SwipeDetect "library"

function swipedetect(el, callback){

    var touchsurface = el,
    swipedir,
    startX,
    startY,
    distX,
    distY,
    threshold = 100, //required min distance traveled to be considered swipe
    restraint = 170, // maximum distance allowed at the same time in perpendicular direction
    allowedTime = 400, // maximum time allowed to travel that distance
    touchTime = 300,
    touchDist = 30,
    elapsedTime,
    startTime,
    handleswipe = callback || function(swipedir){}

    touchsurface.addEventListener('touchstart', function(e){
        var touchobj = e.changedTouches[0]
        swipedir = 'none'
        dist = 0
        startX = touchobj.pageX
        startY = touchobj.pageY
        startTime = new Date().getTime() // record time when finger first makes contact with surface
    }, false)

    touchsurface.addEventListener('touchend', function(e){
        var touchobj = e.changedTouches[0]
        distX = touchobj.pageX - startX // get horizontal dist traveled by finger while in contact with surface
        distY = touchobj.pageY - startY // get vertical dist traveled by finger while in contact with surface
        elapsedTime = new Date().getTime() - startTime // get time elapsed
        if (elapsedTime <= allowedTime){ // first condition for awipe met
            if (Math.abs(distX) >= threshold && Math.abs(distY) <= restraint){
                swipedir = (distX < 0)? 'left' : 'right'
                e.preventDefault();
                handleswipe(swipedir, touchobj.pageX, touchobj.pageY);
            } else if(elapsedTime <= touchTime) {
                if(Math.abs(distX) <= touchDist && Math.abs(distY) <= touchDist) swipedir = 'touch';
                handleswipe(swipedir, touchobj.pageX, touchobj.pageY);
            }
        }
    }, false)
}