var ie = ( navigator.appName.indexOf( "Explorer" ) != -1 );
var browserType = ( document.layers ) ? "ns" : ( ( document.getElementById ) ? "getEl" : "ie" ); 
var topLayers = new Array();
var leftLayers = new Array();
var rightLayers = new Array();
var topItems , leftItems , rightItems , topHigh , leftHigh , rightHigh;

function defineLayer( name ) {
	var layer;

	if( browserType == "getEl" ) {
		layer = eval( "document.getElementById( '"+name+"' ).style" );
		if ( ie ) {
			layer.cursor = "hand";
		} else  {
			layer.cursor = "pointer";
		}
	} else if ( browserType == "ie" ) {
		layer = eval( "document.all."+name+".style" );
		layer.cursor = "hand";
	} else {
		layer = eval( "document."+name );
		layer.cursor = "pointer";
	}
	return layer;
}

function getTopLayers() {
	for( i=0 ; i<topItems ; i++ ) {
		topLayers[i] = defineLayer( "topnavi"+i );
		topLayers[i+topItems] = defineLayer( "topnavihigh"+i );
	}
}

function getLeftLayers() {
	for( i=0 ; i<leftItems ; i++ ) {
		leftLayers[i] = defineLayer( "leftnavi"+i );
		leftLayers[i+leftItems] = defineLayer( "leftnavihigh"+i );
	}
}

function getRightLayers() {
	for( i=0 ; i<rightItems ; i++ ) {
		rightLayers[i] = defineLayer( "rightnavi"+i );
		rightLayers[i+rightItems] = defineLayer( "rightnavihigh"+i );
	}
}

function topNavi( element ) {
	for( i=topItems ; i<2*topItems ; i++ ) {
		if ( i - topItems != topHigh ) {
			topLayers[i].visibility = "hidden";
		}
	}
	if ( element < topItems ) {
		topLayers[element+topItems].visibility = "visible";
	}
}

function leftNavi( element ) {
	for( i=leftItems ; i<2*leftItems ; i++ ) {
		if ( i - leftItems != leftHigh ) {
			leftLayers[i].visibility = "hidden";
		}
	}
	if ( element < leftItems ) {
		leftLayers[element+leftItems].visibility = "visible";
	}
}

function rightNavi( element ) {
	for( i=rightItems ; i<2*rightItems ; i++ ) {
		if ( i - rightItems != rightHigh ) {
			rightLayers[i].visibility = "hidden";
		}
	}
	if ( element < rightItems ) {
		rightLayers[element+rightItems].visibility = "visible";
	}
}

function MouseOver( element , navi ) {
	if ( navi == "left" ) {
		leftNavi( element );
	} else if ( navi == "top" ) {
		topNavi( element );
	} else if ( navi == "right" ) {
		rightNavi( element );
	}
}

function MouseOut( navi ) {
	if ( navi == "left" ) {
		leftNavi( leftItems );
	} else if ( navi == "top" ) {
		topNavi( topItems );
	} else if ( navi == "right" ) {
		rightNavi( rightItems );
	}
}

function Navigate( where ) {
	window.location.href = where;
}

function NullEvent() {
}

function init( leftNaviItems , lHigh ) {
	initTop( 4 , 4 );
	initLeft( leftNaviItems , lHigh );
}

function initTop( naviItems , high ) {
	topItems = naviItems;
	topHigh = high;
	getTopLayers();
	topNavi( high );
}

function initLeft( naviItems , high ) {
	leftItems = naviItems;
	leftHigh = high;
	getLeftLayers();
	leftNavi( high );
}

function initRight( naviItems , high ) {
	rightItems = naviItems;
	rightHigh = high;
	getRightLayers();
	rightNavi( high );
}