-- Workers table for worker pool registration and health tracking.
-- Workers register on startup, send heartbeats, and are marked offline
-- if they miss heartbeats beyond the configured threshold.

CREATE TABLE IF NOT EXISTS workers (
    id              VARCHAR(255) PRIMARY KEY,
    hostname        VARCHAR(255) NOT NULL,
    status          VARCHAR(50) NOT NULL DEFAULT 'idle',
    current_task    VARCHAR(255),
    capabilities    JSONB DEFAULT '[]',
    version         VARCHAR(50),
    registered_at   TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    last_heartbeat  TIMESTAMPTZ NOT NULL DEFAULT NOW(),

    CONSTRAINT workers_valid_status CHECK (status IN ('idle', 'busy', 'draining', 'offline'))
);

-- Index for finding idle workers (used during task assignment)
CREATE INDEX IF NOT EXISTS idx_workers_status
    ON workers(status)
    WHERE status = 'idle';

-- Index for health checker (finding stale heartbeats)
CREATE INDEX IF NOT EXISTS idx_workers_heartbeat
    ON workers(last_heartbeat);

COMMENT ON TABLE workers IS 'Worker pool registry for tracking worker lifecycle and health';
COMMENT ON COLUMN workers.id IS 'Unique worker identifier (typically Kubernetes pod name)';
COMMENT ON COLUMN workers.hostname IS 'Worker hostname for identification';
COMMENT ON COLUMN workers.status IS 'Worker status: idle, busy, draining, offline';
COMMENT ON COLUMN workers.current_task IS 'ID of the work queue task currently being executed';
COMMENT ON COLUMN workers.capabilities IS 'JSON array of worker capabilities (e.g., build, deploy)';
COMMENT ON COLUMN workers.version IS 'Worker binary version string';
COMMENT ON COLUMN workers.last_heartbeat IS 'Most recent heartbeat timestamp for health monitoring';

-- Build audit table for tracking build execution history.
-- Every build request creates an audit entry that is updated
-- when the build completes or fails.

CREATE TABLE IF NOT EXISTS build_audit (
    task_id         VARCHAR(255) PRIMARY KEY,
    project_id      VARCHAR(255) NOT NULL,
    worker_id       VARCHAR(255),
    spec            JSONB NOT NULL,
    result          JSONB,
    status          VARCHAR(50) NOT NULL DEFAULT 'pending',
    started_at      TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    completed_at    TIMESTAMPTZ,

    CONSTRAINT build_audit_valid_status CHECK (status IN ('pending', 'running', 'completed', 'failed', 'cancelled'))
);

-- Index for project build history queries
CREATE INDEX IF NOT EXISTS idx_build_audit_project
    ON build_audit(project_id);

-- Index for status-based queries (e.g., "show all running builds")
CREATE INDEX IF NOT EXISTS idx_build_audit_status
    ON build_audit(status);

-- Index for time-ordered queries (most recent first)
CREATE INDEX IF NOT EXISTS idx_build_audit_started
    ON build_audit(started_at DESC);

COMMENT ON TABLE build_audit IS 'Audit trail for build executions with full spec and result history';
COMMENT ON COLUMN build_audit.task_id IS 'Work queue task ID (links to work_queue.id)';
COMMENT ON COLUMN build_audit.project_id IS 'Project this build belongs to';
COMMENT ON COLUMN build_audit.worker_id IS 'Worker that executed the build';
COMMENT ON COLUMN build_audit.spec IS 'JSON build specification (prompt, template, variables, etc.)';
COMMENT ON COLUMN build_audit.result IS 'JSON build result (output, commit_sha, files_changed, etc.)';
COMMENT ON COLUMN build_audit.status IS 'Build status: pending, running, completed, failed, cancelled';