//*************** Ajax functions **************//
function createXMLHttpRequest() 
 {
   try { return new ActiveXObject("Msxml2.XMLHTTP"); } catch (e) {}
   try { return new ActiveXObject("Microsoft.XMLHTTP"); } catch (e) {}
   try { return new XMLHttpRequest(); } catch(e) {}
   alert("XMLHttpRequest not supported");
   return null;
}
function sendUserMessage(agent_id,sender_name,txt)
{
	var pageObj = createXMLHttpRequest();
	pageObj.onreadystatechange = function(){
		if(pageObj.readyState == 4){			
			if(pageObj.status == 200)
			{
				var d=document.getElementById("displaymessage");		
				d.innerHTML+= "<br>"+pageObj.responseText;					
				d.scrollTop = d.scrollHeight;																																								
				document.getElementById("usermessage").value='';																																																								
			}
		}
	};		
	var args="agent_id="+agent_id+"&sender_name="+sender_name;	
	args+="&txt="+txt;
	//alert(args);	
	pageObj.open("POST", "saveusermessage.php", true);
	pageObj.setRequestHeader("Content-type", "application/x-www-form-urlencoded");				
	pageObj.send(args);		
}

function submit_user_message(txt,e,id,username)
{	
	if(!e)
		var k=event.keyCode;
	else
		var k=e.keyCode;
	if(k==13)	
		sendUserMessage(id,username,txt);	
}

function displayAgentMsgs(agent_id,sender_name)
{
	var pageObj = createXMLHttpRequest();
	pageObj.onreadystatechange = function(){
		if(pageObj.readyState == 4){			
			if(pageObj.status == 200)
			{				
				if(pageObj.responseText!='')
				{
					//alert(pageObj.responseText);
					var d=document.getElementById("displaymessage");		
					d.innerHTML+= "<br>"+pageObj.responseText;					
					d.scrollTop = d.scrollHeight;																																													
				}
			}
		}
	};		
	var args="agent_id="+agent_id+"&sender_name="+sender_name;			
	pageObj.open("POST", "displayagentmessage.php", true);
	pageObj.setRequestHeader("Content-type", "application/x-www-form-urlencoded");				
	pageObj.send(args);		
}

function displayAgentStatus()
{
	var newObj = createXMLHttpRequest();
	newObj.onreadystatechange = function(){
		if(newObj.readyState == 4){			
			if(newObj.status == 200)
			{				
				if(newObj.responseText!='')
				{
					var d=document.getElementById("changeStatus");		
					d.innerHTML= newObj.responseText;					
				}
			}
		}
	};		
	newObj.open("POST", "agent_status.php", true);
	newObj.setRequestHeader("Content-type", "application/x-www-form-urlencoded");				
	newObj.send('');		
}

function sendAgentMessage(txt)
{
	var pageObj = createXMLHttpRequest();
	pageObj.onreadystatechange = function()
	{
		if(pageObj.readyState == 4)
		{
			if(pageObj.status == 200)
			{
				if(pageObj.responseText!='')	
				{
					document.getElementById("agentChat").style.display='';																				
					var d=document.getElementById("displaymessage");	
					d.innerHTML+="<br>"+ pageObj.responseText;						
					d.scrollTop = d.scrollHeight;		
					document.getElementById("usermessage").value='';	
				}																								
			}
		}
	};		
	var args="txt="+txt;
	pageObj.open("POST", "saveagentmessage.php", true);
	pageObj.setRequestHeader("Content-type", "application/x-www-form-urlencoded");				
	pageObj.send(args);	
}

function displayUserMsgs()
{
	var pageObj = createXMLHttpRequest();
	pageObj.onreadystatechange = function()
	{
		if(pageObj.readyState == 4){
			if(pageObj.status == 200)
			{
				if(pageObj.responseText!='')	
				{				
					document.getElementById("agentChat").style.display='';														
					document.getElementById("messageBox").style.display='';
					var d=document.getElementById("displaymessage");	
					d.innerHTML+="<br>"+ pageObj.responseText;						
					d.scrollTop = d.scrollHeight;																																													
				}																								
			}
		}
	};		
	var args='';
	pageObj.open("POST", "displayusermessage.php", true);
	pageObj.setRequestHeader("Content-type", "application/x-www-form-urlencoded");				
	pageObj.send(args);	
}

function submit_agent_message(txt,e)
{
	if(!e)
		var k=event.keyCode;
	else
		var k=e.keyCode;		
	if(k==13)	
		sendAgentMessage(txt);				
}

function closeAgentChat()
{
	document.getElementById("agentChat").style.display='none';	
}