// months as they appear in the calendar's title
var ARR_MONTHS = ["January", "February", "March", "April", "May", "June",
		"July", "August", "September", "October", "November", "December"];
// week day titles as they appear on the calendar
var ARR_WEEKDAYS = ["s", "m", "t", "w", "t", "f", "s"];
// day week starts from (normally 0-Su or 1-Mo)
var NUM_WEEKSTART = 0;
// path to the directory where calendar images are stored. trailing slash req.
var STR_ICONPATH = 'img/';

var re_urlCur = new RegExp('c=(\\-?\\d+)');
var re_urlSel = new RegExp('s=(\\-?\\d+)');
var re_id = new RegExp('id=(\\d+)');

var dt_selected = (re_urlSel.exec(String(window.location))
	? new Date(new Number(RegExp.$1)) : new Date());
var dt_current = (re_urlCur.exec(String(window.location))
	? new Date(new Number(RegExp.$1)) : dt_selected);
var num_id = (re_id.exec(String(window.location))
	? new Number(RegExp.$1) : 0);

var obj_caller = (window.opener ? window.opener.calendars[num_id] : null);

if (obj_caller && obj_caller.year_scroll) {
	// get same date in the previous year
	var dt_prev_year = new Date(dt_current);
	dt_prev_year.setFullYear(dt_prev_year.getFullYear() - 1);
	if (dt_prev_year.getDate() != dt_current.getDate())
		dt_prev_year.setDate(0);
	
	// get same date in the next year
	var dt_next_year = new Date(dt_current);
	dt_next_year.setFullYear(dt_next_year.getFullYear() + 1);
	if (dt_next_year.getDate() != dt_current.getDate())
		dt_next_year.setDate(0);
}

// get same date in the previous month
var dt_prev_month = new Date(dt_current);
if (dt_prev_month.getMonth()) {
	dt_prev_month.setMonth(dt_prev_month.getMonth() - 1);
	if (dt_prev_month.getDate() != dt_current.getDate())
		dt_prev_month.setDate(0);
}
else {
	dt_prev_month.setFullYear(dt_prev_month.getFullYear() - 1);
	dt_prev_month.setMonth(11);
}

// get same date in the next month
var dt_next_month = new Date(dt_current);
dt_next_month.setMonth(dt_next_month.getMonth() + 1);
if (dt_next_month.getDate() != dt_current.getDate())
	dt_next_month.setDate(0);

// get first day to display in the grid for current month
var dt_firstday = new Date(dt_current);
dt_firstday.setDate(1);
dt_firstday.setDate(1 - (7 + dt_firstday.getDay() - NUM_WEEKSTART) % 7);

// function passing selected date to calling window
function set_datetime(n_datetime, b_close) {
	if (!obj_caller) return;

	var dt_datetime = obj_caller.prs_time(
		(document.cal ? document.cal.time.value : ''),
		new Date(n_datetime)
	);

	if (!dt_datetime) return;
	if (b_close) {
		
		obj_caller.target.value = (document.cal
			? obj_caller.gen_tsmp(dt_datetime)
			: obj_caller.gen_date(dt_datetime)
		);window.close();
	}
	else obj_caller.popup(dt_datetime.valueOf());
}


function showCalendar()
{
	// print weekdays titles
	for (var n=0; n<7; n++)
		document.write('<td class="daysHeader">'+ARR_WEEKDAYS[(NUM_WEEKSTART+n)%7]+'</td>');
	document.write('</tr>');

	// print calendar table
	var dt_current_day = new Date(dt_firstday);
	while (dt_current_day.getMonth() == dt_current.getMonth() ||
		dt_current_day.getMonth() == dt_firstday.getMonth()) {
		// print row heder

		document.write('<tr>');
		for (var n_current_wday=0; n_current_wday<7; n_current_wday++) {
			if (dt_current_day.getDate() == dt_selected.getDate() &&
				dt_current_day.getMonth() == dt_selected.getMonth() &&
				dt_current_day.getFullYear() == dt_selected.getFullYear())
				// print current date
				document.write('<td class="selectedDay" align="center" >');
			else 
				// print working days of current month
				document.write('<td class="day" align="center" >');

			if (dt_current_day.getMonth() == this.dt_current.getMonth())
				// print days of current month
				document.write('<span class="currentMonthDay">');
			else 
				// print days of other months
				document.write('<span class="otherMonthDay">');
				
			document.write(dt_current_day.getDate()+'</span></td>');
			dt_current_day.setDate(dt_current_day.getDate()+1);
		}
		// print row footer
		document.write('</tr>');
	}
	if (obj_caller && obj_caller.time_comp) {
		document.write('<form onsubmit="javascript:set_datetime('+dt_current.valueOf()+', true)" name="cal"><tr><td colspan="7" bgcolor="#87CEFA"><font color="White" face="tahoma, verdana" size="2">Time: <input type="text" name="time" value="'+obj_caller.gen_time(this.dt_current)+'" size="8" maxlength="8"></font></td></tr></form>');
		document.forms['cal'].elements['time'].focus();
	}
}