//Author: Daniel R. Bauer

function loadHome(){
	autoScroll();
}

function autoScroll(){
	myDiv = document.getElementById("chatbox");
       	myDiv.scrollTop = myDiv.scrollHeight;
}

//AJAX functions. These provide the website with AJAX capabilities.

//returns the text inside of the XML tag specified by the parameter tagelem 
function retrieveXML(tagelem){
	if (window.ActiveXObject){
		return tagelem.text;
	}
	else{
        return tagelem.textContent;
	}
}

function refreshChat(){
	var getrequest = ajaxRequest();
	var url = "uiutils/chatbox.php";
	getrequest.onreadystatechange=function(){
		if (getrequest.readyState==4){
			document.getElementById("chatboxFrame").innerHTML=getrequest.responseText;
			autoScroll();
		}
	}
	getrequest.open("GET",url,true);
	getrequest.send(null);
}

function postComment(user,comment,count){
	var getrequest = ajaxRequest();
	var url = "utils/chat.php?uname="+user+"&comment="+comment+"&count="+count;
	count++;
	getrequest.onreadystatechange=function(){
		if (getrequest.readyState==4){
			if (getrequest.responseText == "Error")
				document.getElementById("errMsg").style.display="inline";
			else{
				document.getElementById("chatbox").innerHTML=document.getElementById("chatbox").innerHTML+getrequest.responseText;
				document.getElementById("errMsg").style.display="none";
			}
			document.getElementById("uname").value="";
			document.getElementById("comment").value="";
			document.getElementById("count").value=count;
			autoScroll();
		}
	} 
	getrequest.open("GET",url,true);
	getrequest.send(null);
}

function castVote(poll,option){
	var getrequest = ajaxRequest();
	var url = "utils/castVote.php?poll="+poll+"&option="+option;

	getrequest.onreadystatechange=function(){
		if (getrequest.readyState==4){
			document.getElementById("selected").value="";
			for (var i = 0;i<document.getElementsByName("option").length;i++){
				document.getElementsByName("option")[i].checked=false;
			}
			if (getrequest.responseText != 'Error'){
				var href = location.href;
				var loc = href.split("/");
				if (loc[loc.length-1] == "pollview.php"){
					location.reload();
				}
				else{
					var n = poll-1;
					document.getElementById("pollMsg"+n).style.display="inline";
				}
			}
		}
	}
	getrequest.open("GET",url,true);
	getrequest.send(null);
}

//returns an ActiveXObject if Microsoft Internet Explorer is the browser
//returns an XMLHttpRequest if another browser is used.
function ajaxRequest(){
	var ajaxObject;
	if (window.XMLHttpRequest)
		ajaxObject = new XMLHttpRequest();
	else if (window.ActiveXObject)
		ajaxObject = new ActiveXObject("Microsoft.XMLHTTP");

	return ajaxObject;
}