//Style Sheet Switcher version 1.1 Oct 10th, 2006

//Author: Dynamic Drive: http://www.dynamicdrive.com

//Usage terms: http://www.dynamicdrive.com/notice.htm



var manual_or_random="manual" //"manual" or "random"

var randomsetting="3 days" //"eachtime", "sessiononly", or "x days (replace x with desired integer)". Only applicable if mode is random.



//////No need to edit beyond here//////////////



function getCookie(Name) { 

var re=new RegExp(Name+"=[^;]+", "i"); //construct RE to search for target name/value pair

if (document.cookie.match(re)) //if cookie found

return document.cookie.match(re)[0].split("=")[1] //return its value

return null

}



function setCookie(name, value, days) {

var expireDate = new Date()

//set "expstring" to either future or past date, to set or delete cookie, respectively

var expstring=(typeof days!="undefined")? expireDate.setDate(expireDate.getDate()+parseInt(days)) : expireDate.setDate(expireDate.getDate()-5)

document.cookie = name+"="+value+"; expires="+expireDate.toGMTString()+"; path=/";

}



function deleteCookie(name){

setCookie(name, "moot")

}





function setStylesheet(title, randomize){ //Main stylesheet switcher function. Second parameter if defined causes a random alternate stylesheet (including none) to be enabled

var i, cacheobj, altsheets=[""]

for(i=0; (cacheobj=document.getElementsByTagName("link")[i]); i++) {

if(cacheobj.getAttribute("rel").toLowerCase()=="alternate stylesheet" && cacheobj.getAttribute("title")) { //if this is an alternate stylesheet with title

cacheobj.disabled = true

altsheets.push(cacheobj) //store reference to alt stylesheets inside array

if(cacheobj.getAttribute("title") == title) //enable alternate stylesheet with title that matches parameter

cacheobj.disabled = false //enable chosen style sheet

}

}

if (typeof randomize!="undefined"){ //if second paramter is defined, randomly enable an alt style sheet (includes non)

var randomnumber=Math.floor(Math.random()*altsheets.length)

altsheets[randomnumber].disabled=false

}

return (typeof randomize!="undefined" && altsheets[randomnumber]!="")? altsheets[randomnumber].getAttribute("title") : "" //if in "random" mode, return "title" of randomly enabled alt stylesheet

}



function chooseStyle(styletitle, days){ //Interface function to switch style sheets plus save "title" attr of selected stylesheet to cookie

if (document.getElementById){

setStylesheet(styletitle)

setCookie("mysheet", styletitle, days)

}

}



function indicateSelected(element){ //Optional function that shows which style sheet is currently selected within group of radio buttons or select menu

if (selectedtitle!=null && (element.type==undefined || element.type=="select-one")){ //if element is a radio button or select menu

var element=(element.type=="select-one") ? element.options : element

for (var i=0; i<element.length; i++){

if (element[i].value==selectedtitle){ //if match found between form element value and cookie value

if (element[i].tagName=="OPTION") //if this is a select menu

element[i].selected=true

else //else if it's a radio button

element[i].checked=true

break

}

}

}

}



if (manual_or_random=="manual"){ //IF MANUAL MODE

var selectedtitle=getCookie("mysheet")

if (document.getElementById && selectedtitle!=null) //load user chosen style sheet from cookie if there is one stored

setStylesheet(selectedtitle)

}

else if (manual_or_random=="random"){ //IF AUTO RANDOM MODE

if (randomsetting=="eachtime")

setStylesheet("", "random")

else if (randomsetting=="sessiononly"){ //if "sessiononly" setting

if (getCookie("mysheet_s")==null) //if "mysheet_s" session cookie is empty

document.cookie="mysheet_s="+setStylesheet("", "random")+"; path=/" //activate random alt stylesheet while remembering its "title" value

else

setStylesheet(getCookie("mysheet_s")) //just activate random alt stylesheet stored in cookie

}

else if (randomsetting.search(/^[1-9]+ days/i)!=-1){ //if "x days" setting

if (getCookie("mysheet_r")==null || parseInt(getCookie("mysheet_r_days"))!=parseInt(randomsetting)){ //if "mysheet_r" cookie is empty or admin has changed number of days to persist in "x days" variable

setCookie("mysheet_r", setStylesheet("", "random"), parseInt(randomsetting)) //activate random alt stylesheet while remembering its "title" value

setCookie("mysheet_r_days", randomsetting, parseInt(randomsetting)) //Also remember the number of days to persist per the "x days" variable

}

else

setStylesheet(getCookie("mysheet_r")) //just activate random alt stylesheet stored in cookie

} 

}
