/**
 * @author alteredq / http://alteredqualia.com/
 * @author mr.doob / http://mrdoob.com/
 */

var Detector = {

    canvas: !!window.CanvasRenderingContext2D,
    webgl: (function () {

        try {

            var canvas = document.createElement('canvas');
            return !!( window.WebGLRenderingContext && ( canvas.getContext('webgl') || canvas.getContext('experimental-webgl') ) );

        } catch (e) {

            return false;

        }

    })(),
    workers: !!window.Worker,
    fileapi: window.File && window.FileReader && window.FileList && window.Blob,

    getWebGLErrorMessage: function () {

        var element = document.createElement('div');
        element.id = 'webgl-error-message';
        element.style.fontFamily = 'monospace';
        element.style.fontSize = '13px';
        element.style.fontWeight = 'normal';
        element.style.textAlign = 'center';
        element.style.background = '#fff';
        element.style.color = '#000';
        element.style.padding = '1.5em';
        element.style.width = '400px';
        element.style.margin = '5em auto 0';

        if (!this.webgl) {

            element.innerHTML = window.WebGLRenderingContext ? [
                'Your graphics card does not seem to support <a href="http://khronos.org/webgl/wiki/Getting_a_WebGL_Implementation" style="color:#000">WebGL</a>.<br />',
                'Find out how to get it <a href="http://get.webgl.org/" style="color:#000">here</a>.'
            ].join('\n') : [
                'Your browser does not seem to support <a href="http://khronos.org/webgl/wiki/Getting_a_WebGL_Implementation" style="color:#000">WebGL</a>.<br/>',
                'Find out how to get it <a href="http://get.webgl.org/" style="color:#000">here</a>.'
            ].join('\n');

        }

        return element;

    },

    addGetWebGLMessage: function (parameters) {

        var parent, id, element;

        parameters = parameters || {};

        parent = parameters.parent !== undefined ? parameters.parent : document.body;
        id = parameters.id !== undefined ? parameters.id : 'oldie';

        element = Detector.getWebGLErrorMessage();
        element.id = id;

        parent.appendChild(element);

    }

};

// browserify support
if (typeof module === 'object') {

    module.exports = Detector;

}