Update app

app/routes/api.py

@@ -6,12 +6,12 @@ import time
 from flask import Blueprint, Response, abort, jsonify, request, stream_with_context, url_for
 
 from ..extensions import db
-from ..models import Display, DisplaySession
+from ..models import Display, DisplayPlaylist, DisplaySession, Playlist, PlaylistItem
 
 bp = Blueprint("api", __name__, url_prefix="/api")
 
 
-MAX_ACTIVE_SESSIONS_PER_DISPLAY = 2
+MAX_ACTIVE_SESSIONS_PER_DISPLAY = 3
 SESSION_TTL_SECONDS = 90
 
 
@@ -84,16 +84,49 @@ def _playlist_signature(display: Display) -> tuple[int | None, str]:
     duration changes, and item adds/deletes trigger an update.
     """
 
-    playlist = display.assigned_playlist
-    if not playlist:
+    # Determine active playlists. If display_playlist has any rows, use those.
+    # Otherwise fall back to the legacy assigned_playlist_id.
+    mapped_ids = [
+        r[0]
+        for r in db.session.query(DisplayPlaylist.playlist_id)
+        .filter(DisplayPlaylist.display_id == display.id)
+        .order_by(DisplayPlaylist.position.asc(), DisplayPlaylist.playlist_id.asc())
+        .all()
+    ]
+    use_mapping = bool(mapped_ids)
+    active_ids = mapped_ids
+    if not active_ids and display.assigned_playlist_id:
+        active_ids = [display.assigned_playlist_id]
+        use_mapping = False
+
+    if not active_ids:
         raw = "no-playlist"
         return None, hashlib.sha1(raw.encode("utf-8")).hexdigest()
 
+    # Pull items in a stable order so reordering affects signature.
+    if use_mapping:
+        items = (
+            PlaylistItem.query.join(DisplayPlaylist, DisplayPlaylist.playlist_id == PlaylistItem.playlist_id)
+            .filter(
+                DisplayPlaylist.display_id == display.id,
+                PlaylistItem.playlist_id.in_(active_ids),
+            )
+            .order_by(DisplayPlaylist.position.asc(), PlaylistItem.position.asc())
+            .all()
+        )
+    else:
+        items = (
+            PlaylistItem.query.filter(PlaylistItem.playlist_id == active_ids[0])
+            .order_by(PlaylistItem.position.asc())
+            .all()
+        )
+
     payload = {
-        "playlist_id": playlist.id,
+        "playlist_ids": list(active_ids),
         "items": [
             {
                 "id": it.id,
+                "playlist_id": it.playlist_id,
                 "pos": it.position,
                 "type": it.item_type,
                 "title": it.title,
@@ -101,11 +134,15 @@ def _playlist_signature(display: Display) -> tuple[int | None, str]:
                 "file_path": it.file_path,
                 "url": it.url,
             }
-            for it in playlist.items
+            for it in items
         ],
     }
     raw = json.dumps(payload, sort_keys=True, separators=(",", ":"))
-    return playlist.id, hashlib.sha1(raw.encode("utf-8")).hexdigest()
+    # signature returns a single playlist_id previously; now return None when multiple.
+    # callers only use it for changed-detection.
+    if len(set(active_ids)) == 1:
+        return active_ids[0], hashlib.sha1(raw.encode("utf-8")).hexdigest()
+    return None, hashlib.sha1(raw.encode("utf-8")).hexdigest()
 
 
 @bp.get("/display/<token>/playlist")
@@ -114,21 +151,59 @@ def display_playlist(token: str):
     if not display:
         abort(404)
 
-    # Enforce: a display URL/token can be opened by max 2 concurrently active sessions.
+    # Enforce: a display URL/token can be opened by max 3 concurrently active sessions.
     # Player sends a stable `sid` via querystring.
     sid = request.args.get("sid")
     ok, resp = _enforce_and_touch_display_session(display, sid)
     if not ok:
         return resp
 
-    playlist = display.assigned_playlist
-    if not playlist:
-        return jsonify({"display": display.name, "playlist": None, "items": []})
+    # Determine active playlists. If display_playlist has any rows, use those.
+    # Otherwise fall back to the legacy assigned_playlist_id.
+    mapped_ids = [
+        r[0]
+        for r in db.session.query(DisplayPlaylist.playlist_id)
+        .filter(DisplayPlaylist.display_id == display.id)
+        .order_by(DisplayPlaylist.position.asc(), DisplayPlaylist.playlist_id.asc())
+        .all()
+    ]
+    use_mapping = bool(mapped_ids)
+    active_ids = mapped_ids
+    if not active_ids and display.assigned_playlist_id:
+        active_ids = [display.assigned_playlist_id]
+        use_mapping = False
+
+    if not active_ids:
+        return jsonify({"display": display.name, "playlists": [], "items": []})
+
+    playlists = Playlist.query.filter(Playlist.id.in_(active_ids)).all()
+    pl_by_id = {p.id: p for p in playlists}
+    ordered_playlists = [pl_by_id[x] for x in active_ids if x in pl_by_id]
+
+    # Merge items across active playlists.
+    if use_mapping:
+        merged = (
+            PlaylistItem.query.join(DisplayPlaylist, DisplayPlaylist.playlist_id == PlaylistItem.playlist_id)
+            .filter(
+                DisplayPlaylist.display_id == display.id,
+                PlaylistItem.playlist_id.in_(active_ids),
+            )
+            .order_by(DisplayPlaylist.position.asc(), PlaylistItem.position.asc())
+            .all()
+        )
+    else:
+        merged = (
+            PlaylistItem.query.filter(PlaylistItem.playlist_id == active_ids[0])
+            .order_by(PlaylistItem.position.asc())
+            .all()
+        )
 
     items = []
-    for item in playlist.items:
+    for item in merged:
         payload = {
             "id": item.id,
+            "playlist_id": item.playlist_id,
+            "playlist_name": (pl_by_id.get(item.playlist_id).name if pl_by_id.get(item.playlist_id) else None),
             "type": item.item_type,
             "title": item.title,
             "duration": item.duration_seconds,
@@ -142,7 +217,7 @@ def display_playlist(token: str):
     return jsonify(
         {
             "display": display.name,
-            "playlist": {"id": playlist.id, "name": playlist.name},
+            "playlists": [{"id": p.id, "name": p.name} for p in ordered_playlists],
             "items": items,
         }
     )