//
// Copyright IBM Corp. 2016, 2025
//
// This source code is licensed under the Apache-2.0 license found in the
// LICENSE file in the root directory of this source tree.
//

@use '../../button';
@use '../mixins' as *;
@use '../functions' as *;
@use '../../../breakpoint' as *;
@use '../../../config' as *;
@use '../../../layer' as *;
@use '../../../motion' as *;
@use '../../../spacing' as *;
@use '../../../theme' as *;
@use '../../../type' as *;
@use '../../../utilities/button-reset';
@use '../../../utilities/component-reset';
@use '../../../utilities/convert';
@use '../../../utilities/z-index' as *;

/// UI shell header
/// @access private
/// @group ui-shell
@mixin header {
  .#{$prefix}--header {
    @include component-reset.reset;

    position: fixed;
    z-index: z('header');
    display: flex;
    align-items: center;
    background-color: $background;
    block-size: mini-units(6);
    border-block-end: 1px solid $border-subtle;
    inset-block-start: 0;
    inset-inline: 0;
  }

  .#{$prefix}--header__action {
    @include button-reset.reset();

    display: inline-flex;
    border: convert.to-rem(1px) solid transparent;
    block-size: mini-units(6);
    inline-size: mini-units(6);
    transition:
      background-color $duration-fast-02,
      border-color $duration-fast-02;
    @include breakpoint-down('md') {
      min-inline-size: $spacing-09;
    }
  }

  .#{$prefix}--header__global .#{$prefix}--popover {
    z-index: z('header') + 1;
  }

  .#{$prefix}--header__action > :first-child {
    margin-block-start: 0;
  }

  .#{$prefix}--header__action
    > svg.#{$prefix}--navigation-menu-panel-collapse-icon,
  .#{$prefix}--header__action--active
    > svg.#{$prefix}--navigation-menu-panel-expand-icon {
    display: none;
  }

  .#{$prefix}--header__action--active
    > svg.#{$prefix}--navigation-menu-panel-collapse-icon {
    display: inline;
  }

  .#{$prefix}--header__action:hover {
    background-color: $background-hover;
  }

  .#{$prefix}--header__action--active {
    background: $layer;
    border-block-end: 1px solid transparent;
    border-inline-end: 1px solid $border-subtle;
    border-inline-start: 1px solid $border-subtle;
  }

  .#{$prefix}--header__action--active > svg {
    fill: $icon-primary;
  }

  .#{$prefix}--header__action:focus {
    border-color: $focus;
    outline: none;
  }

  .#{$prefix}--header__action:active {
    background-color: $background-active;
  }

  .#{$prefix}--header__action.#{$prefix}--btn--icon-only {
    align-items: center;
    justify-content: center;
  }

  .#{$prefix}--btn.#{$prefix}--btn--icon-only.#{$prefix}--header__action svg {
    fill: $icon-secondary;
  }

  .#{$prefix}--btn.#{$prefix}--btn--icon-only.#{$prefix}--header__action:hover
    svg,
  .#{$prefix}--btn.#{$prefix}--btn--icon-only.#{$prefix}--header__action:active
    svg,
  .#{$prefix}--btn.#{$prefix}--btn--icon-only.#{$prefix}--header__action--active
    svg {
    fill: $icon-primary;
  }

  .#{$prefix}--header__menu-trigger > svg {
    fill: $icon-primary;
  }

  .#{$prefix}--header__menu-trigger:hover > svg {
    fill: $icon-primary;
    // TODO: ask design if this color changes on hover, missing spec for it
  }

  .#{$prefix}--header__menu-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .#{$prefix}--header__menu-toggle__hidden {
    @include breakpoint('lg') {
      display: none;
    }
  }

  //--------------------------------------------------------------------------
  // Header - Name
  //--------------------------------------------------------------------------
  a.#{$prefix}--header__name {
    @include type-style('body-compact-01');

    display: flex;
    align-items: center;
    padding: 0 mini-units(4) 0 mini-units(2);
    border: convert.to-rem(2px) solid transparent;
    block-size: 100%;
    font-weight: 600;
    letter-spacing: 0.1px;
    line-height: 1.25rem;
    outline: none;
    text-decoration: none;
    transition: border-color $duration-fast-02;
    user-select: none;
    @include breakpoint-down('md') {
      padding: 0 $spacing-05;
    }
  }

  a.#{$prefix}--header__name:focus {
    border-color: $focus;
    // TODO: follow up with design to see if this is correct, missing focus spec for it
  }

  .#{$prefix}--header__name--prefix {
    font-weight: 400;
  }

  a.#{$prefix}--header__name,
  a.#{$prefix}--header__name:hover {
    color: $text-primary;
  }

  .#{$prefix}--header__menu-toggle:not(.#{$prefix}--header__menu-toggle__hidden)
    ~ .#{$prefix}--header__name {
    padding-inline-start: convert.to-rem(8px);
  }

  //--------------------------------------------------------------------------
  // Header - Navigation
  //--------------------------------------------------------------------------
  .#{$prefix}--header__nav {
    position: relative;
    display: none;
    block-size: 100%;
    padding-inline-start: mini-units(2);

    @include breakpoint('lg') {
      display: block;
    }

    // header nav divider
    &::before {
      position: absolute;
      display: block;
      background-color: $border-subtle;
      block-size: convert.to-rem(24px);
      content: '';
      inline-size: convert.to-rem(1px);
      inset-block-start: 50%;
      inset-inline-start: 0;
      transform: translateY(-50%);
    }
  }

  .#{$prefix}--header__menu-bar {
    @include component-reset.reset;

    display: flex;
    padding: 0;
    margin: 0;
    block-size: 100%;
    list-style: none;
  }

  a.#{$prefix}--header__menu-item {
    position: relative;
    display: flex;
    align-items: center;
    padding: 0 mini-units(2);
    // Used for focus styles
    border: 2px solid transparent;
    background-color: $background;
    // Used for links that are directly in the menubar to span the full height
    block-size: 100%;
    color: $text-secondary;
    // Text styles
    font-size: convert.to-rem(14px);
    font-weight: 400;
    letter-spacing: 0;
    line-height: 1.125rem;
    // Reset link styles and make sure the text isn't selectable
    text-decoration: none;
    transition:
      background-color $duration-fast-02,
      border-color $duration-fast-02,
      color $duration-fast-02;
    user-select: none;
  }

  a.#{$prefix}--header__menu-item:hover {
    background-color: $background-hover;
    color: $text-primary;
  }

  .#{$prefix}--header__action:active,
  a.#{$prefix}--header__menu-item:active {
    background-color: $background-active;
    color: $text-primary;
  }

  a.#{$prefix}--header__menu-item:focus {
    border-color: $focus;
    outline: none;
  }

  a.#{$prefix}--header__menu-item:hover > svg,
  a.#{$prefix}--header__menu-item:active > svg {
    fill: $icon-primary;
  }

  // Styles for selected state

  a.#{$prefix}--header__menu-item[aria-current='page'],
  .#{$prefix}--header__menu-item--current {
    color: $text-primary;
  }

  a.#{$prefix}--header__menu-item[aria-current='page']::after,
  .#{$prefix}--header__menu-item--current::after {
    position: absolute;
    background-color: $border-interactive;
    block-size: 3px;
    content: '';
    inline-size: calc(100% + 4px);
    inset-block-end: -2px;
    inset-inline-start: -2px;
  }

  a.#{$prefix}--header__menu-item[aria-current='page']:focus::after,
  .#{$prefix}--header__menu-item--current:focus::after {
    border: 0;
  }

  .#{$prefix}--header__submenu .#{$prefix}--header__menu {
    a.#{$prefix}--header__menu-item[aria-current='page']::after,
    .#{$prefix}--header__menu-item--current::after {
      background-color: $border-interactive;
      block-size: calc(100% + 4px);
      inline-size: 3px;
      inset-block-start: -2px;
      inset-inline-start: -2px;
    }

    a.#{$prefix}--header__menu-item[aria-current='page']:focus::after,
    .#{$prefix}--header__menu-item--current:focus::after {
      background-color: $border-interactive;
      block-size: calc(100% + 4px);
      // extra, hidden width prevents flickering on focus change
      inline-size: 5px;
      inset-block-start: -2px;
      inset-inline-start: -2px;
    }
  }

  a.#{$prefix}--header__menu-item[aria-current='page']:focus,
  a.#{$prefix}--header__menu-item.#{$prefix}--header__menu-item--current:focus {
    border: 2px solid $focus;
  }

  .#{$prefix}--header__submenu {
    position: relative;
  }

  .#{$prefix}--header__menu-title[aria-haspopup='true'] {
    position: relative;
  }

  .#{$prefix}--header__menu-title[aria-expanded='true'] {
    // Note: needs to be higher than menu. Adding 1 here instead of moving to
    // the next level.
    z-index: #{z('header') + 2};
    background-color: $layer;
    color: $text-secondary;
  }

  .#{$prefix}--header__menu-title[aria-expanded='true']
    > .#{$prefix}--header__menu-arrow {
    transform: rotate(180deg);
  }

  .#{$prefix}--header__menu {
    display: none;
    padding: 0;
    margin: 0;
    list-style: none;
  }

  .#{$prefix}--header__menu-title[aria-expanded='true']
    + .#{$prefix}--header__menu {
    position: absolute;
    z-index: #{z('header') + 1};
    display: flex;
    flex-direction: column;
    background-color: $layer;
    box-shadow: 0 4px 8px 0 rgb(0 0 0 / 50%);
    inline-size: mini-units(25);
    inset-block-end: 0;
    inset-inline-start: 0;
    transform: translateY(100%);
  }

  .#{$prefix}--header__menu-title[aria-expanded='true']
    + .#{$prefix}--header__menu
    .#{$prefix}--header__menu-item {
    background-color: $layer;
  }

  .#{$prefix}--header__menu-title[aria-expanded='true']
    + .#{$prefix}--header__menu
    .#{$prefix}--header__menu-item:hover {
    background-color: $layer-hover;
    color: $text-primary;
  }

  .#{$prefix}--header__menu-title[aria-expanded='true']
    + .#{$prefix}--header__menu
    .#{$prefix}--header__menu-item:active {
    background-color: $layer-active;
    color: $text-primary;
  }

  .#{$prefix}--header__menu-title[aria-expanded='true']
    + .#{$prefix}--header__menu
    .#{$prefix}--header__menu-item.#{$prefix}--header__menu-item--current {
    // used for both desktop and mobile
    background-color: $layer-selected;

    &:hover {
      background-color: $layer-selected-hover;
    }
  }

  .#{$prefix}--header__menu .#{$prefix}--header__menu-item {
    block-size: mini-units(6);
  }

  .#{$prefix}--header__menu-arrow {
    fill: $icon-secondary;
    margin-inline-start: mini-units(1);
    transition:
      transform $duration-fast-02,
      fill $duration-fast-02;
  }

  //--------------------------------------------------------------------------
  // Header - Global
  //--------------------------------------------------------------------------
  .#{$prefix}--header__global {
    display: flex;
    flex: 1 1 0%;
    justify-content: flex-end;
    block-size: 100%;
  }

  //--------------------------------------------------------------------------
  // Header - Skip to content
  //--------------------------------------------------------------------------
  .#{$prefix}--skip-to-content {
    position: absolute;
    overflow: hidden;
    padding: 0;
    border: 0;
    margin: -1px;
    block-size: 1px;
    clip: rect(0, 0, 0, 0);
    inline-size: 1px;
    visibility: inherit;
    white-space: nowrap;
  }

  .#{$prefix}--skip-to-content:focus {
    z-index: 9999;
    display: flex;
    align-items: center;
    padding: 0 1rem;
    border: 4px solid $focus;
    background-color: $background;
    block-size: 3rem;
    clip: auto;
    color: $text-secondary;
    inline-size: auto;
    inset-block-start: 0;
    inset-inline-start: 0;
    // TODO: double check with design that these tokens are correct, missing spec for it
    outline: none;
  }
}