-- Migration 079: Task Schedules for Database-Driven Scheduler
-- Per TASK_WORKFLOW_2024-12-10.md: Replaces node-cron with DB-driven scheduling
--
-- 2024-12-10: Created for reliable, multi-replica-safe task scheduling

-- task_schedules: Stores schedule definitions and state
CREATE TABLE IF NOT EXISTS task_schedules (
  id SERIAL PRIMARY KEY,
  name VARCHAR(100) NOT NULL UNIQUE,
  role VARCHAR(50) NOT NULL,  -- TaskRole: product_refresh, store_discovery, etc.
  description TEXT,

  -- Schedule configuration
  enabled BOOLEAN DEFAULT TRUE,
  interval_hours INTEGER NOT NULL DEFAULT 4,
  priority INTEGER DEFAULT 0,

  -- Optional scope filters
  state_code VARCHAR(2),  -- NULL = all states
  platform VARCHAR(50),   -- NULL = all platforms

  -- Execution state (updated by scheduler)
  last_run_at TIMESTAMPTZ,
  next_run_at TIMESTAMPTZ,
  last_task_count INTEGER DEFAULT 0,
  last_error TEXT,

  created_at TIMESTAMPTZ DEFAULT NOW(),
  updated_at TIMESTAMPTZ DEFAULT NOW()
);

-- Indexes for scheduler queries
CREATE INDEX IF NOT EXISTS idx_task_schedules_enabled ON task_schedules(enabled) WHERE enabled = TRUE;
CREATE INDEX IF NOT EXISTS idx_task_schedules_next_run ON task_schedules(next_run_at) WHERE enabled = TRUE;

-- Insert default schedules
INSERT INTO task_schedules (name, role, interval_hours, priority, description, next_run_at)
VALUES
  ('product_refresh_all', 'product_refresh', 4, 0, 'Generate product refresh tasks for all crawl-enabled stores every 4 hours', NOW()),
  ('store_discovery_dutchie', 'store_discovery', 24, 5, 'Discover new Dutchie stores daily', NOW()),
  ('analytics_refresh', 'analytics_refresh', 6, 0, 'Refresh analytics materialized views every 6 hours', NOW())
ON CONFLICT (name) DO NOTHING;

-- Comment for documentation
COMMENT ON TABLE task_schedules IS 'Database-driven task scheduler configuration. Per TASK_WORKFLOW_2024-12-10.md:
- Schedules persist in DB (survive restarts)
- Uses SELECT FOR UPDATE SKIP LOCKED for multi-replica safety
- Scheduler polls every 60s and executes due schedules
- Creates tasks in worker_tasks for task-worker.ts to process';