_testi.scss

$testi_debug: false;

// returns a copy of the array with all falsy values removed
@function _testi_compact($list) {
  @each $key, $value in $list {
    @if $value == null or $value == "" {
      $list: map-remove($list, $key);
    }
  }
  @return $list;
}

// merge recursively two lists
@function _testi_merge($parent-map, $child-map) {
  $result: $parent-map;
  @each $key, $value in $child-map {
    @if (not map-has-key($result, $key)) or (type-of(map-get($result, $key)) != type-of($value)) or (not (type-of(map-get($result, $key)) == map and type-of($value) == map)) {
      $result: map-merge($result, ($key: $value));
    } @else {
      $result: map-merge($result, ($key: _testi_merge(map-get($result, $key), $value)));
    }
  }
  @return $result;
}

// return a preset object according to the given key
@function _testi_getPreset($key) {
  @if map-has-key($testi, $key) {
    @return map-get($testi, $key);
  }
  @return null;
}

// return the style object according to the given key
@function _tetsi_getStyle($presetKey) {
  $style: _testi_getPreset($presetKey);
  @if $style != null {
    $extend: _tetsi_getStyle(map-get($style, "extend"));
    $style: map-remove($style, "extend");
    $style: map-merge((
      antialiased: true
    ), _testi_merge($extend, $style));
    @return $style;
  } @else {
    @return ();
  }
}

// apply a list of css rules
@mixin applyStyle($style) {
  @each $key, $value in $style {
    @if $key == 'antialiased' {
      @if $value == true {
        -webkit-font-smoothing: antialiased;
        -moz-font-smoothing: antialiased;
        -o-font-smoothing: antialiased;
        font-smoothing: antialiased;
      }
    } @else if $key == 'mq' {
      @each $breakpoint, $style in map-get($style, 'mq') {
        @if mixin-exists('respond-to') and map-has-key(get-breakpoint(), $breakpoint) {
          @include respond-to(#{$breakpoint}) {
            @include applyStyle($style);
          }
        } @else if mixin-exists('mq') and map-has-key($mq-breakpoints, $breakpoint)  {
          @include mq($from: #{$breakpoint}) {
            @include applyStyle($style);
          }
        } @else {
          @media #{$breakpoint} {
            @include applyStyle($style);
          }
        }
      }
    } @else {
      #{$key}: $value;
    }
  }
}

@mixin testi($a:null, $b:null, $c:null, $d:null, $e:null) {
  @if global-variable-exists(testi) AND type-of($testi) == 'map' {
    @if type-of($a) == 'string' {
      @if map-has-key($testi, $a) {
        // extend default style with a preset
        $style: _tetsi_getStyle($a);

        // extend style with the given arguments
        $style: map-merge($style, _testi_compact((
          font-size: $b,
          line-height: $c,
          font-weight: $d,
          letter-spacing: $e
        )));

        // set style
        @include applyStyle($style);

        @if $testi_debug == true {
          &:before {
            content: '#{$a}';
            display: block;
            max-width: 300px;
            font-family: Arial;
            font-weight: bold;
            padding: 2px;
            font-size: 10px;
            line-height: 9px;
            color: black;
            background: #00ff30;
            font-family: Arial;
            position: relative;
            text-transform: uppercase;
            letter-spacing: 0em;
          }
        }
      } @else {
        @warn 'Preset "#{$a}" not found; available presets: #{map-keys($testi)}';
      }
    } @else {
      @warn 'Text mixin require a preset name as first argument; available presets: #{map-keys($testi)}';
    }
  } @else {
    @warn '"$testi" variable not found';
  }
}