//var poc_obr = 1
var sviti = 0
var ooo

function dej_cookie(kukina){
	var pom = document.cookie+';'
	kukina+='='
	
	if (pom==';') return 0
	
	var offset = pom.indexOf(kukina)
	if(offset == -1) return 0
	offset += kukina.length

	return unescape(document.cookie.substring(offset, pom.indexOf(";", offset)))
}

function poloha(){
	if (!ooo) return false

	var horni_kraj=parseInt((parseInt(document.body.clientHeight)
				  			-parseInt(ooo.style.height))/2)

	ooo.style.top = horni_kraj < 0
					?document.body.scrollTop+5//maly monitor,dej odshora
					:document.body.scrollTop+horni_kraj+'px'

	ooo.style.backgroundColor=ooo.offsetTop < 110?'green':'#1d2099';
}

function velky_obr(n){
	ooo=document.getElementById('velky_obr')
	if (n < 0) 	{
		ooo.style.display='none'
		return false
	}
	sviti = n

	velky = document.f
		 &&	document.f.px900 
		 && document.f.px900.checked 
		 && px900[n]
		 ||
		   !document.f
		 && px900[n]  
		 && dej_cookie('px900')
		 
//		 && document.f['px900'+n] 
//		 && document.f['px900'+n].value > 0
	
	px=velky?'900':'600'

	ooo.style.width	=velky?'950':'650'
	ooo.style.height=velky?'730':'530'
	
	if (document.getElementById('sipkaL')) {
		document.getElementById('sipkaL').width=
		document.getElementById('sipkaP').width=velky?'450':'300'

		document.getElementById('sipkaL').height=
		document.getElementById('sipkaP').height=velky?'600':'400'
	}

	//if (!document.getElementById('o'+n)) alert(n)
	//document.getElementById('div_obr_popis').innerHTML=document.getElementById('o'+n).parentNode.title
	document.getElementById('div_obr_popis').innerHTML=document.getElementById('popis'+n).innerHTML
	document.getElementById('div_obr_popis').style.top=(parseInt(ooo.style.height)-100)+'px'
	
	if (document.getElementById('div_obr_nazor')
	 && document.getElementById('nazor'+n))
	document.getElementById('div_obr_nazor').innerHTML=document.getElementById('nazor'+n).innerHTML
	
	var src=document.getElementById('o'+n).src
		src=src.substring(0,src.length-4)+'-'+px+src.substring(src.length-4)
	ooo.style.backgroundImage=	'url(\"'+ src +'\")'
	
	if (ooo.style.display!='block')
		ooo.style.display='block'

	poloha()

	if(zdroj)	
	document.getElementById('div_obr_zdroj').innerHTML=zdroj[n]
	document.getElementById('div_obr_url').innerHTML=src
	return false
}


function obr(){//pri on_scroll
	ooo=document.getElementById('velky_obr')
	//document.getElementById('velky_obr').style.top=document.body.scrollTop+190
	poloha()
}

function dalsi(n){
	velky_obr((sviti + n + poc_obr) % poc_obr)
	poloha()
	return false;		
}

function zmen_popisky(x){
	var displ=x?'block':'none'
	var i=0
	
	while (document.getElementById('popis'+i)) {
		document.getElementById('popis'+i).style.display=displ
		if (document.getElementById('nazor'+i))
		document.getElementById('nazor'+i).style.display=displ
		document.getElementById('clear'+i).style.display=displ
		i++
	}
	
	document.cookie='popisky='+(x?1:0)+'; path=/;'
}
function zmen_900(x){
	document.cookie='px900='+(x?1:0)+'; path=/;'
	if (document.getElementById('velky_obr').style.display=='block') velky_obr(sviti)
}