terriajs/lib/Map/Concept.js

Geospatial data visualization platform.

'use strict';

/*global require*/

var defineProperties = require('terriajs-cesium/Source/Core/defineProperties');
var knockout = require('terriajs-cesium/Source/ThirdParty/knockout');

/**
 * Represents the bare minimum required to display a concept in the NowViewing tab.
 *
 * @alias Concept
 * @constructor
 */
var Concept = function(name) {
    /**
     * Gets or sets the id of the concept item. By default this is the same as the name.
     * It is allowed to be different eg. for csv files with tersely-named columns.
     * @type {String}
     */
    this.id = name;

    /**
     * Gets or sets the name of the concept item.  This property is observable.
     * @type {String}
     */
    this.name = name;

    /**
     * Flag to say if this if this node is selectable.  This property is observable.
     * If your subclass can return true, it must define an isActive property and a toggleActive function.
     * @type {Boolean}
     */
    this.isSelectable = undefined;

    /**
     * Gets or sets the items contained in this concept.  This property is observable.
     * Only used if the concept's hasChildren can return true.
     * @type {AbsConcept[]}
     */
    this.items = undefined;

    /**
     * Gets or sets a value indicating whether this concept item is currently open.  When an
     * item is open, its child items (if any) are visible.  This property is observable.
     * Only used if the concept's hasChildren can return true.
     * @type {Boolean}
     */
    this.isOpen = undefined;

    /**
     * Gets or sets a value indicating whether this concept is currently active.
     * Only used if the concept's isSelectable is true.
     * @type {Boolean}
     */
    this.isActive = undefined;  // A better name would be isSelected, since it can only be true if isSelectable. But isActive is used by the knockout view.

    /**
     * Gets or sets a value indicating whether this concept is visible. Defaults to true.
     * @type {Boolean}
     */
    this.isVisible = true;

    /**
     * String describing the color of this node, if applicable.  This property is observable.
     * @type {String}
     */
    this.color = undefined;

    knockout.track(this, ['name', 'isSelectable', 'isVisible', 'color']);
};

defineProperties(Concept.prototype, {
    /**
     * Gets a value indicating whether this item has child items.
     * If your subclass can return true, it must also define isOpen & items properties, and a toggleOpen function.
     * @type {Boolean}
     */
    hasChildren : {
        get : function() {
            return this.items && this.items.some(function(concept) {return concept.isVisible;});
        }
    }
});

/**
 * Toggles the {@link Concept#isOpen} property.  If this item's list of children is open,
 * calling this method will close it.  If the list is closed, calling this method will open it.
 */
Concept.prototype.toggleOpen = function() {
    this.isOpen = !this.isOpen;
};

/**
 * Toggles the {@link Concept#isActive} property.
 */
Concept.prototype.toggleActive = function() {
    this.isActive = !this.isActive;
};

module.exports = Concept;