/**
 * 后端 API 调用助手（Node.js HTTP 直接调用，含 HMAC 签名）
 * 支持带签名和不带签名两种模式
 */
const http = require('http');
const crypto = require('crypto');

const BASE_URL = 'http://192.168.110.64:8084';
const API_BASE = '/api';
const SIGNATURE_SECRET = 'NovalonManageSystemSecretKey2026';
const ENABLE_SIGNATURE = true; // HMAC 签名

function generateSignature(method, path, body, timestamp, nonce) {
  const stringToSign = [method, path, '', body || '', String(timestamp), nonce].join('\n');
  return crypto.createHmac('sha256', SIGNATURE_SECRET).update(stringToSign).digest('base64');
}

function generateNonce() {
  return Date.now().toString(36) + '-' + Math.random().toString(36).substring(2, 15);
}

function makeRequest(method, url, body, token) {
  return new Promise((resolve, reject) => {
    const urlObj = new URL(url, BASE_URL);
    const path = urlObj.pathname + urlObj.search;
    const bodyStr = body ? JSON.stringify(body) : '';

    const headers = {
      'Content-Type': 'application/json'
    };

    if (ENABLE_SIGNATURE) {
      const timestamp = Date.now();
      const nonce = generateNonce();
      const signature = generateSignature(method.toUpperCase(), path, bodyStr, timestamp, nonce);
      headers['X-Signature'] = signature;
      headers['X-Timestamp'] = String(timestamp);
      headers['X-Nonce'] = nonce;
    }

    if (token) {
      headers['Authorization'] = token.startsWith('Bearer ') ? token : 'Bearer ' + token;
    }

    const options = {
      hostname: urlObj.hostname,
      port: urlObj.port,
      path: path,
      method: method.toUpperCase(),
      headers: headers
    };

    const req = http.request(options, (res) => {
      let data = '';
      res.on('data', chunk => { data += chunk; });
      res.on('end', () => {
        try {
          const parsed = JSON.parse(data);
          resolve({ status: res.statusCode, data: parsed });
        } catch (e) {
          resolve({ status: res.statusCode, data: data });
        }
      });
    });

    req.on('error', (err) => reject(err));
    req.setTimeout(10000, () => { req.destroy(); reject(new Error('Request timeout')); });

    if (bodyStr) req.write(bodyStr);
    req.end();
  });
}

function isSuccess(response, expectedStatus = 200) {
  return response.status === expectedStatus;
}

async function adminLogin(password) {
  console.log('[API] 管理员登录...');
  const res = await makeRequest('POST', `${API_BASE}/system/auth/login`, {
    username: 'admin',
    password: password || 'admin'
  });
  console.log(`[API] 登录响应: ${res.status}`);
  if (res.data && res.data.data && res.data.data.token) {
    return res.data.data.token;
  }
  if (res.data && res.data.token) {
    return res.data.token;
  }
  return null;
}

async function searchCourses(keyword, token) {
  console.log(`[API] 搜索课程: "${keyword}"`);
  const res = await makeRequest('POST', `${API_BASE}/groupCourse/page`, {
    page: 0, size: 50
  }, token);
  console.log(`[API] 搜索结果: status=${res.status}, total=${res.data?.data?.totalElements || res.data?.totalElements || '?'}`);
  return res;
}

async function searchByKeyword(keyword, token) {
  console.log(`[API] 按关键词搜索: "${keyword}"`);
  const res = await makeRequest('POST', `${API_BASE}/groupCourse/page`, {
    page: 0, size: 50
  }, token);
  console.log(`[API] 搜索结果: status=${res.status}, total=${res.data?.data?.totalElements || res.data?.totalElements || '?'}`);
  return res;
}

async function getCourseDetail(courseId, token) {
  console.log(`[API] 获取课程详情: id=${courseId}`);
  const res = await makeRequest('GET', `${API_BASE}/groupCourse/${courseId}/detail`, null, token);
  console.log(`[API] 课程详情: status=${res.status}`);
  return res;
}

async function getCourseTypes() {
  console.log('[API] 获取课程类型...');
  const res = await makeRequest('GET', `${API_BASE}/groupCourse/types`);
  console.log(`[API] 课程类型: status=${res.status}, count=${Array.isArray(res.data) ? res.data.length : '?'}`);
  return res;
}

async function getActiveRecommendations() {
  console.log('[API] 获取活跃推荐课程...');
  const res = await makeRequest('GET', `${API_BASE}/groupCourse/recommend/active`);
  console.log(`[API] 推荐课程: status=${res.status}`);
  return res;
}

// ── 会员端 API ──

/** 会员小程序登录，返回 {memberId, accessToken} */
async function memberLogin() {
  console.log('[API] 会员登录 (miniappLogin)...');
  const res = await makeRequest('POST', `${API_BASE}/member/auth/miniapp/login`, {
    code: 'dev-test-code-' + Date.now()
  });
  console.log(`[API] 会员登录响应: status=${res.status}`);
  if (res.status === 200 && res.data) {
    return { memberId: res.data.memberId, accessToken: res.data.accessToken };
  }
  return null;
}

/** 预约课程 */
async function bookCourse(courseId, memberId, token) {
  console.log(`[API] 预约课程: courseId=${courseId}, memberId=${memberId}`);
  const res = await makeRequest('POST', `${API_BASE}/groupCourse/book`, {
    courseId, memberId
  }, token);
  console.log(`[API] 预约结果: status=${res.status}`);
  return res;
}

/** 获取会员的预约列表 */
async function getMemberBookings(memberId, token) {
  console.log(`[API] 获取会员预约: memberId=${memberId}`);
  const res = await makeRequest('GET', `${API_BASE}/groupCourse/bookings/member/${memberId}`, null, token);
  console.log(`[API] 预约列表: status=${res.status}`);
  return res;
}

/** 扫码签到 */
async function signIn(courseId, memberId, token) {
  console.log(`[API] 签到: courseId=${courseId}, memberId=${memberId}`);
  const res = await makeRequest('POST', `${API_BASE}/groupCourse/signin/${memberId}`, {
    courseId
  }, token);
  console.log(`[API] 签到结果: status=${res.status}`);
  return res;
}

module.exports = {
  makeRequest,
  adminLogin,
  searchCourses,
  searchByKeyword,
  getCourseDetail,
  getCourseTypes,
  getActiveRecommendations,
  memberLogin,
  bookCourse,
  getMemberBookings,
  signIn,
  isSuccess,
  BASE_URL,
  API_BASE
};