var jSelectDate = {	
	/**
	 * 选项设置
	 */
    settings : {
		css: "date",
		borderCss: "date",
        disabled: false,
        yearBegin: new Date().getFullYear()-90,
        yearEnd: new Date().getFullYear()-18,
		isShowLabel: true,
		language:"en-us"
	},   
    /**
     * 初始化对向
     * @param {Object} el 用于存放日期结果的文本框 jQuery DOM
     */
    init: function(els){    
        els.each(function(){  
            var el = $(this);            
            /* 取得旧的日期 */
            var elValue = el.val();
            elDate = new Date(elValue.split("-").join("/"));            
            var nYear = elDate.getFullYear();
            var nMonth = jSelectDate.returnMonth(elDate.getMonth());
            var nDay = elDate.getDate();           
            /* 隐藏给出的对向 */
            el.hide();            
            /* 先算出当前共有多少个jSelectDate */
            var currentIdx = $("jSelectDateBorder").length + 1;			
             /* 加入控件到文本框的位置 */
			var spanDate = document.createElement("span");
			spanDate.id = "spanDate" + currentIdx;
			spanDate.className = "jSelectDateBorder " + jSelectDate.settings.borderCss;
			spanDate.disabled = jSelectDate.settings.disabled;			
            el.after(spanDate);			
            var ymd;
            switch(jSelectDate.settings.language){
                case "zh-cn":ymd=new Array('-年-','-月-','-日-');break;
                case "en-us":ymd=new Array('-Year-','-Month-','-Day-');break;
                default:ymd=new Array('-年-','-月-','-日-');break;
            };
                     
//			$(spanDate).append(selYear);            
            /* 创建月 */
            var selMonth = document.createElement("select");
            selMonth.id = "selMonth" + currentIdx
			selMonth.className = jSelectDate.settings.css;
            selMonth.disabled = jSelectDate.settings.disabled;
            /* 加入选项 */
            var optionm = document.createElement("option");
                optionm.innerHTML =ymd[1] ; 
                selMonth.appendChild(optionm);  
                optionm=null;
            for (var i = 1; i <= 12; i++) {
                var option = document.createElement("option");
                option.value = i;
                option.innerHTML = i;                
                /* 判断是否有旧的值，如果有就选中 */
                if (!isNaN(nMonth)) {
                    if (i == nMonth) {
                        option.selected = true;
                    }
                }                
                selMonth.appendChild(option);
                option = null;
            }
            /* 加入控件到文本框的位置 */
            $(spanDate).append(selMonth);
//            $(selYear).after(selMonth);           
            /* 创建日 */           
            var selDay = document.createElement("select");
            selDay.id = "selDay" + currentIdx
			selDay.className = jSelectDate.settings.css;
            selDay.disabled = jSelectDate.settings.disabled;            
			/* 算出最大的天数 */			
			var maxDayNum = 30;
			if (nMonth == 2) {
				if (jSelectDate.isLeapYear(nYear)) {
					maxDayNum = 29;
				}
				else{
					maxDayNum = 28;
				}
			}
			else if (jSelectDate.isLargeMonth(nMonth)) {
					maxDayNum = 31;
			}			
			/* 加入选项 */
			 var optiond = document.createElement("option");
//                optiond.value = 0;
                optiond.innerHTML =ymd[2] ; 
                selDay.appendChild(optiond);  
                optiond=null;
            for (var i = 1; i <= maxDayNum; i++) {            
                var option = document.createElement("option");
                option.value = i;
                option.innerHTML = i;                
                /* 判断是否有旧的值，如果有就选中 */
                if (!isNaN(nDay)) {
                    if (i == nDay) {
                        option.selected = true;
                    }
                }                
                selDay.appendChild(option);
                option = null;
            }
            /* 加入控件到文本框的位置 */
            $(selMonth).after(selDay);   
            /* 创建年 */
            var selYear = document.createElement("select");
            selYear.id = "selYear" + currentIdx
            selYear.className = jSelectDate.settings.css;
            selYear.disabled = jSelectDate.settings.disabled;            
            /* 加入选项 */
            var optiony = document.createElement("option");
                optiony.innerHTML =ymd[0] ; 
                selYear.appendChild(optiony);  
                optionm=null;
            for (var i = jSelectDate.settings.yearEnd; i >= jSelectDate.settings.yearBegin; i--) {            
                var option = document.createElement("option");
                option.value = i;
                option.innerHTML = i;                
                /* 判断是否有旧的值，如果有就选中 */
                if (!isNaN(nYear)) {
                    if (i == nYear) {
                        option.selected = true;
                    }
                }                
                selYear.appendChild(option);
                option = null;                
            }  
            $(selDay).after(selYear);          				
            /* 返回当前选择的日期 */
            var getDate = function(){
                var year = $(selYear).val();
                var month = $(selMonth).val();
                var day = $(selDay).val();
                el.val(year + "-" + month + "-" + day);
            }		
            /**
             * 给几个下拉列表加入更改后的事件
             */
            $(selDay).change(function(){
                return getDate();
            });
            $(selMonth).change(function(){				
				jSelectDate.progressDaySize(this,true);
				/* 更新文本框中的日期 */
                return getDate();
            });
            $(selYear).change(function(){
				jSelectDate.progressDaySize(this,false);
                return getDate();
            });
            
        })        
    },	
	/**
	 * 判断是否闰年
	 * @param {Object} year
	 */
	isLeapYear : function(year){ 
　　	return (0==year%4&&((year%100!=0)||(year%400==0)));
　　},
	/**
	 * 判断是否是大月
	 * @param {Object} monthNum
	 */
	isLargeMonth : function(monthNum){
		var largeArray = [true,false,true,false,true,false,true,true,false,true,false,true];
		return largeArray[monthNum - 1];
	},    
    returnMonth: function(num){
        var arr = new Array("1", "2", "3", "4", "5", "6", "7", "8", "9", "10", "11", "12");
        return arr[num];
    },
	/**
	 * 创建一个Option对象
	 * @param {Object} value 值
	 * @param {Object} text 文本
	 */
	createOption : function(value,text){
		var option = document.createElement("option");
        option.value = value;
        option.innerHTML = text;
		return option;			
	},
	/**
	 * 处理天数
	 * @param {Object} el 下拉列表对像
	 * @param {Object} isMonth 是否是月的下拉列表 或者就处理 年的下拉列表
	 */
	progressDaySize: function(el,isMonth){
		if (isMonth == true) {
			/* 选择月时处理大月、小月和二月的情况 */
			var month = $(el).val();
			var year = $($("select", $(el).parent())[2]).val()
			var selDay = $($("select", $(el).parent())[1]);
			if (month == 2) {			
				/* 2月处理 */
				$("option:contains('31')", selDay).remove();
				$("option:contains('30')", selDay).remove();				
				/* 闰年处理 */
				if (!jSelectDate.isLeapYear(year)) {
					$("option:contains('29')", selDay).remove();
				}
				else {				
					if ($("option:contains('29')", selDay).length == 0) {
						selDay.append(jSelectDate.createOption(29, 29));
					}
				}
			}
			else 
				if (!jSelectDate.isLargeMonth(month)) {				
					/* 小月处理 */
					if ($("option:contains('30')", selDay).length == 0) {
						selDay.append(jSelectDate.createOption(30, 30));
					}					
					$("option:contains('31')", selDay).remove();
				}
				else {				
					/* 大月处理 */
					if ($("option:contains('30')", selDay).length == 0) {
						selDay.append(jSelectDate.createOption(30, 30));
					}					
					if ($("option:contains('31')", selDay).length == 0) {
						selDay.append(jSelectDate.createOption(31, 31));
					}
				}
		}
		else{
			/* 处理闰年的二月问题 */
			var panelDate = $(el).parent();
			var year = $(el).val();
			var month = $($("select",panelDate)[0]).val()
			var selDay = $($("select",panelDate)[1]);
			if(month == 2){
				$("option:contains('31')",selDay).remove();
				$("option:contains('30')",selDay).remove();
				if(! jSelectDate.isLeapYear(year)){				
					$("option:contains('29')",selDay).remove();
				}
				else{
					
					if($("option:contains('29')",selDay).length == 0){
						selDay.append(jSelectDate.createOption(29, 29));
					}
				}
			}			
		}
	}    
}
jQuery.fn.jSelectDate = function(settings){   
	var getNowYear = function(){
        /* 得到现在的年 */
        var date = new Date();
        return date.getFullYear();
    }
    jSelectDate.settings.yearEnd = getNowYear() - 18;
    jSelectDate.settings.yearBeign = getNowYear() - 90;	
    $.extend(jSelectDate.settings, settings);
    jSelectDate.init($(this));    
    return $(this);    
}