@use 'sass:list';
@use 'sass:math';

$base-font-size: 16px !default;

@function strip-unit($num) {
  @return math.div($num, ($num * 0 + 1));
}

@function convert-to-em($value, $base: $base-font-size) {
  $value: math.div(strip-unit($value), strip-unit($base)) + 0em;
  @if ($value == 0em) {
    $value: 0;
  }
  @return $value;
}

@function convert-to-rem($value, $base: $base-font-size) {
  $value: math.div(strip-unit($value), strip-unit($base)) + 0rem;
  @if ($value == 0rem) {
    $value: 0;
  }
  @return $value;
}

@function convert-to-px($value, $base: $base-font-size) {
  $value: strip-unit($value) * strip-unit($base) + 0px;
  @if ($value == 0px) {
    $value: 0;
  }
  @return $value;
}

@function px($values, $base: $base-font-size) {
  $max: list.length($values);

  $px-values: ();
  @for $i from 1 through $max {
    $value: list.nth($values, $i);
    @if math.unit($value) != 'px' {
      $px-values: list.append($px-values, convert-to-px($value, $base));
    } @else {
      $px-values: list.append($px-values, $value);
    }
  }

  @if $max == 1 {
    $px-values: list.nth($px-values, 1);
  }

  @return $px-values;
}

@function rem($values, $base: $base-font-size) {
  $max: list.length($values);

  $rem-values: ();
  @for $i from 1 through $max {
    $value: list.nth($values, $i);
    @if math.unit($value) != 'rem' and math.unit($value) != 'em' {
      $rem-values: list.append($rem-values, convert-to-rem($value, $base));
    } @else {
      $rem-values: list.append($rem-values, $value);
    }
  }

  @if $max == 1 {
    $rem-values: list.nth($rem-values, 1);
  }

  @return $rem-values;
}

@function em($values, $base: $base-font-size) {
  $max: list.length($values);

  $em-values: ();
  @for $i from 1 through $max {
    $value: list.nth($values, $i);
    @if math.unit($value) != 'rem' and math.unit($value) != 'em' {
      $em-values: list.append($em-values, convert-to-em($value, $base));
    } @else {
      $em-values: list.append($em-values, $value);
    }
  }

  @if $max == 1 {
    $em-values: list.nth($em-values, 1);
  }

  @return $em-values;
}