const { BASE_URL } = require('./config.js');

const TOKEN_KEY = 'pets_token';

function getToken() {
  return wx.getStorageSync(TOKEN_KEY) || '';
}
function setToken(t) {
  wx.setStorageSync(TOKEN_KEY, t);
}
function clearToken() {
  wx.removeStorageSync(TOKEN_KEY);
}

// token 失效时的重新登录钩子，由 store 注册（放在这里避免 request ← api ← store 循环依赖）
let reAuth = null;
function setReAuthHandler(fn) {
  reAuth = fn;
}

const TIMEOUT = 15000;

// 统一请求：注入 token，解析 {code,message,data}，成功返回 data，失败 reject(Error)。
// token 失效（40100）时自动重新登录并重试一次，避免 JWT 过期后小程序静默白屏。
function request(options, _retried) {
  const { url, method = 'GET', data, header = {} } = options;
  return new Promise((resolve, reject) => {
    const token = getToken();
    wx.request({
      url: BASE_URL + url,
      method,
      data,
      timeout: TIMEOUT,
      header: Object.assign(
        { 'Content-Type': 'application/json' },
        token ? { Authorization: 'Bearer ' + token } : {},
        header,
      ),
      success(res) {
        const body = res.data;
        if (body && typeof body === 'object' && 'code' in body) {
          if (body.code === 0) return resolve(body.data);
          if (body.code === 40100) {
            clearToken();
            // 只重试一次，防止登录接口本身出问题时无限循环
            if (!_retried && reAuth) {
              return reAuth()
                .then(() => request(options, true).then(resolve, reject))
                .catch(() => reject(new Error(body.message || '登录已过期，请重进小程序')));
            }
          }
          return reject(new Error(body.message || '请求失败'));
        }
        resolve(body);
      },
      fail(err) {
        const msg = (err && err.errMsg) || '网络错误';
        reject(new Error(/timeout/i.test(msg) ? '网络超时，请稍后重试' : msg));
      },
    });
  });
}

// 文件上传（multipart）
function uploadFile(filePath) {
  return new Promise((resolve, reject) => {
    const token = getToken();
    wx.uploadFile({
      url: BASE_URL + '/api/upload',
      filePath,
      name: 'file',
      timeout: 60000,
      header: token ? { Authorization: 'Bearer ' + token } : {},
      success(res) {
        try {
          const body = JSON.parse(res.data);
          if (body.code === 0) return resolve(body.data);
          reject(new Error(body.message || '上传失败'));
        } catch (e) {
          reject(new Error('上传响应解析失败'));
        }
      },
      fail(err) {
        reject(new Error((err && err.errMsg) || '上传失败'));
      },
    });
  });
}

module.exports = { request, uploadFile, getToken, setToken, clearToken, setReAuthHandler };