var httpObject = null;  

var id;
var offset=0;
var pg = 12;
var page=0;
var total_pages=0;
var pag =0;
String.prototype.trim = function () 

{

	return this.replace(/^\s*/, "").replace(/\s*$/, "").replace(".","");

}

// Get the HTTP Object

function getHTTPObject()

{

if (window.ActiveXObject) return new ActiveXObject("Microsoft.XMLHTTP");

else if (window.XMLHttpRequest) return new XMLHttpRequest();

else {

alert("Your browser does not support AJAX.");

return null;

}

}

function nextpage(next,pages)
{
  offset = next;
  total_pages=pages
  pag = (parseInt(pages)*12);
// alert ("hai"+pag);
	if(next!=pag)
	{
		
		httpObject = getHTTPObject();

		if (httpObject != null) 

		{
			
			httpObject.open("GET", "playlist.php?next_page="+next, true);

			httpObject.onreadystatechange = setOutput_next_page;

			httpObject.send(null);

			return next;

		}
		
		else

			return false;

	}
	else

			return false;
	
		
}



function setOutput_next_page()
{

	if(httpObject.readyState == 4)

	{

		if(httpObject.responseText.trim()!=0)
		{
			document.getElementById('US1').innerHTML=httpObject.responseText.trim();
			offset = parseInt(offset) + 12;
			page = (parseInt(offset)/12);
			//alert("hai"+page);
			document.getElementById('pg1').innerHTML="Page "+page+" of "+total_pages;
			document.getElementById('offset').value=offset;
		}

		else

		{
			
			document.getElementById('offset').value=0;

			nextpage(1);

		}

	}

}

function prevpage(prev,pages)
{
  offset = prev;
   total_pages=pages;
 //alert("hai"+prev)
 if(prev!=12)

	{
		
		httpObject = getHTTPObject();

		if (httpObject != null) 

		{
			
			httpObject.open("GET", "playlist.php?prev_page="+prev, true);

			httpObject.onreadystatechange = setOutput_prev_page;

			httpObject.send(null);

			return prev;

		}
		
		else

			return false;

	}
	else
	{
		return false;
	}
	
		
}


function setOutput_prev_page()
{

	if(httpObject.readyState == 4)

	{

		if(httpObject.responseText.trim()!=0)
		{
			document.getElementById('US1').innerHTML=httpObject.responseText;
			offset = parseInt(offset) - 12;
			page = (parseInt(offset)/12);
			//alert("hai"+page);
			document.getElementById('pg1').innerHTML="Page "+page+" of "+total_pages;
			document.getElementById('offset').value=offset;
		}

		else

		{
			
			document.getElementById('offset').value=0;

			prevpage(1);

		}

	}

}