/***********************************************************************************************
Script to swap between stylesheets
Written by Mark Wilton-Jones, 05/12/2002. v2.2.1 updated 14/03/2006 for dynamic stylesheets
************************************************************************************************

Please see http://www.howtocreate.co.uk/jslibs/ for details and a demo of this script
Please see http://www.howtocreate.co.uk/jslibs/termsOfUse.html for terms of use

To set up the page in the first place:

Inbetween the <head> tags, put:

<script src="PATH TO SCRIPT/swapstyle.js" type="text/javascript" language="javascript1.2"></script>

Also between the head tags, put your stylesheets, best done as external links, but you can use
<style ...> tags as well.

Stylesheets cannot be switched if they have no title attribute and will be used at all times:

<link rel="stylesheet" type="text/css" href="all.css">

Stylesheets will be on by default if they have a title attribute and their rel attribute is set to 'stylesheet'.
Most browsers will only allow one of these to be defined (or several sharing the same title):

<link rel="stylesheet" type="text/css" href="default.css" title="Default">

Stylesheets will be off by default if they have a title attribute and their rel attribute is set to 'alternate stylesheet':

<link rel="alternate stylesheet" type="text/css" href="contrast.css" title="High Contrast">
<link rel="alternate stylesheet" type="text/css" href="bigFont.css" title="Big Font">

To swap between stylesheets:

changeStyle();                           //switches off all stylesheets that have title attributes
changeStyle('Default');                  //switches off all stylesheets that have title attributes that do not match 'Default'
changeStyle('High Contrast');            //switches off all stylesheets that have title attributes that do not match 'High Contrast'
changeStyle('Big Font');                 //switches off all stylesheets that have title attributes that do not match 'Big Font'
changeStyle('High Contrast','Big Font'); //switches off all stylesheets that have title attributes that do not match 'High Contrast' or 'Big Font'

Opera 7+ and Mozilla also allow users to switch between stylesheets using the view menu (only one at a time though ...)

To make the script remember the user's choice of stylesheets, for example to use on more than one page or if they reload
- includes stylesheets chosen using the view menu in Gecko - it will only attempt to store a cookie if they actually
changed something:

In these examples, I call the cookie used to store the choice 'styleTestStore'. You could use any name you like.

To remember only until the browser window is closed:

<body onload="useStyleAgain('styleTestStore');" onunload="rememberStyle('styleTestStore');">

To remember for 10 days (for example):

<body onload="useStyleAgain('styleTestStore');" onunload="rememberStyle('styleTestStore',10);">

If you are going to provide users with a mechanism to change stylesheets, you may want to check
if the browser will allow you to change stylsheets first. Use:

if( document.styleSheets || ( window.opera && document.childNodes ) || ( window.ScriptEngine && ScriptEngine().indexOf('InScript') + 1 && document.createElement ) ) {
document.write('Something that allows them to choose stylesheets');
}

It's not perfect, because it will also appear in ICEbrowser, which makes a mess when it tries to
change to an alternate stylesheet. If you want, you can use
if( ( document.styleSheets || ( window.opera && document.childNodes ) || ( window.ScriptEngine && ScriptEngine().indexOf('InScript') + 1 && document.createElement ) ) && !navigator.__ice_version ) {
but you should then update that if ICE is updated to make it work properly.
________________________________________________________________________________________________*/

function getAllSheets() {
	if( !window.ScriptEngine && navigator.__ice_version ) { return document.styleSheets; }
	if( document.getElementsByTagName ) { var Lt = document.getElementsByTagName('link'), St = document.getElementsByTagName('style');
	} else if( document.styleSheets && document.all ) { var Lt = document.all.tags('LINK'), St = document.all.tags('STYLE');
	} else { return []; } for( var x = 0, os = []; Lt[x]; x++ ) {
		var rel = Lt[x].rel ? Lt[x].rel : Lt[x].getAttribute ? Lt[x].getAttribute('rel') : '';
		if( typeof( rel ) == 'string' && rel.toLowerCase().indexOf('style') + 1 ) { os[os.length] = Lt[x]; }
	} for( var x = 0; St[x]; x++ ) { os[os.length] = St[x]; } return os;
}
function changeStyle() {
	window.userHasChosen = window.MWJss;
	for(var x = 0, ss = getAllSheets(); ss[x]; x++) {
		if(ss[x].title)
		{
			ss[x].disabled = true;
		}
		for(var y = 0; y < arguments.length; y++)
		{
			if(ss[x].title == arguments[y])
			{
				ss[x].disabled = false;
			}
		}
//		rememberStyle('styleTestStore');
//		for(var z = 0; z < arguments.length; z++) {
//			if (arguments[z] == "style")
//			{
//				document.getElementById('textControlText').style.display = 'none'
//				document.getElementById('textControlImage').style.display = 'block'
//			}
//			if (arguments[z] == "text")
//			{
//				document.getElementById('textControlImage').style.display = 'none'
//				document.getElementById('textControlText').style.display = 'block'
//			}
//		}
	}
}

function rememberStyle( cookieName, cookieLife ) {
	for( var viewUsed = false, ss = getAllSheets(), x = 0; window.MWJss && MWJss[x] && ss[x]; x++ ) { if( ss[x].disabled != MWJss[x] ) { viewUsed = true; break; } }
	if( !window.userHasChosen && !viewUsed ) { return; }
	for( var x = 0, outLine = '', doneYet = []; ss[x]; x++ ) {
		if( ss[x].title && ss[x].disabled == false && !doneYet[ss[x].title] ) { doneYet[ss[x].title] = true; outLine += ( outLine ? ' MWJ ' : '' ) + escape( ss[x].title ); } }
	if( ss.length ) { document.cookie = escape( cookieName ) + '=' + escape( outLine ) + ( cookieLife ? ';expires=' + new Date( ( new Date() ).getTime() + ( cookieLife * 86400000 ) ).toGMTString() : '' ) + ';path=/'; }
}

function setCookie(cookieName,cookieValue,nDays) {
 var today = new Date();
 var expire = new Date();
 if (nDays==null || nDays==0) nDays=1;
 expire.setTime(today.getTime() + 3600000*24*nDays);
 document.cookie = cookieName+"="+escape(cookieValue)
                 + ";expires="+expire.toGMTString()
                 + ";path=/";
}

function useStyleAgain( cookieName, currentSheet ) {
	for( var x = 0; x < document.cookie.split( "; " ).length; x++ ) {
		var oneCookie = document.cookie.split( "; " )[x].split( "=" );
		if( oneCookie[0] == escape( cookieName ) ) {
			var styleStrings = unescape( oneCookie[1] ).split( " MWJ " );
			for (var x = 0; x < styleStrings.length; x++) {
				if (styleStrings[x] == "defaultSize") {
					window.size = "defaultSize";
				}
				if (styleStrings[x] == "large") {
					window.size = "large";
				}
				if (styleStrings[x] == "xLarge") {
					window.size = "xLarge";
				}
				if (styleStrings[x] == "defaultColour") {
					window.colour = "defaultColour";
				}
				if (styleStrings[x] == "contrast") {
					window.colour = "contrast";
				}
				if (styleStrings[x] == "highContrast") {
					window.colour = "highContrast";
				}
			}
			for( var y = 0, funcStr = ''; styleStrings[y]; y++ ) { funcStr += ( y ? ',' : '' ) + 'unescape( styleStrings[' + y + '] )'; }
			eval( 'changeStyle(' + funcStr + ', currentSheet);' ); break;
		} } window.MWJss = []; for( var ss = getAllSheets(), x = 0; ss[x]; x++ ) { MWJss[x] = ss[x].disabled; }
}