Added the playlist editor

src/queries/playlists.rs

@@ -103,3 +103,76 @@ pub async fn delete(db: &DatabaseConnection, id: i32) -> DbResult<()> {
     Playlists::delete_by_id(id).exec(db).await?;
     Ok(())
 }
+
+pub async fn add_track(db: &DatabaseConnection, playlist_id: i32, track_id: i32) -> DbResult<()> {
+    // Get max position for this playlist
+    let max_pos = PlaylistTracks::find()
+        .filter(playlist_track::Column::PlaylistId.eq(playlist_id))
+        .order_by_desc(playlist_track::Column::Position)
+        .one(db)
+        .await?
+        .map(|pt| pt.position)
+        .unwrap_or(-1);
+
+    let pt = TrackActiveModel {
+        playlist_id: Set(playlist_id),
+        track_id: Set(track_id),
+        position: Set(max_pos + 1),
+        ..Default::default()
+    };
+    pt.insert(db).await?;
+    Ok(())
+}
+
+pub async fn remove_track(
+    db: &DatabaseConnection,
+    playlist_id: i32,
+    track_id: i32,
+) -> DbResult<()> {
+    // Delete the playlist_track row
+    PlaylistTracks::delete_many()
+        .filter(playlist_track::Column::PlaylistId.eq(playlist_id))
+        .filter(playlist_track::Column::TrackId.eq(track_id))
+        .exec(db)
+        .await?;
+
+    // Renumber remaining positions
+    let remaining = PlaylistTracks::find()
+        .filter(playlist_track::Column::PlaylistId.eq(playlist_id))
+        .order_by_asc(playlist_track::Column::Position)
+        .all(db)
+        .await?;
+
+    for (i, pt) in remaining.into_iter().enumerate() {
+        let mut active: TrackActiveModel = pt.into();
+        active.position = Set(i as i32);
+        active.update(db).await?;
+    }
+
+    Ok(())
+}
+
+pub async fn reorder_tracks(
+    db: &DatabaseConnection,
+    playlist_id: i32,
+    track_ids: Vec<i32>,
+) -> DbResult<()> {
+    // Delete all playlist_tracks for this playlist
+    PlaylistTracks::delete_many()
+        .filter(playlist_track::Column::PlaylistId.eq(playlist_id))
+        .exec(db)
+        .await?;
+
+    // Re-insert with positions matching the vec order
+    for (pos, track_id) in track_ids.iter().enumerate() {
+        let pt = TrackActiveModel {
+            playlist_id: Set(playlist_id),
+            track_id: Set(*track_id),
+            position: Set(pos as i32),
+            ..Default::default()
+        };
+        pt.insert(db).await?;
+    }
+
+    Ok(())
+}