-- Add migration script here
CREATE TABLE sessions (
    id SERIAL PRIMARY KEY,
    user_id INTEGER NOT NULL REFERENCES users(id),
    token TEXT NOT NULL UNIQUE,
    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
    expires_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP + INTERVAL '7 days'
);

CREATE OR REPLACE FUNCTION cleanup_expired_sessions()
RETURNS TRIGGER AS $$
BEGIN
  DELETE FROM sessions WHERE expires_at < NOW();
  RETURN NULL;
END;
$$ LANGUAGE plpgsql;

CREATE TRIGGER trigger_cleanup_sessions
    AFTER INSERT ON sessions
    EXECUTE FUNCTION cleanup_expired_sessions();