function randomString() {
	var chars = "ABCDE";
	var string_length = 5;
	var randomstring = '';
	for (var i=0; i<string_length; i++) {
		var rnum = Math.floor(Math.random() * chars.length);
		randomstring += chars.substring(rnum,rnum+1);
	}
	return randomstring;
}

function populate_invite_link(user,element,base_URL){
		var invite_link_container = document.getElementById('invite_link');
		invite_link_container.value = base_URL+user+'_'+randomString();
	}


function replace_unwanted_chars(user_value){	
	
	if (user_value.match(/[^a-zA-Z0-9]/)){
		user_value = user_value.replace(/[^a-zA-Z0-9]/g, '-');
	}
	
	return user_value;
}


function repopulate_invite_link(user_value,instance,base_URL){
		user_value=replace_unwanted_chars(user_value);
		var invite_link_container = document.getElementById('invite_link');
		//var user_container = document.getElementById('user');
		invite_link_container.value = base_URL+user_value+'_'+instance;
		
	}


function disable_submit(){
	if(document.getElementById('submit_btn')){
		document.getElementById('submit_btn').disabled = true;
		}
	}
	
function enable_submit(){
	document.getElementById('submit_btn').disabled = false;
	}
	
function openIM(invite_link){
	window.open(invite_link+'/im','AVChatIM', 'height=640,width=800,location=1');
	exit;
}

function replace_scnd_user_unwated_chars(user_value){
	var user_container = document.getElementById('user');
	var fake_user_container = document.getElementById('fake_user');
	
	user_value = replace_unwanted_chars(user_value);
	
	fake_user_container.value = user_value;	
}