// JavaScript Document
var n = "";

function validate(n){
	var ret = true;
	var regEmail = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
	var regNumber = /^([0-9\-\.\+ ]){7,22}$/;
	var errMsg = '';
	
	switch(n)
	{
	case "contact":
	 	if(!document.forms['details'].firstname.value){
			errMsg += 'Please type your first name.\n';
			ret = false;
		}
		if(!document.forms['details'].lastname.value){
			errMsg += 'Please type your last name.\n';
			ret = false;
		}	
	 
	  break;  
	  
	case "join":
	 	if(!document.forms['details'].fullname.value){
			errMsg += 'Please type your full name.\n';
			ret = false;
		}
	
		if(!regNumber.exec(document.forms['details'].tel_no.value) || !document.forms['details'].tel_no.value){
			errMsg += 'Please specify a correct telephone number.\n';
			ret = false;
		}
	
	  break;
	} 

	if(!regEmail.exec(document.forms['details'].email.value) || !(document.forms['details'].email.value) ){
		errMsg += 'Please type a correct email address.\n';
		ret = false;
	}
	
	if(!ret) alert ('You have the following errors:\n\n' + errMsg);
	return ret;
}