feat: add video streaming with transcode cache and audio extraction

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/routes/stream.py

@@ -1,3 +1,50 @@
-from fastapi import APIRouter
+import os
+
+from fastapi import APIRouter, Query
+from fastapi.responses import FileResponse, JSONResponse
+
+from ..config import MEDIA_DIRS, QUALITY_PRESETS
+from .. import cache
 
 router = APIRouter()
+
+
+def _resolve_source(path: str, root: str) -> str | None:
+    if root not in MEDIA_DIRS:
+        return None
+    full = os.path.join(root, path)
+    return full if os.path.isfile(full) else None
+
+
+@router.get("/stream/{path:path}")
+def stream_video(path: str, root: str = Query(...), quality: str = Query("low")):
+    if quality not in QUALITY_PRESETS:
+        return JSONResponse({"error": f"invalid quality: {quality}"}, status_code=400)
+    source = _resolve_source(path, root)
+    if source is None:
+        return JSONResponse({"error": "not found"}, status_code=404)
+
+    status = cache.ensure_transcode(source, quality)
+    if status == cache.CacheStatus.READY:
+        return FileResponse(cache.cache_path(source, quality), media_type="video/mp4")
+    return JSONResponse({"status": status, "quality": quality}, status_code=202)
+
+
+@router.get("/audio/{path:path}")
+def stream_audio(path: str, root: str = Query(...)):
+    source = _resolve_source(path, root)
+    if source is None:
+        return JSONResponse({"error": "not found"}, status_code=404)
+
+    status = cache.ensure_audio(source)
+    if status == cache.CacheStatus.READY:
+        return FileResponse(cache.audio_cache_path(source), media_type="audio/wav")
+    return JSONResponse({"status": status}, status_code=202)
+
+
+@router.get("/cache/status/{path:path}")
+def cache_status(path: str, root: str = Query(...)):
+    source = _resolve_source(path, root)
+    if source is None:
+        return JSONResponse({"error": "not found"}, status_code=404)
+    return cache.get_all_statuses(source)