Vizzuality/gfw-climate

/**
  PlaceService
 */
define(
  ['underscore', 'mps', 'uri', 'embed/presenters/PresenterClass'],
  function(_, mps, UriTemplate, PresenterClass) {
    'use strict';

    var urlDefaultsParams = {
      location: null,
      widget: null
    };

    var PlaceService = PresenterClass.extend({
      _uriTemplate: '{name}{/location}{/widget}',

      /**
       * Create new PlaceService with supplied Backbone.Router.
       *
       * @param  {Backbond.Router} router Instance of Backbone.Router
       */
      init: function(router) {
        this.router = router;
        this._presenters = [];
        this._name = null;
        this._super();
      },

      /**
       * Subscribe to application events.
       */
      _subscriptions: [
        {
          'Place/register': function(presenter) {
            this._presenters = _.union(this._presenters, [presenter]);
          }
        },
        {
          'Place/update': function() {
            this._updatePlace();
          }
        }
      ],

      /**
       * Init by the router to set the name
       * and publish the first place.
       *
       * @param  {String} name   Place name
       * @param  {Object} params Url params
       */
      initPlace: function(name, params) {
        this._name = name;
        this._newPlace(params);
      },

      /**
       * Silently updates the url from the presenter params.
       */
      _updatePlace: function() {
        var route, params;
        params = this._destandardizeParams(
          this._getPresenterParams(this._presenters)
        );

        route = this._getRoute(params);
        this.router.navigate(route, { silent: true });
      },

      /**
       * Handles a new place.
       *
       * @param  {Object}  params The place parameters
       */
      _newPlace: function(params) {
        this.params = this._standardizeParams(params);
        mps.publish('Place/go', [this.params]);
      },

      /**
       * Return route URL for supplied route name and route params.
       *
       * @param  {Object} params The route params
       * @return {string} The route URL
       */
      _getRoute: function(param) {
        var url = new UriTemplate(this._uriTemplate).fillFromObject(param);
        return decodeURIComponent(url);
      },

      /**
       * Return standardized representation of supplied params object.
       *
       * @param  {Object} params The params to standardize
       * @return {Object} The standardized params.
       */
      _standardizeParams: function(params) {
        var p = _.extendNonNull({}, urlDefaultsParams, params);
        p.name = this._name ? this._name : null;
        p.widget = p.widget ? parseInt(p.widget) : null;
        p.globalThresh = p.globalThresh ? p.globalThresh : 30;

        // We have to develop this with our params
        if (p.location) {
          var location = p.location.split('+');
          p.location = {
            iso: location[0],
            jurisdiction: ~~location[1],
            area: location[2]
          };
        }
        if (p.options) {
          p.options = JSON.parse(atob(p.options));
        }
        return p;
      },

      /**
       * Return formated URL representation of supplied params object based on
       * a route name.
       *
       * @param  {Object} params Place to standardize
       * @return {Object} Params ready for URL
       */
      _destandardizeParams: function(params) {
        var p = _.extendNonNull({}, urlDefaultsParams, this.params, params);
        p.name = this._name ? this._name : null;
        p.widget = p.widget ? parseInt(p.widget) : null;
        p.globalThresh = p.globalThresh ? p.globalThresh : 30;

        // We have to develop this with our params
        p.location = p.location
          ? p.location.iso +
            '+' +
            p.location.jurisdiction +
            '+' +
            p.location.area
          : null;

        if (p.options) {
          p.options = params.options;
          p.options = btoa(JSON.stringify(p.options));
        }

        return p;
      },

      /**
       * Return param object representing state from all registered presenters
       * that implement getPlaceParams().
       *
       * @param  {Array} presenters The registered presenters
       * @return {Object} Params representing state from all presenters
       */
      _getPresenterParams: function(presenters) {
        var p = {};

        _.each(
          presenters,
          function(presenter) {
            _.extend(p, presenter.getPlaceParams());
          },
          this
        );

        return p;
      }
    });

    return PlaceService;
  }
);