//
// Copyright 2021 Google LLC
// SPDX-License-Identifier: Apache-2.0
//

// go/keep-sorted start
@use 'sass:map';
@use 'sass:math';
// go/keep-sorted end
// go/keep-sorted start
@use '../../tokens';
// go/keep-sorted end

$_md-sys-motion: tokens.md-sys-motion-values();
// Duration of the label animation.
$_label-duration: map.get($_md-sys-motion, 'duration-short3');
// Duration of the content's visibility animation.
$_visible-duration: math.round(math.div($_label-duration * 5, 9));
// Short delay when entering (focusing/populating) so that the label may move
// out of the way before the content starts to appear.
$_enter-delay: $_label-duration - $_visible-duration;

@mixin styles() {
  .start,
  .middle,
  .end {
    display: flex;
    box-sizing: border-box;
    height: 100%;
    // Relative position for absolutely positioned labels (to avoid interfering
    // with baseline alignment).
    position: relative;
  }

  .start {
    color: var(--_leading-content-color);
  }

  .end {
    color: var(--_trailing-content-color);
  }

  .start,
  .end {
    align-items: center;
    justify-content: center;
  }

  // TODO(b/239188049): remove when layout tokens are ready
  .with-start .start,
  .with-end .end {
    min-width: 48px;
  }

  .with-start .start {
    margin-inline-end: 4px;
  }

  .with-end .end {
    margin-inline-start: 4px;
  }

  .middle {
    align-items: stretch;
    // The container of the field aligns sections by "center". Only the middle
    // section opts in to baseline alignment.
    //
    // Labels are absolutely positioned, which leaves only the content as the
    // evaluated baseline for the field.
    //
    // See https://www.w3.org/TR/css-flexbox-1/#baseline-participation
    align-self: baseline;
    flex: 1;
  }

  .content {
    color: var(--_content-color);
    display: flex;
    flex: 1;
    opacity: 0;
    transition: opacity $_visible-duration
      map.get($_md-sys-motion, 'easing-emphasized');
  }

  .no-label .content,
  .focused .content,
  .populated .content {
    opacity: 1;
    transition-delay: $_enter-delay;
  }

  :is(.disabled, .disable-transitions) .content {
    transition: none;
  }

  .content ::slotted(*) {
    all: unset;
    // Use `currentColor` to inherit the various state colors that are set
    // below.
    color: currentColor;
    font-family: var(--_content-font);
    font-size: var(--_content-size);
    line-height: var(--_content-line-height);
    font-weight: var(--_content-weight);
    width: 100%;
    white-space: pre-wrap; // Needed for Firefox textarea with "all: unset"
  }

  .content ::slotted(:not(textarea)) {
    padding-top: var(--_top-space);
    padding-bottom: var(--_bottom-space);
  }

  .content ::slotted(textarea) {
    // Use margin for textareas since they will scroll over the label if not.
    margin-top: var(--_top-space);
    margin-bottom: var(--_bottom-space);
  }

  :hover .content {
    color: var(--_hover-content-color);
  }

  :hover .start {
    color: var(--_hover-leading-content-color);
  }

  :hover .end {
    color: var(--_hover-trailing-content-color);
  }

  .focused .content {
    color: var(--_focus-content-color);
  }

  .focused .start {
    color: var(--_focus-leading-content-color);
  }

  .focused .end {
    color: var(--_focus-trailing-content-color);
  }

  .disabled .content {
    color: var(--_disabled-content-color);
  }

  .disabled.no-label .content,
  .disabled.focused .content,
  .disabled.populated .content {
    opacity: var(--_disabled-content-opacity);
  }

  .disabled .start {
    color: var(--_disabled-leading-content-color);
    opacity: var(--_disabled-leading-content-opacity);
  }

  .disabled .end {
    color: var(--_disabled-trailing-content-color);
    opacity: var(--_disabled-trailing-content-opacity);
  }

  .error .content {
    color: var(--_error-content-color);
  }

  .error .start {
    color: var(--_error-leading-content-color);
  }

  .error .end {
    color: var(--_error-trailing-content-color);
  }

  .error:hover .content {
    color: var(--_error-hover-content-color);
  }

  .error:hover .start {
    color: var(--_error-hover-leading-content-color);
  }

  .error:hover .end {
    color: var(--_error-hover-trailing-content-color);
  }

  .error.focused .content {
    color: var(--_error-focus-content-color);
  }

  .error.focused .start {
    color: var(--_error-focus-leading-content-color);
  }

  .error.focused .end {
    color: var(--_error-focus-trailing-content-color);
  }
}