// Style switcher code from http://www.alistapart.com/stories/alternate/

function setActiveStyleSheet(title) {
  var i, a, main;

  for (i=0; (a = document.getElementsByTagName("link")[i]); i++) {
    if (a.getAttribute("rel") &&
        a.getAttribute("rel").indexOf("style") != -1 &&
        a.getAttribute("title")) {
      a.disabled = true;
      if(a.getAttribute("title") == title) a.disabled = false;
    }
  }
}

function getActiveStyleSheet() {
  var i, a;
  for (i=0; (a = document.getElementsByTagName("link")[i]); i++) {
    if (a.getAttribute("rel") &&
        a.getAttribute("rel").indexOf("style") != -1 &&
        a.getAttribute("title") &&
        !a.disabled
        ) return a.getAttribute("title");
  }
  return null;
}

function getPreferredStyleSheet() {
  var i, a;
  for (i=0; (a = document.getElementsByTagName("link")[i]); i++) {
    if (a.getAttribute("rel") &&
        a.getAttribute("rel").indexOf("style") != -1 &&
        a.getAttribute("rel").indexOf("alt") == -1 &&
        a.getAttribute("title")
        ) return a.getAttribute("title");
  }
  return 'nancy';
}

function createCookie(name,value,days) {
  if (days) {
    var date = new Date();
    date.setTime(date.getTime()+(days*24*60*60*1000));
    var expires = "; expires="+date.toGMTString();
  }
  else expires = "";
  document.cookie = name+"="+value+expires+"; path=/";
}

function readCookie(name) {
  var nameEQ = name + "=";
  var ca = document.cookie.split(';');
  for(var i=0;i < ca.length;i++) {
    var c = ca[i];
    while (c.charAt(0)==' ') c = c.substring(1,c.length);
    if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
  }
  return null;
}

function switch_addLoadEvent(func) {
    var oldonload = window.onload;
    if (typeof window.onload != 'function') {
        window.onload = func;
    } else {
        window.onload = function() {
            oldonload();
            func();
        }
    }
}

function switch_cookie() {
  var cookie = readCookie("style");
  var title = cookie ? cookie : getPreferredStyleSheet();
  setActiveStyleSheet(title);

    // Requires reload to enforce Imperia login
    if (typeof need_reload != 'undefined' && need_reload == 'login') {
        location.href = location.href + '?imperiaLogin=true';
    }
}

switch_addLoadEvent(switch_cookie);

/*
window.onload = function(e) {
  var cookie = readCookie("style");
  var title = cookie ? cookie : getPreferredStyleSheet();
  setActiveStyleSheet(title);

    // Requires reload to enforce Imperia login
    if (typeof need_reload != 'undefined' && need_reload == 'login') {
        location.href = location.href + '?imperiaLogin=true';
    }
}
*/

window.onunload = function(e) {
  var title = getActiveStyleSheet();
  createCookie("style", title, 365);
}

var cookie = readCookie("style");
var title = cookie ? cookie : getPreferredStyleSheet();
setActiveStyleSheet(title);