/**
 * Helpers for displaying outlines or making 'invisible' scene objects visible
 * @param graphics GameLib.D3.Graphics
 * @param apiHelper GameLib.D3.API.Helper
 * @constructor
 */
GameLib.D3.Helper = function Helper(
    graphics,
    apiHelper
) {
    this.graphics = graphics;
    this.graphics.isNotThreeThrow();

    if (GameLib.Utils.UndefinedOrNull(apiHelper)) {
        apiHelper = {};
    }

    GameLib.D3.API.Helper.call(
        this,
        apiHelper.id,
        apiHelper.name,
        apiHelper.helperType,
        apiHelper.object,
        apiHelper.parentEntity
    );

    this.instance = this.createInstance();
};

GameLib.D3.Helper.prototype = Object.create(GameLib.D3.API.Helper.prototype);
GameLib.D3.Helper.prototype.constructor = GameLib.D3.Helper;

/**
 * Helper types
 * @type {string}
 */
GameLib.D3.Helper.HELPER_TYPE_EDGES             = 'edges';
GameLib.D3.Helper.HELPER_TYPE_DIRECTIONAL_LIGHT = 'directional-light';
GameLib.D3.Helper.HELPER_TYPE_SPOT_LIGHT        = 'spot-light';
GameLib.D3.Helper.HELPER_TYPE_POINT_LIGHT       = 'point-light';
GameLib.D3.Helper.HELPER_TYPE_WIREFRAME         = 'wireframe';
GameLib.D3.Helper.HELPER_TYPE_SKELETON          = 'skeleton';


/**
 * Creates a helper instance
 * @param update
 */
GameLib.D3.Helper.prototype.createInstance = function(update) {

    var instance = null;

    if (update) {
        instance = this.instance;
    }

    if (this.helperType == GameLib.D3.Helper.HELPER_TYPE_EDGES) {
        instance = new THREE.WireframeHelper(this.object.instance, 0x007700);
    }

    if (this.helperType == GameLib.D3.Helper.HELPER_TYPE_DIRECTIONAL_LIGHT) {
        instance = new THREE.DirectionalLightHelper(this.object.instance);
    }

    if (this.helperType == GameLib.D3.Helper.HELPER_TYPE_POINT_LIGHT) {
        instance = new THREE.PointLightHelper(this.object.instance, 1);
    }

    if (this.helperType == GameLib.D3.Helper.HELPER_TYPE_SPOT_LIGHT) {
        instance = new THREE.SpotLightHelper(this.object.instance);
    }

    if (this.helperType == GameLib.D3.Helper.HELPER_TYPE_WIREFRAME) {
        instance = new THREE.WireframeHelper(this.object.instance, 0x007700);
    }

    if (this.helperType == GameLib.D3.Helper.HELPER_TYPE_SKELETON) {
        instance = new THREE.SkeletonHelper(this.object.instance);
    }

    if (!instance) {
        throw new Error('Unsupported helper type: ' + this.helperType);
    }

    return instance;
};

/**
 * Updates the instance with the current state
 */
GameLib.D3.Helper.prototype.updateInstance = function() {
    this.instance = this.createInstance(true);
};

/**
 * Converts a GameLib.D3.Helper to a new GameLib.D3.API.Helper
 * @returns {GameLib.D3.API.Helper}
 */
GameLib.D3.Helper.prototype.toApiHelper = function() {

    return new GameLib.D3.API.Helper(
        this.id,
        this.name,
        this.helperType,
        GameLib.Utils.IdOrNull(this.object),
        GameLib.Utils.IdOrNull(this.parentEntity)
    );

};

/**
 * Converts from an Object Helper to a GameLib.D3.Helper
 * @param graphics GameLib.D3.Graphics
 * @param objectHelper Object
 * @returns {GameLib.D3.Helper}
 * @constructor
 */
GameLib.D3.Helper.FromObjectHelper = function(graphics, objectHelper) {

    var apiHelper = GameLib.D3.API.Helper.FromObjectHelper(objectHelper);

    return new GameLib.D3.Helper(
        graphics,
        apiHelper
    );

};