import { AsyncStorage } from 'react-native';
import jsrsasign from 'jsrsasign';
import HttpError from './HttpError';
import { Alert } from 'react-native';

export default async function request(url, body = {}, params = {}, type = 'POST') {
  const pubKey = await AsyncStorage.getItem('@EncryptStore:publicKey');
  const privateKey = await AsyncStorage.getItem('@EncryptStore:privateKey');
  let token = await AsyncStorage.getItem('@TopUpStore:Token');
  token = token ? token : '';

  if (pubKey === null || privateKey === null) {
    return;
  }

  params.token = token;
  url += (url.indexOf('?') === -1 ? '?' : '&') + queryParams(params);
  const bodyString = type === 'POST' || type === 'DELETE' ? JSON.stringify(body) : '';

  const signature = jsrsasign.KJUR.crypto.Util.md5(pubKey);
  const sig = new jsrsasign.KJUR.crypto.Signature({ alg: 'SHA256withRSA' });
  sig.init(privateKey);
  sig.updateString(bodyString);
  const sigValueHex = sig.sign();
  const base64Sign = jsrsasign.hextob64(sigValueHex);

  const post = {
    method: type,
    headers: {
      Accept: 'application/json',
      'Content-Type': 'application/json',
      Sign: base64Sign,
      Signature: signature
    },
  };

  if (type === 'POST' || type === 'DELETE') post.body = bodyString;

  LOG('\n===== START HTTP REQUEST =====');
  LOG(`HTTP send url: ${url}`);
  LOG(`HTTP send body: ${bodyString}`);

  const response = await fetch(url, post);
  const responseStatus = await response.status;
  LOG(`HTTP response code: ${responseStatus}`);

  if (responseStatus !== 200) {
    const responseBody = await response.json();
    let errorText = '';

    if (responseBody.Message !== undefined) {
      errorText = responseBody.Message;
    }

    if (responseBody.ModelState !== undefined) {
      if (Object.keys(responseBody.ModelState)[0]) {
        errorText =
          responseBody.ModelState[Object.keys(responseBody.ModelState)[0]][0];
      }
    }

    LOG(`HTTP error body: ${JSON.stringify(responseBody)}`);
    LOG('===== END HTTP REQUEST =====\n');

    Alert.alert('Error', errorText);
    throw new HttpError(errorText);
  }

  LOG(`HTTP response code: ${responseStatus}`);
  LOG('===== END HTTP REQUEST =====\n');

  return response;
}

function queryParams(params) {
  return Object.keys(params)
    .map(k => encodeURIComponent(k) + '=' + encodeURIComponent(params[k]))
    .join('&');
}