ypSlideOutMenu.Registry = []
ypSlideOutMenu.aniLen = 400
ypSlideOutMenu.hideDelay = 1000
ypSlideOutMenu.minCPUResolution = 10

// constructor
function ypSlideOutMenu(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.dir         = dir
        this.orientation = dir == "left" || dir == "right" ? "h" : "v"
        this.dirType     = dir == "right" || dir == "down" ? "-" : "+"
        this.dim         = this.orientation == "h" ? width : height
        this.hideTimer     = false
        this.aniTimer     = false
        this.open         = false
        this.over         = false
        this.startTime     = 0

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

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

        var d = document

                var strCSS = '<style type="text/css">';
                strCSS += '#' + this.id + 'Container { visibility:hidden; '
        strCSS += 'left:' + left + 'px; '
        strCSS += 'top:' + top + 'px; '
        strCSS += 'overflow:hidden; z-index:10000; }'
        strCSS += '#' + this.id + 'Container, #' + this.id + 'Content { position:absolute; '
        strCSS += 'width:' + width + 'px; '
        strCSS += 'height:' + height + 'px; '
        strCSS += 'clip:rect(0 ' + width + ' ' + height + ' 0); '
        strCSS += '}'
                strCSS += '</style>';

                d.write(strCSS)

        this.load()
    }
}

ypSlideOutMenu.prototype.load = function() {
    var d = document
    var lyrId1 = this.id + "Container"
    var lyrId2 = this.id + "Content"
    var obj1 = this.dom ? d.getElementById(lyrId1) : this.ie ? d.all[lyrId1] : d.layers[lyrId1]
    if (obj1) var obj2 = this.ns4 ? obj1.layers[lyrId2] : this.ie ? d.all[lyrId2] : d.getElementById(lyrId2)
    var temp

    if (!obj1 || !obj2) window.setTimeout(this.gRef + ".load()", 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) / ypSlideOutMenu.aniLen / ypSlideOutMenu.aniLen 

        // set event handlers.
        if (this.ns4) this.menu.captureEvents(Event.MOUSEOVER | Event.MOUSEOUT);
        this.menu.onmouseover = new Function("ypSlideOutMenu.showMenu('" + this.id + "')")
        this.menu.onmouseout = new Function("ypSlideOutMenu.hideMenu('" + this.id + "')")

        //set initial state
        this.endSlide()
    }
}
    
ypSlideOutMenu.showMenu = function(id)
{
    var reg = ypSlideOutMenu.Registry
    var obj = ypSlideOutMenu.Registry[id]
    
    if (obj.container) {
        obj.over = true

        // close other menus.
        for (menu in reg) if (id != menu) ypSlideOutMenu.hide(menu)

        // 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)
    }
}

ypSlideOutMenu.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 = ypSlideOutMenu.Registry[id]
    if (obj.container) {
        if (obj.hideTimer) window.clearTimeout(obj.hideTimer)
        obj.hideTimer = window.setTimeout("ypSlideOutMenu.hide('" + id + "')", ypSlideOutMenu.hideDelay);
    }
}

ypSlideOutMenu.hide = function(id)
{
    var obj = ypSlideOutMenu.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)
}

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

ypSlideOutMenu.prototype.slide = function() {
    var elapsed = (new Date()).getTime() - this.startTime
    if (elapsed > ypSlideOutMenu.aniLen) this.endSlide()
    else {
        var d = Math.round(Math.pow(ypSlideOutMenu.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)
    }
}

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

ypSlideOutMenu.prototype.setVisibility = function(bShow) { 
    var s = this.ns4 ? this.container : this.container.style
    s.visibility = bShow ? "visible" : "hidden"
}
ypSlideOutMenu.prototype.moveTo = function(p) { 
    this.style[this.orientation == "h" ? "left" : "top"] = this.ns4 ? p : p + "px"
}
ypSlideOutMenu.prototype.getPos = function(c) {
    return parseInt(this.style[c])
}

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