alpaca/dist/lib/respond/cross-domain/respond.proxy.js

Alpaca provides the easiest and fastest way to generate interactive forms for the web and mobile devices. It runs simply as HTML5 or more elaborately using Bootstrap, jQuery Mobile or jQuery UI. Alpaca uses Handlebars to process JSON schema and provide

/*! Respond.js: min/max-width media query polyfill. Remote proxy (c) Scott Jehl. MIT/GPLv2 Lic. j.mp/respondjs  */
(function(win, doc, undefined){
	var docElem			= doc.documentElement,
		proxyURL		= doc.getElementById("respond-proxy").href,
		redirectURL		= (doc.getElementById("respond-redirect") || location).href,
		baseElem		= doc.getElementsByTagName("base")[0],
		urls			= [],
		refNode;

	function encode(url){
		return win.encodeURIComponent(url);
	}

	 function fakejax( url, callback ){

		var iframe,
			AXO;
		
		// All hail Google http://j.mp/iKMI19
		// Behold, an iframe proxy without annoying clicky noises.
		if ( "ActiveXObject" in win ) {
			AXO = new ActiveXObject( "htmlfile" );
			AXO.open();
			AXO.write( '<iframe id="x"></iframe>' );
			AXO.close();
			iframe = AXO.getElementById( "x" );
		} else {
			iframe = doc.createElement( "iframe" );
			iframe.style.cssText = "position:absolute;top:-99em";
			docElem.insertBefore(iframe, docElem.firstElementChild || docElem.firstChild );
		}

		iframe.src = checkBaseURL(proxyURL) + "?url=" + encode(redirectURL) + "&css=" + encode(checkBaseURL(url));
		
		function checkFrameName() {
			var cssText;

			try {
				cssText = iframe.contentWindow.name;
			}
			catch (e) { }

			if (cssText) {
				// We've got what we need. Stop the iframe from loading further content.
				iframe.src = "about:blank";
				iframe.parentNode.removeChild(iframe);
				iframe = null;

			
				// Per http://j.mp/kn9EPh, not taking any chances. Flushing the ActiveXObject
				if (AXO) {
					AXO = null;

					if (win.CollectGarbage) {
						win.CollectGarbage();
					}
				}

				callback(cssText);
			}
			else{
				win.setTimeout(checkFrameName, 100);
			}
		}
		
		win.setTimeout(checkFrameName, 500);
	}

	function checkBaseURL(href) {
		if (baseElem && href.indexOf(baseElem.href) === -1) {
			bref = (/\/$/).test(baseElem.href) ? baseElem.href : (baseElem.href + "/");
			href = bref + href;
		}

		return href;
	}
	
	function checkRedirectURL() {
		// IE6 & IE7 don't build out absolute urls in <link /> attributes.
		// So respond.proxy.gif remains relative instead of http://example.com/respond.proxy.gif.
		// This trickery resolves that issue.
		if (~ !redirectURL.indexOf(location.host)) {

			var fakeLink = doc.createElement("div");

			fakeLink.innerHTML = '<a href="' + redirectURL + '"></a>';
			docElem.insertBefore(fakeLink, docElem.firstElementChild || docElem.firstChild );

			// Grab the parsed URL from that dummy object
			redirectURL = fakeLink.firstChild.href;

			// Clean up
			fakeLink.parentNode.removeChild(fakeLink);
			fakeLink = null;
		}
	}
	
	function buildUrls(){
		var links = doc.getElementsByTagName( "link" );
		
		for( var i = 0, linkl = links.length; i < linkl; i++ ){
			
			var thislink	= links[i],
				href		= links[i].href,
				extreg		= (/^([a-zA-Z:]*\/\/(www\.)?)/).test( href ),
				ext			= (baseElem && !extreg) || extreg;

			//make sure it's an external stylesheet
			if( thislink.rel.indexOf( "stylesheet" ) >= 0 && ext ){
				(function( link ){			
					fakejax( href, function( css ){
						link.styleSheet.rawCssText = css;
						respond.update();
					} );
				})( thislink );
			}	
		}

		
	}
	
	if( !respond.mediaQueriesSupported ){
		checkRedirectURL();
		buildUrls();
	}

})( window, document );