/**
 * Renders a scene with a camera
 * @param graphics GameLib.D3.Graphics
 * @param apiRenderTarget GameLib.D3.API.RenderTarget
 * @constructor
 */
GameLib.D3.RenderTarget = function (
    graphics,
    apiRenderTarget
) {

    this.graphics = graphics;
    this.graphics.isNotThreeThrow();

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

	if (apiRenderTarget instanceof GameLib.D3.RenderTarget) {
		return apiRenderTarget;
	}

    GameLib.D3.API.RenderTarget.call(
        this,
        apiRenderTarget.id,
        apiRenderTarget.name,
        apiRenderTarget.width,
        apiRenderTarget.height,
        apiRenderTarget.stencilBuffer,
        apiRenderTarget.texture
    );

    GameLib.Component.call(
        this,
        GameLib.Component.COMPONENT_RENDER_TARGET,
        {
            'texture' : GameLib.D3.Texture
        }
    );
};

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

/**
 * Creates a Render Target instance
 * @returns {*}
 */
GameLib.D3.RenderTarget.prototype.createInstance = function() {

    if (GameLib.Utils.UndefinedOrNull(this.texture)) {
        throw new Error('no texture');
    }

    if (GameLib.Utils.UndefinedOrNull(this.texture.instance)) {
        throw new Error('no texture instance');
    }

    this.instance = new THREE.WebGLRenderTarget(
        this.width,
        this.height,
        {
            stencilBuffer : this.stencilBuffer
        }
    );

    this.instance.texture = this.texture.instance;

    GameLib.Component.prototype.createInstance.call(this);
};

/**
 * updates instance
 */
GameLib.D3.RenderTarget.prototype.updateInstance = function() {

    if (this.instance) {
        this.instance.setSize(this.width, this.height);
        this.instance.stencilBuffer = this.stencilBuffer;
        if (this.texture && this.texture.loaded) {
            this.instance.texture = this.texture.instance;
            this.instance.texture.needsUpdate = true;
        } else {
            this.instance.texture = null;
        }
    } else {
        try {
            this.createInstance();
            this.loaded = true;
        } catch (error) {
            console.error(error);
        }
    }
};

/**
 * Render Target to API Render Target
 * @returns {GameLib.D3.API.RenderTarget}
 */
GameLib.D3.RenderTarget.prototype.toApiObject = function() {

    var apiRenderTarget = new GameLib.D3.API.RenderTarget(
        this.id,
        this.name,
        this.width,
        this.height,
        this.stencilBuffer,
        GameLib.Utils.IdOrNull(this.texture),
        GameLib.Utils.IdOrNull(this.parentEntity)
    );

    return apiRenderTarget;
};

/**
 *
 * @param graphics
 * @param objectComponent
 * @returns {GameLib.D3.RenderTarget}
 * @constructor
 */
GameLib.D3.RenderTarget.FromObject = function(graphics, objectComponent) {

    var apiRenderTarget = GameLib.D3.API.RenderTarget.FromObject(objectComponent);

    return new GameLib.D3.RenderTarget(
        graphics,
        apiRenderTarget
    );
};