Add scheduled sync, disk space awareness, and subtitle downloads

- auto-sync daemon: background thread checks every hour and syncs followed
  channels for users with sync_interval_hours set (6/12/24h options)
- disk stats: /api/stats now returns total/used/free/download bytes;
  Stats page shows a disk usage bar
- subtitles: subtitle_langs setting (e.g. "en,sv") passed through all
  download paths; yt-dlp writes .srt files alongside the video
- Settings page: sync interval dropdown + subtitle languages input

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

backend/main.py

@@ -71,6 +71,8 @@ def on_startup():
         "ALTER TABLE user_settings ADD COLUMN feed_weight_affinity REAL DEFAULT 5.0",
         "ALTER TABLE user_settings ADD COLUMN feed_weight_channel REAL DEFAULT 5.0",
         "ALTER TABLE user_settings ADD COLUMN use_oauth2 INTEGER DEFAULT 0",
+        "ALTER TABLE user_settings ADD COLUMN sync_interval_hours INTEGER DEFAULT 0",
+        "ALTER TABLE user_settings ADD COLUMN subtitle_langs TEXT DEFAULT ''",
         """CREATE TABLE IF NOT EXISTS search_history (
             id INTEGER PRIMARY KEY AUTOINCREMENT,
             user_id INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
@@ -151,9 +153,47 @@ def on_startup():
 
     # Backfill descriptions for videos that don't have them yet (runs in background)
     import threading
-    from .routers.channels import _enrich_missing_task
+    from .routers.channels import _enrich_missing_task, _index_channels_batch
     threading.Thread(target=_enrich_missing_task, args=(3,), daemon=True).start()
 
+    def _auto_sync_daemon():
+        import time
+        from datetime import datetime, timedelta
+        from sqlalchemy import text as _text
+        while True:
+            time.sleep(3600)
+            try:
+                db = SessionLocal()
+                try:
+                    users_due = db.execute(
+                        _text("SELECT user_id, sync_interval_hours FROM user_settings WHERE sync_interval_hours > 0")
+                    ).mappings().all()
+                    for row in users_due:
+                        uid = row["user_id"]
+                        cutoff = datetime.utcnow() - timedelta(hours=row["sync_interval_hours"])
+                        ch_ids = [
+                            r["id"] for r in db.execute(
+                                _text("""
+                                    SELECT c.id FROM channels c
+                                    JOIN user_channels uc ON c.id = uc.channel_id
+                                    WHERE uc.user_id = :uid AND uc.status = 'followed'
+                                      AND (c.crawled_at IS NULL OR c.crawled_at < :cutoff)
+                                    ORDER BY COALESCE(c.crawled_at, '1970-01-01') ASC
+                                """),
+                                {"uid": uid, "cutoff": cutoff},
+                            ).mappings().all()
+                        ]
+                        if ch_ids:
+                            threading.Thread(
+                                target=_index_channels_batch, args=(ch_ids, uid), daemon=True
+                            ).start()
+                finally:
+                    db.close()
+            except Exception:
+                pass
+
+    threading.Thread(target=_auto_sync_daemon, daemon=True).start()
+
 
 @app.get("/api/health")
 def health():

backend/models.py

@@ -122,6 +122,8 @@ class UserSettings(Base):
     feed_weight_affinity = Column(Float, default=5.0)  # 0–10
     feed_weight_channel = Column(Float, default=5.0)   # 0–10
     use_oauth2 = Column(Boolean, default=False)
+    sync_interval_hours = Column(Integer, default=0)   # 0 = disabled, 6/12/24 = auto-sync interval
+    subtitle_langs = Column(String, default="")        # "" = disabled, "en", "en,sv", etc.
 
 
 class DiscoveryQueue(Base):

backend/routers/channels.py

@@ -147,6 +147,7 @@ def _index_channel_task(channel_id: int, user_id: int):
 
             if channel_auto:
                 quality = user_settings.preferred_quality if user_settings else "best"
+                subtitle_langs = (user_settings.subtitle_langs or "") if user_settings else ""
                 from ..routers.downloads import _on_progress, _on_complete, _on_error
                 for yt_id, vid_id in new_video_ids:
                     existing_dl = db.query(Download).filter_by(
@@ -159,7 +160,7 @@ def _index_channel_task(channel_id: int, user_id: int):
                         import threading
                         t = threading.Thread(
                             target=ytdlp.start_download,
-                            args=(yt_id, dl.id, _on_progress, _on_complete, _on_error, quality),
+                            args=(yt_id, dl.id, _on_progress, _on_complete, _on_error, quality, subtitle_langs),
                             daemon=True,
                         )
                         t.start()

backend/routers/downloads.py

@@ -127,6 +127,7 @@ def create_download(
     user_settings = db.query(UserSettings).filter_by(user_id=current_user.id).first()
     default_quality = user_settings.preferred_quality if user_settings else "best"
     quality = body.quality if body.quality in ytdlp.QUALITY_FORMATS else default_quality
+    subtitle_langs = (user_settings.subtitle_langs or "") if user_settings else ""
 
     _DL_SELECT = """
         SELECT d.id, d.status, d.progress_percent, d.resolution,
@@ -155,7 +156,7 @@ def create_download(
         ytdlp.start_download,
         video.youtube_video_id, dl.id,
         _on_progress, _on_complete, _on_error,
-        quality,
+        quality, subtitle_langs,
     )
 
     row = db.execute(text(_DL_SELECT), {"id": dl.id}).mappings().first()
@@ -190,6 +191,11 @@ def _get_quality(db, user_id: int) -> str:
     return s.preferred_quality if s else "best"
 
 
+def _get_subtitle_langs(db, user_id: int) -> str:
+    s = db.query(UserSettings).filter_by(user_id=user_id).first()
+    return (s.subtitle_langs or "") if s else ""
+
+
 @router.post("/channel/{channel_id}", status_code=202)
 def download_channel_videos(
     channel_id: int,
@@ -198,6 +204,7 @@ def download_channel_videos(
     current_user: User = Depends(get_current_user),
 ):
     quality = _get_quality(db, current_user.id)
+    subtitle_langs = _get_subtitle_langs(db, current_user.id)
     rows = db.execute(
         text("""
             SELECT v.id, v.youtube_video_id
@@ -216,7 +223,7 @@ def download_channel_videos(
         db.flush()
         background_tasks.add_task(
             ytdlp.start_download, row["youtube_video_id"], dl.id,
-            _on_progress, _on_complete, _on_error, quality,
+            _on_progress, _on_complete, _on_error, quality, subtitle_langs,
         )
         count += 1
     db.commit()
@@ -230,6 +237,7 @@ def download_following_videos(
     current_user: User = Depends(get_current_user),
 ):
     quality = _get_quality(db, current_user.id)
+    subtitle_langs = _get_subtitle_langs(db, current_user.id)
     rows = db.execute(
         text("""
             SELECT v.id, v.youtube_video_id

backend/routers/settings.py

@@ -34,6 +34,8 @@ class SettingsOut(BaseModel):
     feed_weight_affinity: float = 5.0
     feed_weight_channel: float = 5.0
     use_oauth2: bool = False
+    sync_interval_hours: int = 0
+    subtitle_langs: str = ""
 
     model_config = {"from_attributes": True}
 
@@ -55,6 +57,8 @@ class SettingsPatch(BaseModel):
     feed_weight_affinity: Optional[float] = Field(None, ge=0.0, le=10.0)
     feed_weight_channel: Optional[float] = Field(None, ge=0.0, le=10.0)
     use_oauth2: Optional[bool] = None
+    sync_interval_hours: Optional[int] = Field(None, ge=0, le=168)
+    subtitle_langs: Optional[str] = None
 
 
 def _get_or_create(db: Session, user_id: int) -> UserSettings:
@@ -123,6 +127,10 @@ def update_settings(
     if body.use_oauth2 is not None:
         s.use_oauth2 = body.use_oauth2
         ytdlp.set_oauth2(body.use_oauth2)
+    if body.sync_interval_hours is not None:
+        s.sync_interval_hours = body.sync_interval_hours
+    if body.subtitle_langs is not None:
+        s.subtitle_langs = body.subtitle_langs.strip()
 
     db.commit()
     db.refresh(s)

backend/routers/stats.py

@@ -1,8 +1,12 @@
+import os
+import shutil
+
 from fastapi import APIRouter, Depends, HTTPException
 from sqlalchemy.orm import Session
 from sqlalchemy import text
 
 from ..auth_utils import get_current_user
+from ..config import settings
 from ..database import get_db
 from ..models import User, UserTagAffinity
 
@@ -120,6 +124,15 @@ def get_stats(
         {"uid": uid},
     ).mappings().first()
 
+    try:
+        disk = shutil.disk_usage(settings.download_path)
+        download_bytes = sum(
+            e.stat().st_size for e in os.scandir(settings.download_path) if e.is_file()
+        )
+    except Exception:
+        disk = None
+        download_bytes = 0
+
     return {
         "total_watched": totals["total_watched"] or 0,
         "total_watch_seconds": totals["total_watch_seconds"] or 0,
@@ -141,6 +154,12 @@ def get_stats(
         "total_liked": liked_count["n"] or 0,
         "top_categories": [dict(r) for r in top_categories],
         "taste_profile": [dict(r) for r in taste_profile],
+        "disk": {
+            "total_bytes": disk.total if disk else None,
+            "free_bytes": disk.free if disk else None,
+            "used_bytes": disk.used if disk else None,
+            "download_bytes": download_bytes,
+        },
     }
 
 

backend/services/ytdlp.py

@@ -621,17 +621,20 @@ def start_download(
     on_complete: Any,
     on_error: Any,
     quality: str = "best",
+    subtitle_langs: str = "",
 ) -> None:
     """Start yt-dlp download in a background thread.
 
-    Uses a single progressive MP4 format so the file is playable as it downloads.
     --no-part writes directly to the final filename (no .part rename at the end).
     """
     url = f"https://www.youtube.com/watch?v={video_id}"
-    # Predictable output path — lets the player start before download finishes
     output_template = str(Path(settings.download_path) / f"{video_id}.%(ext)s")
 
     fmt = QUALITY_FORMATS.get(quality, QUALITY_FORMATS["best"])
+    subtitle_args = (
+        ["--write-subs", "--write-auto-subs", "--sub-langs", subtitle_langs, "--convert-subs", "srt"]
+        if subtitle_langs else []
+    )
 
     def _run_download():
         with _SEMAPHORE:
@@ -645,6 +648,7 @@ def start_download(
                     "--no-part", "--no-mtime",
                     "-o", output_template,
                     "--newline", "--progress", "--no-colors",
+                    *subtitle_args,
                     *cookie_args,
                 ],
                 stdout=subprocess.PIPE,

frontend/src/pages/Settings.jsx

@@ -650,6 +650,25 @@ export default function SettingsPage() {
       <DiagnosticSection />
       <SubscriptionImportSection />
 
+      {/* Sync */}
+      <Section title="Sync">
+        <Row
+          label="Auto-sync interval"
+          hint="How often to automatically sync your followed channels in the background."
+        >
+          <select
+            value={s?.sync_interval_hours ?? 0}
+            onChange={(e) => set({ sync_interval_hours: Number(e.target.value) })}
+            className="bg-zinc-800 text-zinc-200 text-sm rounded-lg px-3 py-1.5 border border-zinc-700 focus:outline-none focus:border-accent"
+          >
+            <option value={0}>Off</option>
+            <option value={6}>Every 6 hours</option>
+            <option value={12}>Every 12 hours</option>
+            <option value={24}>Every 24 hours</option>
+          </select>
+        </Row>
+      </Section>
+
       {/* Download quality */}
       <Section title="Download quality">
         <Row
@@ -691,6 +710,18 @@ export default function SettingsPage() {
             onChange={(v) => set({ auto_download_on_sync: v })}
           />
         </Row>
+        <Row
+          label="Subtitle languages"
+          hint={'Download subtitles for these languages. e.g. "en" or "en,sv". Leave blank to skip.'}
+        >
+          <input
+            type="text"
+            value={s?.subtitle_langs ?? ""}
+            onChange={(e) => set({ subtitle_langs: e.target.value })}
+            placeholder="en, sv, …"
+            className="bg-zinc-800 text-zinc-200 text-sm rounded-lg px-3 py-1.5 border border-zinc-700 focus:outline-none focus:border-accent w-36"
+          />
+        </Row>
       </Section>
 
       {/* Feed */}

frontend/src/pages/Stats.jsx

@@ -11,6 +11,14 @@ function fmt(seconds) {
   return `${h}h ${m}m`;
 }
 
+function fmtBytes(bytes) {
+  if (!bytes) return "0 B";
+  const units = ["B", "KB", "MB", "GB", "TB"];
+  let i = 0, v = bytes;
+  while (v >= 1024 && i < units.length - 1) { v /= 1024; i++; }
+  return `${v.toFixed(i === 0 ? 0 : 1)} ${units[i]}`;
+}
+
 function StatCard({ label, value, sub }) {
   return (
     <div className="bg-zinc-900 rounded-2xl p-4 flex flex-col gap-1">
@@ -170,6 +178,29 @@ export default function Stats() {
         )}
       </div>
 
+      {/* Disk usage */}
+      {data.disk?.total_bytes && (
+        <div className="bg-zinc-900 rounded-2xl p-5 flex flex-col gap-3">
+          <h2 className="text-xs font-semibold text-zinc-500 uppercase tracking-wider">Disk usage</h2>
+          <div className="flex flex-col gap-2">
+            <div className="flex justify-between text-sm">
+              <span className="text-zinc-400">Downloads</span>
+              <span className="text-zinc-300 font-mono">{fmtBytes(data.disk.download_bytes)}</span>
+            </div>
+            <div className="h-2 bg-zinc-800 rounded-full overflow-hidden">
+              <div
+                className="h-full bg-accent/70 rounded-full transition-all"
+                style={{ width: `${Math.min((data.disk.used_bytes / data.disk.total_bytes) * 100, 100)}%` }}
+              />
+            </div>
+            <div className="flex justify-between text-[11px] text-zinc-600">
+              <span>{fmtBytes(data.disk.used_bytes)} used</span>
+              <span>{fmtBytes(data.disk.free_bytes)} free · {fmtBytes(data.disk.total_bytes)} total</span>
+            </div>
+          </div>
+        </div>
+      )}
+
       {/* Taste profile */}
       {topTags.length > 0 && (
         <div className="bg-zinc-900 rounded-2xl p-5 flex flex-col gap-3">