mohsen-angular-leaflet-directive/src/services/leafletBoundsHelpers.js

angular-leaflet-directive - An AngularJS directive to easily interact with Leaflet maps

angular.module('leaflet-directive').factory('leafletBoundsHelpers', function(leafletLogger, leafletHelpers) {

  var isArray = leafletHelpers.isArray;
  var isNumber = leafletHelpers.isNumber;
  var isFunction = leafletHelpers.isFunction;
  var isDefined = leafletHelpers.isDefined;

  function _isValidBounds(bounds) {
    return angular.isDefined(bounds) && angular.isDefined(bounds.southWest) &&
           angular.isDefined(bounds.northEast) && angular.isNumber(bounds.southWest.lat) &&
           angular.isNumber(bounds.southWest.lng) && angular.isNumber(bounds.northEast.lat) &&
           angular.isNumber(bounds.northEast.lng);
  }

  return {
    createLeafletBounds: function(bounds) {
      if (_isValidBounds(bounds)) {
        return L.latLngBounds([bounds.southWest.lat, bounds.southWest.lng],
                              [bounds.northEast.lat, bounds.northEast.lng]);
      }
    },

    isValidBounds: _isValidBounds,

    createBoundsFromArray: function(boundsArray) {
      if (!(isArray(boundsArray) && boundsArray.length === 2 &&
            isArray(boundsArray[0]) && isArray(boundsArray[1]) &&
            boundsArray[0].length === 2 && boundsArray[1].length === 2 &&
            isNumber(boundsArray[0][0]) && isNumber(boundsArray[0][1]) &&
            isNumber(boundsArray[1][0]) && isNumber(boundsArray[1][1]))) {
        leafletLogger.error('The bounds array is not valid.');
        return;
      }

      return {
        northEast: {
          lat: boundsArray[0][0],
          lng: boundsArray[0][1],
        },
        southWest: {
          lat: boundsArray[1][0],
          lng: boundsArray[1][1],
        },
      };
    },

    createBoundsFromLeaflet: function(lfBounds) {
      if (!(isDefined(lfBounds) && isFunction(lfBounds.getNorthEast) && isFunction(lfBounds.getSouthWest))) {
        leafletLogger.error('The leaflet bounds is not valid object.');
        return;
      }

      var northEast = lfBounds.getNorthEast();
      var southWest = lfBounds.getSouthWest();

      return {
        northEast: {
          lat: northEast.lat,
          lng: northEast.lng,
        },
        southWest: {
          lat: southWest.lat,
          lng: southWest.lng,
        },
      };
    },
  };
});