function validateEmpty(fld) {
    var error = "";

    if (fld.value.length == 0) {
        fld.style.background = 'Yellow';
        error = "Väli täitmata.\n"
    } else {
        fld.style.background = 'White';
    }
    return error;
}
function validateName(fld) {
    var error = "";
    var illegalChars = /\W/; // allow letters, numbers, and underscores

    if (fld.value == "") {
        fld.style.background = 'Yellow';
        error = "Väli täitmata.\n";
    // }  else if ((fld.value.length < 5) || (fld.value.length > 15)) {
      //  fld.style.background = 'Yellow';
      //  error = "The username is the wrong length.\n";
    } else if (illegalChars.test(fld.value)) {
        fld.style.background = 'Yellow';
        error = "Sisaldab lubamatuid sümboleid.\n";
    } else {
        fld.style.background = 'White';
    }
    return error;
}

function validatePassword(fld) {
    var error = "";
    var illegalChars = /[\W_]/; // allow only letters and numbers

    if (fld.value == "") {
        fld.style.background = 'Yellow';
        error = "You didn't enter a password.\n";
    } else if ((fld.value.length < 7) || (fld.value.length > 15)) {
        error = "The password is the wrong length. \n";
        fld.style.background = 'Yellow';
    } else if (illegalChars.test(fld.value)) {
        error = "The password contains illegal characters.\n";
        fld.style.background = 'Yellow';
    } else if (!((fld.value.search(/(a-z)+/)) && (fld.value.search(/(0-9)+/)))) {
        error = "The password must contain at least one numeral.\n";
        fld.style.background = 'Yellow';
    } else {
        fld.style.background = 'White';
    }
   return error;
}
function trim(s)
{
  return s.replace(/^\s+|\s+$/, '');
}
function validateEmail(fld) {
    var error="";
    var tfld = trim(fld.value);                        // value of field with whitespace trimmed off
    var emailFilter = /^[^@]+@[^@.]+\.[^@]*\w\w$/ ;
    var illegalChars= /[\(\)\<\>\,\;\:\\\"\[\]]/ ;

    if (fld.value == "") {
        fld.style.background = 'Yellow';
        error = "Palun sisesta email.\n";
    } else if (!emailFilter.test(tfld)) {              //test email for illegal characters
        fld.style.background = 'Yellow';
        error = "Palun sisesta korrektne emaili aadress.\n";
    } else if (fld.value.match(illegalChars)) {
        fld.style.background = 'Yellow';
        error = "Email sisaldab lubamatuid sümboleid.\n";
    } else {
        fld.style.background = 'White';
    }
    return error;
}
function validatePhone(fld) {
    var error = "";
    var stripped = fld.value.replace(/[\+\(\)\.\-\ ]/g, '');

   if (fld.value == "") {
        error = "Palun sisesta telefon.\n";
        fld.style.background = 'Yellow';
    } else if (isNaN(parseInt(stripped))) {
        error = "Telefoninumbris on lubamatud sümbolid.\n";
        fld.style.background = 'Yellow';
    } else if ((stripped.length < 6)) {
        error = "Telefoninumber liiga lühike.\n";
        fld.style.background = 'Yellow';
    }
    return error;
}