import { InternalAxiosRequestConfig, AxiosPromise, AxiosError } from 'axios';
import { buildFullPath, deepCopy } from '../utils';
import { canceller, cancellerCalled } from '../canceller'

declare const wx: any;

export default function wxAdapter(config: InternalAxiosRequestConfig): AxiosPromise {
  // adapter接受的config要完全符合axios的配置规范，然后在这里针对不同的引擎做个性化修改
  return new Promise((resolve, reject) => {
    let requestConfig = {} as any;
    let isAborted = false
    let requestTask: any = null
    const {
      headers,
      data,
      params,
      url,
      timeout,
      method,
      ...rest
    } = config;

    const requestHeader = deepCopy(headers);
    delete requestHeader.Referer; // 小程序文档，header中不能有Referer
    requestConfig.header = requestHeader;

    const requestData = data || params; // wx环境，不论get还是post，参数传递的属性名均为data
    requestConfig.data = deepCopy(requestData);
    requestConfig.url = buildFullPath(config.baseURL || '', config.url || '');
    requestConfig.timeout = config.timeout;
    requestConfig.method = config?.method?.toUpperCase();
    requestConfig = { ...requestConfig, ...rest };

    requestConfig.success = (res) => {
      let response = {} as any;
      const {
        data: resData,
        statusCode,
        header,
        ...restRes
      } = res;
      response.data = resData;
      response.status = statusCode;
      response.headers = header;
      response.config = config;
      response = { ...response, ...restRes };

      const { validateStatus } = response.config;
      if (!response.status || !validateStatus || validateStatus(response.status)) {
        resolve(response);
      } else {
        const errMsg = `Request failed with status code ${response.status}`

        reject(new AxiosError(errMsg, '', requestConfig, requestTask, response));
      }
    };

    requestConfig.fail = (err) => {
      if (isAborted) {
        reject(new AxiosError(err.errMsg, AxiosError.ERR_CANCELED, requestConfig, requestTask))
      }

      reject(new AxiosError(err.errMsg, err.errno, requestConfig, requestTask));
    };

    // 判断是否已经调用了取消函数
    if (cancellerCalled.includes(requestConfig.cancelKey)) {
      // 已经调用过取消函数了，直接抛出错误即可
      reject(new AxiosError('请求在发出之前被主动取消！', AxiosError.ERR_CANCELED, requestConfig, requestTask))
      // 删除记录
      cancellerCalled.splice(cancellerCalled.indexOf(requestConfig.cancelKey), 1)
      return
    }

    requestTask = wx.request(requestConfig);

    // 设置了cancelKey，但是环境不支持AbortController
    if ('undefined' === typeof requestConfig.signal && requestConfig.cancelKey) {
      canceller[requestConfig.cancelKey] = () => {
        isAborted = true
        requestTask.abort.call(requestTask)
        Reflect.deleteProperty(canceller, requestConfig.cancelKey)
      }
    }
  });
}