-- Migration 128: Pool configuration table
-- Controls whether workers can claim tasks from the pool

CREATE TABLE IF NOT EXISTS pool_config (
  id SERIAL PRIMARY KEY,
  pool_open BOOLEAN NOT NULL DEFAULT true,
  closed_reason TEXT,
  closed_at TIMESTAMPTZ,
  closed_by VARCHAR(100),
  opened_at TIMESTAMPTZ DEFAULT NOW(),
  created_at TIMESTAMPTZ DEFAULT NOW(),
  updated_at TIMESTAMPTZ DEFAULT NOW()
);

-- Insert default config (pool open)
INSERT INTO pool_config (pool_open, opened_at)
VALUES (true, NOW())
ON CONFLICT DO NOTHING;

-- Update claim_task function to check pool status
CREATE OR REPLACE FUNCTION claim_task(
  p_role VARCHAR(50),
  p_worker_id VARCHAR(100),
  p_curl_passed BOOLEAN DEFAULT TRUE,
  p_http_passed BOOLEAN DEFAULT FALSE
) RETURNS worker_tasks AS $$
DECLARE
  claimed_task worker_tasks;
  worker_state VARCHAR(2);
  session_valid BOOLEAN;
  session_tasks INT;
  max_tasks INT;
  is_pool_open BOOLEAN;
BEGIN
  -- Check if pool is open
  SELECT pool_open INTO is_pool_open FROM pool_config LIMIT 1;
  IF NOT COALESCE(is_pool_open, true) THEN
    RETURN NULL;  -- Pool is closed, no claiming allowed
  END IF;

  -- Get worker's current geo session info
  SELECT
    current_state,
    session_task_count,
    session_max_tasks,
    (geo_session_started_at IS NOT NULL AND geo_session_started_at > NOW() - INTERVAL '60 minutes')
  INTO worker_state, session_tasks, max_tasks, session_valid
  FROM worker_registry
  WHERE worker_id = p_worker_id;

  -- Check if worker has reached max concurrent tasks (default 5)
  IF session_tasks >= COALESCE(max_tasks, 5) THEN
    RETURN NULL;
  END IF;

  -- If no valid geo session, or session expired, worker can't claim tasks
  -- Worker must re-qualify first
  IF worker_state IS NULL OR NOT session_valid THEN
    RETURN NULL;
  END IF;

  -- Claim task matching worker's state
  UPDATE worker_tasks
  SET
    status = 'claimed',
    worker_id = p_worker_id,
    claimed_at = NOW(),
    updated_at = NOW()
  WHERE id = (
    SELECT wt.id FROM worker_tasks wt
    JOIN dispensaries d ON wt.dispensary_id = d.id
    WHERE wt.role = p_role
      AND wt.status = 'pending'
      AND (wt.scheduled_for IS NULL OR wt.scheduled_for <= NOW())
      -- GEO FILTER: Task's dispensary must match worker's state
      AND d.state = worker_state
      -- Method compatibility: worker must have passed the required preflight
      AND (
        wt.method IS NULL  -- No preference, any worker can claim
        OR (wt.method = 'curl' AND p_curl_passed = TRUE)
        OR (wt.method = 'http' AND p_http_passed = TRUE)
      )
      -- Exclude stores that already have an active task
      AND (wt.dispensary_id IS NULL OR wt.dispensary_id NOT IN (
        SELECT dispensary_id FROM worker_tasks
        WHERE status IN ('claimed', 'running')
        AND dispensary_id IS NOT NULL
        AND dispensary_id != wt.dispensary_id
      ))
    ORDER BY wt.priority DESC, wt.created_at ASC
    LIMIT 1
    FOR UPDATE SKIP LOCKED
  )
  RETURNING * INTO claimed_task;

  -- INCREMENT session_task_count if we claimed a task
  IF claimed_task.id IS NOT NULL THEN
    UPDATE worker_registry
    SET session_task_count = session_task_count + 1
    WHERE worker_id = p_worker_id;
  END IF;

  RETURN claimed_task;
END;
$$ LANGUAGE plpgsql;

-- Verify
SELECT 'pool_config table created' as status;
SELECT * FROM pool_config;