// JavaScript Document

var currentAreaCode = 0;

function getCurrentAreaCode() {
	return currentAreaCode;
}



(function(){
	
	setOnMouseEvents();
	
	function setOnMouseEvents() {
		var areas = ['area01','area02','area03','area04'];
		
		var i, area;
		for(i=0; i<areas.length; i++) {
			area = document.getElementById(areas[i]);
			area.areaCode = i+1;
			setRollOverImage(area);
			addEvent(area, 'mouseover', onMouseOverHandler);
			addEvent(area, 'mouseout', onMouseOutHandler);
		}
		
		function setRollOverImage(area) {
			var targetImage = area.getElementsByTagName('img')[0];
			targetImage.srcOut = targetImage.src;
			targetImage.srcOver = targetImage.src.replace(/\.([^\.]+)$/,'_active.$1');
			area.rolloverImage = targetImage;
		}
		
		function onMouseOverHandler() {
			this.rolloverImage.src = this.rolloverImage.srcOver;
			currentAreaCode = this.areaCode;			
		}
		
		function onMouseOutHandler() {
			this.rolloverImage.src = this.rolloverImage.srcOut;
			currentAreaCode = 0;
		}
	}

    function addEvent(eventTarget, eventName, func){
        if(eventTarget.addEventListener){
            // モダンブラウザ 
            eventTarget.addEventListener(eventName, func, false);
        }else if(window.attachEvent){
            // IE 
            eventTarget.attachEvent('on'+eventName, function(){func.apply(eventTarget);});
        }
    }

})();