// Original:  Eddie Traversa (psych3@primus.com.au) -->
// Web Site:  http://dhtmlnirvana.com/ -->

// This script and many more are available free online at -->
// The JavaScript Source!! http://javascript.internet.com -->

window.onerror = null;
var topMargin = 0; //position div top
var slideTime = 1200;
var ns6 = (!document.all && document.getElementById);
var ie4 = (document.all);
var ns4 = (document.layers);

function layerObject(id,left) {
    if (ns6) {
        this.obj = document.getElementById(id).style;
        this.obj.left = left;
        return this.obj;
    }
    else if(ie4) {
        this.obj = document.all[id].style;
        this.obj.left = left;
        return this.obj;
    }
    else if(ns4) {
        this.obj = document.layers[id];
        this.obj.left = left;
        return this.obj;
    }
}

function layerSetup() {
    //floatLyr = new layerObject('box', pageWidth * .5);
    //floatLyr = new layerObject('box', 760);
    floatLyr = new layerObject('shopnavigation', 5); //position div left
    window.setInterval("main()", 10)
}

function floatObject() {
    if (ns4 || ns6) {
        findHt = window.innerHeight;
    } else if(ie4) {
        findHt = document.body.clientHeight;
    }
} 


function main() {
    if (ns4) {
        this.currentY = document.layers["shopnavigation"].top;
        this.scrollTop = window.pageYOffset;
        mainTrigger();
    }
    else if(ns6) {
        this.currentY = parseInt(document.getElementById('shopnavigation').style.top);
        this.scrollTop = window.pageYOffset;
        mainTrigger();
    } else if(ie4) {
        this.currentY = shopnavigation.style.pixelTop;
        this.scrollTop = document.body.scrollTop;
        mainTrigger();
    }
}
function mainTrigger() {
    var newTargetY = this.scrollTop + this.topMargin;
    if ( this.currentY != newTargetY ) {
        if ( newTargetY != this.targetY ) {
            this.targetY = newTargetY;
            floatStart();
        }
        animator();
    }
}

function floatStart() {
    var now = new Date();
    this.A = this.targetY - this.currentY;
    this.B = Math.PI / ( 2 * this.slideTime );
    this.C = now.getTime();
    if (Math.abs(this.A) > this.findHt) {
        this.D = this.A > 0 ? this.targetY - this.findHt : this.targetY + this.findHt;
        this.A = this.A > 0 ? this.findHt : -this.findHt;
    }
    else {
        this.D = this.currentY;
    }
}

function animator() {
    var now = new Date();
    var newY = this.A * Math.sin( this.B * ( now.getTime() - this.C ) ) + this.D;
    newY = Math.round(newY);
    if (( this.A > 0 && newY > this.currentY ) || ( this.A < 0 && newY < this.currentY )) {
        if ( ie4 ) document.all.shopnavigation.style.pixelTop = newY;
        if ( ns4 ) document.layers["shopnavigation"].top = newY;
        if ( ns6 ) document.getElementById("shopnavigation").style.top = newY + "px";
    }
}

function startfloating() {
    if(ns6||ns4) {
        pageWidth = innerWidth;
        pageHeight = innerHeight;
        layerSetup();
        floatObject();
    }
    else if(ie4) {
        pageWidth = document.body.clientWidth;
        pageHeight = document.body.clientHeight;
        layerSetup();
        floatObject();
    }
}