var currentElementId = '';
var needsToExpand = false;
function hideAndShow(elementId)
{                    
    if (currentElementId != elementId)
    {                                
        if (needsToExpand)
        {
            new Effect.Scale ('secondary-nav-container', 100, {scaleX: false, scaleY: true, scaleContent: false, scaleFrom: 10, scaleMode: {originalHeight: 101, originalWidth: 750 }});
            needsToExpand = false;
        }
        if (currentElementId != '')
        {
            new Effect.Fade(currentElementId, { queue: 'end', duration: 0.4 });
        }
        new Effect.Appear(elementId, { queue: 'end', duration: 1.2 });     
        currentElementId = elementId; 
                        
        diableCurrentLink();
    }
}

function diableCurrentLink()
{
    document.getElementById("link-get-involved").className="default";  
    document.getElementById("link-read").className="default";  
    document.getElementById("link-write").className="default";  
    document.getElementById("link-talk").className="default";  
    
    if (currentElementId == 'sn-get-involved')
    {
        //document.getElementById("link-get-involved").style.cursor="default"; 
        document.getElementById("link-get-involved").className="current";                                
    }
    if (currentElementId == 'sn-read')
    {
        //document.getElementById("link-read").style.cursor="default";                
        document.getElementById("link-read").className="current";  
    }
    if (currentElementId == 'sn-write')
    {
        //document.getElementById("link-write").style.cursor="default";                
        document.getElementById("link-write").className="current";  
    }
    if (currentElementId == 'sn-talk')
    {
        //document.getElementById("link-talk").style.cursor="default";                
        document.getElementById("link-talk").className="current";  
    }
}

function showRead()
{            
    hideAndShow('sn-read');            
}
function showWrite()
{                      
    hideAndShow('sn-write');            
}
function showTalk()
{                                     
    hideAndShow('sn-talk');         
}
function showGetInvolved()
{                                      
    hideAndShow('sn-get-involved');            
}

function positionElement(element)
{
    element.style.visibility = "hidden";
    element.style.display = "none";
    element.style.position="absolute";
    element.style.left="0px";
    element.style.top="0px"; 
    element.style.visibility = "visible";                          
}
function SetupCorrectNavForPage()
{
    if (document.body.className == 'read')
    {
        document.getElementById("sn-read").style.display='inline';
        currentElementId = 'sn-read';
    }
    if (document.body.className == 'write')
    {
        document.getElementById("sn-write").style.display='inline';
        currentElementId = 'sn-write';
    }
    if (document.body.className == 'talk')
    {
        document.getElementById("sn-talk").style.display='inline';
        currentElementId = 'sn-talk';
    }
    if (document.body.className == 'get-involved')
    {
        document.getElementById("sn-get-involved").style.display='inline';
        currentElementId = 'sn-get-involved';
    }
    if (document.body.className == 'home')
    {
        needsToExpand = true;
    }
    diableCurrentLink();
}
function SetupPage ()
{                               
    document.getElementById("link-get-involved").href='javascript:showGetInvolved();';            
    positionElement(document.getElementById("sn-get-involved"));
    
    document.getElementById("link-read").href='javascript:showRead();';            
    positionElement(document.getElementById("sn-read"));
    
    document.getElementById("link-write").href='javascript:showWrite();';
    positionElement(document.getElementById("sn-write"));
    
    document.getElementById("link-talk").href='javascript:showTalk();';
    positionElement(document.getElementById("sn-talk"));
                
    SetupCorrectNavForPage();            
}

// JS function from http://webborg.blogspot.com/2007/07/querystring-get-parameters-from-url.html
function queryString(parameter) { 
  var loc = location.search.substring(1, location.search.length);
  var param_value = false;

  var params = loc.split("&");
  for (i=0; i<params.length;i++) {
      param_name = params[i].substring(0,params[i].indexOf('='));
      if (param_name == parameter) {
          param_value = params[i].substring(params[i].indexOf('=')+1)
      }
  }
  if (param_value) {
      return param_value;
  }
  else {
      return false; //Here determine return if no parameter is found
  }
}