var digits = "0123456789";
var phoneNumberDelimiters = "()-+ ";
var validNLPhoneChars = digits + phoneNumberDelimiters;
var digitsInNLPhoneNumber = 10;
var whitespace = " \t\n\r";

var iEmail = "Vul een juist e-mail adres in.";
var iNLPhone = "Vul een juist telefoonnummer in (minimaal 10 cijfers).";

var defaultEmptyOK = false;
var defaultMsgOK = true;

function prompt (s)
{   window.status = s
}

function warnEmpty (theField, s)
{   theField.focus()
    alert(mPrefix + s + mSuffix)
    return false
}

function warnInvalid (theField, s)
{   theField.focus()
    theField.select()
    alert(s)
    return false
}

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

function isWhitespace (s)
{   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 stripCharsInBag (s, bag)
{   var i;
    var returnString = "";
    for (i = 0; i < s.length; i++)
    {   var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }
   return returnString;
}

function isDigit (c)
{   return ((c >= "0") && (c <= "9"))
}

function isInteger (s)
{   var i;
    if (isEmpty(s)) 
       if (isInteger.arguments.length == 1) return defaultEmptyOK;
       else return (isInteger.arguments[1] == true);
    for (i = 0; i < s.length; i++)
    {   var c = s.charAt(i);
        if (!isDigit(c)) return false;
    }
    return true;
}

function isEmail (s)
{   if (isEmpty(s)) 
       if (isEmail.arguments.length == 1) return defaultEmptyOK;
       else return (isEmail.arguments[1] == true);
    if (isWhitespace(s)) return false;
    var i = 1;
    var sLength = s.length;
    while ((i < sLength) && (s.charAt(i) != "@"))
    { i++
    }
    if ((i >= sLength) || (s.charAt(i) != "@")) return false;
    else i += 2;
    while ((i < sLength) && (s.charAt(i) != "."))
    { i++
    }
    if ((i >= sLength - 1) || (s.charAt(i) != ".")) return false;
    else return true;
}

function isNLPhoneNumber (s)
{   if (isEmpty(s)) 
       if (isNLPhoneNumber.arguments.length == 1) return defaultEmptyOK;
       else return (isNLPhoneNumber.arguments[1] == true);
    return (isInteger(s) && s.length >= digitsInNLPhoneNumber)
}

function checkEmail (theField, emptyOK, msgOK)
{   if (checkEmail.arguments.length == 1) emptyOK = defaultEmptyOK;
    if (checkEmail.arguments.length == 2) msgOK = defaultMsgOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    else if (!isEmail(theField.value, false))
         {  if (msgOK == true) return warnInvalid (theField, iEmail);
            return false;
         }
    else return true;
}

function checkNLPhone (theField, emptyOK, msgOK)
{   if (checkNLPhone.arguments.length == 1)
    {  emptyOK = defaultEmptyOK;
       msgOK = defaultMsgOK;
    }
    if (checkNLPhone.arguments.length == 2) msgOK = defaultMsgOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    else
    {  var normalizedPhone = stripCharsInBag(theField.value, phoneNumberDelimiters)
       if (!isNLPhoneNumber(normalizedPhone, false))
       {  if (msgOK == true) return warnInvalid (theField, iNLPhone);
          return false;
       }
       else return true;
    }
}

function validateFormInfo(form) { // ttt_site
	if ( (form.elements["persoon"].value == 0) && (form.elements["bedrijfsnaam"].value == 0) ) {
		alert('Vul uw naam of bedrijfsnaam in.');
		return false;
	}
	else
	{
		// alert('Naam of bedrijfsnaam ingevuld');
	}

	if ( (form.elements["telefoon"].value == 0) && (form.elements["email"].value == 0) ) {
   	alert('Vul uw telefoonnummer of e-mail adres in.');
		return false;
	}
	else
	{
		// alert('Telefoon of E-mail ingevuld.');
	}

	if ( (form.elements["telefoon"].value != 0) && (form.elements["email"].value != 0) ) {
		if ( (checkNLPhone(form.elements["telefoon"], false, true)) && (checkEmail(form.elements["email"], false, true)) ) {
		//	alert('oke! beide goed.');
			return true;
		}
		else
		{
			return false;
		}
	}	

	if ( ( (form.elements["telefoon"].value == 0) ) &&
	     ( (form.elements["email"].value != 0) && (checkEmail(form.elements["email"], false, true)) ) ) {
	//	alert('oke! tel leeg en email goed.');
		return true;
	}

	if ( ( (form.elements["telefoon"].value != 0) && (checkNLPhone(form.elements["telefoon"], false, true)) ) &&
	     ( (form.elements["email"].value == 0) ) ) {
	//	alert('oke! tel goed en email leeg.');
		return true;
	}

	return false;
}