function validateFormOnSubmit(theForm) {
var reason = "";

  reason += validateEmpty(theForm.firstname);
  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    theForm.firstname.focus();
    return false;
  }
  reason += validateEmpty(theForm.Lastname);
  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    theForm.Lastname.focus();
    return false;
  }
  reason += validateEmpty(theForm.Address);
  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    theForm.Address.focus();
    return false;
  }
  reason += validateEmpty(theForm.City);
  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    theForm.City.focus();
    return false;
  }
  reason += validateEmpty(theForm.zip);
  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    theForm.zip.focus();
    return false;
  }
  reason += validateEmpty(theForm.lender);
  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    theForm.lender.focus();
    return false;
  }
  reason += validateEmpty(theForm.monthly_payment);
  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    theForm.monthly_payment.focus();
    return false;
  }
  reason += validateEmpty(theForm.months_behind);
  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    theForm.months_behind.focus();
    return false;
  }
  reason += validateEmpty(theForm.main_goal);
  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    theForm.main_goal.focus();
    return false;
  }
  reason += validatePhone(theForm.home_phone);
  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    theForm.home_phone.focus();
    return false;
  }
  reason += validatePhone(theForm.work_phone);
  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    theForm.work_phone.focus();
    return false;
  }
  reason += validateEmail(theForm.email);
  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    theForm.email.focus();
    return false;
  }

  return true;
}

function validateEmpty(fld) {
    var error = "";
  
    if (fld.value.length == 0) {
        fld.style.background = 'Yellow'; 
        error = "The required field has not been filled in.\n"
    } else {
        fld.style.background = 'White';
    }
    return error;   
}

function validateUsername(fld) {
    var error = "";
    var illegalChars = /\W/; // allow letters, numbers, and underscores
 
    if (fld.value == "") {
        fld.style.background = 'Yellow'; 
        error = "You didn't enter a username.\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 = "The username contains illegal characters.\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 = "You didn't enter an email address.\n";
    } else if (!emailFilter.test(tfld)) {              //test email for illegal characters
        fld.style.background = 'Yellow';
        error = "Please enter a valid email address.\n";
    } else if (fld.value.match(illegalChars)) {
        fld.style.background = 'Yellow';
        error = "The email address contains illegal characters.\n";
    } else {
        fld.style.background = 'White';
    }
    return error;
}

function validatePhone(fld) {
    var error = "";
    var stripped = fld.value.replace(/[\(\)\.\-\ ]/g, '');     

   if (fld.value == "") {
        error = "You didn't enter a phone number.\n";
        fld.style.background = 'Yellow';
    } else if (isNaN(parseInt(stripped))) {
        error = "The phone number contains illegal characters.\n";
        fld.style.background = 'Yellow';
    } else if (!(stripped.length == 10)) {
        error = "The phone number is the wrong length. Make sure you included an area code.\n";
        fld.style.background = 'Yellow';
    } 
    return error;
}