/* --------------------------------------------------------------
 header.js 2016-03-09
 Gambio GmbH
 http://www.gambio.de
 Copyright (c) 2015 Gambio GmbH
 Released under the GNU General Public License (Version 2)
 [http://www.gnu.org/licenses/gpl-2.0.html]
 --------------------------------------------------------------
 */

/**
 * Widget that adds a class to a defined object if the page is
 * scrolled to a given position at least. It is used to set
 * the header size
 */
gambio.widgets.module(
    'header',

    [
        gambio.source + '/libs/events'
    ],

    function (data) {

        'use strict';

// ########## VARIABLE INITIALIZATION ##########

        var $this = $(this),
            $window = $(window),
            $header = null,
            hover = false,
            currentPosition = null,
            scrollUpCounter = 0,
            transition = {},
            timeout = 0,
            defaults = {
                // Selector that defines the header element
                header: '#header',
                // Position in px that needs to be reached to minimize the header
                scrollPosition: 200,
                // Class that gets added if the scrollPosition gets reached
                stickyClass: 'sticky',
                // Maximize the target on mouse hover
                hover: false,
                // Tolerance in px that is used to detect scrolling up
                tolerance: 5
            },
            options = $.extend(true, {}, defaults, data),
            module = {};


// ########## EVENT HANDLER ##########

        /**
         * Handler that gets called by scrolling down / up
         * the site. If the position is lower than the
         * scrollPosition from options, the header gets maximized
         * else it gets minimized
         * @private
         */
        var _scrollHandler = function () {
            var position = $(document).scrollTop(),
                hasClass = $header.hasClass(options.stickyClass),
                scrollUp = currentPosition > position;

            if (position > options.scrollPosition && !scrollUp) {
                // Proceed if scrolling down under the minimum position given by the options
                scrollUpCounter = 0;
                if (!hasClass && !hover) {
                    // Proceed if the class isn't set yet and the header isn't hovered with the mouse
                    transition.open = false;
                    $header
                        .trigger(jse.libs.theme.events.TRANSITION(), transition)
                        .trigger(jse.libs.theme.events.OPEN_FLYOUT(), [$this]);
                }
            } else {
                scrollUpCounter += 1;
                if (hasClass && (options.scrollPosition > position || scrollUpCounter > options.tolerance)) {
                    // Proceed if the the minimum position set in the option isn't reached
                    // or a specific count of pixel is scrolled up
                    transition.open = true;
                    $header.trigger(jse.libs.theme.events.TRANSITION(), transition);
                }
            }

            clearTimeout(timeout);
            timeout = setTimeout(function () {
                $window.trigger(jse.libs.theme.events.REPOSITIONS_STICKYBOX());
            }, 250);

            // Store the current position
            currentPosition = position;
        };

        /**
         * Handler for the mouseenter event on the
         * header. It will remove the minimizer-class
         * from the header container and set the internal
         * header hover state to true
         * @private
         */
        var _mouseEnterHandler = function () {
            hover = true;
            transition.open = true;
            $header.trigger(jse.libs.theme.events.TRANSITION(), transition);
        };

        /**
         * Handler for the mouseout event on the header
         * container. On mouse out, the hover state will
         * be set to false, and the header state will be
         * set by the current scroll position
         * @private
         */
        var _mouseOutHandler = function () {
            hover = false;
            _scrollHandler();
        };


// ########## INITIALIZATION ##########

        /**
         * Init function of the widget
         * @constructor
         */
        module.init = function (done) {

            $header = $this.find(options.header);
            currentPosition = $(document).scrollTop();
            transition.classClose = options.stickyClass;

            $window.on('scroll', _scrollHandler);

            // Add event handler for the mouseover events
            // this can cause problems with flickering menus!
            if (options.hover) {
                $header
                    .on('mouseenter', _mouseEnterHandler)
                    .on('mouseleave', _mouseOutHandler);
            }

            // Set the initial state of the header
            _scrollHandler();

            done();
        };

        // Return data to widget engine
        return module;
    });