SGH / COMPONENTS

<!-- Copyright (c) 2015 Google Inc. All rights reserved. -->

<link rel="import" href="../polymer/polymer.html">

<!--
`google-map-search` provides Google Maps Places API functionality.

See https://developers.google.com/maps/documentation/javascript/places for more
information on the API.

#### Example:

    <template is="dom-bind">
      <google-map-search map="[[map]]" query="Pizza" results="{{results}}">
      </google-map-search>
      <google-map map="{{map}}" latitude="37.779"
                  longitude="-122.3892">
        <template is="dom-repeat" items="{{results}}" as="marker">
          <google-map-marker latitude="{{marker.latitude}}"
                             longitude="{{marker.longitude}}">
            <h2>{{marker.name}}</h2>
            <span>{{marker.formatted_address}}</span>
          </google-map-marker>
        </template>
      </google-map>
    </template>
 -->

<script>

  Polymer({

    is: 'google-map-search',

    properties: {

      /**
       * The Google map object.
       */
      map: {
        type: Object,
        value: null
      },

      /**
       * The search query.
       */
      query: {
        type: String,
        value: null
      },

      /**
       * Latitude of the center of the search area.
       * Ignored if `globalSearch` is true.
       */
      latitude: {
        type: Number,
        value: null
      },

      /**
       * Longitude of the center of the search area.
       * Ignored if `globalSearch` is true.
       */
      longitude: {
        type: Number,
        value: null
      },

      /**
       * Search radius, in meters.
       * If `latitude` and `longitude` are not specified,
       * the center of the currently visible map area is used.
       *
       * If not set, search will be restricted to the currently visible
       * map area, unless `globalSearch` is set to true.
       */
      radius: {
        type: Number,
        value: null
      },

      /**
       * By default, search is restricted to the currently visible map area.
       * Set this to true to search everywhere.
       *
       * Ignored if `radius` is set.
       */
      globalSearch: {
        type: Boolean,
        value: false
      },

      /**
       * Space-separated list of result types.
       * The search will only return results of the listed types.
       * See https://developers.google.com/places/documentation/supported_types
       * for a list of supported types.
       * Leave empty or null to search for all result types.
       */
      types: {
        type: String,
        value: null
      },

      /**
       * The search results.
       */
      results: {
        type: Array,
        value: function() { return []; },
        notify: true
      },

      /**
       * The lat/lng location.
       */
      location: {
        type: Object,
        value: null,
        readOnly: true
      }
    },

    observers: [
      'search(query,map,location,radius,types,globalSearch)',
      '_updateLocation(latitude,longitude)'
    ],

    /**
     * Fired when the details of a place are returned.
     *
     * @event google-map-search-place-detail
     * @param {google.maps.MarkerPlace} detail The place details.
     */

    /**
     * Fired when the search element returns a result.
     *
     * @event google-map-search-results
     * @param {Array<{latitude: number, longitude: number}>} detail An array of search results
     */

    /**
     * Perform a search using for `query` for the search term.
     */
    search: function() {
      if (this.query && this.map) {
        var places = new google.maps.places.PlacesService(this.map);

        if (this.types && typeof this.types == 'string') {
          var types = this.types.split(' ');
        }

        if (!this.globalSearch) {
          var bounds = this.map.getBounds();
        } else if (this.radius) {
          var radius = this.radius;
          var location = this.location ? this.location : this.map.getCenter();
        }

        places.textSearch({
          query: this.query,
          types: types,
          bounds: bounds,
          radius: radius,
          location: location
        }, this._gotResults.bind(this));
      }
    },

    /**
     * Fetches details for a given place.
     * @param {String} placeId The place id.
     * @return {Promise} place The place information.
     */
    getDetails: function(placeId) {
      var places = new google.maps.places.PlacesService(this.map);

      return new Promise(function(resolve, reject) {
        places.getDetails({placeId: placeId}, function(place, status) {
          if (status === google.maps.places.PlacesServiceStatus.OK) {
            resolve(place);
            this.fire('google-map-search-place-detail', place);
          } else {
            reject(status);
          }
        }.bind(this));
      }.bind(this));
    },

    _gotResults: function(results, status) {
      this.results = results.map(function(result) {
        // obtain lat/long from geometry
        result.latitude  = result.geometry.location.lat();
        result.longitude = result.geometry.location.lng();
        return result;
      });
      this.fire('google-map-search-results', this.results);
    },

    _updateLocation: function() {
      if (!this.map) {
        return;
      } else if (typeof this.latitude !== 'number' || isNaN(this.latitude)) {
        throw new TypeError('latitude must be a number');
      } else if (typeof this.longitude !== 'number' || isNaN(this.longitude)) {
        throw new TypeError('longitude must be a number');
      }

      // Update location. This will trigger a new search.
      this._setLocation({lat: this.latitude, lng: this.longitude});
    }
  });
</script>