CREATE OR REPLACE FUNCTION public.log_order_group_change()
RETURNS trigger
LANGUAGE plpgsql
SECURITY DEFINER
SET search_path TO 'public'
AS $$
DECLARE
  v_user_id uuid;
  v_changes jsonb := '{}'::jsonb;
  v_action text;
  v_source text;
BEGIN
  -- Determine who made the change
  v_user_id := auth.uid();
  v_source := CASE WHEN v_user_id IS NOT NULL THEN 'user' ELSE 'system' END;

  -- Track only meaningful field changes
  IF NEW.notification_status IS DISTINCT FROM OLD.notification_status THEN
    v_changes := v_changes || jsonb_build_object(
      'notification_status',
      jsonb_build_object('old', OLD.notification_status, 'new', NEW.notification_status)
    );
  END IF;

  IF NEW.delivery_status IS DISTINCT FROM OLD.delivery_status THEN
    v_changes := v_changes || jsonb_build_object(
      'delivery_status',
      jsonb_build_object('old', OLD.delivery_status, 'new', NEW.delivery_status)
    );
  END IF;

  IF NEW.status IS DISTINCT FROM OLD.status THEN
    v_changes := v_changes || jsonb_build_object(
      'status',
      jsonb_build_object('old', OLD.status, 'new', NEW.status)
    );
  END IF;

  IF NEW.assigned_driver_id IS DISTINCT FROM OLD.assigned_driver_id THEN
    v_changes := v_changes || jsonb_build_object(
      'assigned_driver_id',
      jsonb_build_object('old', OLD.assigned_driver_id, 'new', NEW.assigned_driver_id)
    );
  END IF;

  IF NEW.delivery_link IS DISTINCT FROM OLD.delivery_link THEN
    v_changes := v_changes || jsonb_build_object(
      'delivery_link',
      jsonb_build_object('old', OLD.delivery_link, 'new', NEW.delivery_link)
    );
  END IF;

  IF NEW.first_sms_sent_at IS DISTINCT FROM OLD.first_sms_sent_at THEN
    v_changes := v_changes || jsonb_build_object(
      'first_sms_sent_at',
      jsonb_build_object('old', OLD.first_sms_sent_at, 'new', NEW.first_sms_sent_at)
    );
  END IF;

  IF NEW.second_sms_sent_at IS DISTINCT FROM OLD.second_sms_sent_at THEN
    v_changes := v_changes || jsonb_build_object(
      'second_sms_sent_at',
      jsonb_build_object('old', OLD.second_sms_sent_at, 'new', NEW.second_sms_sent_at)
    );
  END IF;

  IF NEW.last_sms_error IS DISTINCT FROM OLD.last_sms_error THEN
    v_changes := v_changes || jsonb_build_object(
      'last_sms_error',
      jsonb_build_object('old', OLD.last_sms_error, 'new', NEW.last_sms_error)
    );
  END IF;

  -- Only insert if something meaningful changed
  IF v_changes = '{}'::jsonb THEN
    RETURN NEW;
  END IF;

  -- Determine action label
  v_action := CASE
    WHEN NEW.delivery_status IS DISTINCT FROM OLD.delivery_status THEN 'delivery_status_change'
    WHEN NEW.notification_status IS DISTINCT FROM OLD.notification_status THEN 'notification_status_change'
    WHEN NEW.assigned_driver_id IS DISTINCT FROM OLD.assigned_driver_id THEN 'driver_assignment_change'
    WHEN NEW.delivery_link IS DISTINCT FROM OLD.delivery_link THEN 'delivery_link_change'
    ELSE 'field_change'
  END;

  INSERT INTO order_history (order_group_id, action, old_status, new_status, user_id, metadata)
  VALUES (
    NEW.id,
    v_action,
    OLD.delivery_status,
    NEW.delivery_status,
    v_user_id,
    jsonb_build_object('changes', v_changes, 'source', v_source, 'group_key', NEW.group_key)
  );

  RETURN NEW;
END;
$$;

-- Drop old trigger if exists
DROP TRIGGER IF EXISTS log_order_group_change_trigger ON public.order_groups;

-- Create trigger AFTER UPDATE (only when fields actually change)
CREATE TRIGGER log_order_group_change_trigger
AFTER UPDATE ON public.order_groups
FOR EACH ROW
WHEN (
  NEW.notification_status IS DISTINCT FROM OLD.notification_status
  OR NEW.delivery_status IS DISTINCT FROM OLD.delivery_status
  OR NEW.status IS DISTINCT FROM OLD.status
  OR NEW.assigned_driver_id IS DISTINCT FROM OLD.assigned_driver_id
  OR NEW.delivery_link IS DISTINCT FROM OLD.delivery_link
  OR NEW.first_sms_sent_at IS DISTINCT FROM OLD.first_sms_sent_at
  OR NEW.second_sms_sent_at IS DISTINCT FROM OLD.second_sms_sent_at
  OR NEW.last_sms_error IS DISTINCT FROM OLD.last_sms_error
)
EXECUTE FUNCTION public.log_order_group_change();

-- Grant access
GRANT SELECT ON order_history TO authenticated;
GRANT INSERT ON order_history TO authenticated;