import qs from 'querystring';

import AxiosError from 'axios-error';
import axios, { AxiosInstance } from 'axios';
import get from 'lodash/get';
import {
  OnRequestFunction,
  camelcaseKeys,
  createRequestInterceptor,
  pascalcaseKeys,
} from 'messaging-api-common';

type ClientConfig = {
  accountSid: string;
  authToken: string;
  phoneNumber: string;
  origin?: string;
};

function handleError(err: AxiosError): never {
  if (err.response && err.response.data) {
    const error = get(err, 'response.data', {});
    const msg = `WhatsApp API - ${error.code} ${error.message} ${error.more_info}`;
    throw new AxiosError(msg, err);
  }
  throw new AxiosError(err.message, err);
}

export default class TwilioClient {
  static connect(config: ClientConfig): TwilioClient {
    return new TwilioClient(config);
  }

  _onRequest: OnRequestFunction | undefined;

  _axios: AxiosInstance;

  _authToken: string;

  _phoneNumber: string;

  constructor(config: ClientConfig) {
    const twilioOrigin = `https://${config.accountSid}:${config.authToken}@api.twilio.com`;

    this._authToken = config.authToken;
    this._phoneNumber = config.phoneNumber;

    this._axios = axios.create({
      baseURL: `${config.origin || twilioOrigin}/2010-04-01/Accounts/${
        config.accountSid
      }/`,
      headers: {
        'Content-Type': 'application/x-www-form-urlencoded',
      },
    });

    this._axios.interceptors.request.use(
      createRequestInterceptor({
        onRequest: this._onRequest,
      })
    );
  }

  get axios(): AxiosInstance {
    return this._axios;
  }

  get authToken(): string {
    return this._authToken;
  }

  async createMessage(message: {
    from?: string;
    body: string;
    to: string;
    maxPrice?: number;
    provideFeedback?: boolean;
    validityPeriod?: number;
    forceDelivery?: boolean;
    smartEncoded?: boolean;
    persistentAction?: string[];
    mediaUrl?: string[];
  }) {
    try {
      const { data } = await this._axios.post<{
        sid: string;
        date_created: string;
        date_updated: string;
        date_sent: null;
        account_sid: string;
        to: string;
        from: string;
        messaging_service_sid: null;
        body: string;
        status: string;
        num_segments: string;
        num_media: string;
        direction: string;
        api_version: string;
        price: null;
        price_unit: null;
        error_code: null;
        error_message: null;
        uri: string;
        subresource_uris: {
          uri: string;
        };
      }>(
        '/Messages.json',
        qs.stringify(
          pascalcaseKeys({
            from: this._phoneNumber,
            ...message,
          })
        )
      );
      return camelcaseKeys(data);
    } catch (err) {
      handleError(err);
    }
  }
}