// Die standard Defaults, können beim Initialisieren überschrieben werden
var A_TCALDEF = {
	'months' : [ 'Januar', 'Februar', 'März', 'April', 'May', 'Juni', 'Juli',
			'August', 'September', 'Oktober', 'November', 'Dezember' ],
	'weekdays' : [ 'So', 'Mo', 'Di', 'Mi', 'Do', 'Fr', 'Sa' ],
	'yearscroll' : true, // Zeige Jahresscroller
	'weekstart' : 1, // Erster Tag der Woche: 0-So or 1-Mo
	'centyear' : 70, // für 2 Stellige Jahreszahl ab 1970
	'imgpath' : 'jsp/include/global/images/calendar/' // Verzeichnis mit den Images
}
// date parsing function
function f_tcalParseDate(s_date) {

	var re_date = /^\s*(\d{1,2})\.(\d{1,2})\.(\d{2,4})\s*$/;
	if (!re_date.exec(s_date))
		return alert("Falsches Datum: '" + s_date
				+ "'.\nAkzeptiertes Format ist dd.mm.yyyy.")
	var n_day = Number(RegExp.$1), n_month = Number(RegExp.$2), n_year = Number(RegExp.$3);

	if (n_year < 100)
		n_year += (n_year < this.a_tpl.centyear ? 2000 : 1900);
	if (n_month < 1 || n_month > 12)
		return alert("Falscher Monat: '" + n_month + "'.\nErlaubt ist: 01-12.");
	var d_numdays = new Date(n_year, n_month, 0);
	if (n_day > d_numdays.getDate())
		return alert("Falscher Monatstag: '" + n_day + "'.\nErlaubt ist: 01 - "
				+ d_numdays.getDate() + ".");

	return new Date(n_year, n_month - 1, n_day);
}
// date generating function
function f_tcalGenerDate(d_date) {
	return ((d_date.getDate() < 10 ? '0' : '') + d_date.getDate() + "."
			+ (d_date.getMonth() < 9 ? '0' : '') + (d_date.getMonth() + 1)
			+ "." + d_date.getFullYear());
}

// implementation
function tcal(a_cfg, a_tpl) {
	// apply default template if not specified
	if (!a_tpl)
		a_tpl = A_TCALDEF;

	// register in global collections
	if (!window.A_TCALS)
		window.A_TCALS = [];
	if (!window.A_TCALSIDX)
		window.A_TCALSIDX = [];

	this.s_id = a_cfg.id ? a_cfg.id : A_TCALS.length;

	window.A_TCALS[this.s_id] = this;
	if(window.A_TCALSIDX)
		if(window.A_TCALSIDX.length)
			window.A_TCALSIDX[window.A_TCALSIDX.length] = this;

	// assign methods
	this.f_show = f_tcalShow;
	this.f_hide = f_tcalHide;
	this.f_toggle = f_tcalToggle;
	this.f_update = f_tcalUpdate;
	this.f_relDate = f_tcalRelDate;
	this.f_parseDate = f_tcalParseDate;
	this.f_generDate = f_tcalGenerDate;

	// create calendar icon
	this.s_iconId = 'tcalico_' + this.s_id;
	this.e_icon = f_getElement(this.s_iconId);
	if (!this.e_icon) {
		document.write('<img src="' + a_tpl.imgpath + 'cal.gif" id="'
				+ this.s_iconId + '" onclick="A_TCALS[\'' + this.s_id
				+ '\'].f_toggle()" class="tcalIcon" alt="Kalender öffnen" />');
		this.e_icon = f_getElement(this.s_iconId);
	}
	// save received parameters
	this.a_cfg = a_cfg;
	this.a_tpl = a_tpl;
}

function f_tcalShow(d_date) {

	// find input field
	if (!this.a_cfg.controlname)
		throw ("Feldname nicht angegeben");
	if (this.a_cfg.formname) {
		var e_form = document.forms[this.a_cfg.formname];
		if (!e_form)
			throw ("Form '" + this.a_cfg.formname + "' kann nicht gefunden werden");
		this.e_input = e_form.elements[this.a_cfg.controlname];
//		alert("if a_cfg.controlname " + this.a_cfg.controlname + " e_input " + this.e_input);
	} else {
		this.e_input = f_getElement(this.a_cfg.controlname);
	}

	if (!this.e_input || !this.e_input.tagName
			|| this.e_input.tagName != 'INPUT')
		throw ("Element '" + this.a_cfg.controlname
				+ "' existiert nicht in " + (this.a_cfg.formname ? "form '"
				+ this.a_cfg.formname + "'" : 'diesem Dokument'));

	// dynamically create HTML elements if needed
	this.e_div = f_getElement('tcal');
	if (!this.e_div) {
		this.e_div = document.createElement("DIV");
		this.e_div.id = 'tcal';
		document.body.appendChild(this.e_div);
	}
	this.e_shade = f_getElement('tcalShade');
	if (!this.e_shade) {
		this.e_shade = document.createElement("DIV");
		this.e_shade.id = 'tcalShade';
		document.body.appendChild(this.e_shade);
	}
	this.e_iframe = f_getElement('tcalIF')
	if (b_ieFix && !this.e_iframe) {
		this.e_iframe = document.createElement("IFRAME");
		this.e_iframe.style.filter = 'alpha(opacity=0)';
		this.e_iframe.id = 'tcalIF';
		this.e_iframe.src = this.a_tpl.imgpath + 'pixel.gif';
		document.body.appendChild(this.e_iframe);
	}

	// hide all calendars
	f_tcalHideAll();

	// generate HTML and show calendar
	this.e_icon = f_getElement(this.s_iconId);
	if (!this.f_update())
		return;

	this.e_div.style.visibility = 'visible';
	this.e_shade.style.visibility = 'visible';
	if (this.e_iframe)
		this.e_iframe.style.visibility = 'visible';

	// change icon and status
	this.e_icon.src = this.a_tpl.imgpath + 'no_cal.gif';
	this.e_icon.title = 'Kalender schliessen';
	this.b_visible = true;
}

function f_tcalHide(n_date) {
	if (n_date)
		this.e_input.value = this.f_generDate(new Date(n_date));

	// no action if not visible
	if (!this.b_visible)
		return;

	// hide elements
	if (this.e_iframe)
		this.e_iframe.style.visibility = 'hidden';
	if (this.e_shade)
		this.e_shade.style.visibility = 'hidden';
	this.e_div.style.visibility = 'hidden';

	// change icon and status
	this.e_icon = f_getElement(this.s_iconId);
	this.e_icon.src = this.a_tpl.imgpath + 'cal.gif';
	this.e_icon.title = 'Kalender öffnen';
	this.b_visible = false;
}

function f_tcalToggle() {
	return this.b_visible ? this.f_hide() : this.f_show();
}

function f_tcalUpdate(d_date) {

	var d_today = this.a_cfg.today ? this.f_parseDate(this.a_cfg.today)
			: f_tcalResetTime(new Date());
	var d_selected = this.e_input.value == '' ? (this.a_cfg.selected ? this
			.f_parseDate(this.a_cfg.selected) : d_today) : this
			.f_parseDate(this.e_input.value);

	// figure out date to display
	if (!d_date)
		// selected by default
		d_date = d_selected;
	else if (typeof (d_date) == 'number')
		// get from number
		d_date = f_tcalResetTime(new Date(d_date));
	else if (typeof (d_date) == 'string')
		// parse from string
		this.f_parseDate(d_date);

	if (!d_date)
		return false;

	// first date to display
	var d_firstday = new Date(d_date);
	d_firstday.setDate(1);
	d_firstday
			.setDate(1 - (7 + d_firstday.getDay() - this.a_tpl.weekstart) % 7);

	var a_class, s_html = '<table class="ctrl"><tbody><tr>'
			+ (this.a_tpl.yearscroll ? '<td' + this.f_relDate(d_date, -1, 'y')
					+ ' title="Vorheriges Jahr"><img src="'
					+ this.a_tpl.imgpath + 'prev_year.gif" /></td>' : '')
			+ '<td'
			+ this.f_relDate(d_date, -1)
			+ ' title="Vorheriger Monat"><img src="'
			+ this.a_tpl.imgpath
			+ 'prev_mon.gif" /></td><th>'
			+ this.a_tpl.months[d_date.getMonth()]
			+ ' '
			+ d_date.getFullYear()
			+ '</th><td'
			+ this.f_relDate(d_date, 1)
			+ ' title="Nächster Monat"><img src="'
			+ this.a_tpl.imgpath
			+ 'next_mon.gif" /></td>'
			+ (this.a_tpl.yearscroll ? '<td' + this.f_relDate(d_date, 1, 'y')
					+ ' title="Nächstes Jahr"><img src="' + this.a_tpl.imgpath
					+ 'next_year.gif" /></td></td>' : '')
			+ '</tr></tbody></table><table><tbody><tr class="wd">';

	// print weekdays titles
	for ( var i = 0; i < 7; i++)
		s_html += '<th>' + this.a_tpl.weekdays[(this.a_tpl.weekstart + i) % 7] + '</th>';
	s_html += '</tr>';

	// print calendar table
	var n_date, n_month, d_current = new Date(d_firstday);
	while (d_current.getMonth() == d_date.getMonth()
			|| d_current.getMonth() == d_firstday.getMonth()) {

		// print row heder
		s_html += '<tr>';
		for ( var n_wday = 0; n_wday < 7; n_wday++) {

			a_class = [];
			n_date = d_current.getDate();
			n_month = d_current.getMonth();

			// other month
			if (d_current.getMonth() != d_date.getMonth())
				a_class[a_class.length] = 'othermonth';
			// weekend
			if (d_current.getDay() == 0 || d_current.getDay() == 6)
				a_class[a_class.length] = 'weekend';
			// today
			if (d_current.valueOf() == d_today.valueOf())
				a_class[a_class.length] = 'today';
			// selected
			if (d_current.valueOf() == d_selected.valueOf())
				a_class[a_class.length] = 'selected';

			s_html += '<td onclick="A_TCALS[\''
					+ this.s_id
					+ '\'].f_hide('
					+ d_current.valueOf()
					+ ')"'
					+ (a_class.length ? ' class="' + a_class.join(' ') + '">'
							: '>') + n_date + '</td>'

			d_current.setDate(++n_date);
			while (d_current.getDate() != n_date
					&& d_current.getMonth() == n_month) {
				d_current.setHours(d_current.getHours + 1);
				d_current = f_tcalResetTime(d_current);
			}
		}
		// print row footer
		s_html += '</tr>';
	}
	s_html += '</tbody></table>';

	// update HTML, positions and sizes
	this.e_div.innerHTML = s_html;

	var n_width = this.e_div.offsetWidth;
	var n_height = this.e_div.offsetHeight;
	var n_top = f_getPosition(this.e_icon, 'Top') + this.e_icon.offsetHeight;
	var n_left = f_getPosition(this.e_icon, 'Left') - n_width
			+ this.e_icon.offsetWidth;
	if (n_left < 0)
		n_left = 0;

	this.e_div.style.left = n_left + 'px';
	this.e_div.style.top = n_top + 'px';

	this.e_shade.style.width = (n_width + 8) + 'px';
	this.e_shade.style.left = (n_left - 1) + 'px';
	this.e_shade.style.top = (n_top - 1) + 'px';
	this.e_shade.innerHTML = b_ieFix ? '<table><tbody><tr><td rowspan="2" colspan="2" width="6"><img src="'
			+ this.a_tpl.imgpath
			+ 'pixel.gif"></td><td width="7" height="7" style="filter:progid:DXImageTransform.Microsoft.AlphaImageLoader(src=\''
			+ this.a_tpl.imgpath
			+ 'shade_tr.png\', sizingMethod=\'scale\');"><img src="'
			+ this.a_tpl.imgpath
			+ 'pixel.gif"></td></tr><tr><td height="'
			+ (n_height - 7)
			+ '" style="filter:progid:DXImageTransform.Microsoft.AlphaImageLoader(src=\''
			+ this.a_tpl.imgpath
			+ 'shade_mr.png\', sizingMethod=\'scale\');"><img src="'
			+ this.a_tpl.imgpath
			+ 'pixel.gif"></td></tr><tr><td width="7" style="filter:progid:DXImageTransform.Microsoft.AlphaImageLoader(src=\''
			+ this.a_tpl.imgpath
			+ 'shade_bl.png\', sizingMethod=\'scale\');"><img src="'
			+ this.a_tpl.imgpath
			+ 'pixel.gif"></td><td style="filter:progid:DXImageTransform.Microsoft.AlphaImageLoader(src=\''
			+ this.a_tpl.imgpath
			+ 'shade_bm.png\', sizingMethod=\'scale\');" height="7" align="left"><img src="'
			+ this.a_tpl.imgpath
			+ 'pixel.gif"></td><td style="filter:progid:DXImageTransform.Microsoft.AlphaImageLoader(src=\''
			+ this.a_tpl.imgpath
			+ 'shade_br.png\', sizingMethod=\'scale\');"><img src="'
			+ this.a_tpl.imgpath + 'pixel.gif"></td></tr><tbody></table>'
			: '<table><tbody><tr><td rowspan="2" width="6"><img src="'
					+ this.a_tpl.imgpath
					+ 'pixel.gif"></td><td rowspan="2"><img src="'
					+ this.a_tpl.imgpath
					+ 'pixel.gif"></td><td width="7" height="7"><img src="'
					+ this.a_tpl.imgpath
					+ 'shade_tr.png"></td></tr><tr><td background="'
					+ this.a_tpl.imgpath + 'shade_mr.png" height="'
					+ (n_height - 7) + '"><img src="' + this.a_tpl.imgpath
					+ 'pixel.gif"></td></tr><tr><td><img src="'
					+ this.a_tpl.imgpath
					+ 'shade_bl.png"></td><td background="'
					+ this.a_tpl.imgpath
					+ 'shade_bm.png" height="7" align="left"><img src="'
					+ this.a_tpl.imgpath + 'pixel.gif"></td><td><img src="'
					+ this.a_tpl.imgpath
					+ 'shade_br.png"></td></tr><tbody></table>';

	if (this.e_iframe) {
		this.e_iframe.style.left = n_left + 'px';
		this.e_iframe.style.top = n_top + 'px';
		this.e_iframe.style.width = (n_width + 6) + 'px';
		this.e_iframe.style.height = (n_height + 6) + 'px';
	}
	return true;
}

function f_getPosition(e_elemRef, s_coord) {
	var n_pos = 0, n_offset, e_elem = e_elemRef;

	while (e_elem) {
		n_offset = e_elem["offset" + s_coord];
		n_pos += n_offset;
		e_elem = e_elem.offsetParent;
	}
	// margin correction in some browsers
	if (b_ieMac)
		n_pos += parseInt(document.body[s_coord.toLowerCase() + 'Margin']);
	else if (b_safari)
		n_pos -= n_offset;

	e_elem = e_elemRef;
	while (e_elem != document.body) {
		n_offset = e_elem["scroll" + s_coord];
		if (n_offset && e_elem.style.overflow == 'scroll')
			n_pos -= n_offset;
		e_elem = e_elem.parentNode;
	}
	return n_pos;
}

function f_tcalRelDate(d_date, d_diff, s_units_jn) {
	var s_units = (s_units_jn == 'y' ? 'FullYear' : 'Month');
	var d_result = new Date(d_date);
	d_result['set' + s_units](d_date['get' + s_units]() + d_diff);
	if (d_result.getDate() != d_date.getDate())
		d_result.setDate(0);
	return ' onclick="A_TCALS[\'' + this.s_id + '\'].f_update('
			+ d_result.valueOf() + ')"';
}

function f_tcalHideAll() {
	if(window.A_TCALSIDX)
		if(window.A_TCALSIDX.length)
			for ( var i = 0; i < window.A_TCALSIDX.length; i++)
				window.A_TCALSIDX[i].f_hide();
}

function f_tcalResetTime(d_date) {
	d_date.setHours(0);
	d_date.setMinutes(0);
	d_date.setSeconds(0);
	d_date.setMilliseconds(0);
	return d_date;
}

var f_getElement = document.all ? function(s_id) {
	return document.all[s_id]
} : function(s_id) {
	return document.getElementById(s_id)
};

if (document.addEventListener)
	window.addEventListener('scroll', f_tcalHideAll, false);
if (window.attachEvent)
	window.attachEvent('onscroll', f_tcalHideAll);

// global variables
var s_userAgent = navigator.userAgent.toLowerCase(), re_webkit = /WebKit\/(\d+)/i;
var b_mac = s_userAgent.indexOf('mac') != -1, b_ie5 = s_userAgent
		.indexOf('msie 5') != -1, b_ie6 = s_userAgent.indexOf('msie 6') != -1
		&& s_userAgent.indexOf('opera') == -1;
var b_ieFix = b_ie5 || b_ie6, b_ieMac = b_mac && b_ie5, b_safari = b_mac
		&& re_webkit.exec(s_userAgent) && Number(RegExp.$1) < 500;