<?php
/**
 * Audit check: is a page cache active?
 *
 * @package AIBlackout
 */

namespace AIBlackout\Audit\Checks;

use AIBlackout\Audit\Check;
use AIBlackout\Audit\PageCache;
use AIBlackout\Audit\Result;
use AIBlackout\Enforcement\Htaccess;
use AIBlackout\Enforcement\ServerProfile;

defined( 'ABSPATH' ) || exit;

/**
 * Reports the page cache, and what it means for local blocking.
 *
 * @since 1.0.0
 */
class PageCacheCheck implements Check {

	/**
	 * Page cache detector.
	 *
	 * @var PageCache
	 */
	private $cache;

	/**
	 * Server profile.
	 *
	 * @var ServerProfile
	 */
	private $server;

	/**
	 * The .htaccess layer.
	 *
	 * @var Htaccess
	 */
	private $htaccess;

	/**
	 * Constructor.
	 *
	 * @param PageCache     $cache    Page cache detector.
	 * @param ServerProfile $server   Server profile.
	 * @param Htaccess      $htaccess The .htaccess layer.
	 */
	public function __construct( PageCache $cache, ServerProfile $server, Htaccess $htaccess ) {
		$this->cache    = $cache;
		$this->server   = $server;
		$this->htaccess = $htaccess;
	}

	/**
	 * Returns the check identifier.
	 *
	 * @return string Identifier.
	 */
	public function get_id(): string {
		return 'page_cache';
	}

	/**
	 * Whether a loopback request is required.
	 *
	 * @return bool False.
	 */
	public function needs_loopback(): bool {
		return false;
	}

	/**
	 * Runs the check.
	 *
	 * @return Result The finding.
	 */
	public function run(): Result {
		$label   = __( 'Page caching', 'ai-blackout' );
		$plugins = $this->cache->get_active_plugins();
		$covered = $this->htaccess->is_applied();

		$detail = array(
			'operating'      => $this->cache->is_operating(),
			'drop_in'        => $this->cache->has_drop_in(),
			'plugins'        => array_values( $plugins ),
			'evidence'       => $this->cache->get_evidence(),
			'server_covered' => $covered,
		);

		if ( $this->cache->is_operating() ) {
			return new Result(
				$this->get_id(),
				$label,
				$covered ? Result::INFO : Result::INERT,
				! empty( $plugins )
					? sprintf(
						/* translators: %s: Comma-separated plugin names. */
						__( 'A page cache is running (%s).', 'ai-blackout' ),
						implode( ', ', $plugins )
					)
					: __( 'A page cache is running.', 'ai-blackout' ),
				$covered
					? __( 'Visitors are often served without WordPress running. Your server-level rules block AI crawlers before that happens, so caching does not weaken your protection.', 'ai-blackout' )
					: __( 'Visitors are often served without WordPress running, which means WordPress-level blocking is skipped for those requests. AI crawlers hitting a cached page are not being refused.', 'ai-blackout' ),
				$covered
					? ''
					: ( $this->server->supports_htaccess()
						? __( 'Server rules run before the cache and would close this gap. See the .htaccess layer for why they are not in place.', 'ai-blackout' )
						: __( 'Add the nginx rule to your server configuration, or ask your host to add it.', 'ai-blackout' ) ),
				$detail
			);
		}

		if ( $this->cache->is_installed_but_dormant() ) {
			return new Result(
				$this->get_id(),
				$label,
				Result::INFO,
				$this->cache->describe_dormancy(),
				__( 'Because pages are not being cached, requests are reaching WordPress and WordPress-level blocking is working. If you switch to a host or setup where this cache starts working, check this screen again.', 'ai-blackout' ),
				'',
				$detail
			);
		}

		return new Result(
			$this->get_id(),
			$label,
			Result::INFO,
			__( 'No page cache was found inside WordPress.', 'ai-blackout' ),
			__( 'Requests appear to be reaching WordPress, so WordPress-level blocking should be working. Caching run by your host or a CDN is invisible from inside WordPress, so this is not a guarantee. The self-test can confirm what visitors actually receive.', 'ai-blackout' ),
			'',
			$detail
		);
	}
}