@use "sass:meta";
@use "sass:math";

// @param  {Number}  $value
// @param  {Number}  $n
// @return {Number}

@function round-n($value, $n) {
  @return math.div(math.round($value * 10 * $n), (10 * $n));
}

// @param  {String}           $type
// @param  {Number|Function}  $fn
// @param  {Number}           $i
// @param  {Number}           $count
// @return {Number}

@function call-if-function($type, $fn, $i, $count) {
  @return if(meta.type-of($fn) == $type, $fn, call($fn, $i, $count));
}

// @param  {Boolean}          $inset
// @param  {Number|Function}  $x
// @param  {Number|Function}  $y
// @param  {Number|Function}  $blur-radius
// @param  {Number|Function}  $spread-radius
// @param  {Color|Function}   $color
// @param  {Number|Function}  $step
// @param  {Number|Function}  $stepX
// @param  {Number|Function}  $stepY
// @param  {Number}           $count
// @return {String}

@function box-shadow (
  $inset: false,
  $x: 0,
  $y: 0,
  $blur-radius: 0,
  $spread-radius: 0,
  $color: #000,
  $step: 0,
  $stepX: null,
  $stepY: null,
  $count: 1
) {

  $shadow: ();

  @if($stepX == null) {
    $stepX: $step;
  }
  @if($stepY == null) {
    $stepY: $step;
  }

  $_sum-stepX: 0;
  $_sum-stepY: 0;

  @for $i from 1 through $count {

    $_stepX: round-n(call-if-function("number", $stepX, $i, $count), 2);
    $_stepY: round-n(call-if-function("number", $stepY, $i, $count), 2);

    $_sum-stepX: $_sum-stepX + $_stepX;
    $_sum-stepY: $_sum-stepY + $_stepY;

    $_x: round-n(call-if-function("number", $x, $i, $count), 2);
    $_y: round-n(call-if-function("number", $y, $i, $count), 2);
    $_blur-radius: round-n(call-if-function("number", $blur-radius, $i, $count), 2);
    $_spread-radius: round-n(call-if-function("number", $spread-radius, $i, $count), 2);
    $_color: call-if-function("color", $color, $i, $count);

    $shadow: append($shadow, #{if($inset, "inset", "")} #{$_x + $_sum-stepX} #{$_y + $_sum-stepY} $_blur-radius $_spread-radius $_color, comma);
  }

  @return $shadow;
}

// @param  {Number|Function}  $x
// @param  {Number|Function}  $y
// @param  {Number|Function}  $blur-radius
// @param  {Color|Function}   $color
// @param  {Number|Function}  $step
// @param  {Number|Function}  $stepX
// @param  {Number|Function}  $stepY
// @param  {Number}           $count
// @return {String}

@function text-shadow (
  $x: 0,
  $y: 0,
  $blur-radius: 0,
  $color: #000,
  $step: 0,
  $stepX: null,
  $stepY: null,
  $count: 1
) {

  $shadow: ();

  @if($stepX == null) {
    $stepX: $step;
  }
  @if($stepY == null) {
    $stepY: $step;
  }

  $_sum-stepX: 0;
  $_sum-stepY: 0;

  @for $i from 1 through $count {

    $_stepX: round-n(call-if-function("number", $stepX, $i, $count), 2);
    $_stepY: round-n(call-if-function("number", $stepY, $i, $count), 2);

    $_sum-stepX: $_sum-stepX + $_stepX;
    $_sum-stepY: $_sum-stepY + $_stepY;

    $_x: round-n(call-if-function("number", $x, $i, $count), 2);
    $_y: round-n(call-if-function("number", $y, $i, $count), 2);
    $_blur-radius: round-n(call-if-function("number", $blur-radius, $i, $count), 2);
    $_color: call-if-function("color", $color, $i, $count);

    $shadow: append($shadow, #{$_x + $_sum-stepX} #{$_y + $_sum-stepY} $_blur-radius $_color, comma);
  }

  @return $shadow;
}