//function to initialise httpRequest object
function GetXmlHttpObject(){ 
	var objXMLHttp=null
	if (window.XMLHttpRequest){
		objXMLHttp=new XMLHttpRequest()
	}else if (window.ActiveXObject){
		objXMLHttp=new ActiveXObject("Microsoft.XMLHTTP")
	}
	return objXMLHttp
} 
//create xmlHttp - httpRequest Object
var xmlHttp
//show content of selected page
function showContent(section, page){
	xmlHttp=GetXmlHttpObject()
	//check if browser supports httpRequest
	if (xmlHttp==null){
		alert ("Browser does not support HTTP Request")
		return
	}
	//get info on page/section ref get_page.php
	var url="inc/get_page.php?page="+page+"&section="+section;
	xmlHttp.onreadystatechange=stateChanged 
	xmlHttp.open("GET",url,true)
	xmlHttp.send(null)
	if(page == 34){jlc_init()}
}
function stateChanged(){ 
	if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete"){ 
		//write current page content into page
		document.getElementById("pageContent").innerHTML=xmlHttp.responseText 
	} 
} 
//function to display download section on jlc page (links & downloads)
function jlc_init(){
	var today = new Date()
	if ((today.getMonth() < 7) || (today.getMonth() > 9)) {
		document.getElementById('formDownload').style.display = 'none';
	} else {
		if ((today.getMonth() == 9) && (today.getDate() > 15)) {
		document.getElementById('formDownload').style.display = 'none';
		}
	}
}	

//get news headlines
var newsPage
function newsEvents(page){
	newsPage = page;
	xmlHttp=GetXmlHttpObject()
	if (xmlHttp==null){
		alert ("Browser does not support HTTP Request")
		return
	} 
	var url = "inc/get_news.php?page="+page;
	xmlHttp.onreadystatechange=newsPageChanged 
	xmlHttp.open("GET",url,true)
	xmlHttp.send(null)
}
function newsPageChanged(){
	if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete"){
		//receive json encoded data from get_news.php
		var jsonText = xmlHttp.responseText;
		//parse json array into news headline items
		jsonArr = jsonText.parseJSON()
		if(newsPage == 'news'){
			// display header and click instruction for relevant page - "News" or "Events"
			document.getElementById("header").innerHTML='News<br/>';
			document.getElementById("instr").innerHTML='Click on headline to see news item...';
			var result = "";
			//create link to displayItem function for each news headline
			for(i=0;i<jsonArr.length;i++){
				result += "<a style='color: #000000' href='javascript:displayNewsItem("+jsonArr[i][0]+")'>"+jsonArr[i][1]+"</a><br>";
			}
		}else{
			document.getElementById("header").innerHTML='';
			document.getElementById("instr").innerHTML=evHead;
			var result = "<table border='0' cellspacing='0' cellpadding='0'>";
			for(i=0;i<jsonArr.length;i++){
				result += "<tr><td class='headLine'>"+jsonArr[i][1]+"</td></tr>";
				result += "<tr><td class='newsDate'>"+jsonArr[i][0]+"</td></tr>";
				result += "<tr><td class='newsContent'>"+jsonArr[i][2]+"</td></tr>";
				result += "<tr><td>&nbsp</td></tr>";
			}
			result +=	"</table>";
		}
		document.getElementById("pageContent").innerHTML=result; 
	}
}
//f to display news item content
function displayNewsItem(id){
	xmlHttp=GetXmlHttpObject()
	if (xmlHttp==null){
		alert ("Browser does not support HTTP Request")
		return
	} 
	var url = "inc/get_news_content.php?item="+id;
	xmlHttp.onreadystatechange=displayNewsContent
	xmlHttp.open("GET",url,true)
	xmlHttp.send(null)
}
function displayNewsContent(){ 
	if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete"){
		//gets headline, date and content of news item as json array
		var jsonText = xmlHttp.responseText;
		jsonArr = jsonText.parseJSON()
		//creates a variable containing headline, date and content of news item
		var news_content = "<table border=0 cellpadding=0 cellspacing=0><tr>";
		news_content += "<td class='headLine'>"+jsonArr['news_headline']+"</td>";
		news_content += "<td class='newsDate'>"+jsonArr['news_date']+"</td></tr>";
		news_content += "<tr><td colspan='2' class='newsContent'>"+jsonArr['news_content']+"</td></tr></table>";
		//clears header
		document.getElementById("instr").innerHTML = "";
		//display news item
		document.getElementById("pageContent").innerHTML=news_content; 
	}
}