SlideMenu.Registry = []
SlideMenu.aniLen = 300
SlideMenu.hideDelay = 250
SlideMenu.minCPUResolution = 8

// constructor
function SlideMenu(id, dir, left, top, width, height) {
	this.ie  = document.all ? 1 : 0
	this.ns4 = document.layers ? 1 : 0
	this.dom = document.getElementById ? 1 : 0

	if (this.ie || this.ns4 || this.dom) {
		this.id		 = id
		this.dirType	 = dir == "dw" ? "-" : "+"
		this.dim		 = height
		this.hideTimer	 = false
		this.aniTimer	 = false
		this.open		 = false
		this.over		 = false
		this.startTime	 = 0

		// global reference to this object
		this.gRef = "SlideMenu_"+id
		eval(this.gRef+"=this")

		// add this menu object to an internal list of all menus
		SlideMenu.Registry[id] = this

		var d = document
		d.write('<style type="text/css">')
		d.write('#' + this.id + 'Container { visibility:hidden; ')
		d.write('left:' + left + 'px; ')
		d.write('top:' + top + 'px; ')
		d.write('overflow:hidden; }')
		d.write('#' + this.id + 'Container, #' + this.id + 'Content { position:absolute; ')
		d.write('width:' + width + 'px; ')
		d.write('height:' + height + 'px; ')
		d.write('clip:rect(0 ' + width + ' ' + height + ' 0); ')
		d.write('}')
		d.write('</style>')

		this.init()
	}
}
SlideMenu.prototype.init = function() {

	var d = document
	var lyrId1 = this.id + "Container"
	var lyrId2 = this.id + "Content"
	
	if(this.dom) {
		var obj1 = d.getElementById(lyrId1)
	} else if(this.ie) {
		var obj1 = d.all[lyrId1]
	} else {
		var obj1 = d.layers[lyrId1]
	}
	if (obj1) {
		if(this.ns4) {
			var obj2 =obj1.layers[lyrId2] 
		} else if(this.ie) {
			var obj2 =	d.all[lyrId2]
		} else {
			var obj2 =	d.getElementById(lyrId2)
		}
	}
	var temp

	if (!obj1 || !obj2) {
		window.setTimeout(this.gRef + ".init()", 100)
	} else {
		this.container	= obj1
		this.menu		= obj2
		this.style		= this.ns4 ? this.menu : this.menu.style
		this.homePos	= eval("0" + this.dirType + this.dim)
		this.outPos		= 0
		this.accelConst	= (this.outPos - this.homePos) / SlideMenu.aniLen / SlideMenu.aniLen 

		// set event handlers.
		if (this.ns4) {
			this.menu.captureEvents(Event.MOUSEOVER | Event.MOUSEOUT);
		}
		this.menu.onmouseover = new Function("SlideMenu.showMenu('" + this.id + "')")
		this.menu.onmouseout = new Function("SlideMenu.hideMenu('" + this.id + "')")
		//set initial state
		this.endSlide()
	}
}
	
SlideMenu.showMenu = function(id) {
	var reg = SlideMenu.Registry
	var obj = SlideMenu.Registry[id]
	
	if (obj.container) {
		obj.over = true
		// close other menus.
		// if this menu is scheduled to close, cancel it.
		if (obj.hideTimer) { 
			reg[id].hideTimer = window.clearTimeout(reg[id].hideTimer)
		}
		// if this menu is closed, open it.
		if (!obj.open && !obj.aniTimer) {
		
			reg[id].startSlide(true)
		}
	}
}

SlideMenu.hideMenu = function(id) {
	// schedules the menu to close after <hideDelay> ms, which
	// gives the user time to cancel the action if they accidentally moused out
	var obj = SlideMenu.Registry[id]
	if (obj.container) {
		if (obj.hideTimer) {
			window.clearTimeout(obj.hideTimer)
		}
		obj.hideTimer = window.setTimeout("SlideMenu.hide('" + id + "')", SlideMenu.hideDelay);
	}
}

SlideMenu.hide = function(id) {
	var obj = SlideMenu.Registry[id]
	obj.over = false

	if (obj.hideTimer) {
		window.clearTimeout(obj.hideTimer)
	}
	
	// flag that this scheduled event has occured.
	obj.hideTimer = 0

	// if this menu is open, close it.
	if (obj.open && !obj.aniTimer) {
		obj.startSlide(false)
	}
}

SlideMenu.prototype.startSlide = function(open) {
//	this[open ? "onactivate" : "ondeactivate"]()
	if(open) {
		this["onactivate"]()
	} else {
		this[ "ondeactivate"]()
	}
	this.open = open
	if (open) {
		this.setVisibility(true)
	}
	this.startTime = (new Date()).getTime()	
	this.aniTimer = window.setInterval(this.gRef + ".slide()", SlideMenu.minCPUResolution)
}

SlideMenu.prototype.slide = function() {
	var elapsed = (new Date()).getTime() - this.startTime
	if (elapsed > SlideMenu.aniLen) {
		this.endSlide()
	} else {
		var d = Math.round(Math.pow(SlideMenu.aniLen-elapsed, 2) * this.accelConst)
		if (this.open && this.dirType == "-")		d = -d
		else if (this.open && this.dirType == "+")	d = -d
		else if (!this.open && this.dirType == "-")	d = -this.dim + d
		else								d = this.dim + d
		this.moveTo(d)
	}
}

SlideMenu.prototype.endSlide = function() {
	this.aniTimer = window.clearTimeout(this.aniTimer)
	if(this.open) {
		this.moveTo(this.outPos)	
	} else {
		this.moveTo(this.homePos)		
	}
	if (!this.open) {
		this.setVisibility(false)
	}
	if ((this.open && !this.over) || (!this.open && this.over)) {
		this.startSlide(this.over)
	}
}

SlideMenu.prototype.setVisibility = function(bShow) { 
	if(this.ns4) {
		var s = this.container
	} else {
	 	var s = this.container.style
	}
	if(bShow) {
		s.visibility = "visible"
	} else {
		s.visibility ="hidden"
	}
}
SlideMenu.prototype.moveTo = function(p) { 
	if(this.ns4) {
		this.style["top"] = p
	} else {
		this.style["top"] = p + "px"	
	}
}
SlideMenu.prototype.getPos = function(c) {
	return parseInt(this.style[c])
}

// events
SlideMenu.prototype.onactivate		= function() { }
SlideMenu.prototype.ondeactivate	= function() { }