voice: base64 compact waveform (100 bytes), progress bar, play/pause auto-reset

- voice_recorder: 100-char base64 (A-Za-z0-9+/) log-scale waveform, ~120 bytes total vs ~600 CSV
- ChatRepository: parse base64 'wf=<100 chars>;dur=NNNN;' → normalized 0..1 List<Float>
  CSV fallback for old messages (length < 50 or contains comma)
- VoiceBubble: progress bar (blue played / gray unplayed), ▶/⏸ toggle, elapsed timer
- onComplete callback wired through ViewModel → AudioRecorderManager → VoiceBubble auto-reset

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

@@ -53,15 +53,35 @@ class ChatRepository {
                 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;") */
+                /* Parse base64 waveform from voice message text (format: "wf=<100 chars A-Za-z0-9+/>;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 wfRaw = text.substring(3, wfEnd)  // 100 base64 chars
+                            waveform = if (wfRaw.length >= 50) {
+                                wfRaw.map { c ->
+                                    val idx = when (c) {
+                                        in 'A'..'Z' -> c - 'A'
+                                        in 'a'..'z' -> c - 'a' + 26
+                                        in '0'..'9' -> c - '0' + 52
+                                        '+' -> 62; '/' -> 63; else -> 0
+                                    }
+                                    (idx.toFloat() / 63f).coerceIn(0f, 1f)
+                                }
+                            } else {
+                                /* old CSV format fallback */
+                                val parts = wfRaw.split(",")
+                                if (parts.size >= 2) {
+                                    parts.map { s ->
+                                        val v = s.toFloatOrNull() ?: 0f
+                                        val db = if (v > 0.00001f) 20 * kotlin.math.log10(v.toDouble()).toFloat() else -100f
+                                        ((db + 60f) / 60f).coerceIn(0f, 1f)
+                                    }
+                                } else emptyList()
+                            }
                             val durPart = text.substring(wfEnd + 5).takeWhile { it != ';' }
                             voiceDurationMs = durPart.toIntOrNull() ?: 0
                         }

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

@@ -2,6 +2,7 @@ package com.utun.chat.ui.components
 
 import android.Manifest
 import android.content.pm.PackageManager
+import androidx.core.content.ContextCompat
 import androidx.activity.compose.rememberLauncherForActivityResult
 import androidx.activity.result.contract.ActivityResultContracts
 import androidx.compose.foundation.Canvas
@@ -25,14 +26,12 @@ 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, onPlayVoice: (String) -> Unit = {}) {
+fun MessageBubble(message: Message, onPlayVoice: (String, () -> Unit) -> 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
@@ -78,15 +77,29 @@ fun MessageBubble(message: Message, onPlayVoice: (String) -> Unit = {}) {
         }
     }
 }
-
 @Composable
-private fun VoiceBubble(message: Message, textColor: Color, onPlay: (String) -> Unit) {
-    val wf = message.waveform
+private fun VoiceBubble(message: Message, textColor: Color, onPlay: (String, () -> Unit) -> Unit) {
+    val wf = message.waveform  // List<Float> 0..1, 100 elements
     val wfCount = wf.size
     val durMs = message.voiceDurationMs
-    val durSec = durMs / 1000f
     var playing by remember { mutableStateOf(false) }
     var elapsedMs by remember { mutableStateOf(0) }
+    var progress by remember { mutableStateOf(0f) }
+
+    /* auto-reset on complete */
+    val onDone = remember { { playing = false; elapsedMs = 0; progress = 0f } }
+
+    /* elapsed timer while playing */
+    LaunchedEffect(playing) {
+        if (playing) {
+            val start = System.currentTimeMillis()
+            while (playing) {
+                elapsedMs = (System.currentTimeMillis() - start).toInt()
+                if (durMs > 0) progress = (elapsedMs.toFloat() / durMs.toFloat()).coerceIn(0f, 1f)
+                delay(80)
+            }
+        }
+    }
 
     Column {
         Row(verticalAlignment = Alignment.CenterVertically) {
@@ -95,9 +108,10 @@ private fun VoiceBubble(message: Message, textColor: Color, onPlay: (String) ->
                 modifier = Modifier.size(32.dp).background(Color(0xFF3390EC), CircleShape)
                     .clickable {
                         if (!playing && message.filePath.isNotEmpty()) {
-                            playing = true; elapsedMs = 0; onPlay(message.filePath)
+                            playing = true; elapsedMs = 0; progress = 0f
+                            onPlay(message.filePath, onDone)
                         } else {
-                            playing = false
+                            playing = false; onDone()
                         }
                     },
                 contentAlignment = Alignment.Center
@@ -111,15 +125,19 @@ private fun VoiceBubble(message: Message, textColor: Color, onPlay: (String) ->
                 Canvas(modifier = Modifier.weight(1f).height(28.dp)) {
                     val barW = size.width / wfCount
                     val ph = size.height
+                    val playedIdx = if (progress > 0f) (progress * wfCount).toInt() else 0
                     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 level = wf[i].coerceIn(0f, 1f)
+                        val barH = (2f + level * (ph - 2f)).coerceAtMost(ph)
                         val x = i.toFloat() * barW
                         val y = ph - barH
+                        val played = i < playedIdx
                         drawRect(
-                            color = Color(0xFF3390EC).copy(alpha = 0.35f),
+                            color = if (playing) {
+                                if (played) Color(0xFF3390EC) else Color(0xFF3390EC).copy(alpha = 0.25f)
+                            } else {
+                                Color(0xFF888899).copy(alpha = 0.45f)
+                            },
                             topLeft = Offset(x, y),
                             size = Size(barW * 0.75f, barH)
                         )
@@ -130,14 +148,15 @@ private fun VoiceBubble(message: Message, textColor: Color, onPlay: (String) ->
 
         Spacer(Modifier.height(4.dp))
 
-        /* Duration + timestamp */
+        /* Duration / elapsed + timestamp */
         Row(
             modifier = Modifier.fillMaxWidth(),
             horizontalArrangement = Arrangement.SpaceBetween,
             verticalAlignment = Alignment.Bottom
         ) {
             Text(
-                formatDurationMs(durMs),
+                if (playing) "${formatDurationMs(elapsedMs)} / ${formatDurationMs(durMs)}"
+                else formatDurationMs(durMs),
                 fontSize = 12.sp,
                 color = textColor.copy(alpha = 0.55f)
             )

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

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

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

@@ -264,9 +264,9 @@ class ChatViewModel : ViewModel() {
         NativeLib.voiceSetCompressorConfig(maxGainDb, lookbackMs, lookaheadMs, riseRate, targetLevelDb)
     }
 
-    fun playVoiceMessage(filePath: String) {
+    fun playVoiceMessage(filePath: String, onComplete: () -> Unit) {
         LogManager.addLog("INFO", "VM", "play voice: $filePath")
-        audioRecorder.playVoiceFile(filePath)
+        audioRecorder.playVoiceFile(filePath, onComplete = onComplete)
     }
 
     fun clearState() {

tools/chatgui-android/libutun_lite/voice_recorder.c

@@ -396,26 +396,26 @@ int voice_recorder_stop(int* out_duration_ms) {
     fclose(src);
     unlink(temp_path);
 
-    /* build and post chat_msg_submit with waveform data */
-    char wf_buf[1024];
-    int wf_off = 0;
+    /* build compact waveform: 100 bytes base64 (A-Za-z0-9+/), log scale */
+    static const char b64_table[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+    char wf_data[256];
+    snprintf(wf_data, sizeof(wf_data), "wf=");
+    int wf_off = 3;
     {   int wfN = g_rec->waveform_count > 0 ? g_rec->waveform_count : 1;
-        int step100 = wfN > 100 ? wfN : 100;
         for (int i = 0; i < 100; i++) {
             int s = i * wfN / 100, e = (i + 1) * wfN / 100;
             if (s >= wfN) s = wfN - 1; if (e <= s) e = s + 1; if (e > wfN) e = wfN;
             float sum = 0; int cnt = 0;
             for (int j = s; j < e; j++) { sum += g_rec->waveform_levels[j]; cnt++; }
             float v = cnt > 0 ? sum / cnt : 0;
-            if (i > 0) wf_off += snprintf(wf_buf + wf_off, sizeof(wf_buf) - wf_off, ",");
-            wf_off += snprintf(wf_buf + wf_off, sizeof(wf_buf) - wf_off, "%.3f", v);
+            float db = v > 0.00001f ? 20.0f * log10f(v) : -100.0f;
+            int idx = (int)((db + 60.0f) / 60.0f * 64.0f);
+            if (idx < 0) idx = 0; if (idx > 63) idx = 63;
+            wf_data[wf_off++] = b64_table[idx];
         }
     }
-
-    char wf_data[1280];
-    int wf_data_len = snprintf(wf_data, sizeof(wf_data), "wf=%s;dur=%lld;", wf_buf, (long long)elapsed_ms);
-
-    size_t total_data_len = (size_t)wf_data_len;
+    wf_off += snprintf(wf_data + wf_off, sizeof(wf_data) - wf_off, ";dur=%lld;", (long long)elapsed_ms);
+    size_t total_data_len = (size_t)(wf_off);
     struct chat_msg_submit* req = u_calloc(1, sizeof(struct chat_msg_submit) + total_data_len + 1);
     if (!req) { voice_cleanup_locked(g_rec); pthread_mutex_unlock(&g_rec->mtx); pthread_mutex_unlock(&g_init_mtx); return -1; }