CREATE TABLE theme_schedules (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    theme_id UUID NOT NULL UNIQUE REFERENCES themes(id) ON DELETE CASCADE,
    user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    enabled BOOLEAN NOT NULL DEFAULT true,
    days JSONB NOT NULL DEFAULT '[]',
    time_utc TEXT NOT NULL DEFAULT '08:00',
    emails JSONB NOT NULL DEFAULT '[]',
    last_run_at TIMESTAMPTZ,
    created_at TIMESTAMPTZ NOT NULL DEFAULT now(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT now()
);
CREATE INDEX idx_theme_schedules_enabled ON theme_schedules(enabled) WHERE enabled = true;