-- ============================================================================
-- Payment Trigger Architecture
-- ============================================================================
-- This refactors the payment flow to use database triggers instead of
-- handling everything in the webhook function.
--
-- Flow:
-- 1. pakasir-webhook or admin updates order.payment_status = 'paid'
-- 2. Trigger fires -> calls handle_paid_order() function
-- 3. handle_paid_order() calls handle-order-paid edge function
-- 4. Edge function handles: access grants, notifications, meet links
-- ============================================================================

-- Enable pg_net extension for HTTP calls from PostgreSQL
CREATE EXTENSION IF NOT EXISTS pg_net;

-- ============================================================================
-- Function: handle_paid_order
-- Purpose: Called by trigger when order payment_status becomes 'paid'
-- Calls the edge function to handle all post-payment actions
-- ============================================================================
CREATE OR REPLACE FUNCTION handle_paid_order()
RETURNS TRIGGER AS $$
DECLARE
  edge_function_url TEXT;
  edge_function_response TEXT;
  order_data JSON;
BEGIN
  -- Only proceed if payment_status changed to 'paid'
  IF (NEW.payment_status != 'paid' OR OLD.payment_status = 'paid') THEN
    RETURN NEW;
  END IF;

  -- Log the payment event
  RAISE NOTICE 'Order % payment status changed to paid', NEW.id;

  -- Get the edge function URL from environment
  edge_function_url := current_setting('app.base_url', true) || '/functions/v1/handle-order-paid';

  -- Prepare order data
  order_data := json_build_object(
    'order_id', NEW.id,
    'user_id', NEW.user_id,
    'total_amount', NEW.total_amount,
    'payment_method', NEW.payment_method,
    'payment_provider', NEW.payment_provider
  );

  -- Call the edge function asynchronously via pg_net
  -- We use pg_net to avoid blocking the transaction
  PERFORM net.http_post(
    url := edge_function_url,
    headers := json_build_object(
      'Content-Type', 'application/json',
      'Authorization', 'Bearer ' || current_setting('app.service_role_key', true)
    ),
    body := order_data
  );

  RAISE NOTICE 'Called handle-order-paid for order %', NEW.id;

  RETURN NEW;
EXCEPTION
  WHEN OTHERS THEN
    -- Log error but don't fail the transaction
    RAISE WARNING 'Failed to call handle-order-paid for order %: %', NEW.id, SQLERRM;
    RETURN NEW;
END;
$$ LANGUAGE plpgsql;

-- ============================================================================
-- Trigger: on_order_paid
-- Purpose: Fires handle_paid_order() when order payment status changes
-- ============================================================================
DROP TRIGGER IF EXISTS on_order_paid ON orders;

CREATE TRIGGER on_order_paid
  AFTER UPDATE ON orders
  FOR EACH ROW
  WHEN (NEW.payment_status = 'paid' AND OLD.payment_status IS DISTINCT FROM NEW.payment_status)
  EXECUTE FUNCTION handle_paid_order();

-- ============================================================================
-- Comments for documentation
-- ============================================================================
COMMENT ON FUNCTION handle_paid_order() IS 'Triggered when order payment_status becomes "paid". Calls handle-order-paid edge function to handle access grants, notifications, and Meet link creation.';
COMMENT ON TRIGGER on_order_paid ON orders IS 'Fires handle_paid_order() function when payment status changes to paid';

-- ============================================================================
-- Grant necessary permissions
-- ============================================================================
GRANT EXECUTE ON FUNCTION handle_paid_order() TO postgres;
GRANT USAGE ON SCHEMA net TO postgres;