CREATE TABLE workflow_runs (
    id              UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    album_id        UUID NOT NULL REFERENCES albums(id) ON DELETE CASCADE,
    quality         VARCHAR(20) NOT NULL,
    status          VARCHAR(20) NOT NULL DEFAULT 'running',
    error_message   TEXT,
    started_at      TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    completed_at    TIMESTAMPTZ,
    created_at      TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at      TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    running_lock    BOOLEAN GENERATED ALWAYS AS (CASE WHEN status = 'running' THEN TRUE ELSE NULL END) STORED,
    CONSTRAINT idx_workflow_runs_active UNIQUE (album_id, quality, running_lock)
);

CREATE INDEX idx_workflow_runs_status ON workflow_runs(status);

CREATE TABLE album_events (
    id              UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    seq             BIGSERIAL NOT NULL,
    workflow_run_id UUID NOT NULL REFERENCES workflow_runs(id) ON DELETE CASCADE,
    album_id        UUID NOT NULL,
    event_type      VARCHAR(20) NOT NULL,
    step            VARCHAR(50) NOT NULL,
    message         TEXT NOT NULL,
    data_json       JSONB,
    created_at      TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE INDEX idx_album_events_workflow ON album_events(workflow_run_id);
CREATE INDEX idx_album_events_album ON album_events(album_id);
CREATE INDEX idx_album_events_seq ON album_events(seq);

ALTER TYPE download_state ADD VALUE IF NOT EXISTS 'cancelled';