function validateFormOnSubmit(theForm) {
var reason = "";
  
  if (theForm.id == "contactFormPrequalify") {
  reason += validateName(theForm.name);
  reason += validateEmail(theForm.email);
  reason += validatePhone(theForm.phone);
  reason += validateEmpty(theForm.loanterm);
  reason += validateEmpty(theForm.downpayment);
  reason += validateEmpty(theForm.timeonjob);
  reason += validateEmpty(theForm.dobmonth);
  reason += validateEmpty(theForm.dobday);
  reason += validateEmpty(theForm.dobyear);
  } 
  else if (theForm.id == "contactFormTradein") {
  reason += validateName(theForm.name);
  reason += validateEmail(theForm.email);
  reason += validatePhone(theForm.phone);
  reason += validateEmpty(theForm.make);
  reason += validateEmpty(theForm.model);
  reason += validateEmpty(theForm.year);
  reason += validateEmpty(theForm.miles);
  reason += validateEmpty(theForm.payoff);
  reason += validateEmpty(theForm.value);
  } 
  else if (theForm.id == "contactFormShort") {
  reason += validateName(theForm.name);
  reason += validateEmail(theForm.email);
  }
  else if (theForm.id == "contactFormG5" || 
	theForm.id == "contactFormG6Sedan" || 
	theForm.id == "contactFormG6Coupe" || 
	theForm.id == "contactFormG6Conv" || 
	theForm.id == "contactFormG8" || 
	theForm.id == "contactFormGrandPrix" || 
	theForm.id == "contactFormSolstice" || 
	theForm.id == "contactFormTorrent" || 
	theForm.id == "contactFormVibe" || 
	theForm.id == "contactBottomForm") {
  reason += validateName(theForm.name);
  reason += validateEmail(theForm.email);
  reason += validatePhone(theForm.phone);
  }
	else {
  reason += validateName(theForm.name);
  reason += validateEmail(theForm.email);
  reason += validatePhone(theForm.phone);
  }
  
  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    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 validateName(fld) {
    var error = "";
    var illegalChars = /[0-9]/; // allow letters no numbers
 
    if (fld.value == "") {
        fld.style.background = 'Yellow'; 
        error = "Please enter your name.\n";
    } else if ((fld.value.length < 2) || (fld.value.length > 30)) {
        fld.style.background = 'Yellow'; 
        error = "Your name is the wrong length.\n";
    } else if (illegalChars.test(fld.value)) {
        fld.style.background = 'Yellow'; 
        error = "The name you entered 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 = "Please enter your e-mail address.\n";
    } else if (!emailFilter.test(tfld)) {              //test email for illegal characters
        fld.style.background = 'Yellow';
        error = "Please enter a valid e-mail address.\n";
    } else if (fld.value.match(illegalChars)) {
        fld.style.background = 'Yellow';
        error = "The e-mail 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 = "Please enter your 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;
}