     isOutgoing = obj.optBoolean("isOutgoing", false),
-                    contentType = obj.optString("contentType", "text/plain")
+                    contentType = contentType,
+                    filePath = filePath,
+                    waveform = waveform,
+                    voiceDurationMs = voiceDurationMs
                 ))
             }
         } catch (e: Exception) { Log.w("utun-gui", "getMessages error", e) }

tools/chatgui-android/app/src/main/java/com/utun/chat/ui/components/MessageBubble.kt

@@ -4,6 +4,7 @@ import android.Manifest
 import android.content.pm.PackageManager
 import androidx.activity.compose.rememberLauncherForActivityResult
 import androidx.activity.result.contract.ActivityResultContracts
+import androidx.compose.foundation.Canvas
 import androidx.compose.foundation.background
 import androidx.compose.foundation.clickable
 import androidx.compose.foundation.layout.*
@@ -14,6 +15,8 @@ import androidx.compose.runtime.*
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.geometry.Size
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.input.pointer.pointerInput
 import androidx.compose.ui.platform.LocalConfiguration
@@ -22,13 +25,14 @@ import androidx.compose.ui.platform.LocalDensity
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
+import kotlin.math.log10
 import androidx.core.content.ContextCompat
 import com.utun.chat.data.Message
 import com.utun.chat.data.NativeLib
 import kotlinx.coroutines.delay
 
 @Composable
-fun MessageBubble(message: Message) {
+fun MessageBubble(message: Message, onPlayVoice: (String) -> Unit = {}) {
     val bgColor = if (message.isOutgoing) Color(0xFF4A90D9) else Color(0xFFE8E8E8)
     val textColor = if (message.isOutgoing) Color.White else Color.Black
     val alignment = if (message.isOutgoing) Arrangement.End else Arrangement.Start
@@ -48,21 +52,15 @@ fun MessageBubble(message: Message) {
                 .background(bgColor)
                 .padding(12.dp)
         ) {
-            Text(message.author, fontSize = 13.sp, fontWeight = FontWeight.Bold, color = textColor.copy(alpha = 0.7f))
+            if (!isVoice) Text(message.author, fontSize = 13.sp, fontWeight = FontWeight.Bold, color = textColor.copy(alpha = 0.7f))
             Spacer(Modifier.height(2.dp))
 
             when {
-                isVoice -> {
-                    Row(verticalAlignment = Alignment.CenterVertically) {
-                        Text("\u25B6", fontSize = 20.sp, color = textColor)
-                        Spacer(Modifier.width(8.dp))
-                        Text("Voice message", fontSize = 15.sp, color = textColor)
-                    }
-                }
-                isMedia -> {
-                    Text("\uD83D\uDCC4 ${message.text}", fontSize = 15.sp, color = textColor)
-                }
+                isVoice -> VoiceBubble(message, textColor, onPlayVoice)
+                isMedia -> Text("\uD83D\uDCC4 ${message.text}", fontSize = 15.sp, color = textColor)
                 else -> {
+                    Text(message.author, fontSize = 13.sp, fontWeight = FontWeight.Bold, color = textColor.copy(alpha = 0.7f))
+                    Spacer(Modifier.height(2.dp))
                     Text(message.text, fontSize = 17.sp, color = textColor)
                 }
             }
@@ -78,6 +76,62 @@ fun MessageBubble(message: Message) {
     }
 }
 
+@Composable
+private fun VoiceBubble(message: Message, textColor: Color, onPlay: (String) -> Unit) {
+    val durationSec = message.voiceDurationMs / 1000f
+    val wf = message.waveform
+    val wfCount = wf.size
+
+    Row(verticalAlignment = Alignment.CenterVertically) {
+        /* Play button */
+        Box(
+            modifier = Modifier.size(32.dp).background(Color(0xFF3390EC), CircleShape)
+                .clickable { if (message.filePath.isNotEmpty()) onPlay(message.filePath) },
+            contentAlignment = Alignment.Center
+        ) {
+            Text("\u25B6", fontSize = 14.sp, color = Color.White)
+        }
+        Spacer(Modifier.width(8.dp))
+
+        /* Waveform */
+        if (wfCount >= 2) {
+            Box(modifier = Modifier.weight(1f).height(32.dp)) {
+                Canvas(modifier = Modifier.fillMaxSize()) {
+                    val barW = size.width / wfCount
+                    val ph = size.height.toFloat()
+                    for (i in 0 until wfCount) {
+                        val v = wf[i]
+                        val db = if (v > 0.00001f) 20f * kotlin.math.log10(v.toDouble()).toFloat() else -100f
+                        val logV = ((db + 60f) / 60f).coerceIn(0f, 1f)
+                        val barH = (2f + logV * (ph - 2f)).coerceAtMost(ph)
+                        val x = i.toFloat() * barW
+                        val y = ph - barH
+                        drawRect(
+                            color = Color(0xFF3390EC).copy(alpha = 0.5f),
+                            topLeft = Offset(x, y),
+                            size = Size(barW * 0.8f, barH)
+                        )
+                    }
+                }
+            }
+            Spacer(Modifier.width(4.dp))
+        }
+
+        /* Duration */
+        Text(
+            formatDurationMs(message.voiceDurationMs),
+            fontSize = 13.sp,
+            color = textColor.copy(alpha = 0.7f),
+            modifier = Modifier.padding(start = 4.dp)
+        )
+    }
+}
+
+private fun formatDurationMs(ms: Int): String {
+    val secs = ms / 1000
+    return "%d:%02d".format(secs / 60, secs % 60)
+}
+
 private val LOCK_SWIPE_THRESHOLD_DP = 80f
 
 @Composable

tools/chatgui-android/app/src/main/java/com/utun/chat/ui/screens/ChatScreen.kt

@@ -63,7 +63,9 @@ fun ChatScreen(
             state = listState
         ) {
             items(messages.size) { idx ->
-                MessageBubble(messages[idx])
+                MessageBubble(messages[idx], onPlayVoice = { path ->
+                    viewModel.playVoiceMessage(path)
+                })
             }
             item { Spacer(Modifier.height(8.dp)) }
         }

tools/chatgui-android/app/src/main/java/com/utun/chat/viewmodel/ChatViewModel.kt

@@ -264,6 +264,11 @@ class ChatViewModel : ViewModel() {
         NativeLib.voiceSetCompressorConfig(maxGainDb, lookbackMs, lookaheadMs, riseRate, targetLevelDb)
     }
 
+    fun playVoiceMessage(filePath: String) {
+        LogManager.addLog("INFO", "VM", "play voice: $filePath")
+        audioRecorder.playVoiceFile(filePath)
+    }
+
     fun clearState() {
         repo?.close()
         repo = null