// Name:            Skeleton
//
// Blocks:          `vk-skeleton-content`
//                  `vk-skeleton-title`
//                  `vk-skeleton-text`
//
// ========================================================================


// Variables
// ========================================================================

@skeleton-height:                                            8px;
@skeleton-spacing:                                           @global-small-margin;
@skeleton-line-height:                                       @global-line-height;

@skeleton-title-background:                                  darken(@global-muted-background, 10%);
@skeleton-content-background:                                darken(@global-muted-background, 3%);

@skeleton-animation-duration:                                1.5s;
@skeleton-animation-background:                              lighten(@skeleton-content-background, 3%);

@skeleton-border:                                            @global-border;
@skeleton-border-width:                                      @global-border-width;
@skeleton-border-radius:                                     3px;


/* ========================================================================
  Component
 ========================================================================== */

.vk-skeleton-content {
  position: relative;
  overflow: hidden;
  width: 100%;
  min-width: 10px;
  height: @skeleton-height;
  background: @skeleton-content-background;
  border-radius: @skeleton-border-radius;
  .vk-hook-skeleton-content;
}

.vk-skeleton--animated .vk-skeleton-content::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100vw;
  max-width: 1000px;
  height: 100%;
  background: linear-gradient(
    to right,
    transparent 0%,
    @skeleton-animation-background 15%,
    transparent 30%
  );
  animation-duration: @skeleton-animation-duration;
  animation-fill-mode: forwards;
  animation-iteration-count: infinite;
  animation-name: vkSkeletonAnimation;
  animation-timing-function: linear;
  .vk-hook-skeleton-content-animated;
}

/*
 * Animation
 */

@keyframes vkSkeletonAnimation {
  0% { transform: translate3d(-30%, 0, 0); }
  100% { transform: translate3d(100%, 0, 0); }
}

// Text
// ========================================================================

.vk-skeleton-text {
  display: inline-block;

  [class^="vk-skeleton-"] + & {
    margin-top: 2 * @skeleton-spacing;
  }

  &:nth-of-type(4n + 1) {
    width: 80%;
  }

  &:nth-of-type(4n + 2) {
    width: 100%;
  }

  &:nth-of-type(4n + 3) {
    width: 70%;
  }

  &:nth-of-type(4n + 4) {
    width: 85%;
  }

  &:only-of-type {
    width: 100%
  }
  .vk-hook-skeleton-text;
}

// Title & Subtitle
// ========================================================================

.vk-skeleton-title {
  width: 85%;
  display: inline-block;
  margin-bottom: @skeleton-spacing;

  .vk-skeleton-content {
    background: @skeleton-title-background;
  }
  .vk-hook-skeleton-title;
}

.vk-skeleton-title + .vk-skeleton-text {
  width: 90%;
  margin-top: 0;
}


// Image
// ========================================================================

.vk-skeleton-image {
  .vk-skeleton-content {
    height: 100%;
  }
  .vk-hook-skeleton-image;
}


// Hooks
// ========================================================================

.vk-hook-skeleton-misc;

.vk-hook-skeleton-content() {}
.vk-hook-skeleton-content-animated() {}
.vk-hook-skeleton-text() {}
.vk-hook-skeleton-image() {}
.vk-hook-skeleton-title() {}

.vk-hook-skeleton-misc() {}