/* swiped from http://images.tribe.net/tribe/js/Utils.js */

// toggle visibility of a div and its image if available
//
// usage: <a href="javascript:toggleDisplay('divId')">
//
// where: fieldname = id of div to toggle
//        fieldnameDIV = id of hidden form element
//        fieldnameIMG = id of toggle image (optional)
//        fieldnameMOD = module to toggle
// 
// note: show() and hide() are used in ListingFieldsHead.vm's $bodyArgs
// to set the proper state when the page is (re)loaded

function toggleDisplay(id) {
  var myElement = document.getElementById(id);
  if (myElement) {
    if( myElement.style.display == "none") {
      show(id);
    } 
    else {
      hide(id);
    }
  }
}

function show(id) {
  if(document.getElementById(id)) {
    document.getElementById(id).style.display = "block";
    // toggle hidden form element if it exists
    if( document.getElementById(id + 'DIV') ) {
      document.getElementById(id + 'DIV').value = "show";
    }
    // toggle image if it exists
    if( document.getElementById(id + 'IMG') ) {
      document.getElementById(id + 'IMG').src = "/tribe/images/redesign/form_expanded.gif";
    }
    // toggle header image if it exists
    if( document.getElementById(id + 'HDR') ) {
      document.getElementById(id + 'HDR').src = "/tribe/images/redesign/hdr_expanded.gif";
    }
    // toggle header image if it exists
    if( document.getElementById(id + 'MOD') ) {
      document.getElementById(id + 'MOD').className = "moduleExpanded";
    }
  }
}

function hide(id) {
  if(document.getElementById(id)) {
    document.getElementById(id).style.display = "none"; 
    // toggle hidden form element if it exists
    if( document.getElementById(id + 'DIV') ) {
      document.getElementById(id + 'DIV').value = "hide";
    }
    // toggle image if it exists
    if( document.getElementById(id + 'IMG') ) {
      document.getElementById(id + 'IMG').src = "/tribe/images/redesign/form_collapsed.gif";
    }
    // toggle header image if it exists
    if( document.getElementById(id + 'HDR') ) {
      document.getElementById(id + 'HDR').src = "/tribe/images/redesign/hdr_collapsed.gif";
    }
    // toggle header image if it exists
    if( document.getElementById(id + 'MOD') ) {
      document.getElementById(id + 'MOD').className = "moduleCollapsed";
    }
  }
}

/* swiped from http://www.thinksecret.com/backswitch.js */
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);