var kalendar = function () {
	this.dny = function () {
		//hlavicka
		var objekt = this;

		this.datepicker.innerHTML = '';

		var header = document.createElement ('div');
		header.className = 'header';
		this.datepicker.appendChild (header);
		var title = document.createElement ('div');
		title.className = 'title';
		header.appendChild (title);
		var titleText = document.createElement ('span');
		titleText.className = 'titleText';
		titleText.style.cursor = 'pointer';
		titleText.innerHTML = this.nazvyMesicu[this.datum.getMonth()] + ' ' + this.datum.getFullYear();
		titleText.onclick = function () {
			objekt.mesice ();
		}
		title.appendChild (titleText);
		var previous = document.createElement ('div');
		previous.className = 'previous';
		previous.innerHTML = '«';
		previous.onclick = function () {
			objekt.datum.setMonth (objekt.datum.getMonth () - 1);
			objekt.dny ();
		}
		title.appendChild (previous);
		var next = document.createElement ('div');
		next.className = 'next';
		next.innerHTML = '»';
		next.onclick = function () {
			objekt.datum.setMonth (objekt.datum.getMonth () + 1);
			objekt.dny ();
		}
		title.appendChild (next);
		var closeButton = document.createElement ('div');
		closeButton.className = 'closeButton';
		closeButton.innerHTML = 'x';
		closeButton.onclick = function () {
			objekt.zavri ();
		}
		title.appendChild (closeButton);
		
		//telo
		var body = document.createElement ('div');
		body.className = 'body';
		this.datepicker.appendChild (body);
		var days = document.createElement ('div');
		days.className = 'days';
		body.appendChild (days);

		var titles = document.createElement ('div');
		titles.className = 'titles';
		days.appendChild (titles);

		for (var dny = 0; dny < 7; dny++) {
			var title = document.createElement ('div');
			title.className = 'title day day' + dny;
			title.innerHTML = this.nazvyDnu[dny].substr (0, 2);
			days.appendChild (title);
		}

		var zacatekMesice = new Date (this.datum.getFullYear (), this.datum.getMonth (), 1, 6);
		var denVTydnu = zacatekMesice.getDay ();
		
		var danyMesic = this.datum.getMonth ();

		var vybranyRok = this.vybraneDatum.getFullYear ();
		var vybranyMesic = this.vybraneDatum.getMonth ();
		var vybranyDen = this.vybraneDatum.getDate ();

		var aktualniRok = this.aktualniDatum.getFullYear ();
		var aktualniMesic = this.aktualniDatum.getMonth ();
		var aktualniDen = this.aktualniDatum.getDate ();

		var casVMilisekundach = zacatekMesice.getTime () - (denVTydnu * 86400000);
		if (denVTydnu == 0)
			casVMilisekundach -= 7 * 86400000;
		
		for (var tydny = 0; tydny < 6; tydny++) {
			var week = document.createElement ('div');
			week.className = 'week week' + tydny;
			days.appendChild (week);

			for (var dny = 0; dny < 7; dny++) {
				casVMilisekundach += 86400000;
				var noveDatum = new Date (casVMilisekundach);

				var jinyMesic = '';
				if (noveDatum.getMonth () != danyMesic)
					jinyMesic = ' otherMonth';

				var dnes = '';
				if (noveDatum.getFullYear () == aktualniRok && noveDatum.getMonth () == aktualniMesic && noveDatum.getDate () == aktualniDen)
					dnes = ' today';

				var vybrany = '';
				if (noveDatum.getFullYear () == vybranyRok && noveDatum.getMonth () == vybranyMesic && noveDatum.getDate () == vybranyDen)
					vybrany = ' selected';
				
				var day = document.createElement ('div');
				day.className = 'day day' + dny + jinyMesic + dnes + vybrany;
				day.innerHTML = noveDatum.getDate ();

				day.konecneDatum = noveDatum;
				day.onclick = function () {
					objekt.konecneDatum = this.konecneDatum;
					objekt.klikNaDen ();
				}

				week.appendChild (day);
			}
		}
	}	
	
	this.mesice = function () {
		//hlavicka
		var objekt = this;

		this.datepicker.innerHTML = '';

		var header = document.createElement ('div');
		header.className = 'header';
		this.datepicker.appendChild (header);
		var title = document.createElement ('div');
		title.className = 'title';
		header.appendChild (title);
		var titleText = document.createElement ('span');
		titleText.className = 'titleText';
		titleText.style.cursor = 'pointer';
		titleText.innerHTML = this.datum.getFullYear();
		titleText.onclick = function () {
			objekt.roky ();
		}
		title.appendChild (titleText);
		var previous = document.createElement ('div');
		previous.className = 'previous';
		previous.innerHTML = '&laquo;';
		previous.onclick = function () {
			objekt.datum.setFullYear (objekt.datum.getFullYear () - 1);
			objekt.mesice ();
		}
		title.appendChild (previous);
		var next = document.createElement ('div');
		next.className = 'next';
		next.innerHTML = '&raquo;';
		next.onclick = function () {
			objekt.datum.setFullYear (objekt.datum.getFullYear () + 1);
			objekt.mesice ();
		}
		title.appendChild (next);
		var closeButton = document.createElement ('div');
		closeButton.className = 'closeButton';
		closeButton.innerHTML = 'x';
		closeButton.onclick = function () {
			objekt.zavri ();
		}
		title.appendChild (closeButton);
		
		//telo
		var body = document.createElement ('div');
		body.className = 'body';
		this.datepicker.appendChild (body);
		var months = document.createElement ('div');
		months.className = 'months';
		body.appendChild (months);

		var vybranyRok = this.vybraneDatum.getFullYear ();
		var vybranyMesic = this.vybraneDatum.getMonth ();

		var aktualniRok = this.aktualniDatum.getFullYear ();
		var aktualniMesic = this.aktualniDatum.getMonth ();

		for (var mesice = 0; mesice < 12; mesice++) {
			var dnes = '';
			if (this.datum.getFullYear () == aktualniRok && mesice == aktualniMesic)
				dnes = ' today';

			var vybrany = '';
			if (this.datum.getFullYear () == vybranyRok && mesice == vybranyMesic)
				vybrany = ' selected';

			var month = document.createElement ('div');
			month.className = 'month month' + mesice + dnes + vybrany;
			month.innerHTML = this.nazvyMesicu[mesice].substr (0, 3);
			month.konecnyMesic = mesice;

			month.onclick = function () {
				objekt.datum.setMonth (this.konecnyMesic);
				objekt.dny ();
			}

			months.appendChild (month);
		}
	}
	
	this.roky = function () {
		//hlavicka
		var objekt = this;

		this.datepicker.innerHTML = '';

		var pocatecniRok = this.datum.getFullYear() - (this.datum.getFullYear() % 20);

		var header = document.createElement ('div');
		header.className = 'header';
		this.datepicker.appendChild (header);
		var title = document.createElement ('div');
		title.className = 'title';
		header.appendChild (title);
		var titleText = document.createElement ('span');
		titleText.className = 'titleText';
		titleText.style.cursor = 'pointer';
		titleText.innerHTML = pocatecniRok + '-' + (pocatecniRok + 19);
		title.appendChild (titleText);
		var previous = document.createElement ('div');
		previous.className = 'previous';
		previous.innerHTML = '&laquo;';
		previous.onclick = function () {
			objekt.datum.setFullYear (objekt.datum.getFullYear () - 20);
			objekt.roky ();
		}
		title.appendChild (previous);
		var next = document.createElement ('div');
		next.className = 'next';
		next.innerHTML = '&raquo;';
		next.onclick = function () {
			objekt.datum.setFullYear (objekt.datum.getFullYear () + 20);
			objekt.roky ();
		}
		title.appendChild (next);
		var closeButton = document.createElement ('div');
		closeButton.className = 'closeButton';
		closeButton.innerHTML = 'x';
		closeButton.onclick = function () {
			objekt.zavri ();
		}
		title.appendChild (closeButton);
		
		//telo
		var body = document.createElement ('div');
		body.className = 'body';
		this.datepicker.appendChild (body);
		var years = document.createElement ('div');
		years.className = 'years';
		body.appendChild (years);

		var vybranyRok = this.vybraneDatum.getFullYear ();

		var aktualniRok = this.aktualniDatum.getFullYear ();

		for (var roky = 0; roky < 20; roky++) {
			var dnes = '';
			if ((roky + pocatecniRok) == aktualniRok)
				dnes = ' today';

			var vybrany = '';
			if ((roky + pocatecniRok) == vybranyRok)
				vybrany = ' selected';

			var year = document.createElement ('div');
			year.className = 'year year' + roky + dnes + vybrany;
			year.innerHTML = roky + pocatecniRok;
			year.konecnyRok = roky + pocatecniRok;

			year.onclick = function () {
				objekt.datum.setFullYear (this.konecnyRok);
				objekt.mesice ();
			}

			years.appendChild (year);
		}
	}

	this.cas = function () {
		//hlavicka
		var objekt = this;

		this.datepicker.innerHTML = '';

		var header = document.createElement ('div');
		header.className = 'header';
		this.datepicker.appendChild (header);
		var title = document.createElement ('div');
		title.className = 'title';
		header.appendChild (title);
		var titleText = document.createElement ('span');
		titleText.className = 'titleText';
		titleText.style.cursor = 'pointer';
		titleText.innerHTML = this.konecneDatum.getDate () + ' ' + this.nazvyMesicu[this.konecneDatum.getMonth ()].substr (0, 3) + ', ' + this.konecneDatum.getFullYear ();
		title.appendChild (titleText);
		var closeButton = document.createElement ('div');
		closeButton.className = 'closeButton';
		closeButton.innerHTML = 'x';
		closeButton.onclick = function () {
			objekt.zavri ();
		}
		title.appendChild (closeButton);
		
		//telo
		var body = document.createElement ('div');
		body.className = 'body';
		this.datepicker.appendChild (body);
		var time = document.createElement ('div');
		time.className = 'time';
		body.appendChild (time);

		this.hour = document.createElement ('input');
		this.hour.className = 'hour';
		this.hour.type = 'text';
		this.hour.maxlength = 2;
		this.hour.value = doplnNulu (this.datum.getHours ());
		time.appendChild (this.hour);

		this.minutes = document.createElement ('input');
		this.minutes.className = 'minutes';
		this.minutes.type = 'text';
		this.minutes.maxlength = 2;
		this.minutes.value = doplnNulu (this.datum.getMinutes ());
		time.appendChild (this.minutes);

		var separator = document.createElement ('div');
		separator.className = 'separator';
		separator.innerHTML = ':';
		time.appendChild (separator);

		var ok = document.createElement ('input');
		ok.className = 'ok';
		ok.type = 'submit';
		ok.value = 'OK';
		ok.onclick = function () {
			objekt.konecneDatum.setHours (objekt.hour.value);
			objekt.konecneDatum.setMinutes (objekt.minutes.value);
			objekt.klikNaCas ();
		}
		
		time.appendChild (ok);
	}

	this.klikNaDen = function () {
		this.input.value = this.konecneDatum.getFullYear () + '-' + doplnNulu (this.konecneDatum.getMonth () + 1) + '-' + doplnNulu (this.konecneDatum.getDate ());
		if (this.nactiCas)
			this.cas ();
		else
			this.zavri ();
	}

	this.klikNaCas = function () {
		this.input.value = this.konecneDatum.getFullYear () + '-' + doplnNulu (this.konecneDatum.getMonth () + 1) + '-' + doplnNulu (this.konecneDatum.getDate ()) + ' ' + doplnNulu (this.konecneDatum.getHours ()) + ':' + doplnNulu (this.konecneDatum.getMinutes ());
		this.zavri ();
	}

	this.zavri = function () {
		document.body.removeChild (this.datepicker);
		this.zobrazeno = false;
	}

	this.zobraz = function (id, nactiCas) {
		this.nactiCas = nactiCas;

		if (this.zobrazeno)
			this.zavri ();
			
		this.zobrazeno = true;
		
		this.vybraneDatum = new Date ();
		this.aktualniDatum = new Date (); 
		this.datum = new Date ();

		var objekt = this;

		this.input = document.getElementById (id);

		this.datepicker = document.createElement ('div');
		this.datepicker.className = 'datepicker';
		var poziceInputu = getElementAbsolutePos (this.input);
		this.datepicker.style.left = poziceInputu.x + this.posunX + 'px';
		
		this.datepicker.style.top = poziceInputu.y + this.posunY + 'px';
		document.body.appendChild (this.datepicker);

		var zadanyDatum = this.input.value.split (/\D+/);
		zadanyDatum[0] *= 1;
		zadanyDatum[1] -= 1;
		zadanyDatum[2] *= 1;
		zadanyDatum[3] *= 1;
		zadanyDatum[4] *= 1;
		var testovaciDatum = new Date (zadanyDatum[0], zadanyDatum[1], zadanyDatum[2], zadanyDatum[3], zadanyDatum[4]);
		if (testovaciDatum.getFullYear () == zadanyDatum[0] && testovaciDatum.getMonth () == zadanyDatum[1] && testovaciDatum.getDate () == zadanyDatum[2] && testovaciDatum.getHours () == zadanyDatum[3] && testovaciDatum.getMinutes () == zadanyDatum[4]) {
			this.datum = new Date (zadanyDatum[0], zadanyDatum[1], zadanyDatum[2], zadanyDatum[3], zadanyDatum[4]);
			this.vybraneDatum = new Date (zadanyDatum[0], zadanyDatum[1], zadanyDatum[2], zadanyDatum[3], zadanyDatum[4]);		
		}
		else {
			var testovaciDatum = new Date (zadanyDatum[0], zadanyDatum[1], zadanyDatum[2]);
			if (testovaciDatum.getFullYear () == zadanyDatum[0] && testovaciDatum.getMonth () == zadanyDatum[1] && testovaciDatum.getDate () == zadanyDatum[2]) {
				this.datum = new Date (zadanyDatum[0], zadanyDatum[1], zadanyDatum[2], this.aktualniDatum.getHours (), this.aktualniDatum.getMinutes ());
				this.vybraneDatum = new Date (zadanyDatum[0], zadanyDatum[1], zadanyDatum[2], this.aktualniDatum.getHours (), this.aktualniDatum.getMinutes ());		
			}
		}

		this.dny ();
	}

	this.posunY = 3;
	this.posunX = 215;
	this.nazvyMesicu = new Array ('Leden', 'Únor', 'Březen', 'Duben', 'Květen', 'Červen', 'Červenec', 'Srpen', 'Září', 'Říjen', 'Listopad', 'Prosinec');
	this.nazvyDnu = new Array ('Pondělí', 'Úterý', 'Středa', 'Čtvrtek', 'Pátek', 'Sobota', 'Neděle');
	this.zobrazeno = false;
};