/******************************************************
* MIXINS
******************************************************/

@function td-override-type-size($environment-name, $size, $font-size, $line-height) {
  	$typography: map-set-deep($typography, ("environments", $environment-name, "sizes", $size, "font-size"), $font-size);
  	$typography: map-set-deep($typography, ("environments", $environment-name, "sizes", $size, "line-height"), $line-height);
  	@return $typography;
}

@function td-get-font-size-adjustment($typeface-name, $opts: ()) {

  	// Extend default opts with passed opts.
	$opts: map-merge((
		"uppercase": false,
		"line-height": "normal"
	), $opts);

	// Apply font-size adjustment for the font passed.
	$font-size-adjustment: map-get-deep($typography, "typefaces", $typeface-name, "font-size-adjustment") or 1.00;

	// If uppercase option passed, also apply uppercase adjustment for the font passed.
	@if map-get($opts, "uppercase") {
		$uppercase-adjustment: map-get-deep($typography, "typefaces", $typeface-name, "uppercase-adjustment") or 1.00;
		$font-size-adjustment: $font-size-adjustment * $uppercase-adjustment;
	}

	@return $font-size-adjustment;
}

@function td-get-line-height-adjustment($typeface-name, $line-height, $opts: ()) {

  	// Extend default opts with passed opts.
	$opts: map-merge((
		"uppercase": false,
		"line-height": "normal"
	), $opts);

	// Calculate adjustments.
	$line-height-adjustment: map-get-deep($typography, "typefaces", $typeface-name, "line-height-adjustment") or 1.00;
	$font-size-adjustment: td-get-font-size-adjustment($typeface-name, $opts);

	// If using relative line heights, the font-size-adjustment will 
	// affect the line-height. This removes the unwanted effect.
	@if unitless($line-height) { 
		$line-height-adjustment: $line-height-adjustment * (1 / $font-size-adjustment);
	}

	@return $line-height-adjustment;
}


// Get adjusted font-size for specific font, environment, and size.
@mixin td-apply-adjusted-font-size($typeface-name, $size, $environment-name, $opts: ()) {

	// Extend default opts with passed opts.
	$opts: map-merge((
		"uppercase": false,
		"line-height": "normal"
	), $opts);
	
	// Default size.
	$font-size: map-get-deep($typography, "environments", $environment-name, "sizes", $size, "font-size"); 

	// Apply font-size adjustment for the font passed.
	$font-size-adjustment: td-get-font-size-adjustment($typeface-name, $opts);
	$font-size: $font-size * $font-size-adjustment;

	// Round final value.
	$font-size-precision: map-get-deep($typography, "environments", $environment-name, "font-size-precision") or null;
	@if ($font-size-precision) {
        $font-size: td-round($font-size, $font-size-precision);
    } 

	font-size: $font-size; 
}



// Get adjusted line-height for specific font, environment, and size.
@mixin td-apply-adjusted-line-height($typeface-name, $size, $environment-name, $opts: ()) {

	// Extend default opts with passed opts.
	$opts: map-merge((
		"uppercase": false,
		"line-height": "normal"
	), $opts);

	$line-height: null;

	// Normal line-height associated with environment and size.
	$normal-line-height: map-get-deep($typography, "environments", $environment-name, "sizes", $size, "line-height");

	// Solid line-height, meaning no space between lines. 
	// 1.0 if unitless, otherwise equal to font-size.
	$solid-line-height: if(unitless($normal-line-height), 1.0, $font-size);
	
	// Halfway between normal and solid line-height.
	$tight-line-height: (($normal-line-height - $solid-line-height) / 2) + $solid-line-height;


	$line-height-setting: map-get($opts, "line-height");
	$line-height-adjustment: td-get-line-height-adjustment($typeface-name, $normal-line-height, $opts);

	
	// Use solid line height, but don't apply adjustment.
	@if $line-height-setting == "solid" { 
		$line-height: $solid-line-height;

	// Use tight line-height and apply line-height adjustment.
	} @else if $line-height-setting == "tight" {
		$line-height: $tight-line-height * $line-height-adjustment;

	// Use normal line-height and apply line-height adjustment.
	} @else {
		$line-height: $normal-line-height * $line-height-adjustment;
	}

	// Round line-height.
	$line-height-precision: map-get-deep($typography, "environments", $environment-name, "line-height-precision") or null;
	@if ($line-height-precision) {
		$line-height: td-round($line-height, $line-height-precision);
	}

	line-height: $line-height;
}



// Apply styles for a specific font, environment, and size.
@mixin td-apply-adjusted-type-size($typeface-name, $size, $environment-name, $opts: ()) {

	// Extend default opts with passed opts.
	$opts: map-merge((
		"uppercase": false,
		"line-height": "normal"
	), $opts);

	@include td-apply-adjusted-font-size($typeface-name, $size, $environment-name, $opts);
	@include td-apply-adjusted-line-height($typeface-name, $size, $environment-name, $opts);
}


// Apply non-responsive styling. Only the size used for
// the specified environment will be applied.
@mixin td-type-size($typeface-name, $size, $environment-name, $opts: ()) {
	
	// Extend default opts with passed opts.
	$opts: map-merge((
		"uppercase": false,
		"line-height": "normal"
	), $opts);

	$media-query: map-get-deep($typography, "environments", $environment-name, "media-query");

	// If media query is null, apply styles w/o media query.
	@if $media-query == null {

		// Apply general styles.
		font-family: map-get-deep($typography, "typefaces", $typeface-name, "family");

		@if map-get($opts, "uppercase") {
			text-transform: uppercase;
		}
		
		@include td-apply-adjusted-type-size($typeface-name, $size, $environment-name, $opts);
	}

	// Otherwise, apply within media query.
	@else {
		@media #{$media-query} {
			@include td-apply-adjusted-type-size($typeface-name, $size, $environment-name, $opts);
		} 
	}
}


// Apply responsive styling. Unique font-size and line-height 
// will be applied for each environment.
@mixin td-responsive-type-size($typeface-name, $size: 0, $opts: ()) {
	
	// Extend default opts with passed opts.
	$opts: map-merge((
		"uppercase": false,
		"line-height": "normal"
	), $opts);

	// Apply type size (font-size and line-height) for each environment.
	@each $environment-name, $environment in map-get($typography, "environments") {
		@include td-type-size($typeface-name, $size, $environment-name, $opts);
	}
}