<?php
namespace Actirise\Includes\Push;

if ( ! defined( 'ABSPATH' ) ) {
	exit; // Exit if accessed directly
}

use Actirise\Includes\Options;
use Actirise\Includes\Push\PushController;
use Actirise\Includes\Push\PushCapabilityReporter;

/**
 * Self-test of the plugin's own push REST API.
 *
 * Many WordPress hosts disable or block the REST API (security plugins,
 * hardened hosts, reverse proxies). A loopback request to the public `ping`
 * route is the only reliable way to tell whether the Actirise API will be able
 * to reach the receiving endpoints. The verdict is persisted locally and
 * reported to the API so it can gate pushing on `rest_api_enabled` and keep the
 * polling fallback as the safety net when REST is unreachable.
 *
 * Runs on activation and daily via cron.
 *
 * @link       https://actirise.com
 * @since      4.3.0
 * @package    actirise
 * @subpackage actirise/includes/push
 * @author     actirise <wordpress@actirise.com>
 */
final class RestSelfTest {
	/**
	 * Option holding the last self-test verdict (bool).
	 *
	 * @since 4.3.0
	 * @var   string
	 */
	const OPTION_ENABLED = 'rest-api-enabled';

	/**
	 * Option holding the Unix timestamp of the last self-test.
	 *
	 * @since 4.3.0
	 * @var   string
	 */
	const OPTION_LAST_TEST = 'rest-api-last-test';

	/**
	 * Option holding whether the last report reached the API (bool).
	 *
	 * A reachable REST API is only half of push: until the API has been told,
	 * it pushes nothing, so the polling fallback must stay in charge. Kept
	 * separate from OPTION_ENABLED, which records the local probe verdict only.
	 *
	 * @since 4.3.0
	 * @var   string
	 */
	const OPTION_REPORTED = 'rest-api-reported';

	/**
	 * Timeout, in seconds, for the loopback probe.
	 *
	 * @since 4.3.0
	 * @var   int
	 */
	const PROBE_TIMEOUT = 10;

	/**
	 * Run the self-test: probe the loopback ping, persist the verdict locally,
	 * and report the REST state + push URL to the API.
	 *
	 * @since 4.3.0
	 * @return bool Whether the plugin's REST API is reachable.
	 */
	public function run() {
		$base_path = PushController::REST_NAMESPACE . '/' . PushController::REST_BASE;

		$rest_url  = rest_url( $base_path );
		$ping_url  = rest_url( $base_path . '/ping' );
		$reachable = $this->probe( $ping_url );

		Options::update( self::OPTION_ENABLED, $reachable );
		Options::update( self::OPTION_LAST_TEST, time() );

		$reporter = new PushCapabilityReporter();
		$reported = $reporter->report( $reachable, $rest_url );

		// The API only pushes once it has been told; a report that never landed
		// (no token or website uuid yet, gateway or ACL error) must leave the
		// polling fallback on, whatever the probe said.
		Options::update( self::OPTION_REPORTED, $reported );

		return $reachable;
	}

	/**
	 * Whether a loopback GET to the ping URL returns HTTP 200.
	 *
	 * @since 4.3.0
	 * @param string $ping_url Absolute URL of the public ping route.
	 * @return bool
	 */
	private function probe( $ping_url ) {
		$response = wp_remote_get(
			$ping_url,
			array(
				'timeout'   => self::PROBE_TIMEOUT,
				'sslverify' => false,
			)
		);

		if ( is_wp_error( $response ) ) {
			return false;
		}

		return (int) wp_remote_retrieve_response_code( $response ) === 200;
	}
}