var homeImageNum ;
var homeImageNo = 1 ;
var opacityBrowser = ( navigator.appVersion.toLowerCase().indexOf('msie') != -1 )? 1.5 : 1 ;
var Opacity = 1 ;
var OpacityTimer0 ;
var OpacityTimer1 ;
var OpacityTimer2 ;
var OpacityTimer3 ;
var homeImageElm ;
var homeImageArr = new Array() ;
var varmyAVL = navigator.appVersion.toLowerCase() ;


dom.event.addEventListener( window, 'load', initDocument ) ;

function initDocument(){
	if( document.getElementById('homeImageBox') ){

		homeImageElm = document.getElementById('homeImageBox').getElementsByTagName('img')[0] ;
		homeImageNum = ( homeImageElm.getAttribute('class') || homeImageElm.getAttribute('className') ) ;

		for( var i=0; i<homeImageNum; i++ ){
			var no = i+1 ;
			var homeImageName = 'images/root/index_top_image' + no + '.jpg' ;
				homeImageArr[no] = new Image() ;
				homeImageArr[no].src = homeImageName ;
		}
//		var homeImageTimer = setInterval('homeImageOpacity1()', 6000) ;
		OpacityTimer0 = setTimeout( 'homeImageOpacity1()' , 4000 ) ;

	}
}

function homeImageOpacity1(){
	Opacity = Opacity - 0.02/Opacity*opacityBrowser ;
	homeImageOpacitySet() ;
	if( Opacity >0.3 ){
		OpacityTimer1 = setTimeout( 'homeImageOpacity1()' , 25 ) ;
	}else{
		clearTimeout( OpacityTimer1 ) ;
		Opacity = 0.3 ;
		homeImageSelectNo() ;
	}
}

function homeImageOpacity2(){
	Opacity = Opacity + 0.01/Opacity*opacityBrowser ;
	homeImageOpacitySet() ;
	if( Opacity <1 ){
		OpacityTimer2 = setTimeout( 'homeImageOpacity2()' , 25 ) ;
	}else{
		clearTimeout( OpacityTimer2 ) ;
		Opacity = 1 ;
		clearTimeout( OpacityTimer3 ) ;
		OpacityTimer3 = setTimeout( 'homeImageOpacity1()' , 6000 ) ;
	}
}

function homeImageSelectNo(){
//	homeImageNo = Math.floor( Math.random()*homeImageNum+1 ) ;
	homeImageNo = ( homeImageNo<homeImageNum )? homeImageNo+1 : 1 ;
	homeImageElm.src = homeImageArr[homeImageNo].src ;
	if(homeImageElm.height>0)homeImageOpacity2() ;
}


function homeImageOpacitySet(){
	homeImageElm.style.opacity = Opacity ;
	homeImageElm.style.filter = 'alpha(opacity="' + Opacity*100 + '")' ;
}