var seenAlerts = new Array();

function alertsOnLoad(){
	loadAlertSettings();
}

function loadAlertSettings(){
	var urlString = "HideAlerts=";
	var start = document.cookie.indexOf(urlString);
	if (start == -1){ return; }
	start += urlString.length;
	var end = document.cookie.indexOf(";", start);
	if (end == -1){ end = document.cookie.length; }
	var alertData = unescape(document.cookie.substring(start, end));
	hideSeenAlerts(alertData);
}

function hideSeenAlerts(alertString){
	var alerts = alertString.split(",");
	for(var a = 0; a < alerts.length; a++){
		hideAlert(alerts[a]);
		seenAlerts.push(alerts[a]);
	}
}

function hideAlert(alertID){
	var sect = document.getElementById(alertID);
	var clas = sect.className;
	clas = clas.replace('visible', 'hidden' );
	sect.className = clas;	
	seenAlerts.push(alertID);
	saveSeenAlerts();
}

function saveSeenAlerts(){
	var arrs = uniqueArray(seenAlerts);
	seenAlerts = arrs;
	var urlString = "HideAlerts=" + escape(arrs.join(","));
	var today = new Date();
	var expire = new Date(today.getTime() + 7 * 1000 * 60 * 60 * 24);
	document.cookie = urlString + ";expires=" + expire.toGMTString();
}

function uniqueArray(arr){
   var u = {}, a = [];
   for(var i = 0, l = arr.length; i < l; ++i){
      if(arr[i] in u)
         continue;
      a.push(arr[i]);
      u[arr[i]] = 1;
   }
   return a;
}