function changeFocus(idVis){

		document.getElementById("focus"+idVis).className="focus";
		for(i=1;i<=3;i++){

			if(document.getElementById("focus"+i)){
				if(i!=idVis){
					document.getElementById("focus"+i).className="focushidden";
				}
			}
		}



}



function noWhitespace (s) {
	var whitespace="\t\r\n ";
	var i;
	if(isEmpty(s))
		return true;
	for (i=0;i<s.length;i++) {
		var c = s.charAt(i);
		if (whitespace.indexOf(c)!=-1)
			return false;
	}
	return true;
}

function isEmail (s) {
	var i = 1;
	var sLength = s.length;
	if (noWhitespace(s)) {
		while ((i<sLength) && (s.charAt(i) != "@")) { i++ }
		if ((i>=sLength) || (s.charAt(i) != "@"))
			return false;
		while ((i<sLength) && (s.charAt(i) != ".")) { i++ }
		if ((i>=sLength-2) || (s.charAt(i) != "."))
			return false;
		return true;
	}
	return false;
}

function isEmpty (s) { return ((s==null) || (s.length==0)) }


function  form_validate(){


	var err="";
	var returnvalue = true;
	
	
	if (document.getElementById("tb_AGNome").value=='') err += "Nome richiesto! \r\n";
	if (document.getElementById("tb_AGCognome").value=='') err += "Cognome richiesto! \r\n";
	if (document.getElementById("tb_AGTelefono").value=='') err += "Telefono richiesto! \r\n";
	if (document.getElementById("tb_AGEmail").value=='') err += "Email richiesta! \r\n";
	
	if (!isEmail(document.getElementById("tb_AGEmail").value)) err += "Email errata! \r\n";
	
	if(document.getElementById("tb_DataInizioAttivita") && document.getElementById("tb_DataInizioAttivita").value != ""){
	
		if(!IsDate(document.getElementById("tb_DataInizioAttivita").value)) err += "Controllare la data! \r\n";
	
	}
	
	if (!(document.getElementById("ch_privacy").checked)) 
				err += "Privacy richiesta! \r\n"; 
			
		
	if(err!=''){
	
		alert(err);
		return false
		
	}
	
}
	
	
function IsDate(data){

	var myreg = /^(((0[1-9]|[12][0-9]|3[01])([\-.\/])(0[13578]|10|12)([\-.\/])(\d{4}))|(([0][1-9]|[12][0-9]|30)([\-.\/])(0[469]|11)([\-.\/])(\d{4}))|((0[1-9]|1[0-9]|2[0-8])([\-.\/])(02)([\-.\/])(\d{4}))|((29)(\.|-|\/)(02)([\-.\/])([02468][048]00))|((29)([\-.\/])(02)([\-.\/])([13579][26]00))|((29)([\-.\/])(02)([\-.\/])([0-9][0-9][0][48]))|((29)([\-.\/])(02)([\-.\/])([0-9][0-9][2468][048]))|((29)([\-.\/])(02)([\-.\/])([0-9][0-9][13579][26])))$/;
	
	return myreg.test(data)
	
}