/**
  @module ember-jsonapi-resources
  @submodule authorization
**/

import Ember from 'ember';

/**
  A Mixin class for storage of credential/token uses with a HTTP Authorization request-header

  The default solution is to use localStorage['AuthorizationHeader'] for the credential

  @class AuthorizationMixin
  @static
*/
export default Ember.Mixin.create({

  /**
    The name of the Authorization request-header field

    @property authorizationHeaderField
    @type String
    @required
  */
  authorizationHeaderField: 'Authorization',

  /**
    The name key, stored locally, that references the Authorization request-header credential/token

    @property authorizationHeaderStorageKey
    @type String
    @required
  */
  authorizationHeaderStorageKey: 'AuthorizationHeader',

  /**
    Authentication credentials/token used with HTTP authentication

    @property authorizationCredential
    @type String
    @required
  */
  authorizationCredential: Ember.computed({
    get(key) {
      key = this.get('authorizationHeaderStorageKey');
      return window[this._storage].getItem(key);
    },
    set(key, value) {
      key = this.get('authorizationHeaderStorageKey');
      window[this._storage].setItem(key, value);
      return value;
    }
  }),

  /**
    When using the FetchMixin and using ajax instead of fetch, setup XHR
    beforeSend with Authorization Header

    @method ajaxPrefilter
  */
  ajaxPrefilter: Ember.on('init', function () {
    if (!this.get('useAjax') || this.get('useFetch')) { return; }
    Ember.$.ajaxPrefilter(function(options) {
      let key = this.get('authorizationHeaderStorageKey');
      let field = this.get('authorizationHeaderField');
      let token = window[this._storage].getItem(key);
      options.xhrFields = { withCredentials: true };
      options.beforeSend = function (xhr) {
        xhr.setRequestHeader(field, token);
      };
    }.bind(this));
  }),

  /**
    Storage type localStorage or sessionStorage

    @property _storage
    @type String
    @private
  */
  _storage: ['localStorage', 'sessionStorage'][0]

});