android: hide download overlay on locally available photos

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

@@ -454,10 +454,22 @@ private fun ImageBubble(message: Message, textColor: Color,
 
     var bmp by remember(message.filePath) { mutableStateOf<Bitmap?>(null) }
 
+    LaunchedEffect(message.id, message.filePath, message.downloadState) {
+        LogManager.addLog("DEBUG", "Image", "Preview state id=${message.id} state=${message.downloadState} " +
+            "local=$downloaded downloadControl=${!downloaded}")
+    }
     LaunchedEffect(message.filePath) {
         if (message.filePath.isNotEmpty()) {
             bmp = withContext(Dispatchers.IO) {
-                try { PhotoUtil.decodeOriented(message.filePath, 2) } catch (_: Exception) { null }
+                try {
+                    val image = PhotoUtil.decodeOriented(message.filePath, 2)
+                    if (image == null) LogManager.addLog("WARN", "Image", "Preview decode failed id=${message.id} path=${message.filePath}")
+                    else LogManager.addLog("DEBUG", "Image", "Preview ready id=${message.id} size=${image.width}x${image.height}")
+                    image
+                } catch (e: Exception) {
+                    LogManager.addLog("WARN", "Image", "Preview decode failed id=${message.id} path=${message.filePath}: ${e.message}")
+                    null
+                }
             }
         }
     }
@@ -480,10 +492,10 @@ private fun ImageBubble(message: Message, textColor: Color,
                 .background(Color(0xFF1E1E23))
         ) {
             bmp?.let { Image(it.asImageBitmap(), contentDescription = null, contentScale = ContentScale.Crop, modifier = Modifier.fillMaxSize()) }
-            Box(modifier = Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
+            if (!downloaded) Box(modifier = Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
                 Box(modifier = Modifier.size(44.dp).background(Color(0xCC000000), CircleShape), contentAlignment = Alignment.Center) {
                     Text(
-                        when { downloading -> "\u23F3"; isError -> "\u267B"; !downloaded -> "\u2B07"; else -> "" },
+                        when { downloading -> "\u23F3"; isError -> "\u267B"; else -> "\u2B07" },
                         fontSize = 18.sp, color = Color.White
                     )
                 }