/* --------------------------------------------------------------
 swiper.js 2017-08-03
 Gambio GmbH
 http://www.gambio.de
 Copyright (c) 2017 Gambio GmbH
 Released under the GNU General Public License (Version 2)
 [http://www.gnu.org/licenses/gpl-2.0.html]
 --------------------------------------------------------------
 */

/* globals Swiper */

/**
 * Widget that binds the swiper plugin (third party) to a DOM element
 *
 * @todo Remove the try - catch blocks and and correct the swiper issues.
 */
gambio.widgets.module(
    'swiper',

    [
        `${gambio.source}/libs/events`,
        `${gambio.source}/libs/responsive`
    ],

    function (data) {

        'use strict';

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

        var $this = $(this),
            $body = $('body'),
            $slides = null,
            $controls = null,
            $target = null,
            $theme = null,
            init = true,
            swiper = null,
            sliderOptions = null,
            hasThumbnails = true,
            mode = null,
            breakpointDataset = null,
            duplicates = false,
            preventSlideStart = false,
            sliderDefaults = {                                   // Default configuration for the swiper
                pagination: '.swiper-pagination',
                nextButton: '.swiper-button-next',
                prevButton: '.swiper-button-prev',
                paginationClickable: true,
                loop: true,
                autoplay: 3,
                autoplayDisableOnInteraction: false
            },
            defaults = {
                // JSON that gets merged with the sliderDefaults and is passed to "swiper" directly.
                sliderOptions: null,
                // If this instance is a "main" swiper, the given selector selects the "control" swiper.
                controls: null,
                // If this instance is a "control" swiper, the given selector selects the "main" swiper.
                target: null,
                // Sets the initial slide (needed to prevent different init slides in main/controller slider).
                initSlide: null,
                // Detect if a swiper is needed for the breakpoint. If not, turn it off
                autoOff: false,
                // The translucence fix enables support for a fade effect between images with different aspect ratio,
                // but causing a delay between the change
                disableTranslucenceFix: false,
                breakpoints: [
                    {
                        // Until which breakpoint this settings is available
                        breakpoint: 40,
                        // If true, the paging bullets will be replaced with the preview images.
                        usePreviewBullets: false,
                        // This and all other settings belonging to the swiper plugin.
                        slidesPerView: 2,
                        // If true, the current slide gets centered in view (most usefull with an even slidesPerView
                        // count).
                        centeredSlides: true
                    },
                    {
                        breakpoint: 60,
                        usePreviewBullets: true,
                        slidesPerView: 3
                    },
                    {
                        breakpoint: 80,
                        usePreviewBullets: true,
                        slidesPerView: 3
                    },
                    {
                        breakpoint: 100,
                        usePreviewBullets: true,
                        slidesPerView: 5
                    }
                ]
            },
            options = $.extend({}, defaults, data),
            module = {};


// ########## HELPER FUNCTIONS ##########

        /**
         * Function that generates the markup for
         * the preview bullets
         * @param       {Swiper}        swiper          Swiper object
         * @param       {integer}       index           Index of the slide
         * @param       {string}        className       The classname that must be add to the markup
         * @return      {string}                        The preview image html string
         * @private
         */
        var _generatePreviewButtons = function (swiper, index, className) {
            var $currentSlide = $slides.eq(index),
                $image = $currentSlide.find('img'),
                altTxt = $image.attr('alt'),
                thumbImage = $currentSlide.data('thumbImage');

            if (thumbImage) {
                return '<img src="' + thumbImage + '" alt="' + altTxt + '" class="' + className + '" />';
            }

            return '';
        };

        /**
         * Helper function to get the index of the
         * active slide
         * @return     {integer}                       The index of the active slide
         * @private
         */
        var _getIndex = function () {
            var index = $this
                .find('.swiper-slide-active')
                .index();

            // If there are duplicate slides (generated
            // by the swiper) recalculate the index
            index = duplicates ? index - 1 : index;
            index = index || 0;

            return index;
        };

        /**
         * Helper function to add the active
         * class to the active slide
         * @param       {integer}           index       The index of the active slide
         * @private
         */
        var _setActive = function (index) {
            $slides = $this.find('.swiper-slide:not(.swiper-slide-duplicate)');
            index = duplicates ? index + 1 : index;
            $slides
                .removeClass('active')
                .eq(index)
                .addClass('active');
        };


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

        /**
         * Event handler for the mouseenter event.
         * It disables the autoplay
         * @private
         */
        var _mouseEnterHandler = function () {
            try {
                if (swiper) {
                    swiper.stopAutoplay();
                }
            } catch (e) {
                // Do not log the error
            }
        };

        /**
         * Event handler for the mouseleave event.
         * It enables the autoplay
         * @private
         */
        var _mouseLeaveHandler = function () {
            try {
                if (swiper) {
                    swiper.startAutoplay();
                }
            } catch (e) {
                // Do not log the error
            }
        };

        /**
         * Event handler for the goto event.
         * It switches the current slide to the given index
         * and adds the active class to the new active slide
         * @param       {object}    e       jQuery event object
         * @param       {number}    d       Index of the slide to show
         * @private
         */
        var _gotoHandler = function (e, d) {
            e.stopPropagation();

            // Set the active slide
            _setActive(d);

            // Temporary deactivate the onSlideChangeStart event
            // to prevent looping through the goto / changeStart
            // events
            preventSlideStart = true;

            // Remove the autoplay after a goto event
            $this.off('mouseleave.swiper');
            swiper.stopAutoplay();

            // Try to correct the index between sliders
            // with and without duplicates
            var index = duplicates ? d + 1 : d;
            if (index > $slides.length) {
                index = 0;
            }

            // Goto the desired slide
            swiper.slideTo(index);

            // Reactivate the onSlideChangeEvent
            preventSlideStart = false;
        };

        /**
         * Click event handler that triggers a
         * "goto" event to the target swiper
         * @param       {object}        e       jQuery event object
         * @private
         */
        var _clickHandler = function (e) {
            e.preventDefault();
            e.stopPropagation();

            var $self = $(this),
                index = $self.index();

            index = duplicates ? index - 1 : index;

            // Set the active slide
            _setActive(index);

            // Inform the main swiper
            $target.trigger(jse.libs.theme.events.SWIPER_GOTO(), index);
        };

        /**
         * Event that gets triggered on slideChange.
         * If the slide gets changed, the controls
         * will follow the current slide in position
         * @private
         */
        var _triggerSlideChange = function () {
            if (!preventSlideStart) {
                var index = _getIndex(),
                    lastIndex = $slides.length - 2;


                // Recalculate index if duplicate slides are inside the slider
                if (index < 0) {
                    index = $slides.length - 3;
                } else {
                    index = (duplicates && index === lastIndex) ? index - lastIndex : index;
                }

                // Set the active slide
                _setActive(index);

                // Inform the controls
                $controls.trigger(jse.libs.theme.events.SWIPER_GOTO(), index);
            }
        };


        /**
         * Workaround for the translucence issue
         * that happens on small screens with enabled
         * fade effect. Maybe it can be removed, if the
         * swiper gets updated itself
         * @private
         */
        var _translucenceWorkaround = function () {
            if (!options.disableTranslucenceFix && sliderOptions && sliderOptions.effect === 'fade') {
                $this.find('.swiper-slide')
                    .filter(':not(.swiper-slide-active)')
                    .fadeTo(300, 0, function () {
                        $(this).css('visibility', 'hidden');
                    });

                $this.find('.swiper-slide')
                    .filter('.swiper-slide-active')
                    .fadeTo(300, 1, function () {
                        $(this).css('visibility', '');
                    });
            }
        };

        /**
         * The breakpoint handler initializes the swiper
         * with the settings for the current breakpoint.
         * Therefore it uses the default slider options,
         * the custom slider options given by the options
         * object and the breakpoint options object also
         * given by the options (in this order)
         * @private
         */
        var _breakpointHandler = function () {

            // Get the current viewmode
            var oldMode = mode || {},
                newMode = jse.libs.theme.responsive.breakpoint(),
                extendOptions = options.breakpoints[0] || {},
                newBreakpointDataset = null;

            // Only do something if the view was changed
            if (newMode.id !== oldMode.id) {

                // Store the new viewmode
                mode = $.extend({}, newMode);

                // Iterate through the breakpoints object to detect
                // the correct settings for the current breakpoint
                $.each(options.breakpoints, function (i, v) {
                    if (v.breakpoint > newMode.id) {
                        return false;
                    }
                    newBreakpointDataset = i;
                    extendOptions = v;
                });

                if (options.sliderOptions && options.sliderOptions.breakpoints) {
                    $.each(options.sliderOptions.breakpoints, function (i, v) {
                        if (v.breakpoint === newMode.id) {
                            extendOptions = v;
                            return false;
                        }
                    });
                }

                // Only do something if the settings change due browser
                // resize or if it's the first time run
                if (newBreakpointDataset !== breakpointDataset || init) {
                    // Combine the settings
                    sliderOptions = $.extend({}, sliderDefaults, options.sliderOptions || {}, extendOptions);

                    // Add the preview image bullets function to the options object
                    if (sliderOptions.usePreviewBullets && hasThumbnails) {
                        sliderOptions.paginationBulletRender = _generatePreviewButtons;
                    }

                    // Add the autoplay interval to the options object
                    sliderOptions.autoplay = (sliderOptions.autoplay) ? (sliderOptions.autoplay * 1000) : 0;

                    // Disable loop if there is only one slider. 
                    if ($this.find('.swiper-slide').length === 1) {
                        sliderOptions.loop = false;
                    }

                    // If an swiper exists, get the current
                    // slide no. and remove the old swiper
                    if (swiper) {
                        sliderOptions.initialSlide = _getIndex();
                        try {
                            swiper.destroy(true, true);
                        } catch (ignore) {
                            swiper = null;
                        }

                    } else {
                        sliderOptions.initialSlide = options.initSlide || sliderOptions.initialSlide || 0;
                    }

                    var $duplicate = $this.find('.swiper-slide:not(.swiper-slide-duplicate)');

                    if (!options.autoOff || ($duplicate.length > sliderOptions.slidesPerView && options.autoOff)) {
                        $this
                            .addClass('swiper-is-active')
                            .removeClass('swiper-is-not-active');

                        // Initialize the swiper
                        try {
                            swiper = new Swiper($this, sliderOptions);
                        } catch (e) {
                            return; // Swiper might throw an error upon initialization that should not halt the script execution.
                        }

                        swiper
                            .off('onTransitionEnd onSlideChangeStart')
                            .on('onTransitionEnd', _translucenceWorkaround);

                        // If this is a "main" swiper and has external controls, an
                        // goto event is triggered if the current slide is changed
                        if ($controls.length) {
                            swiper.on('onSlideChangeStart', _triggerSlideChange);
                        }

                        // Add the event handler
                        $this
                            .off('mouseenter.swiper mouseleave.swiper ' + jse.libs.theme.events.SWIPER_GOTO() + ' '
                                + jse.libs.theme.events.SLIDES_UPDATE())
                            .on('mouseenter.swiper', _mouseEnterHandler)
                            .on('mouseleave.swiper', _mouseLeaveHandler)
                            .on(jse.libs.theme.events.SWIPER_GOTO(), _gotoHandler)
                            .on(jse.libs.theme.events.SLIDES_UPDATE(), _updateSlides);

                        if (init) {
                            // Check if there are duplicates slides (generated by the swiper)
                            // after the first time init of the swiper
                            duplicates = !!$this.find('.swiper-slide-duplicate').length;
                        }

                        // Set the active slide
                        var index = (init && options.initSlide) ? options.initSlide : _getIndex();
                        _setActive(index);

                        // Inform the controls that the main swiper has changed
                        // In case that the other slider isn't initialized yet,
                        // set an data attribute to the markup element to inform
                        // it on init
                        if ($controls.length) {
                            $controls.attr('data-swiper-init-slide', index);
                            _triggerSlideChange();
                        }

                        // Unset the init flag
                        init = false;

                        setTimeout(() => swiper.update());
                    } else {
                        // Disable the swiper buttons
                        $this
                            .removeClass('swiper-is-active')
                            .addClass('swiper-is-not-active');
                        init = true;
                    }
                }

            }

        };

        /**
         * Event handler that adds & removes slides from the
         * swiper. After the slides were processed, the first
         * slide is shown
         * @param       {object}    e       jQuery event object
         * @param       {object}    d       JSON object that contains the categories / images
         * @private
         */
        var _updateSlides = function (e, d) {

            // Loops through each category inside the images array
            $.each(d, function (category, dataset) {
                var catName = category + '-category',
                    add = [],
                    remove = [],
                    markup = $theme.html();

                // Get all indexes from the slides
                // of the same category and remove
                // them from the slider
                $slides
                    .filter('.' + catName)
                    .each(function () {
                        var $self = $(this),
                            index = $self.data().swiperSlideIndex;

                        index = index === undefined ? $self.index() : index;
                        remove.push(index);
                    });
                swiper.removeSlide(remove);

                // Generate the markup for the new slides
                // and add them to the slider
                $.each(dataset || [], function (i, v) {
                    v.className = catName;
                    v.srcattr = 'src="' + v.src + '"';
                    add.push(Mustache.render(markup, v));
                });
                swiper.appendSlide(add);

            });

            $slides = $this.find('.swiper-slide');

            // To prevent an inconsistent state
            // in control / main slider combinations
            // slide to the first slide
            _setActive(0);
            var index = duplicates ? 1 : 0;
            swiper.slideTo(index, 0);

        };

        /**
         * Prevent text selection by clicking on swiper buttons
         * @private
         */
        var _preventTextSelection = function () {
            $(options.sliderOptions.nextButton).on('selectstart', function () {
                return false;
            });
            $(options.sliderOptions.prevButton).on('selectstart', function () {
                return false;
            });
        };

        /**
         * Sets the initial height for one swiper image container to prevent cut off images on smaller swiper heights
         * @private
         */
        var _scaleThumbnailHeight = function () {
            var swiperContainer = $('.swiper-container-vertical .swiper-slide');
            var $containerHeight = swiperContainer.css('height');


            // Workaround for IE Browsers
            if ($('.swiper-container-vertical').hasClass('swiper-wp8-vertical')) {
                $containerHeight = swiperContainer.height() + 5;

                swiperContainer.css('height', $containerHeight);
            }

            if ($containerHeight === '0px') {
                $containerHeight = $('.product-info-thumbnails-mobile').css('height');
            }

            $('.align-middle').css('height', $containerHeight);
        };

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

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

            $slides = $this.find('.swiper-slide');
            $controls = $(options.controls);
            $target = $(options.target);
            $theme = $this.find('theme');

            // Check if all images inside the swiper have
            // thumbnail image given
            $slides.each(function () {
                if (!$(this).data().thumbImage) {
                    hasThumbnails = false;
                    return false;
                }
            });

            // Add the breakpoint handler ty dynamically
            // set the options corresponding to the browser size (slider responsive will re-initialize the swiper).
            _breakpointHandler();

            // If this instance is a "control" swiper the target is the main swiper
            // which will be updated on a click inside this control swiper
            if (options.target) {
                $this.on('click.swiper', '.swiper-slide', _clickHandler);
            }

            $(document).ready(function () {
                $('.swiper-vertical .swiper-slide[data-index]').css('display', 'inline-block');
                $('.product-info-image .swiper-slide[data-index]').css('z-index', 'inherit');
                $('.product-info-image .swiper-slide[data-index] .swiper-slide-inside img.img-responsive').fadeIn(1000);
            });

            _translucenceWorkaround();
            _preventTextSelection();
            _scaleThumbnailHeight();

            // Fix for invisible Thumbnail-Images for switching from Tablet-Portrait to Tablet-Landscape
            $body.on(jse.libs.theme.events.BREAKPOINT(), function () {
                _scaleThumbnailHeight();
            });

            done();
        };

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