var hTabs = new Array(5);
hTabs[0] = new Array(2);
hTabs[0][0] = "h_tab1";
hTabs[0][1] = "img/home/p_bg_hydro.jpg";
hTabs[1] = new Array(2);
hTabs[1][0] = "h_tab2";
hTabs[1][1] = "img/home/p_bg_biomass.jpg";
hTabs[2] = new Array(2);
hTabs[2][0] = "h_tab3";
hTabs[2][1] = "img/home/p_bg_power.jpg";
hTabs[3] = new Array(2);
hTabs[3][0] = "h_tab4";
hTabs[3][1] = "img/home/p_bg_hydro2.jpg";
hTabs[4] = new Array(2);
hTabs[4][0] = "h_tab5";
hTabs[4][1] = "img/home/p_bg_wind.jpg";

var selTab = "h_tab1";
var prevTab = "h_tab1";
var rotCount = 0;

var tabImgStart = 210;
var tabImgEnd = 0; 
var tabImgInt = 10;

function showTab(id) {
	var backImg = "";
	var optImg = "";
	prevTab = selTab;
	selTab = id;
	for ( var i=0; i<hTabs.length; i++) {
		document.getElementById(hTabs[i][0]).className = "div_h_tab_def";
		if ( hTabs[i][0] == prevTab ) backImg = hTabs[i][1];
	}
	
	document.getElementById("h_tabs").style.background = "url(" + backImg + ") no-repeat";
	document.getElementById(id).className = "div_h_tab_sel";

	tabImgStart = 210;
	tabImgEnd = 0; 
	moveTabImg();
}
function moveTabImg() {
	if(tabImgStart > tabImgEnd) tabImgStart = tabImgStart - tabImgInt;
	document.getElementById(selTab).style.top  = tabImgStart + 'px';
	if (tabImgStart > tabImgEnd ) {
		window.setTimeout('moveTabImg()',100);
	}
}
function rotTabs() {
	var tab = null;
	for ( var i=0; i<hTabs.length; i++ ) {
		if ( hTabs[i][0] == selTab ) {
			if ( i < hTabs.length-1 )
				tab = hTabs[i+1][0];
			else 
				tab = hTabs[0][0];
		}
	}
	if ( tab != null ) {
		showTab(tab);
		rotCount++;
	}
	if ( rotCount < 25 )
		setTimeout('rotTabs()', 7000);
}