// JavaScript Document
function checkForm(theForm) {
  var input_name = theForm.name.value;
  var input_telephone = theForm.telephone.value;
  var input_email = theForm.email.value;
  var input_message = theForm.message.value;
  var check_code = theForm.check_code.value;
  
  	if (input_email == "") {
		var emailmatch = true;
	} else {
  	var emailpatern = /^[^@ ]+@[^@ ]+\.[^@ \.]+$/;
  	var emailmatch = emailpatern.test(input_email);
	}
	var ValidPhoneChars = "0123456789 ";	
	var IsPhoneNumber=true;
	
	for (i = 0; i < input_telephone.length && IsPhoneNumber == true; i++) {
		Char = input_telephone.charAt(i);
		if (ValidPhoneChars.indexOf(Char) == -1) {
			IsPhoneNumber=false;
		}
	}
  
  if (input_name != "") {
		if (input_telephone != "" || input_email != "") {
			if (IsPhoneNumber == true) {
				if (emailmatch) {
					if (input_message != "") {
						if (check_code != "") {
							return true;
						} else {
							alert("Please enter the 4 security digits.");
							return false;
						}
					} else {
						alert("Please include a query.");
						return false;
					}
				} else {
					alert("Yor email address is invalid.");
					return false;
				}
			} else {
				alert("Yor phone number is invalid.");
				return false;
			}

		} else {
		  alert("Please include your telephone number or your email address.");
		  return false;
		}
	} else {
	  alert("Please include your name.");
	  return false;
	}
}