<?php

namespace AIBP;

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

/**
 * Registers and runs the plugin cron event.
 */
class Scheduler {
	const CRON_HOOK = 'aibp_sync_event';
	const REST_NAMESPACE = 'aibp/v1';
	const REST_ROUTE = '/sync';

	/**
	 * @var Settings
	 */
	private $settings;

	/**
	 * @var Sync_Service
	 */
	private $sync_service;

	/**
	 * @param Settings     $settings Plugin settings service.
	 * @param Sync_Service $sync_service Shared sync service.
	 */
	public function __construct( Settings $settings, Sync_Service $sync_service ) {
		$this->settings     = $settings;
		$this->sync_service = $sync_service;

		add_filter( 'cron_schedules', array( $this, 'add_schedule' ) );
		add_action( self::CRON_HOOK, array( $this, 'run_sync' ) );
		add_action( 'rest_api_init', array( $this, 'register_rest_routes' ) );
	}

	/**
	 * Adds the custom sync interval based on plugin settings.
	 *
	 * @param array<string, array<string, mixed>> $schedules Existing schedules.
	 * @return array<string, array<string, mixed>>
	 */
	public function add_schedule( $schedules ) {
		$minutes = max( 5, absint( $this->settings->get( 'sync_frequency', 30 ) ) );

		$schedules['aibp_custom_interval'] = array(
			'interval' => $minutes * MINUTE_IN_SECONDS,
			'display'  => sprintf(
				/* translators: %d: number of minutes */
				__( 'Every %d minutes (AI Blog Poster)', 'ai-blog-poster' ),
				$minutes
			),
		);

		return $schedules;
	}

	/**
	 * Re-registers the plugin cron event using the latest interval.
	 */
	public function register_schedule() {
		$this->clear_schedule();

		if ( ! $this->is_wp_cron_enabled() ) {
			return;
		}

		if ( ! wp_next_scheduled( self::CRON_HOOK ) ) {
			wp_schedule_event( time() + MINUTE_IN_SECONDS, 'aibp_custom_interval', self::CRON_HOOK );
		}
	}

	/**
	 * Removes all scheduled plugin cron events.
	 */
	public function clear_schedule() {
		$timestamp = wp_next_scheduled( self::CRON_HOOK );

		while ( $timestamp ) {
			wp_unschedule_event( $timestamp, self::CRON_HOOK );
			$timestamp = wp_next_scheduled( self::CRON_HOOK );
		}
	}

	/**
	 * Runs the shared sync routine for cron.
	 */
	public function run_sync() {
		$this->sync_service->sync( 'wp_cron' );
	}

	/**
	 * Registers a token-protected REST route for server cron usage.
	 */
	public function register_rest_routes() {
		register_rest_route(
			self::REST_NAMESPACE,
			self::REST_ROUTE,
			array(
				'methods'             => 'GET',
				'callback'            => array( $this, 'handle_manual_cron_request' ),
				'permission_callback' => array( $this, 'can_run_manual_cron_request' ),
			)
		);
	}

	/**
	 * Validates the token sent to the manual cron endpoint.
	 *
	 * @param \WP_REST_Request $request Incoming request.
	 * @return bool
	 */
	public function can_run_manual_cron_request( \WP_REST_Request $request ) {
		$token = (string) $request->get_param( 'token' );

		return ! empty( $token ) && hash_equals( (string) $this->settings->get( 'cron_token', '' ), $token );
	}

	/**
	 * Executes sync from the manual cron REST endpoint.
	 *
	 * @param \WP_REST_Request $request Incoming request.
	 * @return \WP_REST_Response
	 */
	public function handle_manual_cron_request( \WP_REST_Request $request ) {
		$result = $this->sync_service->sync( 'manual_cron' );

		if ( is_wp_error( $result ) ) {
			return new \WP_REST_Response(
				array(
					'success' => false,
					'message' => $result->get_error_message(),
				),
				500
			);
		}

		return new \WP_REST_Response(
			array(
				'success' => true,
				'result'  => $result,
			),
			200
		);
	}

	/**
	 * Returns whether WP-Cron scheduling is enabled in plugin settings.
	 *
	 * @return bool
	 */
	public function is_wp_cron_enabled() {
		return 'wp_cron' === $this->settings->get( 'sync_mode', 'wp_cron' );
	}

	/**
	 * Returns the full manual cron URL with token.
	 *
	 * @return string
	 */
	public function get_manual_cron_url() {
		$url = add_query_arg(
			array(
				'token' => (string) $this->settings->get( 'cron_token', '' ),
			),
			rest_url( self::REST_NAMESPACE . self::REST_ROUTE )
		);

		// Keep the REST route readable when WordPress uses the plain permalink fallback.
		return str_replace( array( '%2F', '%2f' ), '/', $url );
	}
}