/**
 * Silex, live web creation
 * http://projects.silexlabs.org/?/silex/
 *
 * Copyright (c) 2012 Silex Labs
 * http://www.silexlabs.org/
 *
 * Silex is available under the GPL license
 * http://www.silexlabs.org/silex/silex-licensing/
 */

/**
 * @fileoverview Service used to interact with the unifile server.
 *     The Silex "tasks" are nodejs methods which Silex adds to the unifle API.
 *     This class is a singleton.
 *
 */

import {Hosting, Provider, PublicationOptions, VHost} from '../types';
/**
 * the Silex SilexTasks singleton
 * based on http://www.inkfilepicker.com/
 * load and save data to and from the cloud storage services
 * FIXME: use types common to front and back end
 */
export class SilexTasks {

  static instance: SilexTasks;
  static getInstance() {
    SilexTasks.instance = SilexTasks.instance || new SilexTasks();
    return SilexTasks.instance;
  }
  /**
   * publish a website to a given folder
   * @param cbk called when success
   * @param opt_errCbk to receive the json response
   */
  publish(options: PublicationOptions, cbk: (p1: string) => any, opt_errCbk?: (p1: string) => any) {
    this.callServer('/tasks/publish', JSON.stringify(options), 'POST', (json) => cbk(json), opt_errCbk);
  }

  /**
   * get the state of the current publication
   * @param cbk to receive the json response
   * @param opt_errCbk to receive the json response
   */
  publishState(cbk: (p1: {message: string, stop: boolean}) => any, opt_errCbk?: (p1: string) => any) {
    this.callServer('/tasks/publishState', '', 'GET', cbk, opt_errCbk);
  }

  /**
   * get the state of the current publication
   * @param cbk to receive the json response
   * @param opt_errCbk to receive the json response
   */
  hosting(cbk: (p1: Hosting) => any, opt_errCbk?: (p1: string) => any) {
    this.callServer('/hosting/', '', 'GET', cbk, opt_errCbk);
  }

  /**
   * get the login URL
   * @param cbk to receive the json response
   */
  authorize(provider: Provider, cbk: (p1: string) => any, opt_errCbk?: (p1: string) => any) {
    this.callServer(provider.authorizeUrl, '', 'POST', cbk, opt_errCbk);
  }

  /**
   * get the vhosts for a provider to which we are connected
   * @param cbk to receive the json response
   */
  vhosts(provider: Provider, cbk: (p1: VHost[]) => any, opt_errCbk?: (p1: string) => any) {
    this.callServer(provider.vhostsUrl, '', 'GET', cbk, opt_errCbk);
  }

  /**
   * get the domain name for a vhost
   * @param cbk to receive the json response
   */
  domain(vhost: VHost, cbk: (p1?: {domain: string, url: string, status: string}) => any, opt_errCbk?: (p1: string) => any) {
    this.callServer(vhost.domainUrl, '', 'GET', cbk, opt_errCbk);
  }

  /**
   * update the domain name for a vhost
   * @param cbk to receive the json response
   */
  updateDomain(vhost: VHost, newDomain: string, cbk: (p1: {domain: string, https: boolean}) => any, opt_errCbk?: (p1: string) => any) {
    this.callServer(vhost.domainUrl, JSON.stringify({domain: newDomain}), 'POST', cbk,   opt_errCbk);
  }

  /**
   * remove the domain name for a vhost
   * @param cbk to receive the json response
   */
  removeDomain(vhost: VHost, newDomain: string, cbk: (p1: {domain: string, https: boolean}) => any, opt_errCbk?: (p1: string) => any) {
    this.callServer(vhost.domainUrl, JSON.stringify({domain: newDomain}), 'DELETE',   cbk, opt_errCbk);
  }

  /**
   * @param cbk to receive the json response
   * @param opt_errCbk to receive the json response
   */
  callServer(url: string, data: string, method: string, cbk, opt_errCbk?: (p1: string) => any) {
    const oReq = new XMLHttpRequest();
    oReq.addEventListener('load', (e) => {
      let message: string = oReq.responseText;
      let json: any = null;
      try {
        json = (JSON.parse(oReq.responseText));
        message = (json.message as string);
      } catch (e) {
      }

      // handle the case where the response is just a string, e.g. an URL in the
      // case of oauth

      // may be an empty response or a "Internal Server Error" string
      // success of the request
      if (oReq.status === 200) {
        cbk(json || oReq.responseText);
      } else {
        console.error('Error while trying to connect with back end', message);
        if (opt_errCbk) {
          opt_errCbk(json ? json.message : message);
        }
      }
    });
    oReq.addEventListener('error', (e) => {
      console.error('could not load website', e);
      if (opt_errCbk) {
        opt_errCbk(
            'Network error, please check your internet connection or try again later.');
      }
    });
    oReq.open(method, url);
    oReq.setRequestHeader('Content-Type', 'application/json');
    oReq.send(data);
  }
}