function clear_city(m,f)
    {
        for (i = 1; i <7; i++) if (i!=m) 
        {
            cmd = "f.m"+i+".selectedIndex=0";
            eval(cmd);
        }
    }

    check_city = true
    function kontrola(f)
    {
        ok = 1;
        var cil = 0;
        var msg = '';
        if (check_city)
        {
			if ( document.getElementById ('odlet_do').value == cfg_select_city)
			ok = 0;
        }
        if (ok != 1) alert ('Zadejte prosím cílové město');
        check_city = true

		var dt_now  = new Date();
        var dt_min  = new Date();
		
        var dt_odlet = getMyDate("zadani_odlet_")
		var dt_navrat = getMyDate("zadani_prilet_");
		dt_now.setHours(0);
		dt_now.setMinutes(0);
		dt_now.setSeconds(0);
		dt_now.setMilliseconds(0);
		
		// Kontrola Stejen misto odletu a navratu
		m_odlet1=document.getElementById ('m_odlet1');
		if (one_way == 0  && ok == 1
			&& (   (m_odlet1.options[m_odlet1.selectedIndex].text == document.getElementById ('odlet_do').value)
			|| (document.getElementById ('odlet_z_text1').value == document.getElementById ('odlet_do').value) ) 
			) {
			alert('Cílová destinace nesmí být stejná jako místo odletu');
			ok = 0;
		} 
		
		var today = new Date();
		
		plus_days = 1;
		if ( today.getDay() == 5 && today.getHours() > 15 ) {
			plus_days = 3;
		}
		if ( today.getDay() == 6 || today.getHours() > 18 ) {
			plus_days = 2;
		}

		dt_min.setDate(dt_min.getDate() + plus_days);;

		// Minimalni datum odletu
		if ((dt_now.getTime() + plus_days*24*3600*1000) > dt_odlet.getTime() )
		{
			ok = 0;
			min_datum = dt_min.getDate() + '.' + (dt_min.getMonth() + 1) + '.' + dt_min.getFullYear();    
			alert ('Datum odletu nesmí být menší než '+ min_datum + '!');
		}

		// Odlet/Navrat
		if (one_way == 0)
		{
			
			if (dt_odlet > dt_navrat )
			{
				ok = 0;
				alert ('Datum odletu nesmí být větší než datum příletu!');
			}
			if (dt_navrat.getTime() > (dt_odlet.getTime()+365*24*3600*1000)  )
			{
				ok = 0;
				alert ('Nejdelší platnost kterékoliv letenky je jeden rok!');
			}
		}
		// Odlet +330
		var curdate = new Date();
		if (dt_odlet.getTime() > curdate.getTime()+330*24*3600*1000)
		{
			ok=0
			alert ('Datum odletu nesmí být více než 330 dní v budoucnosti!');
		}

		// Pocet cestujicich, pocet deti
		var pocet_cestujicich = parseInt(document.getElementById( 'pocet_cestujicich' ).value);
		var pocet_infantu     = parseInt(document.getElementById( 'pocet_infantu' ).value);
		if (pocet_cestujicich == 0) 
		{
			ok=0;
			alert ('Nebyl zadán počet cestujících.');
		}
		else {
			if (pocet_infantu*2 > pocet_cestujicich) 
			{
				ok=0;
				alert ('Jeden dospělý cestující může doprovázet pouze jedno dítě do věku 2 let');
			}
		}

		// Tolerance
		if (tolerance == 0 && ok == 1) 
		{
			dt_odlet_plus   = add_day(dt_odlet, document.getElementById ('zadani_odlet_plus').value);
			dt_odlet_minus  = add_day(dt_odlet, document.getElementById ('zadani_odlet_minus').value * -1);
			txt_odlet_plus   = dateToCZstring(dt_odlet_plus);
			txt_odlet_minus  = dateToCZstring(dt_odlet_minus);

			dt_navrat_plus  = add_day(dt_navrat, document.getElementById ('zadani_prilet_plus').value);
			dt_navrat_minus = add_day(dt_navrat, document.getElementById ('zadani_prilet_minus').value * -1);
			txt_navrat_plus  = dateToCZstring(dt_navrat_plus);
			txt_navrat_minus = dateToCZstring(dt_navrat_minus)
			
			txt_tolerance = 'Tolerance pro odlet '
			if (one_way == 0) txt_tolerance += 'a navrat '
			txt_tolerance += 'nebyla změněna. Platí tyto údaje? \n';
			txt_tolerance += 'Odlet:\t' + txt_odlet_minus + ' - ' + txt_odlet_plus + '\n';
			if (one_way == 0) { 
				txt_tolerance += 'Návrat:\t' + txt_navrat_minus + ' - ' + txt_navrat_plus + '\n';
			}
			ans = confirm(txt_tolerance);
			if (ans) tolerance = 1;
			else ok = 0;
		}

		// Odlet i navrat je ve stejny den
		if (   document.getElementById ('zadani_odlet_minus').value == 0 
			&& document.getElementById ('zadani_prilet_plus').value == 0
			&& dt_odlet.getDate() == dt_navrat.getDate() 
			&& dt_odlet.getMonth() == dt_navrat.getMonth() 
			&& dt_odlet.getYear() == dt_navrat.getYear() 
			&& one_way == 0 && ok == 1) {
			ans = confirm("Odlet i návrat je ve stejný den. Platí tyto údaje?");
			if (!ans) ok = 0;
		} 
			 
		
		if (f.vice_letist.checked && f.m_odlet2.value == "" && f.m_odlet3.value == "")
		{
			f.vice_letist.checked = false;
			setLetiste(f.vice_letist.checked);
		}
		

		if (ok == 1) return true;
		else return false;
    }
	
	function setLetiste(chckd)
	{
		//debugger;
		var disabled = !chckd;
		//var visibility = (disabled?'hidden':'visible')
		if (disabled)
		{	 
				
			 document.getElementById( 'div_odlet2' ).style.display = "none";
			 document.getElementById( 'div_odlet3' ).style.display = "none";
		}
		else 
		{
			document.getElementById( 'div_odlet2' ).style.display = "";
			document.getElementById( 'div_odlet3' ).style.display = "";
		}
		
	}

	function showNavrat(checked,both)
	{
		//debugger;
		var disabled = !checked;
		var display = (disabled?"none":"")
		//
		if (both) 
		{
			document.getElementById( 'td_navrat2' ).style.display = display;		
			document.getElementById( 'tr_navrat4' ).style.display = display;		
			document.getElementById( 'tr_navrat5' ).style.display = display;		
			if (!checked)
				document.getElementById( 'img_destinace' ).src = '../images/destinace.gif';
			else
				document.getElementById( 'img_destinace' ).src = '../images/navrat.gif';
		}
		else
		{
			if (checked) document.getElementById( 'img_destinace' ).src = '../images/destinace.gif';
			else document.getElementById( 'img_destinace' ).src = '../images/navrat.gif';
		}
		
		document.getElementById( 'td_navrat3' ).style.display = display;		

		if (!document.getElementById( 'open_jaw' ).checked )
			document.getElementById( 'td_navrat3' ).style.display = "none";		
		
		document.getElementById( 'navrat_z' ).value = cfg_select_city;		

	}
	
	function odletChange(field,num)
	{
		//alert(field.caption);
		
		if (field.value == "@@@")
		{
			var select = "div_select_odlet" + num;
			var text = "div_text_odlet"  + num;
			
			document.getElementById(  select ).style.display = "none";
			document.getElementById( text ).style.display = "";		
		}
	}
	
	function OdletDtChange()
	{
		var dt_odlet = getMyDate("zadani_odlet_")
		var dt_navrat = getMyDate("zadani_prilet_");
		setMyDate("zadani_odlet_",dt_odlet);
		
		if (dt_odlet.getTime() > dt_navrat.getTime())
		{
			dt_navrat.setTime(dt_odlet.getTime()+(7*24*3600*1000)); 
			setMyDate("zadani_prilet_",dt_navrat);
		}
		d=document.getElementById("odlet_dt_day");
		d.innerHTML = getCzDayOfWeek(dt_odlet.getDay());
		NavratDtChange();
	}

	function NavratDtChange()
	{
		//alert(" NavratDtChange");
		var dt_navrat = getMyDate("zadani_prilet_");
		setMyDate("zadani_prilet_",dt_navrat);
		//alert(" After setMyDate");
		d = document.getElementById("navrat_dt_day");
		d.innerHTML = getCzDayOfWeek(dt_navrat.getDay());
	}
	
	var selected_field = null;
	var dialogWindow = null;
	var DivName = null; 
	
	function ShowVyber(field,Div)
	{
		var url = 'vyber.php';
		var width = 1000;
		var height = 750;
		var left = 0;

		DivName = Div;
		selected_field = document.getElementById(field);
		
		
		dialogWindow=window.open(url,"Vyber","dependent=yes, menubar=no, location=no, resizable=yes, width=" + width + ", height=" + height + ", toolbar=no, scrollbars=yes, left=" + left + ", top=0" );
		
	}
	
	function SetCity(City)
	{
		
		if (DivName != '')
		{
			document.getElementById('div_text_' + DivName).style.display = "";
			document.getElementById('div_select_' + DivName).style.display = "none";
		}
		selected_field.value = City;
	}
	
	function ChangedVyber(fieldname,divname,val)
	{
		if (val == "@@@") ShowVyber(fieldname,divname);
	}
	
	function getMyDate(field_name)
	{
		day = parseInt(document.getElementById(field_name+'_1').value);
		dtshort = document.getElementById(field_name+'_short').value;

		re = /^(\d+)\D(\d+)$/
		arr = re.exec(dtshort)

		month = parseInt(arr[1]);
		mm = month-1;
		year=parseInt(arr[2])
		
		//alert (year + ' ' + mm + ' ' + day)
		myday = new Date(year, mm, day);
		return myday;
	}

	function setMyDate(field_name,myDate)
	{
		day = myDate.getDate();
		//alert (myDate);
		document.getElementById(field_name+'_1').value = day;
		month = parseInt(myDate.getMonth()) + 1;
		short = month+"/"+myDate.getFullYear();
		document.getElementById(field_name+'_short').value = short;
	}