// JavaScript Document

var transferfee = 500;
var hkpostrate = 1200;
var hkpostrate_abs = 600;

function getTransferfee()
{
	document.write(transferfee);
}

function getHKPostFee(weight)
{
	var hkpostfee;
	
	if (weight < 1)
		hkpostfee = hkpostrate_abs;
	else
		hkpostfee = weight * hkpostrate;
		
	return hkpostfee;
}

function changeHKPostFee(weight)
{
	document.getElementById("displayhkpostfee").innerHTML = getHKPostFee(weight);
	document.getElementById("hkPostFee").value = getHKPostFee(weight);
}

function validate(theForm)
{
	var errMsg = "";
	
	if ( isEmpty(theForm.price.value) )
		errMsg += "- 請填上貨品金額\n";
	else if ( !isFloatNumber(theForm.price.value) )
		errMsg += "- 貨品金額不是正數\n";

	if ( !isEmpty(theForm.postfee.value) &&　!isFloatNumber(theForm.postfee.value)　)
		errMsg += "- 當地郵費不是正數\n";
		

	if ( isEmpty(errMsg) )
		return true;
	else
	{
		alert("請修改以下問題:\n" + errMsg);
		return false;
	}
}

function clearValues()
{
	document.getElementById("price").value = "";
	document.getElementById("postfee").value = "1000";
	document.myform.charged[2].checked = true;
	document.myform.weight[0].selected = true;
	changeHKPostFee(document.myform.weight.value);
}