/**
 * R3.D3.Texture.Cube
 * @param graphics
 * @param apiTextureCube
 * @constructor
 */
R3.D3.Texture.Cube = function(
    graphics,
    apiTextureCube
) {
    this.graphics = graphics;
    this.graphics.isNotThreeThrow();

    if (R3.Utils.UndefinedOrNull(apiTextureCube)) {
        apiTextureCube = {
            textureType : R3.D3.API.Texture.TEXTURE_TYPE_CUBE
        };
    }

    R3.D3.API.Texture.Cube.call(
        this,
        apiTextureCube,
        apiTextureCube.images
    );

    this.images = this.images.map(
        function(image) {
            if (image instanceof R3.API.Image) {
                return new R3.Image(image);
            } else {
                return image;
            }
        }
    );

    R3.D3.Texture.call(
        this,
        this.graphics,
        this
    );

};

R3.D3.Texture.Cube.prototype = Object.create(R3.D3.Texture.prototype);
R3.D3.Texture.Cube.prototype.constructor = R3.D3.Texture.Cube;

/**
 * Returns all image instances, or null if one of the images are not loaded
 */
R3.D3.Texture.Cube.prototype.getImageInstances = function() {

    return this.images.reduce(
        function(result, image) {

            /**
             * If we have a null result return early
             */

            if (result === null) {
                return result;
            }

            if (R3.Utils.UndefinedOrNull(image.instance)) {
                result = null;
            } else {
                result.push(image.instance);
            }

            return result;

        },
        []
    );
};

/**
 * Creates an instance of our texture object
 * @returns {*}
 */
R3.D3.Texture.Cube.prototype.createInstance = function() {

    var imageInstances = this.getImageInstances();

    if (!imageInstances) {
        console.warn('cube texture not ready');
        return;
    }

    this.instance = new THREE.CubeTexture(imageInstances);

    R3.D3.Texture.prototype.createInstance.call(this);
};

/**
 * Updates the instance with the current state
 */
R3.D3.Texture.Cube.prototype.updateInstance = function(property) {

    if (property === 'images') {


        var imageInstances = this.getImageInstances();

        if (imageInstances) {
            console.log('updating cube texture image instances');
            this.image = imageInstances;
        }

        this.emit(
            R3.Event.TEXTURE_INSTANCE_UPDATED,
            {
                texture : this
            }
        );

        return;
    }

    R3.D3.Texture.prototype.updateInstance.call(this, property);
};

/**
 * Converts a R3.D3.Texture.Cube to a R3.D3.API.Texture.Cube
 * @returns {R3.D3.API.Texture.Cube}
 */
R3.D3.Texture.Cube.prototype.toApiObject = function() {

    var apiTexture = R3.D3.Texture.prototype.toApiObject.call(this);

    var apiTextureCube = new R3.D3.API.Texture.Cube(
        apiTexture,
        this.images.map(
            function(image) {
                return R3.Utils.IdOrNull(image);
            }
        )
    );

    return apiTextureCube;
};