// form validation function //
function validate(form) {
  var name = form.name.value;
  var surname = form.surname.value;
  var email = form.email_address.value;
  var email0 = form.email_address0.value;
  var home_telephone = form.home_telephone.value;
  var work_telephone = form.work_telephone.value;
  var mobile_telephone = form.mobile_telephone.value;
  var address1 = form.address1.value;
  var address2 = form.address2.value;
  var town = form.town.value;
  var county = form.county.value;
  var postcode = form.postcode.value;
  var password = form.password.value;
  var password0 = form.password0.value;
  var password_reminder_question = form.password_reminder_question.value;
  var password_reminder_answer = form.password_reminder_answer.value;
  var TnC = form.TnC.value;
  var securityCode = form.securityCode.value;
    var emailRegex = /^[\w-\.]+@([\w-]+\.)+[\w-]{2,4}$/;
  
  if(name == "") {
    alert('You must enter your name.');
    form.name.focus();
    return false;
  }

  if(surname == "") {
    alert('You must enter your surname.');
    form.surname.focus();
    return false;
  }

  if(email == "") {
    alert('You must enter your email.');
    form.email_address.focus();
    return false;
  }
  
      if(!email.match(emailRegex)) {
    alert('You have entered an invalid email address.');
    form.email_address.focus();
    return false;
  }

  
  if(email0 == "") {
    alert('You must enter your email.');
    form.email_address0.focus();
    return false;
  }
  
      if(!email0.match(emailRegex)) {
    alert('You have entered an invalid email address.');
    form.email_address0.focus();
    return false;
  }


  if(email0 != email) {
    alert('Your email addresses do not match.');
    form.email_address0.focus();
    return false;
  }
  
  if(home_telephone == "") {	
    alert('You must enter your home telephone number.');
    form.home_telephone.focus();
    return false;
  }
  
  if(work_telephone == "") {	
    alert('You must enter your work telephone number.');
    form.work_telephone.focus();
    return false;
  }

  if(mobile_telephone == "") {	
    alert('You must enter your mobile telephone number.');
    form.mobile_telephone.focus();
    return false;
  }
  
  if(address1 == "") {
    alert('You must enter your address.');
    form.address1.focus();
    return false;
  }

  if(town == "") {
    alert('You must enter your town.');
    form.town.focus();
    return false;
  }
  
  if(county == "") {
    alert('You must enter your county.');
    form.county.focus();
    return false;
  }
  
  if(postcode == "") {
    alert('You must enter your postcode.');
    form.postcode.focus();
    return false;
  }

  if(password == "") {
    alert('You must enter your password.');
    form.password.focus();
    return false;
  }
  
  if(password0 == "") {
    alert('You must enter your password.');
    form.password0.focus();
    return false;
  }

  if(password0 != password) {
    alert('Your passwords do not match.');
    form.password0.focus();
    return false;
  }
  
  if(password_reminder_question == "") {
    alert('You must enter your password_reminder_question.');
    form.password_reminder_question.focus();
    return false;
  }

  if(password_reminder_answer == "") {
    alert('You must enter your password reminder answer.');
    form.password_reminder_answer.focus();
    return false;
  }

  
  if(securityCode == "") {
    alert('You must enter the code shown in the picture.');
    form.securityCode.focus();
    return false;
  }

  if(TnC == "") {
    alert('You must agree to the terms and conditions.');
    form.TnC.focus();
    return false;
  }
  
  return true;
}