import Util from './util';

/**
 * --------------------------------------------------------------------------
 * Bootstrap (v4.0.0-alpha.6): carousel.js
 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
 * --------------------------------------------------------------------------
 */

const Carousel = ($ => {

  /**
   * ------------------------------------------------------------------------
   * Constants
   * ------------------------------------------------------------------------
   */

  const NAME = 'carousel';
  const VERSION = '4.0.0-alpha.6';
  const DATA_KEY = 'bs.carousel';
  const EVENT_KEY = `.${DATA_KEY}`;
  const DATA_API_KEY = '.data-api';
  const JQUERY_NO_CONFLICT = $.fn[NAME];
  const TRANSITION_DURATION = 600;
  const ARROW_LEFT_KEYCODE = 37; // KeyboardEvent.which value for left arrow key
  const ARROW_RIGHT_KEYCODE = 39; // KeyboardEvent.which value for right arrow key

  const Default = {
    interval: 5000,
    keyboard: true,
    slide: false,
    pause: 'hover',
    wrap: true
  };

  const DefaultType = {
    interval: '(number|boolean)',
    keyboard: 'boolean',
    slide: '(boolean|string)',
    pause: '(string|boolean)',
    wrap: 'boolean'
  };

  const Direction = {
    NEXT: 'next',
    PREV: 'prev',
    LEFT: 'left',
    RIGHT: 'right'
  };

  const Event = {
    SLIDE: `slide${EVENT_KEY}`,
    SLID: `slid${EVENT_KEY}`,
    KEYDOWN: `keydown${EVENT_KEY}`,
    MOUSEENTER: `mouseenter${EVENT_KEY}`,
    MOUSELEAVE: `mouseleave${EVENT_KEY}`,
    LOAD_DATA_API: `load${EVENT_KEY}${DATA_API_KEY}`,
    CLICK_DATA_API: `click${EVENT_KEY}${DATA_API_KEY}`
  };

  const ClassName = {
    CAROUSEL: 'carousel',
    ACTIVE: 'active',
    SLIDE: 'slide',
    RIGHT: 'carousel-item-right',
    LEFT: 'carousel-item-left',
    NEXT: 'carousel-item-next',
    PREV: 'carousel-item-prev',
    ITEM: 'carousel-item'
  };

  const Selector = {
    ACTIVE: '.active',
    ACTIVE_ITEM: '.active.carousel-item',
    ITEM: '.carousel-item',
    NEXT_PREV: '.carousel-item-next, .carousel-item-prev',
    INDICATORS: '.carousel-indicators',
    DATA_SLIDE: '[data-slide], [data-slide-to]',
    DATA_RIDE: '[data-ride="carousel"]'
  };

  /**
   * ------------------------------------------------------------------------
   * Class Definition
   * ------------------------------------------------------------------------
   */

  class Carousel {

    constructor(element, config) {
      this._items = null;
      this._interval = null;
      this._activeElement = null;

      this._isPaused = false;
      this._isSliding = false;

      this._config = this._getConfig(config);
      this._element = $(element)[0];
      this._indicatorsElement = $(this._element).find(Selector.INDICATORS)[0];

      this._addEventListeners();
    }

    // getters

    static get VERSION() {
      return VERSION;
    }

    static get Default() {
      return Default;
    }

    // public

    next() {
      if (this._isSliding) {
        throw new Error('Carousel is sliding');
      }
      this._slide(Direction.NEXT);
    }

    nextWhenVisible() {
      // Don't call next when the page isn't visible
      if (!document.hidden) {
        this.next();
      }
    }

    prev() {
      if (this._isSliding) {
        throw new Error('Carousel is sliding');
      }
      this._slide(Direction.PREVIOUS);
    }

    pause(event) {
      if (!event) {
        this._isPaused = true;
      }

      if ($(this._element).find(Selector.NEXT_PREV)[0] && Util.supportsTransitionEnd()) {
        Util.triggerTransitionEnd(this._element);
        this.cycle(true);
      }

      clearInterval(this._interval);
      this._interval = null;
    }

    cycle(event) {
      if (!event) {
        this._isPaused = false;
      }

      if (this._interval) {
        clearInterval(this._interval);
        this._interval = null;
      }

      if (this._config.interval && !this._isPaused) {
        this._interval = setInterval((document.visibilityState ? this.nextWhenVisible : this.next).bind(this), this._config.interval);
      }
    }

    to(index) {
      this._activeElement = $(this._element).find(Selector.ACTIVE_ITEM)[0];

      const activeIndex = this._getItemIndex(this._activeElement);

      if (index > this._items.length - 1 || index < 0) {
        return;
      }

      if (this._isSliding) {
        $(this._element).one(Event.SLID, () => this.to(index));
        return;
      }

      if (activeIndex === index) {
        this.pause();
        this.cycle();
        return;
      }

      const direction = index > activeIndex ? Direction.NEXT : Direction.PREVIOUS;

      this._slide(direction, this._items[index]);
    }

    dispose() {
      $(this._element).off(EVENT_KEY);
      $.removeData(this._element, DATA_KEY);

      this._items = null;
      this._config = null;
      this._element = null;
      this._interval = null;
      this._isPaused = null;
      this._isSliding = null;
      this._activeElement = null;
      this._indicatorsElement = null;
    }

    // private

    _getConfig(config) {
      config = $.extend({}, Default, config);
      Util.typeCheckConfig(NAME, config, DefaultType);
      return config;
    }

    _addEventListeners() {
      if (this._config.keyboard) {
        $(this._element).on(Event.KEYDOWN, event => this._keydown(event));
      }

      if (this._config.pause === 'hover' && !('ontouchstart' in document.documentElement)) {
        $(this._element).on(Event.MOUSEENTER, event => this.pause(event)).on(Event.MOUSELEAVE, event => this.cycle(event));
      }
    }

    _keydown(event) {
      if (/input|textarea/i.test(event.target.tagName)) {
        return;
      }

      switch (event.which) {
        case ARROW_LEFT_KEYCODE:
          event.preventDefault();
          this.prev();
          break;
        case ARROW_RIGHT_KEYCODE:
          event.preventDefault();
          this.next();
          break;
        default:
          return;
      }
    }

    _getItemIndex(element) {
      this._items = $.makeArray($(element).parent().find(Selector.ITEM));
      return this._items.indexOf(element);
    }

    _getItemByDirection(direction, activeElement) {
      const isNextDirection = direction === Direction.NEXT;
      const isPrevDirection = direction === Direction.PREVIOUS;
      const activeIndex = this._getItemIndex(activeElement);
      const lastItemIndex = this._items.length - 1;
      const isGoingToWrap = isPrevDirection && activeIndex === 0 || isNextDirection && activeIndex === lastItemIndex;

      if (isGoingToWrap && !this._config.wrap) {
        return activeElement;
      }

      const delta = direction === Direction.PREVIOUS ? -1 : 1;
      const itemIndex = (activeIndex + delta) % this._items.length;

      return itemIndex === -1 ? this._items[this._items.length - 1] : this._items[itemIndex];
    }

    _triggerSlideEvent(relatedTarget, eventDirectionName) {
      const slideEvent = $.Event(Event.SLIDE, {
        relatedTarget,
        direction: eventDirectionName
      });

      $(this._element).trigger(slideEvent);

      return slideEvent;
    }

    _setActiveIndicatorElement(element) {
      if (this._indicatorsElement) {
        $(this._indicatorsElement).find(Selector.ACTIVE).removeClass(ClassName.ACTIVE);

        const nextIndicator = this._indicatorsElement.children[this._getItemIndex(element)];

        if (nextIndicator) {
          $(nextIndicator).addClass(ClassName.ACTIVE);
        }
      }
    }

    _slide(direction, element) {
      const activeElement = $(this._element).find(Selector.ACTIVE_ITEM)[0];
      const nextElement = element || activeElement && this._getItemByDirection(direction, activeElement);

      const isCycling = Boolean(this._interval);

      let directionalClassName;
      let orderClassName;
      let eventDirectionName;

      if (direction === Direction.NEXT) {
        directionalClassName = ClassName.LEFT;
        orderClassName = ClassName.NEXT;
        eventDirectionName = Direction.LEFT;
      } else {
        directionalClassName = ClassName.RIGHT;
        orderClassName = ClassName.PREV;
        eventDirectionName = Direction.RIGHT;
      }

      if (nextElement && $(nextElement).hasClass(ClassName.ACTIVE)) {
        this._isSliding = false;
        return;
      }

      const slideEvent = this._triggerSlideEvent(nextElement, eventDirectionName);
      if (slideEvent.isDefaultPrevented()) {
        return;
      }

      if (!activeElement || !nextElement) {
        // some weirdness is happening, so we bail
        return;
      }

      this._isSliding = true;

      if (isCycling) {
        this.pause();
      }

      this._setActiveIndicatorElement(nextElement);

      const slidEvent = $.Event(Event.SLID, {
        relatedTarget: nextElement,
        direction: eventDirectionName
      });

      if (Util.supportsTransitionEnd() && $(this._element).hasClass(ClassName.SLIDE)) {

        $(nextElement).addClass(orderClassName);

        Util.reflow(nextElement);

        $(activeElement).addClass(directionalClassName);
        $(nextElement).addClass(directionalClassName);

        $(activeElement).one(Util.TRANSITION_END, () => {
          $(nextElement).removeClass(`${directionalClassName} ${orderClassName}`).addClass(ClassName.ACTIVE);

          $(activeElement).removeClass(`${ClassName.ACTIVE} ${orderClassName} ${directionalClassName}`);

          this._isSliding = false;

          setTimeout(() => $(this._element).trigger(slidEvent), 0);
        }).emulateTransitionEnd(TRANSITION_DURATION);
      } else {
        $(activeElement).removeClass(ClassName.ACTIVE);
        $(nextElement).addClass(ClassName.ACTIVE);

        this._isSliding = false;
        $(this._element).trigger(slidEvent);
      }

      if (isCycling) {
        this.cycle();
      }
    }

    // static

    static _jQueryInterface(config) {
      return this.each(function () {
        let data = $(this).data(DATA_KEY);
        const _config = $.extend({}, Default, $(this).data());

        if (typeof config === 'object') {
          $.extend(_config, config);
        }

        const action = typeof config === 'string' ? config : _config.slide;

        if (!data) {
          data = new Carousel(this, _config);
          $(this).data(DATA_KEY, data);
        }

        if (typeof config === 'number') {
          data.to(config);
        } else if (typeof action === 'string') {
          if (data[action] === undefined) {
            throw new Error(`No method named "${action}"`);
          }
          data[action]();
        } else if (_config.interval) {
          data.pause();
          data.cycle();
        }
      });
    }

    static _dataApiClickHandler(event) {
      const selector = Util.getSelectorFromElement(this);

      if (!selector) {
        return;
      }

      const target = $(selector)[0];

      if (!target || !$(target).hasClass(ClassName.CAROUSEL)) {
        return;
      }

      const config = $.extend({}, $(target).data(), $(this).data());
      const slideIndex = this.getAttribute('data-slide-to');

      if (slideIndex) {
        config.interval = false;
      }

      Carousel._jQueryInterface.call($(target), config);

      if (slideIndex) {
        $(target).data(DATA_KEY).to(slideIndex);
      }

      event.preventDefault();
    }

  }

  /**
   * ------------------------------------------------------------------------
   * Data Api implementation
   * ------------------------------------------------------------------------
   */

  $(document).on(Event.CLICK_DATA_API, Selector.DATA_SLIDE, Carousel._dataApiClickHandler);

  $(window).on(Event.LOAD_DATA_API, () => {
    $(Selector.DATA_RIDE).each(function () {
      const $carousel = $(this);
      Carousel._jQueryInterface.call($carousel, $carousel.data());
    });
  });

  /**
   * ------------------------------------------------------------------------
   * jQuery
   * ------------------------------------------------------------------------
   */

  $.fn[NAME] = Carousel._jQueryInterface;
  $.fn[NAME].Constructor = Carousel;
  $.fn[NAME].noConflict = function () {
    $.fn[NAME] = JQUERY_NO_CONFLICT;
    return Carousel._jQueryInterface;
  };

  return Carousel;
})(jQuery);

export default Carousel;
//# sourceMappingURL=carousel.js.map