/*utility.js
 * based on mootools v1.0
 * wirtten by easy.lv
 * some useful extention
 */
 
 
/*
 * Responsebility : count the num you have inputed or the num you can input now in one input area
 * 
 * count_container_id: your input area id 
 * showtype: 1:show the num now;2: show the num left to the maxnum
 * maxunm:if your showtype=2,this is the max num you can input into the input area
 * fill_container_id:the area you want to show the text about the num or the num left
 */ 
var Count_input_num = function(count_container_id,showtype,maxnum,fill_container_id,ChineseWordsLength,baseon)
{
	if(typeof count_container_id == 'string'){
		this.ccid = $(count_container_id);
	}else{
		this.ccid = count_container_id;
	}
	
	if(typeof fill_container_id == 'string'){
		this.fcid = $(fill_container_id);
	}else{
		this.fcid = fill_container_id;
	}
	
	this.showtype = showtype;
	this.maxnum = maxnum;
	if(ChineseWordsLength=='')
	{
		ChineseWordsLength = 2;
	}
	this.ChineseWordsLength = ChineseWordsLength;
	this.ccid.maxlength = this.maxnum;
	this.count();
	if(baseon = 'prototype')
	{
		this.ccid.onkeyup = this.count.bindAsEventListener(this);	
	}else
	{
		this.ccid.onkeyup = this.count.bindWithEvent(this);
	}
};

Count_input_num.prototype.count = function()
{
	var replaceword = '';
	for(var i=0;i<this.ChineseWordsLength;i++)
	{
		replaceword = replaceword + '*';
	}
	this.num = this.ccid.value.replace(/[^\x00-\x80]/ig,replaceword).length;
	if(this.showtype == 2)
	{
		this.left = this.maxnum - this.num;
	}
	this.showresult();
};

Count_input_num.prototype.showresult = function()
{
	if(this.fcid=='')
	{
		return;
	}
	if(this.showtype == 1)
	{
		var str = '現在已經輸入'+this.num+'字符';
		if(this.ChineseWordsLength>1) str+='（1個漢字等于'+this.ChineseWordsLength+'個字符）';
		this.fcid.innerHTML = str;
	}
	if(this.showtype == 2)
	{
		if(this.left<0)
		{	
			this.fcid.style.color = "#D50000";
			var str = '還可以輸入'+this.left+'字符';
			if(this.ChineseWordsLength>1) str+='（1個漢字等于'+this.ChineseWordsLength+'個字符）';
			str += '，超過最大長度';
			this.fcid.innerHTML = str;
		}else
		{
			this.fcid.style.color = "#999999";
			var str = '還可以輸入'+this.left+'字符';
			if(this.ChineseWordsLength>1) str+='（1個漢字等于'+this.ChineseWordsLength+'個字符）';
			this.fcid.innerHTML = str;
		}
	}
}