fix(videos): base convert % on elapsed/duration not file size

File size ratio was wrong since output bitrate != input bitrate.
Now uses ffprobe to get video duration, then elapsed/duration for %.

Co-authored-by: Copilot <[email protected]>

modules/app_video.py

@@ -36,12 +36,25 @@ def queue_convert(relative_path, force=False):
     with _converting_lock:
         if relative_path in _converting:
             return False
-        _converting[relative_path] = {"started_at": time.time(), "source_size": 0, "tmp_path": ""}
+        _converting[relative_path] = {"started_at": time.time(), "duration_s": 0, "tmp_path": ""}
     t = threading.Thread(target=_convert_bg, args=(relative_path,), daemon=True)
     t.start()
     return True
 
 
+def _get_duration_s(path):
+    """Return video duration in seconds via ffprobe, or None on failure."""
+    try:
+        result = subprocess.run(
+            ["ffprobe", "-v", "error", "-show_entries", "format=duration",
+             "-of", "default=noprint_wrappers=1:nokey=1", path],
+            capture_output=True, text=True, timeout=10,
+        )
+        return float(result.stdout.strip())
+    except Exception:
+        return None
+
+
 def _convert_bg(relative_path):
     try:
         source_path = _local_path(relative_path)
@@ -53,10 +66,10 @@ def _convert_bg(relative_path):
 
         try:
             tmp_path = mp4_path + ".converting.mp4"
-            source_size = os.path.getsize(source_path) if os.path.exists(source_path) else 0
+            duration_s = _get_duration_s(source_path) or 0
             with _converting_lock:
                 if relative_path in _converting:
-                    _converting[relative_path]["source_size"] = source_size
+                    _converting[relative_path]["duration_s"] = duration_s
                     _converting[relative_path]["tmp_path"] = tmp_path
             cmd = [
                 "ffmpeg", "-nostdin", "-loglevel", "error", "-y",
@@ -138,18 +151,11 @@ def list_local_videos():
         convert_progress = None
         if converting and conv_info:
             elapsed = time.time() - conv_info["started_at"]
-            source_size = conv_info["source_size"]
-            tmp_path = conv_info["tmp_path"]
-            tmp_size = 0
-            if tmp_path and os.path.exists(tmp_path):
-                try:
-                    tmp_size = os.path.getsize(tmp_path)
-                except OSError:
-                    pass
-            pct = round(tmp_size / source_size * 100) if source_size > 0 else 0
+            duration_s = conv_info.get("duration_s", 0)
+            pct = min(round(elapsed / duration_s * 100), 99) if duration_s > 0 else 0
             convert_progress = {
                 "elapsed_s": int(elapsed),
-                "pct": min(pct, 99),  # never show 100% until done
+                "pct": pct,
             }
         files.append(
             {