var aktSlide=0;
var aktBtn=0;

var slide_Interval=null;
var btn_Interval=null;
var activity_Interval=null;

var slides = new Array(4);
var btnl = new Array(2);
var btnh = new Array(2);

for (var i=0;i<4;i++)
{	slides[i] = new Image();
	slides[i].src = 'images/pre_' + i + '.gif';
}

for (var i=0;i<2;i++)
{	btnl[i] = new Image();
	btnh[i] = new Image();
	btnl[i].src = 'images/btn_' + i + 'h.gif';
	btnh[i].src = 'images/btn_' + i + '.gif';		
}


function SlideShow()
{	if (ie)
	{document.all['disc'].document['aktSlide'].src = slides[ ( aktSlide ) ].src; }
	else
	{document.layers['disc'].layers['bild'].document['aktSlide'].src = slides[ ( aktSlide ) ].src;}
	if ( aktSlide >= 3 ){ aktSlide = 0; }
	else { aktSlide++; }
}

function btn_On(reset, msec)
{	var btnname = 'btn' + aktBtn;
	if (ie)
	{document.all['disc'].document[btnname].src = btnh[ Math.floor (aktBtn/3) ].src;}
	else
	{document.layers['disc'].document[btnname].src = btnh[ Math.floor (aktBtn/3) ].src;}
	if (reset)
	{	setTimeout ( 'btn_Off(' + aktBtn + ')', msec);
		if ( aktBtn >= 5 ){ aktBtn = 0; }
		else { aktBtn++; }
	}
}

function btn_Off(btn)
{	var btnname = 'btn' + btn;
	if (ie)
	{document.all['disc'].document[btnname].src = btnl[ Math.floor (btn/3) ].src;}
	else
	{document.layers['disc'].document[btnname].src = btnl[ Math.floor (btn/3) ].src;}
}

function slide_setInterval( msec )
{	slide_Interval = setInterval ( 'SlideShow()' , msec);
}

function btn_setInterval( msec )
{	if ( runs_Interval( btn_Interval ) )	clearInterval ( btn_Interval );
	btn_Interval = setInterval ( 'btn_On(true,1000)', msec );
}

function btn_clearInterval ( )
{	if ( runs_Interval( btn_Interval ) )
	{	clearInterval( btn_Interval );
		btn_Interval=null;
	}
}

function activity_setInterval ( )
{	if ( runs_Interval( activity_Interval ) )	clearInterval ( activity_Interval );
	activity_Interval = setInterval ( 'btn_setInterval(1000);', 10000 );
}

function runs_Interval ( i )
{	if ( null == i ) return false;
	else return true;
}

function dHeight ( ) { return ( ( ie ) ? document.body.offsetHeight : document.height ); }
function dWidth ( ) { return ( ( ie ) ? document.body.offsetWidth : document.width ); }

function movePics ( disc_movetop, disc_moveleft )
{		btn0menu.style.top = btn0menu.offsetTop + disc_movetop;
		btn0menu.style.left = btn0menu.offsetLeft + disc_moveleft;
		btn1menu.style.top = btn1menu.offsetTop + disc_movetop;
		btn1menu.style.left = btn1menu.offsetLeft + disc_moveleft;
		btn2menu.style.top = btn2menu.offsetTop + disc_movetop;
		btn2menu.style.left = btn2menu.offsetLeft + disc_moveleft;
		btn3menu.style.top = btn3menu.offsetTop + disc_movetop;
		btn3menu.style.left = btn3menu.offsetLeft + disc_moveleft;
		btn4menu.style.top = btn4menu.offsetTop + disc_movetop;
		btn4menu.style.left = btn4menu.offsetLeft + disc_moveleft;
		btn5menu.style.top = btn5menu.offsetTop + disc_movetop;
		btn5menu.style.left = btn5menu.offsetLeft + disc_moveleft;
}

function centerDisc ( )
{	var disc_oldtop = 0;
	var disc_oldleft = 0;
	var disc_movetop = 0;
	var disc_moveleft = 0;
	if ( ie )
	{	disc_oldtop = document.all['disc'].offsetTop;
		disc_oldleft = document.all['disc'].offsetLeft;
		document.all['disc'].style.left = ( ( document.body.offsetWidth - document.all['disc'].offsetWidth ) / 2 );
		document.all['disc'].style.top = ( ( document.body.offsetHeight - document.all['disc'].offsetHeight ) / 2 );
		disc_movetop = ( ( document.body.offsetHeight - document.all['disc'].offsetHeight ) / 2 ) - disc_oldtop;
		disc_moveleft = ( ( document.body.offsetWidth - document.all['disc'].offsetWidth ) / 2 ) - disc_oldleft;
		movePics ( disc_movetop, disc_moveleft );
		document.all['disc'].style.visibility = ievisible;
		document.all['disc'].all['fenster'].style.visibility = ievisible;
		document.all['disc'].all['bild'].style.visibility = ievisible;
	}
	else
	{	document.layers['disc'].visibility = ievisible;
		document.layers['disc'].layers['fenster'].visibility = ievisible;
		document.layers['disc'].layers['bild'].visibility = ievisible;
	}
}

function UserAction(elem,action)
{	btn_clearInterval();
	clearInterval( activity_Interval );
	aktBtn = parseInt ( elem );
	if ( action )
	{	btn_On( false );
		if (ie)
		{	document.all['btn'+aktBtn+'menu'].style.visibility = ievisible;
			document.all['btn'+aktBtn+'menu'].all['btn'+aktBtn+'strich'].style.visibility = ievisible;
			document.all['btn'+aktBtn+'menu'].all['btn'+aktBtn+'tabelle'].style.visibility = ievisible;
		}
		else
		{	document.layers['btn'+aktBtn+'menu'].visibility = ievisible;
			document.layers['btn'+aktBtn+'menu'].layers['btn'+aktBtn+'strich'].visibility = ievisible;
			document.layers['btn'+aktBtn+'menu'].layers['btn'+aktBtn+'tabelle'].visibility = ievisible;
		}
	}
	else
	{	activity_setInterval();
		btn_Off(aktBtn);
		if (ie)
		{	document.all['btn'+aktBtn+'menu'].style.visibility = iehidden;
			document.all['btn'+aktBtn+'menu'].all['btn'+aktBtn+'strich'].style.visibility = iehidden;
			document.all['btn'+aktBtn+'menu'].all['btn'+aktBtn+'tabelle'].style.visibility = iehidden;
		}
		else
		{	document.layers['btn'+aktBtn+'menu'].visibility = iehidden;
			document.layers['btn'+aktBtn+'menu'].layers['btn'+aktBtn+'strich'].visibility = iehidden;
			document.layers['btn'+aktBtn+'menu'].layers['btn'+aktBtn+'tabelle'].visibility = iehidden;
		}
	}
}

function startScript()
{	centerDisc();
	slide_setInterval(3000);
	btn_setInterval(1000);
}