//var dateselect_default_year = 2012;
var dateselect_start_date = new Date('2012/9/6');
var dateselect_start_month = new Date('2012/9/1');
var dateselect_default_year = dateselect_start_date.getYear();
if (dateselect_default_year < 1900) dateselect_default_year += 1900;
var currently_year = 2024;
var currently_month = 5;
var currently_day = 4;
var currently_date = new Date(currently_year+'/'+currently_month+'/'+currently_day)
var dateselect_end_year = currently_date.getYear();
if (dateselect_end_year < 1900) dateselect_end_year += 1900;

//elements names
var dateselect_yearElementsId = "ご購入日（年）";
var dateselect_monthElementsId = "ご購入日（月）";
var dateselect_dayElementsId = "ご購入日（日）";
var dateselect_calendars = new Array(0,31,28,31,30,31,30,31,31,30,31,30,31);
var dateselect_monthName = new Array('1','2','3','4','5','6','7','8','9','10','11','12');
var dateselect_weeksName = new Array('日','月','火','水','木','金','土');

function dateselect_getWeek(year,month,day){
	year = parseInt(year);
	month = parseInt(month);
	day = parseInt(day);
	if(month == 1 || month == 2) {
		year--;
		month += 12;
	}
	week = Math.floor(year + Math.floor(year/4) - Math.floor(year/100) + Math.floor(year/400) + Math.floor((13 * month + 8) / 5) + day) % 7;
	return week;
}
function dateselect_bissextile(year,month){
	//year = parseInt(year);
	//month = parseInt(month);
	var dateselect_calendars = new Array(0,31,28,31,30,31,30,31,31,30,31,30,31);
	var cal_flag = 0;
	if(year % 100 == 0 || year % 4 != 0){
		if(year % 400 != 0){
			cal_flag = 0;
		}
		else{
			cal_flag = 1;
		}
	}
	else if(year % 4 == 0){
		cal_flag = 1;
	}
	else{
		cal_flag = 0;
	}
	dateselect_calendars[2] += cal_flag;
	return dateselect_calendars[month];
}
function dateselect_change(formId,yearEle,monthEle,dayEle,obj){
	if(obj.id == yearEle){
		document.getElementById(monthEle).selectedIndex = 0;
		document.getElementById(dayEle).selectedIndex = 0;
	}
	else if(obj.id == monthEle){
		document.getElementById(dayEle).selectedIndex = 0;
	}
	dateselect_yearElementsId = yearEle;
	dateselect_monthElementsId = monthEle;
	dateselect_dayElementsId = dayEle;
	yearObj = document.forms[formId].elements[dateselect_yearElementsId];
	monthObj = document.forms[formId].elements[dateselect_monthElementsId];
	dayObj = document.forms[formId].elements[dateselect_dayElementsId];
	var dateselect_year = yearObj.value;
	var dateselect_month = monthObj.value;
	var dateselect_day = dayObj.value;
	
	if(yearObj.value == "")
		document.getElementById('label_'+dateselect_monthElementsId).style.display = 'none';
	else
		document.getElementById('label_'+dateselect_monthElementsId).style.display = 'block';
	
	if(monthObj.value == "")
		document.getElementById('label_'+dateselect_dayElementsId).style.display = 'none';
	else
		document.getElementById('label_'+dateselect_dayElementsId).style.display = 'block';
	
	if(yearObj.value != ""){
		//day
		if(dateselect_month == "")
			dateselect_month = 1;
		
		dateselect_week = dateselect_getWeek(dateselect_year,dateselect_month,1);
		dayObj.length = dateselect_bissextile(dateselect_year,dateselect_month)+1;
		
		var MonthLength = 1;
		monthObj.length = 32;
		
		monthObj.options[0].value = "";
		monthObj.options[0].text = '選択してください';
		for(var i=0;i<12;i++){
			var ChkDate = new Date(yearObj.value+'/'+(i+1)+'/1');
			if(dateselect_start_month.getTime() <= ChkDate.getTime() && ChkDate.getTime() < currently_date.getTime()){
				MonthLength++;
				//monthObj.length = MonthLength;
				monthObj.options[MonthLength-1].value = i+1;
				monthObj.options[MonthLength-1].text = dateselect_monthName[i];
			}
		}
		monthObj.length = MonthLength;
		
		dayObj.options[0].value = "";
		dayObj.options[0].text = '選択してください';
		var dayLength = 1;
		for(var i=1;i<dayObj.length;i++){
			var ChkDate = new Date(yearObj.value+'/'+monthObj.value+'/'+i);
			if(dateselect_start_date.getTime() <= ChkDate.getTime() && ChkDate.getTime() <= currently_date.getTime()){
				var print_day = i;
				if(print_day < 10)
					print_day = "0" + i;
				dayObj.options[dayLength].value = i;
				dayObj.options[dayLength].text = i;
				dayLength++;
			}
			dateselect_week++;
			if(dateselect_week > 6){
				dateselect_week = 0;
			}
		}
		dayObj.length = dayLength;
	}
	else {
		yearObj.value = "";
		monthObj.length = 0;
		monthObj.value = "";
		dayObj.length = 0;
		dayObj.value = "";
	}
}
var dateselect_today = new Date();
var dateselect_year = dateselect_today.getYear();
var dateselect_month = dateselect_today.getMonth();
var dateselect_day = dateselect_today.getDate();
if (dateselect_year < 1900) dateselect_year += 1900;


//year
document.write('<div id="label_'+dateselect_yearElementsId+'"><select id="'+dateselect_yearElementsId+'" name="'+dateselect_yearElementsId+'" required="required" onchange="dateselect_change(this.form.id,'+"'"+dateselect_yearElementsId+"',"+"'"+dateselect_monthElementsId+"',"+"'"+dateselect_dayElementsId+"'"+',this)">');
document.write('<option value="">選択してください</option>');
for(i=0;(i+dateselect_default_year)<=dateselect_end_year;i++){
	var print_year = dateselect_default_year + i;
	document.write('<option value="'+print_year+'">'+print_year+'</option>');
}
document.write('</select> 年</div>');

//month
document.write('<div id="label_'+dateselect_monthElementsId+'"><select id="'+dateselect_monthElementsId+'" name="'+dateselect_monthElementsId+'" required="required" onchange="dateselect_change(this.form.id,'+"'"+dateselect_yearElementsId+"',"+"'"+dateselect_monthElementsId+"',"+"'"+dateselect_dayElementsId+"'"+',this)">');
document.write('<option value="">選択してください</option>');
document.write('</select> 月</div>');

//day
var dateselect_week = dateselect_getWeek(dateselect_year,dateselect_month+1,1);
document.write('<div id="label_'+dateselect_dayElementsId+'"><select id="'+dateselect_dayElementsId+'" required="required" name="'+dateselect_dayElementsId+'">');
document.write('<option value="'+dateselect_dayElementsId+'">選択してください</option>');
document.write('</select> 日</div>');

//dateselect_change('mailformpro',dateselect_yearElementsId,dateselect_monthElementsId,dateselect_dayElementsId,document.getElementById(dateselect_yearElementsId));