// JavaScript Document

String.prototype.Trim = function() { 
	return this.replace(/(^\s*)|(\s*$)/g, ""); 
} 

// return the value of the radio button that is checked
// return an empty string if none are checked, or
// there are no radio buttons
function getCheckedValue(radioObj) {
	if(!radioObj)
		return "";
	var radioLength = radioObj.length;
	if(radioLength == undefined)
		if(radioObj.checked)
			return radioObj.value;
		else
			return "";
	for(var i = 0; i < radioLength; i++) {
		if(radioObj[i].checked) {
			return radioObj[i].value;
		}
	}
	return "";
}

// set the radio button with the given value as being checked
// do nothing if there are no radio buttons
// if the given value does not exist, all the radio buttons
// are reset to unchecked
function setCheckedValue(radioObj, newValue) {
	if(!radioObj)
		return;
	var radioLength = radioObj.length;
	if(radioLength == undefined) {
		radioObj.checked = (radioObj.value == newValue.toString());
		return;
	}
	for(var i = 0; i < radioLength; i++) {
		radioObj[i].checked = false;
		if(radioObj[i].value == newValue.toString()) {
			radioObj[i].checked = true;
		}
	}
}

function checkMail(email) {
	var x = email;
	var filter  = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
	if (filter.test(x)) return true;
	else return false;
}

function checkContactUs(myForm) {
	var contactPerson = myForm.contactPerson;
	var email = myForm.email;
	var message = myForm.message;
	var sendFlag = true;
		
	if (contactPerson.value.Trim() == "" && sendFlag){
		alert("Please input your name");
		sendFlag = false;
		contactPerson.focus();
	}
	
	if (email.value.Trim() == "" && sendFlag){
		alert("Please input your email address");
		sendFlag = false;
		email.focus();
	} else if (!checkMail(email.value.Trim()) && sendFlag) {
		alert("Invalid email format. Please input again");
		sendFlag = false;
		email.focus();
	}
	
	if (message.value.Trim() == "" && sendFlag){
		alert("Please leave your message");
		sendFlag = false;
		message.focus();
	}
	
	if (sendFlag) {
		myForm.btnSubmit.disabled = "disabled";
	}
	
	return sendFlag;
}

function checkEmailCollection() {
	var email = document.getElementById('email');
	var sendFlag = true;
	
	if (email.value.Trim() == "" && sendFlag){
		alert("Please input your email address");
		sendFlag = false;
		email.focus();
	} else if (!checkMail(email.value.Trim()) && sendFlag) {
		alert("Invalid email format. Please input again");
		sendFlag = false;
		email.focus();
	}
	
	if (sendFlag)
		myForm.btnSubmit.disabled = "disabled";
	
	return sendFlag;
}