<?php
/**
* Custom Colors Class
*
* @package WordPress
* @subpackage Twenty_Twenty_One
* @since Twenty Twenty-One 1.0
*/
/**
* This class is in charge of color customization via the Customizer.
*/
class Twenty_Twenty_One_Custom_Colors {
/**
* Instantiate the object.
*
* @access public
*
* @since Twenty Twenty-One 1.0
*/
public function __construct() {
// Enqueue color variables for customizer & frontend.
add_action( 'wp_enqueue_scripts', array( $this, 'custom_color_variables' ) );
// Enqueue color variables for editor.
add_action( 'enqueue_block_editor_assets', array( $this, 'editor_custom_color_variables' ) );
// Add body-class if needed.
add_filter( 'body_class', array( $this, 'body_class' ) );
}
/**
* Determine the luminance of the given color and then return #fff or #000 so that the text is always readable.
*
* @access public
*
* @param string $background_color The background color.
*
* @since Twenty Twenty-One 1.0
*
* @return string (hex color)
*/
public function custom_get_readable_color( $background_color ) {
return ( 127 < self::get_relative_luminance_from_hex( $background_color ) ) ? '#000' : '#fff';
}
/**
* Generate color variables.
*
* Adjust the color value of the CSS variables depending on the background color theme mod.
* Both text and link colors needs to be updated.
* The code below needs to be updated, because the colors are no longer theme mods.
*
* @access public
*
* @since Twenty Twenty-One 1.0
*
* @param string|null $context Can be "editor" or null.
*
* @return string
*/
public function generate_custom_color_variables( $context = null ) {
$theme_css = 'editor' === $context ? ':root .editor-styles-wrapper{' : ':root{';
$background_color = get_theme_mod( 'background_color', 'D1E4DD' );
if ( 'd1e4dd' !== strtolower( $background_color ) ) {
$theme_css .= '--global--color-background: #' . $background_color . ';';
$theme_css .= '--global--color-primary: ' . $this->custom_get_readable_color( $background_color ) . ';';
$theme_css .= '--global--color-secondary: ' . $this->custom_get_readable_color( $background_color ) . ';';
$theme_css .= '--button--color-background: ' . $this->custom_get_readable_color( $background_color ) . ';';
$theme_css .= '--button--color-text-hover: ' . $this->custom_get_readable_color( $background_color ) . ';';
if ( '#fff' === $this->custom_get_readable_color( $background_color ) ) {
$theme_css .= '--table--stripes-border-color: rgba(240, 240, 240, 0.15);';
$theme_css .= '--table--stripes-background-color: rgba(240, 240, 240, 0.15);';
}
}
$theme_css .= '}';
return $theme_css;
}
/**
* Customizer & frontend custom color variables.
*
* @access public
*
* @since Twenty Twenty-One 1.0
*
* @return void
*/
public function custom_color_variables() {
if ( 'd1e4dd' !== strtolower( get_theme_mod( 'background_color', 'D1E4DD' ) ) ) {
wp_add_inline_style( 'twenty-twenty-one-style', $this->generate_custom_color_variables() );
}
}
/**
* Editor custom color variables.
*
* @access public
*
* @since Twenty Twenty-One 1.0
*
* @return void
*/
public function editor_custom_color_variables() {
wp_enqueue_style(
'twenty-twenty-one-custom-color-overrides',
get_theme_file_uri( 'assets/css/custom-color-overrides.css' ),
array(),
(string) filemtime( get_theme_file_path( 'assets/css/custom-color-overrides.css' ) )
);
$background_color = get_theme_mod( 'background_color', 'D1E4DD' );
if ( 'd1e4dd' !== strtolower( $background_color ) ) {
wp_add_inline_style( 'twenty-twenty-one-custom-color-overrides', $this->generate_custom_color_variables( 'editor' ) );
}
}
/**
* Get luminance from a HEX color.
*
* @static
*
* @access public
*
* @since Twenty Twenty-One 1.0
*
* @param string $hex The HEX color.
*
* @return int Returns a number (0-255).
*/
public static function get_relative_luminance_from_hex( $hex ) {
// Remove the "#" symbol from the beginning of the color.
$hex = ltrim( $hex, '#' );
// Make sure there are 6 digits for the below calculations.
if ( 3 === strlen( $hex ) ) {
$hex = substr( $hex, 0, 1 ) . substr( $hex, 0, 1 ) . substr( $hex, 1, 1 ) . substr( $hex, 1, 1 ) . substr( $hex, 2, 1 ) . substr( $hex, 2, 1 );
}
// Get red, green, blue.
$red = hexdec( substr( $hex, 0, 2 ) );
$green = hexdec( substr( $hex, 2, 2 ) );
$blue = hexdec( substr( $hex, 4, 2 ) );
// Calculate the luminance.
$lum = ( 0.2126 * $red ) + ( 0.7152 * $green ) + ( 0.0722 * $blue );
return (int) round( $lum );
}
/**
* Adds a class to <body> if the background-color is dark.
*
* @access public
*
* @since Twenty Twenty-One 1.0
*
* @param array $classes The existing body classes.
*
* @return array
*/
public function body_class( $classes ) {
$background_color = get_theme_mod( 'background_color', 'D1E4DD' );
$luminance = self::get_relative_luminance_from_hex( $background_color );
if ( 127 > $luminance ) {
$classes[] = 'is-dark-theme';
} else {
$classes[] = 'is-light-theme';
}
if ( 225 <= $luminance ) {
$classes[] = 'has-background-white';
}
return $classes;
}
}