// Foundation for Sites by ZURB // foundation.zurb.com // Licensed under MIT Open Source

//// /// @group functions ////

$global-font-size: 100% !default;

/// Removes the unit (e.g. px, em, rem) from a value, returning the number only. /// /// @param {Number} $num - Number to strip unit from. /// /// @returns {Number} The same number, sans unit. @function strip-unit($num) {

@return $num / ($num * 0 + 1);

}

/// Converts one or more pixel values into matching rem values. /// /// @param {Number|List} $values - One or more values to convert. Be sure to separate them with spaces and not commas. If you need to convert a comma-separated list, wrap the list in parentheses. /// @param {Number} $base [null] - The base value to use when calculating the ‘rem`. If you’re using Foundation out of the box, this is 16px. If this parameter is ‘null`, the function will reference the `$base-font-size` variable as the base. /// /// @returns {List} A list of converted values. @function rem-calc($values, $base: null) {

$rem-values: ();
$count: length($values);

// If no base is defined, defer to the global font size
@if $base == null {
  $base: $global-font-size;
}

// If the base font size is a %, then multiply it by 16px
// This is because 100% font size = 16px in most all browsers
@if unit($base) == '%' {
  $base: ($base / 100%) * 16px;
}

// Using rem as base allows correct scaling
@if unit($base) == 'rem' {
  $base: strip-unit($base) * 16px;
}

@if $count == 1 {
  @return -zf-to-rem($values, $base);
}

@for $i from 1 through $count {
  $rem-values: append($rem-values, -zf-to-rem(nth($values, $i), $base));
}

@return $rem-values;

}

// Converts a unitless, pixel, or rem value to em, for use in breakpoints. @function -zf-bp-to-em($value) {

// Pixel and unitless values are converted to rems
@if unit($value) == 'px' or unitless($value) {
  $value: rem-calc($value, $base: 16px);
}

// Then the value is converted to ems
@return strip-unit($value) * 1em;

}

/// Converts a pixel value to matching rem value. Any value passed, regardless of unit, is assumed to be a pixel value. By default, the base pixel value used to calculate the rem value is taken from the ‘$global-font-size` variable. /// @access private /// /// @param {Number} $value - Pixel value to convert. /// @param {Number} $base [null] - Base for pixel conversion. /// /// @returns {Number} A number in rems, calculated based on the given value and the base pixel value. rem values are passed through as is. @function -zf-to-rem($value, $base: null) {

// Check if the value is a number
@if type-of($value) != 'number' {
  @warn inspect($value) + ' was passed to rem-calc(), which is not a number.';
  @return $value;
}

// Transform em into rem if someone hands over 'em's
@if unit($value) == 'em' {
  $value: strip-unit($value) * 1rem;
}

// Calculate rem if units for $value is not rem or em
@if unit($value) != 'rem' {
  $value: strip-unit($value) / strip-unit($base) * 1rem;
}

// Turn 0rem into 0
@if $value == 0rem {
  $value: 0;
}

@return $value;

}

/// Converts a pixel, percentage, rem or em value to a unitless value based on a given font size. Ideal for working out unitless line heights. /// /// @param {Number} $value - Value to convert to a unitless line height /// @param {Number} $base - The font size to use to work out the line height - defaults to $global-font-size /// /// @return {Number} - Unitless number @function unitless-calc($value, $base: null) {

// If no base is defined, defer to the global font size
@if $base == null {
  $base: $global-font-size;
}

// First, lets convert our $base to pixels

// If the base font size is a %, then multiply it by 16px
@if unit($base) == '%' {
  $base: ($base / 100%) * 16px;
}

@if unit($base) == 'rem' {
  $base: strip-unit($base) * 16px;
}

@if unit($base) == 'em' {
  $base: strip-unit($base) * 16px;
}

// Now lets convert our value to pixels too
@if unit($value) == '%' {
  $value: ($value / 100%) * $base;
}

@if unit($value) == 'rem' {
  $value: strip-unit($value) * $base;
}

@if unit($value) == 'em' {
  $value: strip-unit($value) * $base;
}

// 'px'
@if unit($value) == 'px' {
  @return strip-unit($value) / strip-unit($base);
}

// assume that line-heights greatern then 10 are meant to be absolute in 'px'
@if unitless($value) and ($value > 10) {
  @return $value / strip-unit($base);
}

@return $value;

}