/**
 * Renders a scene with a camera
 * @param graphics GameLib.GraphicsRuntime
 * @param apiPass GameLib.D3.API.Pass
 * @constructor
 */
GameLib.D3.Pass = function (
    graphics,
    apiPass
) {

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

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

	if (apiPass instanceof GameLib.D3.Pass) {
		return apiPass;
	}

    GameLib.D3.API.Pass.call(
        this,
        apiPass.id,
        apiPass.name,
        apiPass.passType,
        apiPass.camera,
        apiPass.scene,
        apiPass.renderToScreen,
        apiPass.parentEntity
    );

    GameLib.Component.call(
        this,
        {
            'camera' : GameLib.D3.Camera,
            'scene' : GameLib.D3.Scene
        }
    );
};

GameLib.D3.Pass.prototype = Object.create(GameLib.Component.prototype);
GameLib.D3.Pass.prototype.constructor = GameLib.D3.Pass;

GameLib.D3.Pass.PASS_TYPE_RENDER       = 0x1;
GameLib.D3.Pass.PASS_TYPE_COPY_SHADER  = 0x2;

/**
 * Create Pass instance
 * @returns {*}
 */
GameLib.D3.Pass.prototype.createInstance = function() {

    if (this.passType === GameLib.D3.Pass.PASS_TYPE_RENDER) {

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

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

        if (GameLib.Utils.UndefinedOrNull(THREE.RenderPass)) {
            throw new Error('no render pass library')
        }

        this.instance = new THREE.RenderPass(
            this.scene.instance,
            this.camera.instance
        );

    } else if (this.passType === GameLib.D3.Pass.PASS_TYPE_COPY_SHADER) {

        if (GameLib.Utils.UndefinedOrNull(THREE.CopyShader)) {
            throw new Error('no copyshader library')
        }

        this.instance = THREE.CopyShader;

    } else {
        console.warn('Render pass not supported yet: ' + this.passType);
        throw new Error('Render pass not supported yet: ' + this.passType);
    }

    this.instance.renderToScreen = this.renderToScreen;

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

};

/**
 * Update Pass instance
 */
GameLib.D3.Pass.prototype.updateInstance = function() {

    if (
        this.passType === GameLib.D3.Pass.PASS_TYPE_RENDER && !(this.instance instanceof THREE.RenderPass)){
        this.createInstance();
    }

    if (
        this.passType === GameLib.D3.Pass.PASS_TYPE_COPY_SHADER && !(this.instance instanceof THREE.CopyShader)){
        this.createInstance();
    }

    this.instance.renderToScreen = this.renderToScreen;

};

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

    var apiPass = new GameLib.D3.API.Pass(
        this.id,
        this.name,
        this.passType,
        GameLib.Utils.IdOrNull(this.camera),
        GameLib.Utils.IdOrNull(this.scene),
        this.renderToScreen,
        GameLib.Utils.IdOrNull(this.parentEntity)
    );

    return apiPass;
};

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

    var apiPass = GameLib.D3.API.Pass.FromObject(objectComponent);

    return new GameLib.D3.Pass(
        graphics,
        apiPass
    );
};