ATF Custom Brand Colors

code.php

<?php
/**
 * WPE Brand bootstrap (users_brand → Brand post → CSS vars)
 *
 * Rules:
 *   - Post Type: "Brand"
 *   - User profile meta: users_brand (int Brand post ID)
 *   - Brand meta:
 *       - brand_primary_color     -> --brand-primary
 *       - brand_secondary_color   -> --brand-secondary
 *       - brand_tertiary_color    -> --brand-tertiary
 */

add_action( 'init', 'wpe_brand_load_users_brand_global' );

/**
 * Load the current user's Brand (by users_brand post ID) into $wpe_brand and emit CSS vars.
 *
 * @param int $user_id Optional specific user ID; defaults to current user.
 * @return array|null
 */
function wpe_brand_load_users_brand_global( $user_id = 0 ) {
	global $wpe_brand;

	$wpe_brand = null;

	// Resolve user
	if ( ! $user_id ) {
		$user_id = get_current_user_id();
	}

	if ( ! $user_id ) {
		return null;
	}

	// Read the Brand post ID from user meta (users_brand)
	$brand_id = get_user_meta( $user_id, 'users_brand', true );
	if ( $brand_id === '' || $brand_id === null ) {
		return null;
	}
	
	$brand_id = absint( $brand_id );
	if ( ! $brand_id ) {
		return null;
	}

	// Load the Brand post (micro-cached)
	$brand_post = wpe_brand_find_brand_by_id( $brand_id );
	

	if ( ! ( $brand_post instanceof WP_Post ) ) {
		return null;
	}

	// Core info
	$core = array(
		'ID'        => $brand_post->ID,
		'post_type' => $brand_post->post_type,
		'status'    => $brand_post->post_status,
		'slug'      => $brand_post->post_name,
		'title'     => get_the_title( $brand_post ),
		'permalink' => get_permalink( $brand_post ),
	);

	

	// Post meta (normalized to key => value/array)
	$raw_meta = get_post_meta( $brand_post->ID );
	$meta     = array();
	foreach ( $raw_meta as $key => $vals ) {
		$meta[ $key ] = count( $vals ) === 1 ? maybe_unserialize( $vals[0] ) : array_map( 'maybe_unserialize', $vals );
	}

	// Optional: ACF can be heavy; only load if you need it somewhere else.
	$acf_fields = array(); // intentionally empty to avoid overhead

	$wpe_brand = array(
		'core' => $core,
		'acf'  => $acf_fields,
		'meta' => $meta,
		'post' => $brand_post,
	);

	// Emit CSS vars from Brand colors
	if ( function_exists( 'wpe_brand_parse_users_brand' ) ) {
		wpe_brand_parse_users_brand( $wpe_brand );
	} else {
		wpe_brand_print_brand_colors_head( $meta );
	}

	return $wpe_brand;
}

/**
 * Find a Brand post by ID, ensuring correct post_type/status.
 * Micro-cached per request.
 */
function wpe_brand_find_brand_by_id( int $brand_id ): ?WP_Post {
	static $cache = array();

	if ( isset( $cache[ $brand_id ] ) ) {
		return $cache[ $brand_id ];
	}

	$post = get_post( $brand_id );

	if ( ! ( $post instanceof WP_Post ) ) {
		return $cache[ $brand_id ] = null;
	}
	// Ensure it is a published Brand
	if ( $post->post_type !== 'brand' || $post->post_status !== 'publish' ) {
		return $cache[ $brand_id ] = null;
	}

	return $cache[ $brand_id ] = $post;
}

/**
 * Hook point to parse the user's Brand structure and print CSS.
 */
function wpe_brand_parse_users_brand( array $wpe_brand ) {
	$meta = $wpe_brand['meta'] ?? array();
	if ( empty( $meta ) ) {
		return;
	}
	wpe_brand_print_brand_colors_head( $meta );
}

/** Normalize a HEX color (#RGB or #RRGGBB). */
function wpe_brand_normalize_hex_color( $color ): ?string {
	if ( function_exists( 'sanitize_hex_color' ) ) {
		return sanitize_hex_color( $color ) ?: null;
	}
	$color = trim( (string) $color );
	if ( $color === '' ) return null;
	if ( $color[0] !== '#' ) $color = '#' . $color;
	if ( preg_match( '/^#([A-Fa-f0-9]{3}|[A-Fa-f0-9]{6})$/', $color ) !== 1 ) {
		return null;
	}
	return strtolower( $color );
}

/** Detect Bricks editor contexts to optionally add !important. */
function wpe_brand_is_bricks_editor(): bool {
	if ( function_exists( 'bricks_is_builder' ) && bricks_is_builder() ) {
		return true;
	}
	if ( isset( $_GET['bricks'] ) ) {
		$val = strtolower( (string) wp_unslash( $_GET['bricks'] ) );
		if ( in_array( $val, array( 'run', 'builder', 'preview' ), true ) ) {
			return true;
		}
	}
	return false;
}

/**
 * Build a :root CSS block from Brand color meta.
 *
 * Maps:
 *  - brand_primary_color   -> --brand-primary
 *  - brand_secondary_color -> --brand-secondary
 *  - brand_tertiary_color  -> --brand-tertiary
 *
 * Generates exactly 3 steps for -d-, -l-, and -t- series using color-mix in oklch.
 * Also emits --brand-*-text as either #000000 or #ffffff (higher WCAG contrast).
 * If $important is true, appends !important to each assignment (used in Bricks editor).
 */
function wpe_brand_parse_brand_colors( array $meta, bool $important = false ): string {
	$map = array(
		'brand_primary_color'   => 'primary',
		'brand_secondary_color' => 'secondary',
		'brand_tertiary_color'  => 'tertiary',
	);

	$var_prefix = apply_filters( 'wpe_brand/brand_color_prefix', '--brand-' );
	$steps      = apply_filters( 'wpe_brand/brand_color_steps', array( '95', '50', '5' ) ); // exactly 3 steps
	$imp        = $important ? ' !important' : '';
	$lines      = array();

	foreach ( $map as $meta_key => $slug ) {
		if ( empty( $meta[ $meta_key ] ) ) {
			continue;
		}

		$raw = $meta[ $meta_key ];
		$val = is_array( $raw ) ? reset( $raw ) : $raw; // meta may be array from get_post_meta()
		$hex = wpe_brand_normalize_hex_color( $val );
		if ( ! $hex ) {
			continue;
		}

		$base_var = $var_prefix . $slug;
		$lines[]  = sprintf( '%s: %s%s;', $base_var, $hex, $imp );

		// Decide best text color (#000000 or #ffffff) by contrast ratio
		$text_hex = wpe_brand_best_text_color_for_bg( $hex );
		$lines[]  = sprintf( '%s-text: %s%s;', $base_var, $text_hex, $imp );

		// Derived series (dark, light, transparent)
		$idx = 1;
		foreach ( $steps as $keep ) {
			$keep = preg_replace( '/[^0-9.]/', '', (string) $keep );
			if ( $keep === '' ) {
				continue;
			}
			$lines[] = sprintf(
				'%1$s-d-%2$d: color-mix(in oklch, var(%1$s) %3$s%%, black)%4$s;',
				$base_var, $idx, $keep, $imp
			);
			$lines[] = sprintf(
				'%1$s-l-%2$d: color-mix(in oklch, var(%1$s) %3$s%%, white)%4$s;',
				$base_var, $idx, $keep, $imp
			);
			$lines[] = sprintf(
				'%1$s-t-%2$d: color-mix(in oklch, var(%1$s) %3$s%%, transparent)%4$s;',
				$base_var, $idx, $keep, $imp
			);
			$idx++;
		}
	}

	if ( empty( $lines ) ) return '';
	return ":root{\n  " . implode( "\n  ", $lines ) . "\n}\n";
}

/** Print the :root CSS inside <head> as the last wp_head action. */
function wpe_brand_print_brand_colors_head( array $meta ): void {
	$important = wpe_brand_is_bricks_editor();
	$css       = wpe_brand_parse_brand_colors( $meta, $important );
	if ( $css === '' ) return;

	add_action(
		'wp_head',
		static function () use ( $css ) {
			echo "\n<style id=\"wpe-brand-colors\">\n" . $css . "</style>\n";
		},
		PHP_INT_MAX
	);
}

/** ---------- Contrast helpers (WCAG 2.x relative luminance) ---------- */

/** Expand #rgb or #rrggbb to [r,g,b] 0–255. */
function wpe_brand_hex_to_rgb( string $hex ): ?array {
	$hex = ltrim( strtolower( $hex ), '#' );
	if ( strlen( $hex ) === 3 ) {
		$r = hexdec( str_repeat( $hex[0], 2 ) );
		$g = hexdec( str_repeat( $hex[1], 2 ) );
		$b = hexdec( str_repeat( $hex[2], 2 ) );
		return array( $r, $g, $b );
	}
	if ( strlen( $hex ) === 6 ) {
		$r = hexdec( substr( $hex, 0, 2 ) );
		$g = hexdec( substr( $hex, 2, 2 ) );
		$b = hexdec( substr( $hex, 4, 2 ) );
		return array( $r, $g, $b );
	}
	return null;
}

/** Convert 0–255 sRGB to linear (per WCAG). */
function wpe_brand_srgb_to_linear( float $c ): float {
	$c = $c / 255;
	return ( $c <= 0.03928 ) ? ( $c / 12.92 ) : pow( ( $c + 0.055 ) / 1.055, 2.4 );
}

/** Relative luminance (0..1). */
function wpe_brand_relative_luminance( string $hex ): ?float {
	$rgb = wpe_brand_hex_to_rgb( $hex );
	if ( ! $rgb ) return null;
	list( $r, $g, $b ) = $rgb;
	$R = wpe_brand_srgb_to_linear( $r );
	$G = wpe_brand_srgb_to_linear( $g );
	$B = wpe_brand_srgb_to_linear( $b );
	return 0.2126 * $R + 0.7152 * $G + 0.0722 * $B;
}

/** Contrast ratio between two colors (>=1). */
function wpe_brand_contrast_ratio( string $hex1, string $hex2 ): ?float {
	$L1 = wpe_brand_relative_luminance( $hex1 );
	$L2 = wpe_brand_relative_luminance( $hex2 );
	if ( $L1 === null || $L2 === null ) return null;
	$light = max( $L1, $L2 );
	$dark  = min( $L1, $L2 );
	return ( $light + 0.05 ) / ( $dark + 0.05 );
}

/** Choose #000000 or #ffffff for best contrast on a background color. */
function wpe_brand_best_text_color_for_bg( string $bg_hex ): string {
	$bg_hex  = wpe_brand_normalize_hex_color( $bg_hex ) ?: $bg_hex;
	$black   = '#000000';
	$white   = '#ffffff';
	$c_black = wpe_brand_contrast_ratio( $bg_hex, $black );
	$c_white = wpe_brand_contrast_ratio( $bg_hex, $white );
	// Default to black if equal or any nulls
	if ( $c_white !== null && $c_black !== null ) {
		return ( $c_white > $c_black ) ? $white : $black;
	}
	return $black;
}