/**
 * QR Code 產生器 - Server API 呼叫模組
 */

/**
 * 呼叫 Server API 產生 QR Code
 * @param {Object} studentData - 學員資料
 * @param {Object} actions - 執行選項
 * @returns {Object} API 回應
 */
function callServerAPI(studentData, actions) {
  const payload = {
    class_prefix: studentData.classPrefix,
    student_no: studentData.studentNo,
    name: studentData.name,
    email: studentData.email,
    phone: studentData.phone,
    actions: {
      generate_qrcode: true,
      save_to_db: actions.saveToDb || false,
      upload_to_server: actions.uploadToServer || false
    }
  };
  
  const options = {
    method: 'post',
    contentType: 'application/json',
    payload: JSON.stringify(payload),
    muteHttpExceptions: true,
    timeout: 30
  };
  
  try {
    const response = UrlFetchApp.fetch(CONFIG.API_ENDPOINT, options);
    const responseCode = response.getResponseCode();
    const responseText = response.getContentText();
    
    if (responseCode !== 200) {
      return {
        success: false,
        error: {
          stage: 'api_call',
          code: 'HTTP_' + responseCode,
          message: 'Server 回應錯誤: ' + responseCode
        }
      };
    }
    
    const result = JSON.parse(responseText);
    
    if (!result.success) {
      return {
        success: false,
        error: {
          stage: result.error?.stage || 'api_call',
          code: result.error?.code || 'API_ERROR',
          message: result.error?.message || '未知錯誤'
        }
      };
    }
    
    return {
      success: true,
      data: result.data
    };
    
  } catch (error) {
    // 判斷錯誤類型
    let errorCode = 'UNKNOWN_ERROR';
    let errorMessage = error.message;
    
    if (error.message.includes('timeout') || error.message.includes('Timeout')) {
      errorCode = 'TIMEOUT';
      errorMessage = 'API 連線逾時';
    } else if (error.message.includes('connect') || error.message.includes('network')) {
      errorCode = 'NETWORK_ERROR';
      errorMessage = '網路連線錯誤';
    } else if (error.message.includes('JSON')) {
      errorCode = 'PARSE_ERROR';
      errorMessage = 'API 回應格式錯誤';
    }
    
    return {
      success: false,
      error: {
        stage: 'api_call',
        code: errorCode,
        message: errorMessage
      }
    };
  }
}

/**
 * 測試 API 連線
 * @returns {Object} 測試結果
 */
function testAPIConnection() {
  const testPayload = {
    class_prefix: 'TEST',
    student_no: 'TEST001',
    name: '測試',
    email: 'test@test.com',
    phone: '0912345678',
    actions: {
      generate_qrcode: true,
      save_to_db: false,
      upload_to_server: false
    },
    test_mode: true  // 告訴 Server 這是測試請求
  };
  
  const options = {
    method: 'post',
    contentType: 'application/json',
    payload: JSON.stringify(testPayload),
    muteHttpExceptions: true,
    timeout: 10
  };
  
  try {
    const response = UrlFetchApp.fetch(CONFIG.API_ENDPOINT, options);
    const responseCode = response.getResponseCode();
    
    if (responseCode === 200) {
      const result = JSON.parse(response.getContentText());
      return {
        success: true,
        message: 'API 連線正常',
        serverVersion: result.version || 'unknown'
      };
    } else {
      return {
        success: false,
        message: 'API 回應錯誤: ' + responseCode
      };
    }
  } catch (error) {
    return {
      success: false,
      message: 'API 連線失敗: ' + error.message
    };
  }
}

/**
 * 批次呼叫 API（用於需要更好效能的情況）
 * @param {Array} studentsData - 學員資料陣列
 * @param {Object} actions - 執行選項
 * @returns {Array} API 回應陣列
 */
function callServerAPIBatch(studentsData, actions) {
  const payload = {
    batch: true,
    students: studentsData.map(s => ({
      class_prefix: s.classPrefix,
      student_no: s.studentNo,
      name: s.name,
      email: s.email,
      phone: s.phone
    })),
    actions: {
      generate_qrcode: true,
      save_to_db: actions.saveToDb || false,
      upload_to_server: actions.uploadToServer || false
    }
  };
  
  const options = {
    method: 'post',
    contentType: 'application/json',
    payload: JSON.stringify(payload),
    muteHttpExceptions: true,
    timeout: 120  // 批次處理需要較長時間
  };
  
  try {
    const response = UrlFetchApp.fetch(CONFIG.API_ENDPOINT, options);
    const responseCode = response.getResponseCode();
    
    if (responseCode !== 200) {
      throw new Error('Server 回應錯誤: ' + responseCode);
    }
    
    const result = JSON.parse(response.getContentText());
    return result.results || [];
    
  } catch (error) {
    // 批次失敗，回傳所有失敗
    return studentsData.map(s => ({
      success: false,
      student_no: s.studentNo,
      error: {
        stage: 'batch_api_call',
        code: 'BATCH_ERROR',
        message: error.message
      }
    }));
  }
}