var _year_obj_ = new Array(), _month_obj_ = new Array(), _day_obj_ = new Array();

function is_leap(year){
	if(year%400==0) return true;
	else if(year%100==0) return false;
	else if(year%4==0) return true;
	else return false;
}

function calanderChange(idx){
	if(idx==null){
		idx = 0;
		while(
			_year_obj_[idx]!=event.srcElement&&
			_month_obj_[idx]!=event.srcElement
		) if(++idx>_year_obj_.length) return;
	}
	if(_year_obj_[idx].selectedIndex < 0) return;
	if(_month_obj_[idx].selectedIndex < 0) return;
	var days = new Array(31,28,31,30,31,30,31,31,30,31,30,31);
	var year = _year_obj_[idx].options(_year_obj_[idx].selectedIndex).text;
	var month = _month_obj_[idx].selectedIndex + 1;
	var day = _day_obj_[idx].selectedIndex + 1;
	var day_num = (month==2&&is_leap(year))? 29 : days[month-1];
	while(_day_obj_[idx].length < day_num){
		var objEntry = document.createElement("OPTION");
		objEntry.text=(_day_obj_[idx].length + 1);
		_day_obj_[idx].add(objEntry);
	}
	while(_day_obj_[idx].length > day_num)
		_day_obj_[idx].remove(_day_obj_[idx].length-1);
	_day_obj_[idx].selectedIndex = (day > day_num)? day_num-1:day-1;
}

function initClock(hour, minute, init){
	var hobj = document.all(hour);
	var mobj = document.all(minute);
	while(hobj.length > 0) hobj.remove(0);
	for(var i = 0; i < 24; i++){
		var tmp_i = i<10? "0"+i:i;
		var objEntry = document.createElement("OPTION");
		objEntry.text = tmp_i;
		hobj.add(objEntry);
	}
	while(mobj.length > 0) mobj.remove(0);
	for(var i = 0; i < 60; i++){
		var tmp_i = i<10? "0"+i:i;
		var objEntry = document.createElement("OPTION");
		objEntry.text = tmp_i;
		mobj.add(objEntry);
	}
  if(init==null) init = new Date();
  hobj.selectedIndex = init.getHours();
  mobj.selectedIndex = init.getMinutes();
}

function initYear(year, start, end, target){
	var yobj = document.all(year);
	while(yobj.length > 0) yobj.remove(0);
	for(var i = start; i<=end; i++){
		var objEntry = document.createElement("OPTION");
		objEntry.text = i;
		yobj.add(objEntry);
	}
	var cur_year = target==null ? new Date().getYear():target;
	yobj.selectedIndex = (cur_year>=start&&cur_year<=end)? cur_year-start:-1;
}

function initCalander(name, start, end, init){
	var year = name + "_year";
	var month = name + "_month";
	var day = name + "_day";
	idx = _year_obj_.length;
	_year_obj_[idx] = document.all(year);
	_month_obj_[idx] = document.all(month);
	_day_obj_[idx] = document.all(day);

	while(_year_obj_[idx].length > 0) _year_obj_.remove(0);
	for(var i = start; i<=end; i++){
		var objEntry = document.createElement("OPTION");
		objEntry.text=i;
		_year_obj_[idx].add(objEntry);
	}
	while(_month_obj_[idx].length > 0) _month_obj_.remove(0);
	for(var i=1;i<=12;i++){
		var tmp_i = i<10? "0"+i:i;
		var objEntry = document.createElement("OPTION");
		objEntry.text=tmp_i;
		_month_obj_[idx].add(objEntry);
	}
	while(_day_obj_[idx].length > 0) _day_obj_.remove(0);
	for(var i=1;i<=31;i++){
		var tmp_i = i<10? "0"+i:i;
		var objEntry = document.createElement("OPTION");
		objEntry.text=tmp_i;
		_day_obj_[idx].add(objEntry);
	}
	_year_obj_[idx].onchange=calanderChange;
	_month_obj_[idx].onchange=calanderChange;
	if(init==null) init = new Date();
	if(init.getFullYear()>=start&&init.getFullYear()<=end){
		_year_obj_[idx].selectedIndex = init.getFullYear()-start;
		_month_obj_[idx].selectedIndex = init.getMonth();
		_day_obj_[idx].selectedIndex = init.getDate()-1;
	}else{
		_year_obj_[idx].selectedIndex = -1;
		_month_obj_[idx].selectedIndex = -1;
		_day_obj_[idx].selectedIndex = -1;
	}
	calanderChange(idx);
}