// =============================================================================
// Core -> Mixins -> to-REM
// =============================================================================

@to-rem-font-size: @root-font-size;

//
// Convert unitless pixel values to rem.
//
// Usage
//
// .selector {
//   .to-rem(left, 1);
//   .to-rem(padding, 10 5 12);
//   .to-rem(border, 1, solid green);
//   .to-rem(box-shadow, 1 1 0 -1, rgba(0, 0, 0, 0.3));
//   .to-rem(margin, 30 auto 0);
// }
//
// @link http://cbrac.co/15UAPWx
//

.to-rem(@property, @size-values, @rest-link-params : false) {

  @property-rem: ~'/*rem*/'@property;
  @property-px: ~'/*px*/'@property;

  .to-rem-loop();

  .to-rem-loop(@amount : length(@size-values), @i : 1) when (@i =< @amount) {

    @size-value: extract(@size-values, @i);

    & when (iskeyword(@size-value)) {
      @px-value  : @size-value;
      @rem-value : @size-value;
      @{property-px}+_ : ~"@{px-value}";
      @{property-rem}+_ : ~"@{rem-value}";
    }

    & when not (iskeyword(@size-value)) {

      @px-value  : @size-value;
      @rem-value : @size-value / @to-rem-font-size;

      & when not (@px-value = 0) {
        @{property-px}+_ : ~"@{px-value}px";
      }

      & when (@px-value = 0) {
        @{property-px}+_ : @px-value;
      }

      & when not (@rem-value = 0) {
        @{property-rem}+_ : ~"@{rem-value}rem";
      }

      & when (@rem-value = 0) {
        @{property-rem}+_ : @rem-value;
      }

    }

    .to-rem-loop(@amount, (@i + 1));

  }

  & when not (@rest-link-params = false) {
    @{property-px}+_ : @rest-link-params;
  }

  & when not (@rest-link-params = false) {
    @{property-rem}+_ : @rest-link-params;
  }

}