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

// This is the default html and body font-size for the base rem value.
$rem-base: 16px !default;

// IMPORT ONCE
// We use this to prevent styles from being loaded multiple times for components that rely on other components.
$modules: () !default;

@mixin exports($name) {
  // Import from global scope
  $modules: $modules !global;
  // Check if a module is already on the list
  $module_index: index($modules, $name);
  @if (($module_index == null) or ($module_index == false)) {
    $modules: append($modules, $name) !global;
    @content;
  }
}

//
// @functions
//


// RANGES
// We use these functions to define ranges for various things, like media queries.
@function lower-bound($range) {
  @if length($range) <= 0 {
    @return 0;
  }
  @return nth($range, 1);
}

@function upper-bound($range) {
  @if length($range) < 2 {
    @return 999999999999;
  }
  @return nth($range, 2);
}

// STRIP UNIT
// It strips the unit of measure and returns it
@function strip-unit($num) {
  @return $num / ($num * 0 + 1);
}

// TEXT INPUT TYPES

@function text-inputs( $types: all, $selector: input ) {

  $return: ();

  $all-text-input-types:
    text
    password
    date
    datetime
    datetime-local
    month
    week
    email
    number
    search
    tel
    time
    url
    color
    textarea;

  @if $types == all { $types: $all-text-input-types; }

  @each $type in $types {
    @if $type == textarea {
      @if $selector == input {
        $return: append($return, unquote('#{$type}'), comma)
      } @else {
        $return: append($return, unquote('#{$type}#{$selector}'), comma)
      }
    } @else {
      $return: append($return, unquote('#{$selector}[type="#{$type}"]'), comma)
    }
  }

    @return $return;

}

// CONVERT TO REM
@function convert-to-rem($value, $base-value: $rem-base) {
  $value: strip-unit($value) / strip-unit($base-value) * 1rem;
  @if ($value == 0rem) { $value: 0; } // Turn 0rem into 0
  @return $value;
}

@function data($attr) {
  @if $namespace {
    @return '[data-' + $namespace + '-' + $attr + ']';
  }

  @return '[data-' + $attr + ']';
}

// REM CALC

// New Syntax, allows to optionally calculate on a different base value to counter compounding effect of rem's.
// Call with 1, 2, 3 or 4 parameters, 'px' is not required but supported:
//
//   rem-calc(10 20 30px 40);
//
// Space delimited, if you want to delimit using comma's, wrap it in another pair of brackets
//
//   rem-calc((10, 20, 30, 40px));
//
// Optionally call with a different base (eg: 8px) to calculate rem.
//
//   rem-calc(16px 32px 48px, 8px);
//
// If you require to comma separate your list
//
//   rem-calc((16px, 32px, 48), 8px);

@function rem-calc($values, $base-value: $rem-base) {
  $max: length($values);

  @if $max == 1 { @return convert-to-rem(nth($values, 1), $base-value); }

  $remValues: ();
  @for $i from 1 through $max {
    $remValues: append($remValues, convert-to-rem(nth($values, $i), $base-value));
  }
  @return $remValues;
}


@function em-calc($values, $base-value: $rem-base) {
  $remValues: rem-calc($values, $base-value: $rem-base);

  $max: length($remValues);

  @if $max == 1 { @return strip-unit(nth($remValues, 1)) * 1em; }

  $emValues: ();
  @for $i from 1 through $max {
    $emValues: append($emValues, strip-unit(nth($remValues, $i)) * 1em);
  }
  @return $emValues;
}


// Deprecated: OLD EM CALC
@function emCalc($values) {
  @return em-calc($values);
}

@function pow($Base, $Exponent) {

  // Find and remove unit.
  // Avoids messiness with unit calculations
  $Unit: $Base * 0 + 1;
  $Base: $Base/$Unit;

  // This function doesnt support non-interger exponents.
  // Warn the user about why this is breaking.
  @if round($Exponent) != $Exponent {
    @warn "Unfortunately, you can't use non-integer exponents.";
  }

  // Set up the loop, priming the return with the base.
  $Return: $Base;

  // If the number is positive, multiply it.
  @if $Exponent > 0 {
    // Basic feedback loop as exponents
    // are recursively multiplied numbers.
    @for $i from 1 to $Exponent {
      $Return: $Return * $Base;
    }
  }

  // If the number is 0 or negative
  // divide instead of multiply.
  @else {
    // Libsass doesnt allow negative values in loops
    @for $i from (-1 + 1) to (abs($Exponent) + 1) {
      $Return: $Return / $Base;
    }
  }

  // Return is now compounded ready to be returned.
  // Add the unit back onto the number.
  @return $Return * $Unit;
}


//  -------------------------------------------------
// Font scale function to return a number
// on a modular scale based on input
//  -------------------------------------------------
@function font-scale($scale: 0) {
  @return round($rem-base * pow($font-scale-ratio, $scale));
}


//  -------------------------------------------------
// Returns the `$light` color when the `$color` is dark
// and the `$dark` color when the `$color` is light.
// The `$threshold` is a percent between `0%` and `100%` and it determines
// when the lightness of `$color` changes from "dark" to "light".
//  -------------------------------------------------
@function contrast-color(
  $color,
  $dark: $contrasted-dark-default,
  $light: $contrasted-light-default,
  $threshold: $contrasted-lightness-threshold
) {
  @return if(lightness($color) < $threshold, $light, $dark)
}