/* Dynamic Layout by Filipe Fortes 
 * http://fortes.com/projects/dynamiclayout
 * 
 * Original inspiration from the Man in Blue
 * http://www.themaninblue.com/writing/perspective/2006/01/19/
 */

if (typeof dynamicLayout == 'undefined' || ! dynamicLayout)
{
    var dynamicLayout = {};
}

dynamicLayout.sizes = Array(750,1000);
dynamicLayout.prefix = 'i-';
dynamicLayout.styleMatch = RegExp(dynamicLayout.prefix + '(min|unknown|[0-9]+)', 'ig');
dynamicLayout.body = document.body;
dynamicLayout.previousWidth = null;

// Get the window width
// dynamicLayout code based on http://code.google.com/p/doctype/wiki/ArticleViewportSize
dynamicLayout.getBrowserWidth = function()
{
    if (window.innerWidth)
        return window.innerWidth;
    else if (document.documentElement && document.documentElement.clientWidth != 0)
        return document.documentElement.clientWidth;
    else if (document.body)
        return document.body.clientWidth;

    return 0;
};

dynamicLayout.getStyleName = function()
{
    var w = dynamicLayout.getBrowserWidth();
    if (w == dynamicLayout.previousWidth)
    {
        // short circuit, no change
        return null;
    }
    
    dynamicLayout.previousWidth = w;

    if (w != 0)
    {
        for(var i = 0; i < dynamicLayout.sizes.length; i++) 
        {
            s = dynamicLayout.sizes[i];
            if (w >= s)
            {
                return dynamicLayout.prefix + s;
            }
        }
        return dynamicLayout.prefix + 'min';
    }
    else
    {
        // Zero width is no good, ignore
        dynamicLayout.previousWidth = null;
    }
}

dynamicLayout.updateStyle = function()
{
    var newStyleName = dynamicLayout.getStyleName();
    if (newStyleName == null) return;
    var newClass = dynamicLayout.body.className.replace(dynamicLayout.styleMatch, '');
    dynamicLayout.body.className = newClass + ' ' + newStyleName;
};

dynamicLayout.init = function()
{
    var resizeHandler = true;

    // Find custom sizes set via querystring
    scripts = document.getElementsByTagName('script');

    for (var i = 0; i < scripts.length; i++)
    {
        s = scripts[i];
        if ((s.src) && (s.src.match(/dynamiclayout(-[0-9]\.[0-9])?(\.min)?\.js/)))
        {
            var sizes = (s.src.match(/sizes=([0-9]|,)+/));
            if (sizes)
            {
                sizes = sizes[0].split('=')[1].split(',');
                // Sort into descending order
                sizes.sort(function s(a,b) { return parseInt(b) - parseInt(a); });
                dynamicLayout.sizes = sizes;
            }

            resizeHandler = (s.src.match(/noresize/) == null);
            break;
        }
    }

    if (resizeHandler)
    {
        // Attach the resize handler
        if (typeof window.addEventListener != 'undefined')
            window.addEventListener('resize', dynamicLayout.updateStyle, false);
        else
            window.attachEvent('onresize', dynamicLayout.updateStyle);
    }

    dynamicLayout.updateStyle();
};

dynamicLayout.init();

function showlayer(layer){
	var myLayer=document.getElementById(layer).style.display;
	if(myLayer=="block"){
		document.getElementById(layer).style.display="none";
	} else { 
		document.getElementById(layer).style.display="block";
		}
}

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

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;
}

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

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

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