@use 'sass:map';
@use 'sass:list';
@use '../core/tokens/m3-utils';
@use '../core/theming/theming';
@use '../core/tokens/m3';
@use '../core/style/elevation';

// The prefix used to generate the fully qualified name for tokens in this file.
$prefix: (mat, expansion);

/// Generates custom tokens for the mat-expansion.
@function get-tokens($theme: m3.$sys-theme) {
  $system: m3-utils.get-system($theme);

  @return (
    base: (
      expansion-container-shape: 12px,
      expansion-header-indicator-display: inline-block,
      expansion-legacy-header-indicator-display: none,
      expansion-container-elevation-shadow: elevation.get-box-shadow(2),
    ),
    color: (
      expansion-actions-divider-color: map.get($system, outline),
      expansion-container-background-color: map.get($system, surface),
      expansion-container-text-color: map.get($system, on-surface),
      expansion-header-description-color: map.get($system, on-surface-variant),
      expansion-header-disabled-state-text-color:
          m3-utils.color-with-opacity(map.get($system, on-surface), 38%),
      expansion-header-focus-state-layer-color: m3-utils.color-with-opacity(
          map.get($system, on-surface), map.get($system, focus-state-layer-opacity)),
      expansion-header-hover-state-layer-color: m3-utils.color-with-opacity(
          map.get($system, on-surface), map.get($system, hover-state-layer-opacity)),
      expansion-header-indicator-color: map.get($system, on-surface-variant),
      expansion-header-text-color: map.get($system, on-surface),
    ),
    typography: (
      expansion-container-text-font: map.get($system, body-large-font),
      expansion-container-text-line-height: map.get($system, body-large-line-height),
      expansion-container-text-size: map.get($system, body-large-size),
      expansion-container-text-tracking: map.get($system, body-large-tracking),
      expansion-container-text-weight: map.get($system, body-large-weight),
      expansion-header-text-font: map.get($system, title-medium-font),
      expansion-header-text-line-height: map.get($system, title-medium-line-height),
      expansion-header-text-size: map.get($system, title-medium-size),
      expansion-header-text-tracking: map.get($system, title-medium-tracking),
      expansion-header-text-weight: map.get($system, title-medium-weight),
    ),
    density: get-density-tokens(map.get($system, density-scale)),
  );
}

// Tokens that can be configured through Angular Material's density theming API.
@function get-density-tokens($scale) {
  $scale: theming.clamp-density($scale, -3);
  $index: ($scale * -1) + 1;

  @return (
    expansion-header-collapsed-state-height: list.nth((48px, 44px, 40px, 36px), $index),
    expansion-header-expanded-state-height: list.nth((64px, 60px, 56px, 48px), $index),
  );
}