/* -------------------------------------
    Smart sticky
     -------------------------------------- */
(function (document, window, index) {
    'use strict';
    var elSelector = '.navbar',
        element = document.querySelector(elSelector);
    if (!element) return true;
    var elHeight = 0,
        elTop = 0,
        dHeight = 0,
        wHeight = 0,
        wScrollCurrent = 0,
        wScrollBefore = 0,
        wScrollDiff = 0;
    window.addEventListener('scroll', function () {
        elHeight = element.offsetHeight;
        dHeight = document.body.offsetHeight;
        wHeight = window.innerHeight;
        wScrollCurrent = window.pageYOffset;
        wScrollDiff = wScrollBefore - wScrollCurrent;
        elTop = parseInt(window.getComputedStyle(element).getPropertyValue('top')) + wScrollDiff;
        if (wScrollCurrent <= 0)
            // scrolled to the very top; element sticks to the top
            element.style.top = '0px';
        else if (wScrollDiff > 0)
            // scrolled up; element slides in
            element.style.top = (elTop > 0 ? 0 : elTop) + 'px';
        else if (wScrollDiff < 0) {
            // scrolled down
            if (wScrollCurrent + wHeight >= dHeight - elHeight)
                // scrolled to the very bottom; element slides in
                element.style.top = ((elTop = wScrollCurrent + wHeight - dHeight) < 0 ? elTop : 0) + 'px';
            // scrolled down; element slides out
            else element.style.top = (Math.abs(elTop) > elHeight ? -elHeight : elTop) + 'px';
        }
        wScrollBefore = wScrollCurrent;
    });
})(document, window, 0);
(function (document, window, index) {
    'use strict';
    var elSelector = '.navbar',
        element = document.querySelector(elSelector);
    if (!element) return true;
    var elHeight = 0,
        elTop = 0,
        dHeight = 0,
        wHeight = 0,
        wScrollCurrent = 0,
        wScrollBefore = 0,
        wScrollDiff = 0;
    window.addEventListener('scroll', function () {
        elHeight = element.offsetHeight;
        dHeight = document.body.offsetHeight;
        wHeight = window.innerHeight;
        wScrollCurrent = window.pageYOffset;
        wScrollDiff = wScrollBefore - wScrollCurrent;
        elTop = parseInt(window.getComputedStyle(element).getPropertyValue('top')) + wScrollDiff;
        if (wScrollCurrent <= 0) {
            // scrolled to the very top; element sticks to the top
            element.style.top = '0px';
            element.style.position = 'relative';
            $('.navbar').removeClass('navbar-stick');
        } else if (wScrollDiff > 0) {
            // scrolled up; element slides in
            element.style.top = (elTop > 0 ? 0 : elTop) + 'px';
            element.style.position = 'fixed';
            element.style.width = '100%';
            $('.navbar').addClass('navbar-stick');
        } else if (wScrollDiff < 0) {
            // scrolled down
            if (wScrollCurrent + wHeight >= dHeight - elHeight)
                // scrolled to the very bottom; element slides in
                element.style.top = ((elTop = wScrollCurrent + wHeight - dHeight) < 0 ? elTop : 0) + 'px';
            // scrolled down; element slides out
            else element.style.top = (Math.abs(elTop) > elHeight ? -elHeight : elTop) + 'px';
        }
        wScrollBefore = wScrollCurrent;
    });
})(document, window, 0);