OS.js

var OS = {

    /**
    * @property {boolean} desktop - Is running on a desktop?
    * @default
    */
    desktop: false,

    /**
    * @property {boolean} webApp - Set to true if running as a WebApp, i.e. within a WebView
    * @default
    */
    webApp: false,

    /**
    * @property {boolean} iOS - Is running on iOS?
    * @default
    */
    iOS: false,

    /**
    * @property {number} iOSVersion - If running in iOS this will contain the major version number.
    * @default
    */
    iOSVersion: 0,

    /**
    * @property {boolean} iPhone - Is running on iPhone?
    * @default
    */
    iPhone: false,

    /**
    * @property {boolean} iPad - Is running on iPad?
    * @default
    */
    iPad: false,

    /**
    * @property {boolean} cocoonJS - Is the game running under CocoonJS?
    * @default
    */
    cocoonJS: false,
    
    /**
    * @property {boolean} cocoonJSApp - Is this game running with CocoonJS.App?
    * @default
    */
    cocoonJSApp: false,
    
    /**
    * @property {boolean} cordova - Is the game running under Apache Cordova?
    * @default
    */
    cordova: false,
    
    /**
    * @property {boolean} node - Is the game running under Node.js?
    * @default
    */
    node: false,
    
    /**
    * @property {boolean} nodeWebkit - Is the game running under Node-Webkit?
    * @default
    */
    nodeWebkit: false,
    
    /**
    * @property {boolean} electron - Is the game running under GitHub Electron?
    * @default
    */
    electron: false,
    
    /**
    * @property {boolean} ejecta - Is the game running under Ejecta?
    * @default
    */
    ejecta: false,

    /**
    * @property {boolean} crosswalk - Is the game running under the Intel Crosswalk XDK?
    * @default
    */
    crosswalk: false,

    /**
    * @property {boolean} android - Is running on android?
    * @default
    */
    android: false,

    /**
    * @property {boolean} chromeOS - Is running on chromeOS?
    * @default
    */
    chromeOS: false,

    /**
    * @property {boolean} linux - Is running on linux?
    * @default
    */
    linux: false,

    /**
    * @property {boolean} macOS - Is running on macOS?
    * @default
    */
    macOS: false,

    /**
    * @property {boolean} windows - Is running on windows?
    * @default
    */
    windows: false,

    /**
    * @property {boolean} windowsPhone - Is running on a Windows Phone?
    * @default
    */
    windowsPhone: false,

    /**
    * @property {boolean} vita - Is running on a PlayStation Vita?
    * @default
    */
    vita: false,

    /**
    * @property {boolean} kindle - Is running on an Amazon Kindle?
    * @default
    */
    kindle: false,

    /**
    * @property {number} pixelRatio - PixelRatio of the host device?
    * @default
    */
    pixelRatio: 1

};

function init ()
{
    var ua = navigator.userAgent;

    if (/Windows/.test(ua))
    {
        OS.windows = true;
    }
    else if (/Mac OS/.test(ua))
    {
        OS.macOS = true;
    }
    else if (/Linux/.test(ua))
    {
        OS.linux = true;
    }
    else if (/Android/.test(ua))
    {
        OS.android = true;
    }
    else if (/iP[ao]d|iPhone/i.test(ua))
    {
        OS.iOS = true;
        (navigator.appVersion).match(/OS (\d+)/);
        OS.iOSVersion = parseInt(RegExp.$1, 10);
    }
    else if (/Kindle/.test(ua) || (/\bKF[A-Z][A-Z]+/).test(ua) || (/Silk.*Mobile Safari/).test(ua))
    {
        OS.kindle = true;

        // This will NOT detect early generations of Kindle Fire, I think there is no reliable way...
        // E.g. "Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_6_3; en-us; Silk/1.1.0-80) AppleWebKit/533.16 (KHTML, like Gecko) Version/5.0 Safari/533.16 Silk-Accelerated=true"
    }
    else if (/CrOS/.test(ua))
    {
        OS.chromeOS = true;
    }
    else if ((/Playstation Vita/).test(ua))
    {
        OS.vita = true;
    }

    if (/Windows Phone/i.test(ua) || (/IEMobile/i).test(ua))
    {
        OS.android = false;
        OS.iOS = false;
        OS.macOS = false;
        OS.windows = true;
        OS.windowsPhone = true;
    }

    var silk = (/Silk/).test(ua);

    if (OS.windows || OS.macOS || (OS.linux && !silk) || OS.chromeOS)
    {
        OS.desktop = true;
    }

    //  Windows Phone / Table reset
    if (OS.windowsPhone || ((/Windows NT/i.test(ua)) && (/Touch/i.test(ua))))
    {
        OS.desktop = false;
    }

    //  WebApp mode in iOS
    if (navigator.standalone)
    {
        OS.webApp = true;
    }
    
    if (window.cordova !== undefined)
    {
        OS.cordova = true;
    }
    
    if ((typeof process !== 'undefined') && (typeof process.versions.node !== 'undefined'))
    {
        OS.node = true;
    }
    
    if (OS.node && typeof process.versions === 'object')
    {
        OS.nodeWebkit = !!process.versions['node-webkit'];
        
        OS.electron = !!process.versions.electron;
    }
    
    if (navigator.isCocoonJS)
    {
        OS.cocoonJS = true;

        try
        {
            OS.cocoonJSApp = (typeof CocoonJS !== 'undefined');
        }
        catch (error)
        {
            OS.cocoonJSApp = false;
        }
    }

    if (window.ejecta !== undefined)
    {
        OS.ejecta = true;
    }

    if ((/Crosswalk/).test(ua))
    {
        OS.crosswalk = true;
    }

    OS.iPhone = ua.toLowerCase().indexOf('iphone') !== -1;
    OS.iPad = ua.toLowerCase().indexOf('ipad') !== -1;

    OS.pixelRatio = window['devicePixelRatio'] || 1;

    return OS;
}

module.exports = init();