_util.scss

@use "sass:list";
@use "sass:map";
@use "sass:meta";
@use "sass:string";
@use "../config" as config;
// Loaded for its side effect: the utility definitions merge into
// `config.$utilities`, which util() reads.
@use "../utilities"; // check-unused-imports-disable-line
@use "utilities" as gen;

// util() — emit a utility's base declarations into the current selector.
@mixin util($classes...) {
  @each $arg in $classes {
    @each $name in -util-split($arg) {
      $resolved: -util-resolve($name);

      @if $resolved == null {
        @error "util(): unknown utility class `#{$name}`";
      }

      // Never emit `!important`, even if the utility requests it.
      $utility: map.remove(map.get($resolved, "utility"), important);

      @include gen.generate-variables($utility, map.get($resolved, "value"));
      @include gen.generate-properties(
        $utility,
        map.get($resolved, "property-map"),
        map.get($resolved, "properties"),
        map.get($resolved, "value")
      );
    }
  }
}

// Flatten variadic args into a flat list, splitting space-separated strings.
@function -util-split($arg) {
  $result: ();

  @if meta.type-of($arg) == "list" {
    @each $item in $arg {
      @each $name in -util-split($item) {
        $result: list.append($result, $name);
      }
    }
  } @else if meta.type-of($arg) == "string" {
    @each $part in string.split($arg, " ") {
      @if $part != "" {
        $result: list.append($result, $part);
      }
    }
  } @else {
    $result: list.append($result, $arg);
  }

  @return $result;
}

// Find the utility and value that produce $name by mirroring the class-name
// construction in `generate-utility`. Returns a map of
// `(utility, property-map, properties, value)`, or null if no utility matches.
@function -util-resolve($name) {
  @each $key, $utility in config.$utilities {
    @if meta.type-of($utility) == "map" and map.get($utility, enabled) != false {
      // Attribute-selector utilities have no class-name form to match against.
      $selector-type: "class";
      @if map.has-key($utility, selector) {
        $selector-type: map.get($utility, selector);
      }

      @if $selector-type == "class" {
        $selector-class: map.get($utility, class);

        $values: map.get($utility, values);
        @if meta.type-of($values) != "map" {
          @if meta.type-of($values) == "list" {
            $list: ();
            @each $value in $values {
              $list: map.merge($list, ($value: $value));
            }
            $values: $list;
          } @else {
            $values: (null: $values);
          }
        }

        @each $value-key, $value in $values {
          $properties: map.get($utility, property);
          $property-map: null;
          $custom-class: "";

          @if meta.type-of($properties) == "map" {
            $property-map: $properties;
            @if map.has-key($utility, class) {
              $custom-class: map.get($utility, class);
            }
          } @else {
            @if meta.type-of($properties) == "string" {
              $properties: list.append((), $properties);
            }
            @if map.has-key($utility, class) {
              $custom-class: map.get($utility, class);
            } @else {
              $custom-class: list.nth($properties, 1);
            }
            @if $custom-class == null {
              $custom-class: "";
            }
          }

          $custom-class-modifier: "";
          @if $value-key {
            @if $custom-class == "" {
              $custom-class-modifier: $value-key;
            } @else {
              $custom-class-modifier: "-" + $value-key;
            }
          }

          $class-name: "";
          @if $custom-class != "" {
            $class-name: $custom-class + $custom-class-modifier;
          } @else if $selector-class != null and $selector-class != "" {
            $class-name: $selector-class + $custom-class-modifier;
          } @else {
            $class-name: $custom-class-modifier;
          }

          @if "#{$class-name}" == "#{$name}" {
            @return (
              "utility": $utility,
              "property-map": $property-map,
              "properties": $properties,
              "value": $value
            );
          }
        }
      }
    }
  }

  @return null;
}