/*
===
4.2 Carousel
===

### Carousel

カルーセルを生成します。

#### HTML

```html
<ul class="carousel">
  <li>
    <img src="/assets/images/sample.jpg" alt="" />
  </li>
  <li>
    <img src="/assets/images/sample.jpg" alt="" />
  </li>
  <li>
    <img src="/assets/images/sample.jpg" alt="" />
  </li>
</ul>
```

#### JavaScript

第一引数にNodeを指定し、第二引数にパラメーターオブジェクトを指定します。

```js
document.addEventListener('DOMContentLoaded', () => {
  const $target = document.querySelector('.carousel');
  const param = {
    usePager: true,
    useControls: true,
    isAuto: true,
    animationDuration: 500,
    animationType: 'horizontal', // 'horizontal' or 'fade'
    pauseTime: 3000,
    onLoaded: function () {},
    onMoveBefore: function () {},
    onMoveAfter: function () {},
    onResized: function () {}
  });
  const carousel = new Frontwork.Carousel($target, param);
});
```

#### SCSS

カルーセルが読み込まれた時、スライドの切り替わり時に状態変化を示すクラスが追加されます。
それを利用して複雑なアニメーションを付与することができます。

```scss
.carousel,
.carousel > li {
  width: 100%;
  height: 100vh;
}
.carousel {
  opacity: 0;
  transition: opacity 1s ease-in-out;
}
.js-carousel.is-loaded {
  .carousel {
    opacity: 1;
  }
}
.carousel > li {
  transition: transform 0s linear 1s;
}
.js-carousel__item.is-show,
.js-carousel__item.is-leaving {
  .carousel > li {
    transform: scale(1.5);
    transition: transform 10s linear 0s;
  }
}
```

*/

.js-carousel {
  position: relative;
  overflow: hidden;
}

.js-carousel__slide {
  position: relative;
}

.js-carousel__item {
  width: 100%;
}

.js-carousel--fade {
  .js-carousel__slide {
    overflow: hidden;
  }

  .js-carousel__item {
    position: absolute;
    transition-property: opacity, visibility;
    transition-timing-function: linear, step-end;

    &.is-show {
      transition-duration: 0s, 0s !important;
    }
  }
}

.js-carousel--horizontal {
  transition: transform 0s ease-in-out;

  .js-carousel__slide {
    display: flex;
  }

  .js-carousel__item {
    display: flex;
    flex-shrink: 0;
    position: relative;
  }
}

.js-carousel__pager,
.js-carousel__prev,
.js-carousel__next {
  font-size: 0;
}

.js-carousel__pager {
  display: table;
  table-layout: fixed;
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  z-index: 5;
  list-style: none;
  padding-left: 0;
  margin-bottom: 0;
  padding-left: 1px;
  padding-right: 1px;

  & > li {
    display: table-cell;
    width: 100%;

    & > a {
      display: block;
      cursor: pointer;
      width: 100%;
      height: 30px;
      background-color: rgba(255, 255, 255, .5);
      border-left: 2px solid transparent;
      border-right: 2px solid transparent;
      border-top: 22px solid transparent;
      border-bottom: 3px solid transparent;
      background-clip: padding-box;

      &:hover {
        background-color: #fff;
      }

    }

    &.is-current > a {
      background-color: #fff;
    }

  }
}

.js-carousel__prev,
.js-carousel__next {
  display: block;
  position: absolute;
  top: 0;
  width: 15%;
  min-width: 50px;
  height: 100%;
  z-index: 4;
  overflow: hidden;
  cursor: pointer;

  &::before {
    content: '';
    display: block;
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
    margin: auto;
    width: 18px;
    height: 18px;
    border-left: 4px solid rgba(255, 255, 255, .5);
    border-bottom: 4px solid rgba(255, 255, 255, .5);
  }

  &:hover::before {
    border-left-color: #fff;
    border-bottom-color: #fff;
  }
}

.js-carousel__prev {
  left: 0;

  &::before {
    transform: rotate(45deg);
  }
}

.js-carousel__next {
  right: 0;

  &::before {
    transform: rotate(-135deg);
  }
}

.js-carousel__stop {
  display: block;
  font-size: 14px;
  line-height: 1.6;
  position: absolute;
  color: rgba(255, 255, 255, .5);
  border: 1px solid rgba(255, 255, 255, .5);
  padding: 2px 5px;
  top: 10px;
  right: 10px;
  z-index: 6;
  cursor: pointer;
  text-decoration: none;

  &:hover {
    color: #fff;
    border-color: #fff;
    text-decoration: none;
  }
}