WIP: Move rows within and between playlists working

app/repository.py

@@ -316,43 +316,55 @@ def move_rows_to_playlist(
     Move rows between playlists.
     """
 
-    with db.Session() as session:
+    log.debug(
-        # Prepare desination playlist
+        f"move_rows_to_playlist({from_rows=}, {from_playlist_id=}, {to_row=}, {to_playlist_id=})"
-        # Find last used row
-        last_row = session.execute(
-            select(func.max(PlaylistRows.row_number)).where(
-                PlaylistRows.playlist_id == to_playlist_id
     )
-        ).scalar_one()
+
-        if last_row is None:
+    with db.Session() as session:
-            last_row = -1
+        # Sanity check row numbers
-        # Make room in destination
+        _check_playlist_integrity(session, from_playlist_id, fix=False)
-        if to_row <= last_row:
+        _check_playlist_integrity(session, to_playlist_id, fix=False)
-            _move_rows(session, to_playlist_id, to_row, len(from_rows))
+
-        # Move rows
+        # Check there are no playlist rows with playlist_id == PENDING_MOVE
-        row_offset = to_row - min(from_rows)
+        pending_move_rows = get_playlist_rows(Config.PLAYLIST_PENDING_MOVE)
-        stmt = (
+        if pending_move_rows:
+            raise ApplicationError(f"move_rows_to_playlist: {pending_move_rows=}")
+
+        # Put rows to be moved into PENDING_MOVE playlist
+        session.execute(
             update(PlaylistRows)
             .where(
                 PlaylistRows.playlist_id == from_playlist_id,
                 PlaylistRows.row_number.in_(from_rows),
             )
-            .values(
+            .values(playlist_id=Config.PLAYLIST_PENDING_MOVE)
-                playlist_id=to_playlist_id,
-                row_number=PlaylistRows.row_number + row_offset,
         )
-        )
-        session.execute(stmt)
-        # Remove gaps in source
-        _move_rows(
-            session=session,
-            playlist_id=from_playlist_id,
-            starting_row=max(from_rows) + 1,
-            move_by=(len(from_rows) * -1),
-        )
-        # Commit changes
         session.commit()
-        # Sanity check
+
+        # Resequence remaining row numbers
+        _check_playlist_integrity(session, from_playlist_id, fix=True)
+
+        # Make space for moved rows.
+        _move_rows(session, to_playlist_id, to_row, len(from_rows))
+
+        # Move the PENDING_MOVE rows back and fixup row numbers
+        update_list: list[dict[str, int]] = []
+        next_row = to_row
+        # PLAYLIST_PENDING_MOVE may have gaps so don't check it
+        for row_to_move in get_playlist_rows(
+            Config.PLAYLIST_PENDING_MOVE, check_playlist_itegrity=False
+        ):
+            update_list.append(
+                {"id": row_to_move.playlistrow_id, "row_number": next_row}
+            )
+            update_list.append(
+                {"id": row_to_move.playlistrow_id, "playlist_id": to_playlist_id}
+            )
+            next_row += 1
+        session.execute(update(PlaylistRows), update_list)
+        session.commit()
+
+        # Sanity check row numbers
     _check_playlist_integrity(session, from_playlist_id, fix=False)
     _check_playlist_integrity(session, to_playlist_id, fix=False)
 
@@ -416,9 +428,16 @@ def move_rows_within_playlist(
         # Move the PENDING_MOVE rows back and fixup row numbers
         update_list: list[dict[str, int]] = []
         next_row = space_row
-        for row_to_move in get_playlist_rows(Config.PLAYLIST_PENDING_MOVE):
+        # PLAYLIST_PENDING_MOVE may have gaps so don't check it
-            update_list.append({"id": row_to_move.playlistrow_id, "row_number": next_row})
+        for row_to_move in get_playlist_rows(
-            update_list.append({"id": row_to_move.playlistrow_id, "playlist_id": playlist_id})
+            Config.PLAYLIST_PENDING_MOVE, check_playlist_itegrity=False
+        ):
+            update_list.append(
+                {"id": row_to_move.playlistrow_id, "row_number": next_row}
+            )
+            update_list.append(
+                {"id": row_to_move.playlistrow_id, "playlist_id": playlist_id}
+            )
             next_row += 1
         session.execute(update(PlaylistRows), update_list)
         session.commit()
@@ -554,7 +573,9 @@ def get_playlist_row(playlistrow_id: int) -> PlaylistRowDTO | None:
     return dto
 
 
-def get_playlist_rows(playlist_id: int) -> list[PlaylistRowDTO]:
+def get_playlist_rows(
+    playlist_id: int, check_playlist_itegrity=True
+) -> list[PlaylistRowDTO]:
     # Alias PlaydatesTable for subquery
     LatestPlaydate = aliased(Playdates)
 
@@ -597,7 +618,10 @@ def get_playlist_rows(playlist_id: int) -> list[PlaylistRowDTO]:
         results = session.execute(stmt).all()
         # Sanity check
         # TODO: would be good to be confident at removing this
-        _check_playlist_integrity(session=session, playlist_rows=results, fix=False)
+        if check_playlist_itegrity:
+            _check_playlist_integrity(
+                session=session, playlist_id=playlist_id, fix=False
+            )
 
         dto_list = []
         for row in results:

tests/test_repository.py

@@ -241,3 +241,34 @@ class MyTestCase(unittest.TestCase):
         for row in repository.get_playlist_rows(playlist.playlist_id):
             new_order.append(int(row.note))
         assert new_order == [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+
+    def test_move_rows_to_playlist(self):
+        number_of_rows = 11
+        rows_to_move = [2, 4, 6]
+        to_row = 5
+
+        (playlist_src, model_src) = self.create_rows("src playlist", number_of_rows)
+        (playlist_dst, model_dst) = self.create_rows("dst playlist", number_of_rows)
+
+        repository.move_rows_to_playlist(
+            rows_to_move, playlist_src.playlist_id, to_row, playlist_dst.playlist_id
+        )
+
+        # Check we have all rows and plr_rownums are correct
+        new_order_src = []
+        for row in repository.get_playlist_rows(playlist_src.playlist_id):
+            new_order_src.append(int(row.note))
+        assert new_order_src == [0, 1, 3, 5, 7, 8, 9, 10]
+        new_order_dst = []
+        for row in repository.get_playlist_rows(playlist_dst.playlist_id):
+            new_order_dst.append(int(row.note))
+        assert new_order_dst == [0, 1, 2, 3, 4, 2, 4, 6, 5, 6, 7, 8, 9, 10]
+
+    def test_remove_rows(self):
+        pass
+
+    def test_get_playlist_by_id(self):
+        pass
+
+    def test_settings(self):
+        pass