@use 'sass:list';
@use 'sass:math';
@use 'sass:meta';
@use '../settings/globals';

///*------------------------------------*\
//    # REM
//\*------------------------------------*/
$gel-tools-rem-enable--function: true !default;
$gel-tools-rem-enable--mixin: true !default;
$gel-tools-rem-enable--fallback: true !default;

// 'rem' is a Sass function that converts pixel values to rem values
// for whatever property is passed to it.
//
// @param {Int}     $value - The unit you want converting to a rem unit
// @param {Int}     $baseline (globals.$gel-base-font-size) - The base font size of the page
//
// @return {Int}    The supplied converted to a rem unit
//
// @author          Kaelig - https://github.com/guardian/guss-rem
//
@function toRem($value, $baseline: globals.$gel-base-font-size) {
  // if function is disabled then return the value
  @if ($gel-tools-rem-enable--function == false) {
    @return $value;
  }

  @if $value == 0 {
    @return 0; // 0rem -> 0
  }

  @if meta.type-of($value) == list {
    $result: ();

    @each $e in $value {
      $result: list.append($result, toRem($e, $baseline));
    }

    @return $result;
  }

  @return if(
    sass(meta.type-of($value) == number and math.unit($value) == px): math.div($value, $baseline) *
      1rem; else: $value
  );
}

// Converts pixel values to rem values for whatever property is passed to it. It returns two
// lines of code — one of the regular pixel values (for old IE), and another with the
// converted rem values (for everyone else).
//
// @param {Int}     $property - The CSS property (e.g. font-size, margin-top)
// @param {Int}     $value - The pixel value you want to convert
//
// @author          Shaun Bent
//
@mixin toRem($property, $value) {
  // Return the pixel value first
  @if ($gel-tools-rem-enable--mixin == false or $gel-tools-rem-enable--fallback == true) {
    #{$property}: $value;
  }

  // Pass the px value into the rem function
  @if ($gel-tools-rem-enable--function == true and $gel-tools-rem-enable--mixin == true) {
    #{$property}: toRem($value);
  }
}