/**
 * Test an argument passed to a function or a mixin to ensure his type, value, etc...
 * If the argument does not pass the test, an error will be thrown, unless the $check-only argument is true
 *
 * @param 				{String} 				$method 				The function/mixin name (debug purpose)
 * @param 				{String} 				$argument 				The argument name to test (debug purpose)
 * @param 				{List|String} 			$type-or-values 		If string, the type(s) that the argument must match, if list, the possible values that the argument can take
 * @param 				{Mixed} 				$value 					The actual argument value
 * @param 				{Boolean} 				[$check-only=false]		If this is true, will not thrown any error
 * @return 				{Mixed} 										The value if ok, false if not
 *
 * @example
 * \@mixin my-cool-mixin($argument1, $argument2) {
 *        $argument1 : s-test-argument(my-cool-mixin, argument1, string, $argument1);
 *        $argument2 : s-test-argument(my-cool-mixin, argument2, (hello,world,12), $argument2);
 * }
 * \@mixin my-cool-mixin(hello, world); // ok
 * \@mixin my-cool-mixin(hello, universe); // throw an error
 * \@mixin my-cool-mixin(12, world); // throw an error
 *
 * @author 				Olivier Bossel <olivier.bossel@gmail.com> (https://olivierbossel.com)
 */
@function s-test-argument(
  $method,
  $argument,
  $type-or-values,
  $value,
  $check-only: false
) {
  // check if not value
  @if not $value {
    @return $value;
  }
  // check explicit values
  @if type-of($type-or-values) == string {
    // check the type
    @if not s-is($value, $type-or-values) {
      @if $check-only {
        @return false;
      }
      @error ('The property "#{$argument}" of the mixin/function "#{$method}" need to be a "#{$type-or-values}" but it seems that you pass a "#{type-of($value)}" : #{$value}');
    }
    @return $value;
  } @else if type-of($type-or-values) == list {
    // check if the passed value exist in possible values
    @if type-of($value) == list and index($type-or-values, length) {
      @return $value;
    } @else if type-of($value) == number and index($type-or-values, number) {
      @return $value;
    } @else {
      // if its a list of values, check each values
      @if type-of($value) == list {
        @each $v in $value {
          @if not _s-check-property($argument, $type-or-values, $v, true) {
            @return false;
          }
        }
        @return $value;
      } @else {
        $idx: index($type-or-values, $value);
        @if not $idx {
          @if not $check-only {
            @error ('The property "#{$argument}" or the mixin/function "#{$method}" has to be one of these values "#{$type-or-values}" and not "#{$value}"');
          }
          @return false;
        }
        $v: nth($type-or-values, $idx);
        @if type-of($v) == type-of($value) {
          @if type-of($v) == number {
            @if unit($v) == unit($value) {
              @if not $check-only {
                @error ('The property "#{$argument}" or the mixin/function "#{$method}" has to be one of these values "#{$type-or-values}" and not "#{$value}"');
              }
              @return $value;
            } @else {
              @return false;
            }
          } @else {
            @return $value;
          }
        } @else {
          @if not $check-only {
            @error ('The property "#{$argument}" or the mixin/function "#{$method}" has to be one of these values "#{$type-or-values}" and not "#{$value}"');
          }
          @return false;
        }
        @return $value;
      }
    }
  } @else {
    @return $value;
  }
  @if not $check-only {
    @error ('The property "#{$argument}" or the mixin/function "#{$method}" is wrong');
  }
  @return false;
}