/**
 * System takes care of updating all the entities (based on their component data)
 * @param apiSystem GameLib.API.System
 * @constructor
 */
GameLib.System.GUI = function(
    apiSystem
) {
    GameLib.System.call(
        this,
        apiSystem
    );

    this.guis = [];

    this.buildGUISubscription = null;

    this.meshDeletedSubscription = null;

    this.meshSelectedSubscription = null;

    this.meshDeselectedSubscription = null;

    this.newEntitySubscription = null;

};

GameLib.System.GUI.prototype = Object.create(GameLib.System.prototype);
GameLib.System.GUI.prototype.constructor = GameLib.System.GUI;

GameLib.System.GUI.prototype.start = function() {

    this.guis = GameLib.EntityManager.Instance.queryComponents(GameLib.GUI);

    this.guis.map(function(gui){
		gui.domElement.instance.parentElement.appendChild(gui.instance.domElement);
	});

    this.buildGUISubscription = this.subscribe(
        GameLib.Event.BUILD_GUI,
        this.buildGUI
    );

    this.meshDeletedSubscription = this.subscribe(
        GameLib.Event.MESH_DELETED,
        this.meshDeleted
    );

    this.meshSelectedSubscription = this.subscribe(
        GameLib.Event.MESH_SELECTED,
        this.meshSelected
    );

    this.meshDeselectedSubscription = this.subscribe(
        GameLib.Event.MESH_DESELECTED,
        this.meshDeslected
    );

    this.newEntitySubscription = this.subscribe(
        GameLib.Event.NEW_ENTITY,
        this.newEntity
    )
};

GameLib.System.GUI.prototype.buildGUI = function(data) {



    this.guis.map(function(gui){
        gui.objects = [];

        if (
            data.components &&
            data.components.length > 0
        ) {
            gui.objects = data.components;
        }

        gui.build(GameLib.EntityManager.Instance);
    });

};

GameLib.System.GUI.prototype.meshDeleted = function(data) {

};

GameLib.System.GUI.prototype.meshSelected = function(data) {

};

GameLib.System.GUI.prototype.meshDeslected = function(data) {

};

GameLib.System.GUI.prototype.newEntity = function(data) {

};

GameLib.System.GUI.prototype.stop = function() {

    this.guis.map(function(gui){
		gui.domElement.instance.parentElement.removeChild(gui.instance.domElement);
	});

    this.buildGUISubscription.remove();

    this.meshDeletedSubscription.remove();

    this.meshSelectedSubscription.remove();

    this.meshDeselectedSubscription.remove();

    this.newEntitySubscription.remove();

    this.guis = [];
};