/**
 * 페이지 권한 미들웨어 (shared)
 * admin/system 역할은 자동 통과, 일반 사용자는 개인/부서 권한 체크
 *
 * 사용법:
 *   const { createRequirePage } = require('../../shared/middleware/pagePermission');
 *   const requirePage = createRequirePage(() => getPool());
 *   router.get('/some', requirePage('page_name'), controller.handler);
 */

function createRequirePage(getPool) {
  return function requirePage(pageName) {
    return async (req, res, next) => {
      const userId = req.user.user_id || req.user.id;
      const role = (req.user.role || '').toLowerCase();

      // admin/system 자동 통과
      if (role === 'admin' || role === 'system') return next();

      try {
        const db = typeof getPool === 'function' ? await getPool() : getPool;

        // 1. 개인 권한 체크
        const [rows] = await db.query(
          'SELECT can_access FROM user_page_permissions WHERE user_id = ? AND page_name = ?',
          [userId, pageName]
        );
        if (rows.length > 0) {
          return rows[0].can_access
            ? next()
            : res.status(403).json({ success: false, error: '접근 권한이 없습니다' });
        }

        // 2. 부서 권한 체크
        const [userRows] = await db.query(
          'SELECT department_id FROM sso_users WHERE user_id = ?',
          [userId]
        );
        if (userRows.length > 0 && userRows[0].department_id) {
          const [deptRows] = await db.query(
            'SELECT can_access FROM department_page_permissions WHERE department_id = ? AND page_name = ?',
            [userRows[0].department_id, pageName]
          );
          if (deptRows.length > 0) {
            return deptRows[0].can_access
              ? next()
              : res.status(403).json({ success: false, error: '접근 권한이 없습니다' });
          }
        }

        // 3. 권한 레코드 없음 → 거부
        return res.status(403).json({ success: false, error: '접근 권한이 없습니다' });
      } catch (err) {
        console.error('Permission check error:', err);
        return res.status(500).json({ success: false, error: '권한 확인 실패' });
      }
    };
  };
}

module.exports = { createRequirePage };