var calc_doc;

function getCalcDoc()
{
	return calc_doc;
}

function showCalendarHere(str_target, str_datetime)
{
	window.opener.getCalcDoc().getElementById('cont').innerHTML = getData( str_target, str_datetime );
}

function getData( str_target, str_datetime )
{
	var arr_months = ["Styczeń", "Luty", "Marzec", "Kwiecień", "Maj", "Czerwiec",
		"Lipiec", "Sierpień", "Wrzesień", "Padziernik", "Listopad", "Grudzień"];
	var week_days = ["Nd", "Pon", "Wt", "Śr", "Czw", "Pt", "Sob"];
	var n_weekstart = 1; // day week starts from (normally 0 or 1)

	var dt_datetime = (str_datetime == null || str_datetime =="" ?  new Date() : str2dt(str_datetime));
	var dt_prev_month = new Date(dt_datetime);
	dt_prev_month.setMonth(dt_datetime.getMonth()-1);
	var dt_next_month = new Date(dt_datetime);
	dt_next_month.setMonth(dt_datetime.getMonth()+1);
	var dt_firstday = new Date(dt_datetime);
	dt_firstday.setDate(1);
	dt_firstday.setDate( 1 - ( 7 + dt_firstday.getDay() - n_weekstart ) %7 );
	var dt_lastday = new Date(dt_next_month);
	dt_lastday.setDate(0);
	
	// html generation (feel free to tune it for your particular application)
	// print calendar header
	var str_buffer = new String (
		"<table class=\"clsOTable\" cellspacing=\"0\" border=\"0\" width=\"100%\">\n"+
		"<tr><td bgcolor=\"#4682B4\">\n"+
		"<table cellspacing=\"1\" cellpadding=\"3\" border=\"0\" width=\"100%\">\n"+
		"<tr>\n	<td bgcolor=\"#4682B4\"><a href=\"#\" onClick=\"showCalendarHere('"+
		str_target+"', '"+ dt2dtstr(dt_prev_month)+"');return false;\">"+
		"<img src=\""+baseHr+"html/gfx/calendar/prev.gif\" width=\"16\" height=\"16\" border=\"0\""+
		" alt=\"previous month\"></a></td>\n"+
		"	<td bgcolor=\"#4682B4\" colspan=\"5\">"+
		"<font color=\"white\" face=\"tahoma, verdana\" size=\"2\">"
		+arr_months[dt_datetime.getMonth()]+" "+dt_datetime.getFullYear()+"</font></td>\n"+
		"	<td bgcolor=\"#4682B4\" align=\"right\"><a href=\"#\" onClick=\"showCalendarHere('"
		+str_target+"', '"+dt2dtstr(dt_next_month)+"');return false;\">"+
		"<img src=\""+baseHr+"html/gfx/calendar/next.gif\" width=\"16\" height=\"16\" border=\"0\""+
		" alt=\"next month\"></a></td>\n</tr>\n"
	);

	var dt_current_day = new Date(dt_firstday);
	// print weekdays titles
	str_buffer += "<tr>\n";
	for (var n = 0; n < 7; n++)
		str_buffer += "	<td bgcolor=\"#87CEFA\">"+
		"<font color=\"white\" face=\"tahoma, verdana\" size=\"2\">"+
		week_days[(n_weekstart+n)%7]+"</font></td>\n";
	// print calendar table
	str_buffer += "</tr>\n";
	while (dt_current_day.getMonth() == dt_datetime.getMonth() ||
		dt_current_day.getMonth() == dt_firstday.getMonth()) {
		// print row heder
		str_buffer += "<tr>\n";
		for (var n_current_wday=0; n_current_wday<7; n_current_wday++) {
				if (dt_current_day.getDate() == dt_datetime.getDate() &&
					dt_current_day.getMonth() == dt_datetime.getMonth())
					// print current date
					str_buffer += "	<td bgcolor=\"#FFB6C1\" align=\"right\">";
				else if (dt_current_day.getDay() == 0 || dt_current_day.getDay() == 6)
					// weekend days
					str_buffer += "	<td bgcolor=\"#DBEAF5\" align=\"right\">";
				else
					// print working days of current month
					str_buffer += "	<td bgcolor=\"white\" align=\"right\">";

				if (dt_current_day.getMonth() == dt_datetime.getMonth())
					// print days of current month
					str_buffer += "<a href=\"javascript:window.opener."+str_target+
					".value='"+dt2dtstr(dt_current_day)+"'; window.close();\">"+
					"<font color=\"black\" face=\"tahoma, verdana\" size=\"2\">";
				else 
					// print days of other months
					str_buffer += "<a href=\"javascript:window.opener."+str_target+
					".value='"+dt2dtstr(dt_current_day)+"'; window.close();\">"+
					"<font color=\"gray\" face=\"tahoma, verdana\" size=\"2\">";
				str_buffer += dt_current_day.getDate()+"</font></a></td>\n";
				dt_current_day.setDate(dt_current_day.getDate()+1);
		}
		// print row footer
		str_buffer += "</tr>\n";
	}
	// print calendar footer
	str_buffer +=
		"</table>\n" +
		"</tr>\n</td>\n</table>\n";
		
	return str_buffer;
}

function show_calendar_second(str_target, str_datetime)
{
	var vWinCal = window.open(null, null, "width=200,height=200,status=0,resizable=0,top=200,left=200,titlebar=0,menubar=0,toolbar=0,location=0");
	calc_doc = vWinCal.document;
	
	var str_buffer = "<html>\n<head>\n<title>Kalendarz</title>\n<script language=\"JavaScript\" src=\""+baseHr+"html/js/calendar.js\"></script></head>\n<body bgcolor=\"White\">\n<div id='cont'>";
	str_buffer += getData( str_target, str_datetime, calc_doc );
	str_buffer +=  "</div></body>\n</html>\n";
	
	calc_doc.write (str_buffer);
	calc_doc.close();
}

function show_calendar(str_target, str_datetime)
{
	var vWinCal = window.open(null, null, "width=200,height=200,status=0,resizable=0,top=200,left=200,titlebar=0,menubar=0,toolbar=0,location=0");
	vWinCal.opener = self;
	var calc_doc = vWinCal.document;
	self.calc_doc = vWinCal.document;
	
	var str_buffer = "";
	str_buffer +=  "<html>\n<head><script>var baseHr='"+baseHr+"'</script>\n<title>Kalendarz</title>\n<script language=\"JavaScript\" src=\""+baseHr+"html/js/calendar.js\"></script></head>\n<body bgcolor=\"White\">\n<div id='cont'>";
	str_buffer += getData( str_target, str_datetime, calc_doc );
	str_buffer +=  "</div></body>\n</html>\n";
	
	calc_doc.write (str_buffer);
	calc_doc.close();
}
// datetime parsing and formatting routimes. modify them if you wish other datetime format
function str2dt (str_datetime) {
	var re_date = /^(\d+)\-(\d+)\-(\d+)$/;
	if (!re_date.exec(str_datetime))
		return alert("Nieprawidowy format daty: "+ str_datetime);
	return (new Date (RegExp.$3, RegExp.$2-1, RegExp.$1));
}
function dt2dtstr (dt_datetime) {
	return (new String (
			dt_datetime.getDate()+"-"+(dt_datetime.getMonth()+1)+"-"+dt_datetime.getFullYear()));
}

function next_day()
{
	if(document.form.data.value != '')
	{
		var next_day = str2dt(document.form.data.value);
		next_day.setDate(next_day.getDate()+1);
		document.form.data.value = dt2dtstr(next_day);
	}
}

function prev_day()
{
	if(document.form.data.value != '')
	{
		var next_day = str2dt(document.form.data.value);
		next_day.setDate(next_day.getDate()-1);
		document.form.data.value = dt2dtstr(next_day);
	}
}

function next_day2()
{
	if(document.form.data2.value != '')
	{
		var next_day = str2dt(document.form.data2.value);
		next_day.setDate(next_day.getDate()+1);
		document.form.data2.value = dt2dtstr(next_day);
	}
}

function prev_day2()
{
	if(document.form.data2.value != '')
	{
		var next_day = str2dt(document.form.data2.value);
		next_day.setDate(next_day.getDate()-1);
		document.form.data2.value = dt2dtstr(next_day);
	}
}

function str2time (str_datetime) {
	var re_date = /^(\d+)\-(\d+)\-(\d+)-(\d+)$/;
	if (!re_date.exec(str_datetime))
		return;
		
	return (new Date (RegExp.$4, RegExp.$3-1, RegExp.$2, RegExp.$1));
}


function prev_hour()
{
	var hour = parseInt(document.form.hour.value)
	
	if(document.form.hour.value != '' && hour > 0)
	{
		var prev_hour = hour - 1;
		document.form.hour.value = prev_hour;
	}
	
	if(document.form.hour.value != '' && hour == 0)
	{
		document.form.hour.value = 23;
	}
}

function next_hour()
{
	var hour = parseInt(document.form.hour.value)
	
	if(document.form.hour.value != '' && hour < 23)
	{
		var next_hour = hour + 1;
		document.form.hour.value = next_hour;
	}
	
	if(document.form.hour.value != '' && hour == 23)
	{
		document.form.hour.value = 'z00';
	}
}

function prev_hour2()
{
	var hour = parseInt(document.form.hour2.value)
	
	if(document.form.hour2.value != '' && hour > 0)
	{
		var prev_hour = hour - 1;
		document.form.hour2.value = prev_hour;
	}
	
	if(document.form.hour2.value != '' && hour == 0)
	{
		document.form.hour2.value = 23;
	}
}

function next_hour2()
{
	var hour = parseInt(document.form.hour2.value)
	
	if(document.form.hour2.value != '' && hour < 23)
	{
		var next_hour = hour + 1;
		document.form.hour2.value = next_hour;
	}
	
	if(document.form.hour2.value != '' && hour == 23)
	{
		document.form.hour2.value = 'z00';
	}
}