@use 'sass:math';

$grid-gutter-width: 16px;
$grid-columns: 12;
$grid-container: 'container';
$grid-row: 'row';
$grid-prefix: 'col';
$grid-sizes: (xs, sm, md, lg);
$grid-ratio-name: 'aspect';
$grid-ratio-inner-name: 'aspect__inner';
$grid-container-padding: (
  xs: 3.5%,
  sm: 7%,
);
$grid-max-width--desktop: 1200px;
$grid-ratios: ((16, 9), (9, 16), (4, 3), (3, 4), (3, 2), (3, 1), (2, 3), (2, 1), (1, 2), (1, 1));

// 7% => 0.07
$_grid-padding-pct: math.div(map-get($grid-container-padding, 'sm'), 100%);
// 0.07 => 0.14 => 0.86
$_grid-padding-value: 1 - $_grid-padding-pct * 2;

// Size of the window when the grid row has hit max-width.
$_viewport-at-max-grid-width: math.div($grid-max-width--desktop, $_grid-padding-value);
$viewport-at-max-grid-width: round($_viewport-at-max-grid-width) + 0px;
$padding-at-max-grid-width: round($_viewport-at-max-grid-width * $_grid-padding-pct) + 0px;

@function get-column-selector($number, $breakpoint) {
  @return '.#{$grid-prefix}-#{$number}\\@#{$breakpoint}';
}

@function get-grid-breakpoint-selectors($breakpoint) {
  $selectors: ();
  @for $i from 1 through $grid-columns {
    $selectors: append($selectors, get-column-selector($i, $breakpoint), comma);
  }

  @return $selectors;
}

@function get-all-grid-breakpoint-selectors() {
  $selectors: ();
  @each $breakpoint in $grid-sizes {
    $selectors: append($selectors, get-grid-breakpoint-selectors($breakpoint), comma);
  }

  @return $selectors;
}

@mixin make-grid-columns() {
  $selectors: get-all-grid-breakpoint-selectors();

  #{$selectors} {
    position: relative;
    box-sizing: border-box;
    // Prevent columns from collapsing when empty
    min-height: 1px;
    // Inner gutter via padding
    padding-left: ($grid-gutter-width * 0.5);
    padding-right: ($grid-gutter-width * 0.5);
  }
}

@mixin float-grid-columns($breakpoint) {
  $selectors: get-grid-breakpoint-selectors($breakpoint);

  #{$selectors} {
    float: left;
  }
}

@mixin grid-ratios($breakpoint: '') {
  // If there is a grid breakpoint class here, prepend a @.
  // e.g. "@sm" or "" when there isn't a class.
  @if $breakpoint != '' {
    $breakpoint: '\\@'+ $breakpoint;
  }

  // Note @extend isn't used because it cannot be used within @media directives.
  @each $list in $grid-ratios {
    $top: nth($list, 1);
    $bottom: nth($list, 2);
    $name: '#{$top}x#{$bottom}';
    .#{$grid-ratio-name}--#{$name}#{$breakpoint} {
      padding-bottom: percentage(math.div($bottom, $top));
    }
  }

  // A `none` class (eg `aspect--none@xs`) which removes the aspect ratio
  .#{$grid-ratio-name}--none#{$breakpoint} {
    @include no-aspect();

    > .#{$grid-ratio-inner-name} {
      position: static;
    }
  }
}

@mixin calc-grid-column($index, $columns, $breakpoint, $type) {
  @if ($type == 'width') and ($index > 0) {
    .#{$grid-prefix}-#{$index}\@#{$breakpoint} {
      width: percentage(math.div($index, $columns));
    }
  }
  @if ($type == 'push') and ($index > 0) {
    .#{$grid-prefix}-push-#{$index}\@#{$breakpoint} {
      left: percentage(math.div($index, $columns));
    }
  }
  @if ($type == 'push') and ($index == 0) {
    .#{$grid-prefix}-push-0\@#{$breakpoint} {
      left: auto;
    }
  }
  @if ($type == 'pull') and ($index > 0) {
    .#{$grid-prefix}-pull-#{$index}\@#{$breakpoint} {
      right: percentage(math.div($index, $columns));
    }
  }
  @if ($type == 'pull') and ($index == 0) {
    .#{$grid-prefix}-pull-0\@#{$breakpoint} {
      right: auto;
    }
  }
  @if ($type == 'offset') {
    .#{$grid-prefix}-offset-#{$index}\@#{$breakpoint} {
      margin-left: percentage(math.div($index, $columns));
    }
  }
}

@mixin loop-grid-columns($columns, $breakpoint, $type) {
  @for $i from 0 through $columns {
    @include calc-grid-column($i, $columns, $breakpoint, $type);
  }
}

// Create grid for specific class
@mixin make-grid($breakpoint, $columns: $grid-columns) {
  @include float-grid-columns($breakpoint);
  @include grid-ratios($breakpoint);

  @include loop-grid-columns($columns, $breakpoint, 'width');
  @include loop-grid-columns($columns, $breakpoint, 'pull');
  @include loop-grid-columns($columns, $breakpoint, 'push');
  @include loop-grid-columns($columns, $breakpoint, 'offset');
}