fix: DASH multi-phase progress + HLS fragment progress + indeterminate animation

backend/app/services/downloader.py

@@ -39,17 +39,38 @@ def cleanup_task(task_id: str):
 
 
 def _make_hook(task_id: str):
-    """yt-dlp progress hook with real-time tracking and cancel support."""
+    """yt-dlp progress hook: handles DASH multi-phase + HLS fragments + cancel."""
+    state = {"phase": 0}          # counts "finished" events (video phase, audio phase…)
+    PHASE_WEIGHTS = [0.80, 0.19]  # phase-0 → 0-80%, phase-1 → 80-99%
+
     def hook(d):
         flag = _cancel_flags.get(task_id)
         if flag and flag.is_set():
             raise yt_dlp.utils.DownloadCancelled("Cancelled by user")
+
         if d["status"] == "downloading":
             total = d.get("total_bytes") or d.get("total_bytes_estimate") or 0
-            done = d.get("downloaded_bytes", 0)
-            _download_progress[task_id] = int(done * 100 / total) if total else 0
+            done  = d.get("downloaded_bytes", 0)
+
+            if total > 0:
+                phase_pct = done / total                        # 0.0–1.0
+            else:
+                # HLS / unknown size: use fragment index
+                fc = d.get("fragment_count") or 0
+                fi = d.get("fragment_index") or 0
+                phase_pct = (fi / fc) if fc > 0 else 0.5       # 0.5 = "working"
+
+            ph = min(state["phase"], len(PHASE_WEIGHTS) - 1)
+            base = sum(PHASE_WEIGHTS[:ph]) * 100
+            span = PHASE_WEIGHTS[ph] * 100
+            pct  = int(base + phase_pct * span)
+            _download_progress[task_id] = max(1, pct)          # at least 1 to show activity
+
         elif d["status"] == "finished":
-            _download_progress[task_id] = 99  # merging, not 100 yet
+            state["phase"] += 1
+            done_pct = int(sum(PHASE_WEIGHTS[:state["phase"]]) * 100)
+            _download_progress[task_id] = min(done_pct, 99)
+
     return hook
 
 VIDEO_BASE_PATH = os.getenv("VIDEO_BASE_PATH", "/home/xdl/xdl_videos")