-- +goose Up
CREATE TABLE playlist_groups (
    id SERIAL PRIMARY KEY,
    playlist_id INTEGER NOT NULL REFERENCES playlists(id) ON DELETE CASCADE,
    name VARCHAR(255) NOT NULL CHECK (length(trim(name)) > 0),
    position INTEGER NOT NULL CHECK (position >= 0),
    end_mode TEXT NOT NULL DEFAULT 'repeat' CHECK (end_mode IN ('repeat', 'stop', 'next')),
    UNIQUE (playlist_id, id)
);
ALTER TABLE playlist_tracks ADD COLUMN group_id INTEGER;
ALTER TABLE playlist_tracks ADD CONSTRAINT playlist_tracks_group_fk
    FOREIGN KEY (playlist_id, group_id) REFERENCES playlist_groups(playlist_id, id);
ALTER TABLE game_music_states ADD COLUMN group_id INTEGER;
ALTER TABLE game_music_states ADD CONSTRAINT game_music_states_group_fk
    FOREIGN KEY (playlist_id, group_id) REFERENCES playlist_groups(playlist_id, id);

-- +goose Down
ALTER TABLE game_music_states DROP COLUMN group_id;
ALTER TABLE playlist_tracks DROP COLUMN group_id;
DROP TABLE playlist_groups;