/*!
Intelligent auto-scrolling to hide the mobile device address bar
Optic Swerve, opticswerve.com
Documented at http://menacingcloud.com/?c=iPhoneAddressBar
*/

var bodyTag;
var executionTime = new Date().getTime(); // JavaScript execution time

// Document ready
//----------------
documentReady(function() {
	// Don't hide address bar after a distracting amount of time
	var readyTime = new Date().getTime()
	if((readyTime - executionTime) < 3000) hideAddressBar(true);

});

// Run specified function when document is ready (HTML5)
//------------------------------------------------------
function documentReady(readyFunction) {
	document.addEventListener('DOMContentLoaded', function() {
		document.removeEventListener('DOMContentLoaded', arguments.callee, false);
		readyFunction();

	}, false);

}

// Hide address bar on devices like the iPhone
//---------------------------------------------
function hideAddressBar(bPad) {
	// Big screen. Fixed chrome likely.
	if(screen.width > 980 || screen.height > 980) return;

	// Standalone (full screen webapp) mode
	if(window.navigator.standalone === true) return;

	// Page zoom or vertical scrollbars
	if(window.innerWidth !== document.documentElement.clientWidth) {
		// Sometimes one pixel too much. Compensate.
		if((window.innerWidth - 1) !== document.documentElement.clientWidth) return;

	}

	// Pad content if necessary.
	if(bPad === true && (document.documentElement.scrollHeight <= document.documentElement.clientHeight)) {
		// Extend body height to overflow and cause scrolling
		bodyTag = document.getElementsByTagName('body')[0];

		// Viewport height at fullscreen
		bodyTag.style.height = document.documentElement.clientWidth / screen.width * screen.height + 'px';

	}

	setTimeout(function() {
		// Already scrolled?
		if(window.pageYOffset !== 0) return;

		// Perform autoscroll
		window.scrollTo(0, 1);

		// Reset body height and scroll
		if(bodyTag !== undefined) bodyTag.style.height = window.innerHeight + 'px';
		window.scrollTo(0, 0);

	}, 1000);

}

// Quick address bar hide on devices like the iPhone
//---------------------------------------------------
function quickHideAddressBar() {
	setTimeout(function() {
		if(window.pageYOffset !== 0) return;
		window.scrollTo(0, window.pageYOffset + 1);

	}, 1000);

}