var DDSPEED = 10;
var DDTIMER = 15;



// main function to handle the mouse events //
function ddMenu(id,d){
  var h = document.getElementById(id + '-ddheader');
  var c = document.getElementById(id + '-ddcontent');
  clearInterval(c.timer);
  if(d == 1){
    clearTimeout(h.timer);
    if(c.maxh && c.maxh <= c.offsetHeight){return}
    else if(!c.maxh){
      c.style.display = 'block';
      c.style.height = 'auto';
      c.maxh = c.offsetHeight;
      c.style.height = '0px';
    }
    c.timer = setInterval(function(){ddSlide(c,1)},DDTIMER);
  }else{
    h.timer = setTimeout(function(){ddCollapse(c)},50);
  }
}

// collapse the menu //
function ddCollapse(c){
  c.timer = setInterval(function(){ddSlide(c,-1)},DDTIMER);
}

// cancel the collapse if a user rolls over the dropdown //
function cancelHide(id){
  var h = document.getElementById(id + '-ddheader');
  var c = document.getElementById(id + '-ddcontent');
  clearTimeout(h.timer);
  clearInterval(c.timer);
  if(c.offsetHeight < c.maxh){
    c.timer = setInterval(function(){ddSlide(c,1)},DDTIMER);
  }
}

// incrementally expand/contract the dropdown and change the opacity //
function ddSlide(c,d){
  var currh = c.offsetHeight;
  var dist;
  if(d == 1){
    dist = (Math.round((c.maxh - currh) / DDSPEED));
  }else{
    dist = (Math.round(currh / DDSPEED));
  }
  if(dist <= 1 && d == 1){
    dist = 1;
  }
  c.style.height = currh + (dist * d) + 'px';
  c.style.opacity = currh / c.maxh;
  c.style.filter = 'alpha(opacity=' + (currh * 100 / c.maxh) + ')';
  if((currh < 2 && d != 1) || (currh > (c.maxh - 2) && d == 1)){
    clearInterval(c.timer);
  }
}
function fontChange(size)	
{
	var size =size.toString()+"px";
	$("body").css("font-size",size);
    /* add by owen(21/10/2009)  refer 68900 */
    $("#fs-left font").css("font-size",size);
}

// following two functions will do mandatory field check for the search form.
//document.getElementById("errorTxt").style.display = 'none';
function validate_required(field,alerttxt)
{
with (field)
{
if (value==null||value=="")
  {
  	document.getElementById("errorTxt").innerText = alerttxt; // for IE
  	document.getElementById("errorTxt").style.display = 'block';
	document.getElementById("errorTxt").textContent = alerttxt; // for the rest of the known world
  	return false;
  }
else {return true}
}
}

function validate_form(thisform)
{
with (thisform)
{
if (validate_required(searchText,"Please enter a keyword to search.")==false)
  {searchText.focus();return false;}
}
}
function validate_form2(thisform, language)
{
with (thisform)
{
if (language="")
{var errorMsg="Please enter a keyword to search."}
else {var errorMsg="Please enter a keyword to search."}
if (validate_required(searchText,errorMsg)==false)
  {searchText.focus();return false;}
}
}
function validate_form2(thisform, language)
{
var errorMsg;
if (language=="ENG") {errorMsg="Please enter a keyword to search.";}
if (language=="VIT") {errorMsg="Nhập từ khóa để tìm.";}

with (thisform)
{
if (validate_required(searchText,errorMsg)==false)
  {searchText.focus();return false;}
}
}