function Browser() {
	var ua, s, i;
	this.isIE    = false;
	this.isNS    = false;
	this.version = null;

	ua = navigator.userAgent;
	// IE
	s = "MSIE";
	if ((i = ua.indexOf(s)) >= 0) {
		this.isIE = true;
		this.version = parseFloat(ua.substr(i + s.length));
		return;
	}

	// NN6
	s = "Netscape6/";
	if ((i = ua.indexOf(s)) >= 0) {
		this.isNS = true;
		this.version = parseFloat(ua.substr(i + s.length));
		return;
	}

	// Safari
	s = "Safari";
	if ((i = ua.indexOf(s)) >= 0) {
		this.isSA = true;
		this.version = 1.0;
		return;
	}

	// Gecko
	s = "Gecko";
	if ((i = ua.indexOf(s)) >= 0) {
		this.isNS = true;
		this.version = 6.1;
		return;
	}
}

var browser = new Browser();
var activeButton = null;

if (browser.isIE) {
	document.onmousedown = pageMousedown;
} else {
	document.addEventListener("mousedown", pageMousedown, true);
}

// pageMousedown
function pageMousedown(event) {
	var el;
	
	if (activeButton == null) {
		return;
	}
	if (browser.isIE) {
		el = window.event.srcElement;
	} else {
		el = (event.target.tagName ? event.target : event.target.parentNode);
	}

	if (el == activeButton) {
		return;
	}

	if (getContainerWith(el, "DIV", "submenubox") == null) {
		resetButton(activeButton);
		activeButton = null;
	}
}

// buttonClick
function buttonClick(event, menuId) {
	var button;

	if (browser.isIE) {
		button = window.event.srcElement;
	} else {
		button = event.currentTarget;
	}

	button.blur();

	if (button.menu == null) {
		button.menu = document.getElementById(menuId);
		if (button.menu.isInitialized == null) {
			menuInit(button.menu);
		}
	}
	
	if (activeButton != null) {
		resetButton(activeButton);
	}
	
	if (button != activeButton) {
		depressButton(button);
		activeButton = button;
	} else {
	//	activeButton = null;
// 再度Overしても消えない/
		depressButton(button);
		activeButton = button;
	}
	return false;
}

// buttonMouseover
function buttonMouseover(event, menuId) {
	var button;
	if (browser.isIE) {
		button = window.event.srcElement;
	} else {
		button = event.currentTarget;
	}

	if (activeButton != null && activeButton != button) {
		buttonClick(event, menuId);
	}
}

// depressButton
function depressButton(button) {
	var x, y;

	x = getPageOffsetLeft(button);
	y = getPageOffsetTop(button) + button.offsetHeight;

	button.menu.style.left = x + "px";
	button.menu.style.top  = y + "px";
	button.menu.style.visibility = "visible";
}

// resetButton
function resetButton(button) {
	if (button.menu != null) {
		closeSubMenu(button.menu);
		button.menu.style.visibility = "hidden";
	}
}

// resetButtonPage(ページ用)
function resetButtonPage(activeButton) {
	if (activeButton != null) {
		resetButton(activeButton);
		activeButton = null;
	}
}

// menuMouseover
function menuMouseover(event) {
	var menu;

	if (browser.isIE) {
		menu = getContainerWith(window.event.srcElement, "DIV", "submenubox");
	} else {
		menu = event.currentTarget;
	}

	if (menu.activeItem != null) {
		closeSubMenu(menu);
	}
}

// menuItemMouseover
function menuItemMouseover(event, menuId) {
	var item, menu, x, y;
	
	if (browser.isIE) {
		item = getContainerWith(window.event.srcElement, "A", "submenu");
	} else {
		item = event.currentTarget;
		menu = getContainerWith(item, "DIV", "submenubox");
	}

	if (menu.activeItem != null) {
		closeSubMenu(menu);
		menu.activeItem = item;
	}

	if (item.subMenu == null) {
		item.subMenu = document.getElementById(menuId);
		if (item.subMenu.isInitialized == null) {
			menuInit(item.subMenu);
		}
	}

	x = getPageOffsetLeft(item) + item.offsetWidth+1.5;
	y = getPageOffsetTop(item)-1;

	var maxX, maxY;

	if (browser.isNS) {
		maxX = window.scrollX + window.innerWidth;
		maxY = window.scrollY + window.innerHeight;
	}
	
	if (browser.isIE) {
		maxX = (document.documentElement.scrollLeft   != 0 ? document.documentElement.scrollLeft   : document.body.scrollLeft)
				+ (document.documentElement.clientWidth  != 0 ? document.documentElement.clientWidth  : document.body.clientWidth);
		maxY = (document.documentElement.scrollTop    != 0 ? document.documentElement.scrollTop    : document.body.scrollTop)
				+ (document.documentElement.clientHeight != 0 ? document.documentElement.clientHeight : document.body.clientHeight);
	}
	
	if (browser.isSA) {
		maxX = window.scrollX + window.innerWidth;
		maxY = window.scrollY + window.innerHeight;
	}

	maxX -= item.subMenu.offsetWidth;
	maxY -= item.subMenu.offsetHeight;

	if (x > maxX) {
		x = Math.max(0, x - item.offsetWidth - item.subMenu.offsetWidth
				+ (menu.offsetWidth - item.offsetWidth));
		y = Math.max(0, Math.min(y, maxY));
	}

	if (browser.isSA) {
		item.subMenu.style.left = (x-9) + "px";
		item.subMenu.style.top  = (y-36) + "px";
	} else {
		item.subMenu.style.left = x + "px";
		item.subMenu.style.top  = y + "px";
	}
	item.subMenu.style.visibility = "visible";

	if (browser.isIE) {
		window.event.cancelBubble = true;
	} else {
		event.stopPropagation();
	}
}

// closeSubMenu
function closeSubMenu(menu) {
	if (menu == null || menu.activeItem == null) {
		return;
	}

	if (menu.activeItem.subMenu != null) {
		closeSubMenu(menu.activeItem.subMenu);
		menu.activeItem.subMenu.style.visibility = "hidden";
		menu.activeItem.subMenu = null;
	}
	menu.activeItem = null;
}

// menuInit
function menuInit(menu) {
	var itemList, spanList;
	var textEl, arrowEl;
	var itemWidth;
	var w, dw;
	var i, j;

	if (browser.isIE) {
		menu.style.lineHeight = "2.5ex";
		spanList = menu.getElementsByTagName("SPAN");
		for (i = 0; i < spanList.length; i++) {
			if (hasClassName(spanList[i], "MENUITEMARROW")) {
				spanList[i].style.fontFamily = "Webdings";
				spanList[i].firstChild.nodeValue = "4";
			}
		}
	}

	itemList = menu.getElementsByTagName("A");
	if (itemList.length > 0) {
		itemWidth = itemList[0].offsetWidth;
	} else {
		return;
	}

	for (i = 0; i < itemList.length; i++) {
		spanList = itemList[i].getElementsByTagName("SPAN");
		textEl  = null;
		arrowEl = null;
		for (j = 0; j < spanList.length; j++) {
			if (hasClassName(spanList[j], "MENUITEMTEXT")) {
				textEl = spanList[j];
			}
			if (hasClassName(spanList[j], "MENUITEMARROW")) {
				arrowEl = spanList[j];
			}
		}
		if (textEl != null && arrowEl != null) {
			textEl.style.paddingRight = (itemWidth - (textEl.offsetWidth + arrowEl.offsetWidth)) + "px";
		}
	}

	if (browser.isIE) {
		w = itemList[0].offsetWidth;
		itemList[0].style.width = w + "px";
		dw = itemList[0].offsetWidth - w;
		w -= dw;
		itemList[0].style.width = w + "px";
	}
	menu.isInitialized = true;
}

// getContainerWith
function getContainerWith(node, tagName, className) {
	while (node != null) {
		if (node.tagName != null && node.tagName == tagName && hasClassName(node, className)) {
			return node;
		}
		node = node.parentNode;
	}
	return node;
}

// hasClassName
function hasClassName(el, name) {
	var i, list;

	list = el.className.split(" ");
	for (i = 0; i < list.length; i++) {
		if (list[i] == name) {
			return true;
		}
	}
	return false;
}

// removeClassName
function removeClassName(el, name) {
	var i, curList, newList;

	if (el.className == null) {
		return;
	}

	newList = new Array();
	curList = el.className.split(" ");
	for (i = 0; i < curList.length; i++) {
		if (curList[i] != name) {
			newList.push(curList[i]);
		}
	}
	el.className = newList.join(" ");
}

// サブメニューのX座標位置
function getPageOffsetLeft(el) {
	var x;
	x = el.offsetLeft;
/*	if (el.offsetParent != null) {
		x += getPageOffsetLeft(el.offsetParent);
	}*/
  return x;
}

// サブメニューのY座標位置
function getPageOffsetTop(el) {
	var y;
	 y = el.offsetTop;
	if (el.offsetParent != null)
//		y += getPageOffsetTop(el.offsetParent)+0.8;
		y += getPageOffsetTop(el.offsetParent);
	return y;
}