<?php
/**
 * Tier: keep-styles (also runs for all/nuclear).
 *
 * @package Zero_Blocks_Given
 *
 * Removes the WC Product Filter block's own pattern scanner
 * (ProductFilterAttribute::register_block_patterns on wp_loaded) — the single
 * most expensive block-pattern registration on a layered-nav store that never
 * uses the Product Filter block. Unlike the `all` tier, this leaves the WP
 * global-styles pipeline (theme.json / wp--preset inline styles) AND core
 * block rendering untouched, so the frontend stays pixel-perfect.
 *
 * Front-only: the editor's pattern inserter is left intact.
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Register the keep-styles tier.
 *
 * WC registers ProductFilterAttribute::register_block_patterns as an instance
 * method callback on `wp_loaded` (priority 10). Its class is not reliably
 * reachable through the Blocks DI container, so we match it on the live hook:
 * scan `wp_loaded` callbacks for an object method named `register_block_patterns`
 * whose class basename is `ProductFilterAttribute`, then remove it via the
 * canonical remove_action() API. We hook at priority 0 so the removal lands
 * before the priority-10 registration fires.
 *
 * @return void
 */
function zeroblg_register_tier_keep_styles(): void {
	add_action(
		'wp_loaded',
		static function (): void {
			// Front-only: leave the block editor's pattern registration intact.
			if ( is_admin() ) {
				return;
			}

			global $wp_filter;

			if ( empty( $wp_filter['wp_loaded'] ) || empty( $wp_filter['wp_loaded']->callbacks ) ) {
				return;
			}

			try {
				$to_remove = array();

				foreach ( $wp_filter['wp_loaded']->callbacks as $priority => $callbacks ) {
					foreach ( $callbacks as $cb ) {
						$fn = isset( $cb['function'] ) ? $cb['function'] : null;

						if ( ! is_array( $fn ) || ! isset( $fn[0], $fn[1] ) || ! is_object( $fn[0] ) ) {
							continue;
						}

						if ( 'register_block_patterns' !== $fn[1] ) {
							continue;
						}

						$basename = basename( str_replace( '\\', '/', get_class( $fn[0] ) ) );

						if ( 'ProductFilterAttribute' === $basename ) {
							// Collect first — removing inside the loop mutates ->callbacks.
							$to_remove[] = array( $fn, (int) $priority );
						}
					}
				}

				foreach ( $to_remove as $entry ) {
					remove_action( 'wp_loaded', $entry[0], $entry[1] );
				}
			} catch ( \Throwable $e ) {
				unset( $e ); // Hook shape changed on this WC version — safe to ignore.
			}
		},
		0
	);
}