let core = require('../../core');

/**
 * Prepare uploads elements to the GPU. The CanvasRenderer version of prepare
 * provides the same APIs as the WebGL version, but doesn't do anything.
 * @class
 * @memberof PIXI
 * @param renderer {PIXI.CanvasRenderer} A reference to the current renderer
 */
class CanvasPrepare {
    constructor()
    {
    }

    /**
     * Stub method for upload.
     * @param {Function|PIXI.DisplayObject|PIXI.Container} item Either
     *        the container or display object to search for items to upload or
     *        the callback function, if items have been added using `prepare.add`.
     * @param {Function} done When completed
     */
    upload(displayObject, done)
    {
        if (typeof displayObject === 'function')
        {
            done = displayObject;
            displayObject = null;
        }
        done();
    }

    /**
     * Stub method for registering hooks.
     * @return {PIXI.CanvasPrepare} Instance of plugin for chaining.
     */
    register()
    {
        return this;
    }

    /**
     * Stub method for adding items.
     * @return {PIXI.CanvasPrepare} Instance of plugin for chaining.
     */
    add()
    {
        return this;
    }

    /**
     * Stub method for destroying plugin.
     */
    destroy()
    {
    }

}

module.exports = CanvasPrepare;

core.CanvasRenderer.registerPlugin('prepare', CanvasPrepare);