<?php

defined( 'ABSPATH' ) || exit;

final class AIEO_Web_Cache_Sync {

	const ACTION = 'aieo_web_cache_sync';

	
	private static $pending = array();

	public static function init() {
		add_action( 'admin_post_nopriv_' . self::ACTION, array( __CLASS__, 'handle' ) );
		add_action( 'admin_post_' . self::ACTION, array( __CLASS__, 'handle' ) );
		if ( 'cli' === PHP_SAPI ) {
			add_action( 'update_option_aieo_dmm_settings', array( __CLASS__, 'settings_changed' ) ); 
			add_action( 'add_option_aieo_dmm_settings', array( __CLASS__, 'settings_changed' ) );
		}
	}

	public static function settings_changed() {
		self::mark( 'settings' );
	}

	
	public static function mark( $what ) {
		if ( 'cli' !== PHP_SAPI || ! (bool) apply_filters( 'aieo_web_cache_sync_needed', wp_using_ext_object_cache() ) ) {
			return; 
		}
		if ( ! self::$pending ) {
			add_action( 'shutdown', array( __CLASS__, 'send' ), 1 );
		}
		self::$pending[ (string) $what ] = true;
	}

	
	private static function signature( $ts, $what ) {
		return hash_hmac( 'sha256', self::ACTION . '|' . $ts . '|' . $what, wp_salt( 'auth' ) );
	}

	
	public static function send() {
		$what          = implode( ',', array_keys( self::$pending ) );
		self::$pending = array();
		if ( '' === $what ) {
			return;
		}
		$ts   = (string) time();
		$url  = admin_url( 'admin-post.php' );
		$host = (string) wp_parse_url( $url, PHP_URL_HOST );
		$port = (int) wp_parse_url( $url, PHP_URL_PORT );
		$port = $port > 0 ? $port : ( 'https' === wp_parse_url( $url, PHP_URL_SCHEME ) ? 443 : 80 );
		$pin  = static function ( $handle ) use ( $host, $port ) {
			curl_setopt( $handle, CURLOPT_RESOLVE, array( $host . ':' . $port . ':127.0.0.1' ) ); 
			return $handle;
		};
		add_filter( 'http_api_curl', $pin );
		$response = wp_remote_post(
			$url,
			array(
				'timeout'   => 5,
				'sslverify' => apply_filters( 'https_local_ssl_verify', false ), 
				'body'      => array(
					'action' => self::ACTION,
					'what'   => $what,
					'ts'     => $ts,
					'sig'    => self::signature( $ts, $what ),
				),
			)
		);
		remove_filter( 'http_api_curl', $pin );
		$answer = is_wp_error( $response ) ? null : json_decode( (string) wp_remote_retrieve_body( $response ), true );
		$done   = is_array( $answer ) && ! empty( $answer['success'] ) ? implode( ',', (array) ( $answer['data']['dropped'] ?? array() ) ) : '';
		if ( defined( 'WP_CLI' ) && WP_CLI ) {
			if ( '' !== $done ) {
				WP_CLI::debug( 'The web server dropped its cached copies: ' . $done . '.', 'aieo' );
			} else {
				WP_CLI::warning( 'Rooster One could not reach the web server to drop its cached copies (' . $what . '); they expire on their own.' );
			}
		}
	}

	
	public static function handle() {
		
		$what = isset( $_POST['what'] ) ? sanitize_text_field( wp_unslash( $_POST['what'] ) ) : '';
		$ts   = isset( $_POST['ts'] ) ? absint( $_POST['ts'] ) : 0;
		$sig  = isset( $_POST['sig'] ) ? sanitize_text_field( wp_unslash( $_POST['sig'] ) ) : '';
		
		if ( abs( time() - $ts ) > 120 || ! hash_equals( self::signature( (string) $ts, $what ), $sig ) ) {
			wp_send_json_error( null, 403 );
		}
		$dropped = array();
		foreach ( explode( ',', $what ) as $part ) {
			if ( 'settings' === $part ) {
				
				wp_cache_delete( 'aieo_dmm_settings', 'options' );
				wp_cache_delete( 'alloptions', 'options' );
				wp_cache_delete( 'notoptions', 'options' );
				if ( class_exists( 'AIEO_DMM_Settings' ) ) {
					AIEO_DMM_Settings::flush_memo();
				}
				$dropped[] = 'settings';
			} elseif ( 'seo' === $part && class_exists( 'AIEO_SEO_Head' ) && function_exists( 'wp_cache_supports' ) && wp_cache_supports( 'flush_group' ) ) {
				wp_cache_flush_group( AIEO_SEO_Head::CACHE_GROUP ); 
				$dropped[] = 'seo';
			}
		}
		wp_send_json_success( array( 'dropped' => $dropped ) );
	}
}

AIEO_Web_Cache_Sync::init();