sebastian-software/core

/*
==================================================================================================
  Core - JavaScript Foundation
  Copyright 2013-2014 Sebastian Werner
==================================================================================================
*/

/**
 * Wrapper around Google's Geocoding API.
 *
 * Note: The Geocoding API must only be used in combination with showing locations
 * on the Google Maps interface. For details see the license of the Google Maps API.
 */
core.Module("core.service.location.GeoCode",
{
  detect : function(data)
  {
    return new core.event.Promise(function(resolve, reject) {
      var url = "//maps.googleapis.com/maps/api/geocode/json?sensor=true&latlng=";
      url += data.latitude + "," + data.longitude;

      // TODO: Make use for XHR wrapper
      var xhr = new XMLHttpRequest;
      xhr.open("GET", url, true);
      xhr.onreadystatechange = function()
      {
        if (xhr.readyState == 4)
        {
          try{
            var parsed = core.JSON.parse(xhr.responseText);
          }
          catch(ex)
          {
            console.error("Error during parsing result: " + ex);
            parsed = {};
          }

          if (parsed.status == "OK")
          {
            var components = parsed.results[0].address_components;
            var relevant = ["street_number", "route", "locality", "postal_code"];

            for (var i=0, il=components.length; i<il; i++)
            {
              var component = components[i];
              var value = component.long_name;
              var types = component.types;

              for (var j=0, jl=relevant.length; j<jl; j++)
              {
                if (types.indexOf(relevant[j]) != -1)
                {
                  data[relevant[j]] = value;
                  break;
                }
              }
            }

            resolve(data);
          }
          else
          {
            reject("Failed to get or invalid result from Google!");
          }
        }
      };

      xhr.send(null);
    });
  }
});