Models/PointParameter.js

"use strict";

/*global require*/
var CesiumMath = require("terriajs-cesium/Source/Core/Math").default;
var defined = require("terriajs-cesium/Source/Core/defined").default;

var FunctionParameter = require("./FunctionParameter");
var inherit = require("../Core/inherit");
var defaultValue = require("terriajs-cesium/Source/Core/defaultValue").default;

/**
 * A parameter that specifies a single location on the globe.
 *
 * @alias PointParameter
 * @constructor
 * @extends FunctionParameter
 *
 * @param {Object} options Object with the following properties:
 * @param {Terria} options.terria The Terria instance.
 * @param {String} options.id The unique ID of this parameter.
 * @param {String} [options.name] The name of this parameter.  If not specified, the ID is used as the name.
 * @param {String} [options.description] The description of the parameter.
 * @param {Boolean} [options.defaultValue] The default value.
 */
var PointParameter = function(options) {
  FunctionParameter.call(this, options);
};

inherit(FunctionParameter, PointParameter);

Object.defineProperties(PointParameter.prototype, {
  /**
   * Gets the type of this parameter.
   * @memberof DateTimeParameter.prototype
   * @type {String}
   */
  type: {
    get: function() {
      return "point";
    }
  }

  /**
   * Gets or sets the value of this parameter.
   * @memberof PointParameter.prototype
   * @member {Cartographic} value
   */
});

/**
 * Represents value as string.
 * @param {Object} value Value to format as string.
 * @return {String} String representing value.
 */
PointParameter.prototype.formatValueAsString = function(value) {
  value = defaultValue(value, this.value);
  if (!defined(value)) {
    return "-";
  }

  return (
    Math.abs(CesiumMath.toDegrees(value.latitude)) +
    "°" +
    (value.latitude < 0 ? "S " : "N ") +
    Math.abs(CesiumMath.toDegrees(value.longitude)) +
    "°" +
    (value.longitude < 0 ? "W" : "E")
  );
};

/**
 * Get feature as geojson for display on map.
 * @param {Object} value Value to use.
 * @return GeoJson object.
 */
PointParameter.prototype.getGeoJsonFeature = function(value) {
  value = defaultValue(value, this.value);
  if (!defined(value) || value === "") {
    return undefined;
  }

  var coordinates = [
    CesiumMath.toDegrees(value.longitude),
    CesiumMath.toDegrees(value.latitude)
  ];

  if (defined(value.height)) {
    coordinates.push(value.height);
  }

  return {
    type: "Feature",
    geometry: {
      type: "Point",
      coordinates: coordinates
    }
  };
};

PointParameter.formatValueAsString =
  PointParameter.prototype.formatValueAsString;
PointParameter.getGeoJsonFeature = PointParameter.prototype.getGeoJsonFeature;

/**
 * Process value so that it can be used in an URL.
 * @param {String} value Value to use to format.
 * @return {String} Stringified JSON that can be used to pass parameter value in URL.
 */
PointParameter.formatValueForUrl = function(value) {
  return JSON.stringify({
    type: "FeatureCollection",
    features: [PointParameter.getGeoJsonFeature(value)]
  });
};

PointParameter.AvailableFormatters = {
  default: formatAsLongitudeCommaLatitude,
  longitudeCommaLatitude: formatAsLongitudeCommaLatitude,
  latitudeCommaLongitude: formatAsLatitudeCommaLongitude,
  geoJsonFeature: formatAsGeoJsonFeature,
  geoJsonFeatureCollection: PointParameter.formatValueForUrl
};

function formatAsLongitudeCommaLatitude(value) {
  const longitude = CesiumMath.toDegrees(value.longitude);
  const latitude = CesiumMath.toDegrees(value.latitude);
  return `${longitude},${latitude}`;
}

function formatAsLatitudeCommaLongitude(value) {
  const longitude = CesiumMath.toDegrees(value.longitude);
  const latitude = CesiumMath.toDegrees(value.latitude);
  return `${latitude},${longitude}`;
}

function formatAsGeoJsonFeature(value) {
  return JSON.stringify(PointParameter.getGeoJsonFeature(value));
}

module.exports = PointParameter;