<?php
/**
 * Plugin Name:       WiloAI
 * Description:       Read and write Rank Math or Yoast SEO metadata through the WordPress REST API and request UpdraftPlus database backups.
 * Version:           1.0
 * Author:            WiloAI
 * Author URI:        https://wiloai.com/
 * License:           GPLv2 or later
 * License URI:       https://www.gnu.org/licenses/gpl-2.0.html
 * Text Domain:       wiloai
 * Requires at least: 6.0
 * Requires PHP:      7.4
 *
 * @package WiloAI
 */

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

/**
 * Resolve the active SEO provider. Rank Math takes precedence.
 *
 * @return array|null REST field to provider meta-key map, or null.
 */
function wiloai_meta_map() {
	if ( defined( 'RANK_MATH_VERSION' ) ) {
		return array(
			'meta_title'       => 'rank_math_title',
			'meta_description' => 'rank_math_description',
			'focus_keyword'    => 'rank_math_focus_keyword',
		);
	}
	if ( defined( 'WPSEO_VERSION' ) ) {
		return array(
			'meta_title'       => '_yoast_wpseo_title',
			'meta_description' => '_yoast_wpseo_metadesc',
			'focus_keyword'    => '_yoast_wpseo_focuskw',
		);
	}
	return null;
}

/** Register unified fields on all REST-enabled post types. */
function wiloai_register_fields() {
	$map = wiloai_meta_map();
	if ( ! $map ) {
		return;
	}
	$args = array(
		'get_callback'    => 'wiloai_get_field',
		'update_callback' => 'wiloai_update_field',
		'schema'          => array(
			'type'    => 'string',
			'context' => array( 'view', 'edit' ),
		),
	);
	foreach ( get_post_types( array( 'show_in_rest' => true ), 'names' ) as $post_type ) {
		foreach ( array_keys( $map ) as $field ) {
			register_rest_field( $post_type, $field, $args );
		}
	}
}
add_action( 'rest_api_init', 'wiloai_register_fields' );

/**
 * Read a field. The focus keyword is private to users who can edit the post.
 *
 * @param array  $prepared_post Prepared post data.
 * @param string $field REST field name.
 * @return string
 */
function wiloai_get_field( $prepared_post, $field ) {
	$map     = wiloai_meta_map();
	$post_id = isset( $prepared_post['id'] ) ? (int) $prepared_post['id'] : 0;
	if ( ! $map || ! $post_id || ! isset( $map[ $field ] ) ) {
		return '';
	}
	if ( 'focus_keyword' === $field && ! current_user_can( 'edit_post', $post_id ) ) {
		return '';
	}
	return (string) get_post_meta( $post_id, $map[ $field ], true );
}

/**
 * Validate and write a field after checking access to this specific post.
 *
 * @param mixed   $value Incoming value.
 * @param WP_Post $post Target post.
 * @param string  $field REST field name.
 * @return true|WP_Error
 */
function wiloai_update_field( $value, $post, $field ) {
	if ( ! current_user_can( 'edit_post', $post->ID ) ) {
		return new WP_Error( 'wiloai_forbidden', __( 'You cannot edit SEO metadata for this post.', 'wiloai' ), array( 'status' => rest_authorization_required_code() ) );
	}
	$map = wiloai_meta_map();
	if ( ! $map || ! isset( $map[ $field ] ) ) {
		return new WP_Error( 'wiloai_unsupported_field', __( 'No supported SEO field is available.', 'wiloai' ), array( 'status' => 400 ) );
	}
	if ( ! is_string( $value ) ) {
		return new WP_Error( 'wiloai_invalid_value', __( 'SEO metadata must be a string.', 'wiloai' ), array( 'status' => 400 ) );
	}
	$value  = 'meta_description' === $field ? sanitize_textarea_field( $value ) : sanitize_text_field( $value );
	$stored = update_post_meta( $post->ID, $map[ $field ], wp_slash( $value ) );
	if ( false === $stored ) {
		// SEO providers may normalize values further (for example Yoast removes line breaks).
		$expected = sanitize_meta( $map[ $field ], $value, 'post', get_post_type( $post ) );
		if ( (string) get_post_meta( $post->ID, $map[ $field ], true ) !== $expected ) {
			return new WP_Error( 'wiloai_write_failed', __( 'SEO metadata could not be saved.', 'wiloai' ), array( 'status' => 500 ) );
		}
	}
	return true;
}

/** Register the administrator-only backup route. */
function wiloai_register_backup_route() {
	register_rest_route(
		'wiloai/v1',
		'/updraft-backup',
		array(
			'methods'             => 'POST',
			'callback'            => 'wiloai_queue_database_backup',
			'permission_callback' => 'wiloai_backup_permission',
		)
	);
}
add_action( 'rest_api_init', 'wiloai_register_backup_route' );

/**
 * Check whether the authenticated user may request a backup.
 *
 * @return bool
 */
function wiloai_backup_permission() {
	return current_user_can( 'manage_options' );
}

/**
 * Release only the lock value owned by this request, not a newer lock.
 *
 * @param int $expires Lock expiry timestamp.
 * @return void
 */
function wiloai_release_backup_lock( $expires ) {
	global $wpdb;
	// Atomic compare-and-delete prevents competing requests removing a newer lock.
	// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Atomic lock operation; option caches are explicitly invalidated below.
	$deleted = $wpdb->delete(
		$wpdb->options,
		array(
			'option_name'  => 'wiloai_backup_lock',
			'option_value' => (string) $expires,
		),
		array( '%s', '%s' )
	);
	if ( $deleted ) {
		wp_cache_delete( 'wiloai_backup_lock', 'options' );
		wp_cache_delete( 'notoptions', 'options' );
	}
}

/**
 * Queue one database backup; a 202 response is not confirmation of completion.
 *
 * @return WP_REST_Response|WP_Error
 */
function wiloai_queue_database_backup() {
	if ( ! has_action( 'updraft_backupnow_backup_database' ) ) {
		return new WP_Error( 'wiloai_updraft_unavailable', __( 'UpdraftPlus database backup support is not active.', 'wiloai' ), array( 'status' => 503 ) );
	}
	if ( wp_next_scheduled( 'wiloai_run_database_backup' ) ) {
		return new WP_Error( 'wiloai_backup_pending', __( 'A database backup is already queued.', 'wiloai' ), array( 'status' => 429 ) );
	}
	$previous = (int) get_option( 'wiloai_backup_lock', 0 );
	if ( $previous && $previous <= time() ) {
		wiloai_release_backup_lock( $previous );
	}
	$expires = time() + 10 * MINUTE_IN_SECONDS;
	if ( ! add_option( 'wiloai_backup_lock', $expires, '', false ) ) {
		return new WP_Error( 'wiloai_backup_rate_limited', __( 'Wait ten minutes between database backup requests.', 'wiloai' ), array( 'status' => 429 ) );
	}
	$scheduled = wp_schedule_single_event( time(), 'wiloai_run_database_backup', array(), true );
	if ( is_wp_error( $scheduled ) || ! $scheduled ) {
		wiloai_release_backup_lock( $expires );
		return new WP_Error( 'wiloai_backup_schedule_failed', __( 'The database backup could not be queued.', 'wiloai' ), array( 'status' => 500 ) );
	}
	return new WP_REST_Response(
		array(
			'status'      => 'queued',
			'backup_type' => 'database',
		),
		202
	);
}

/** Run a queued request using UpdraftPlus's own database-only backup hook. */
function wiloai_run_database_backup() {
	if ( has_action( 'updraft_backupnow_backup_database' ) ) {
		// phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedHooknameFound -- This hook belongs to UpdraftPlus.
		do_action( 'updraft_backupnow_backup_database', array( 'nocloud' => 0 ) );
	}
}
add_action( 'wiloai_run_database_backup', 'wiloai_run_database_backup' );

/** Remove pending requests and the cooldown when WiloAI is deactivated. */
function wiloai_deactivate() {
	wp_clear_scheduled_hook( 'wiloai_run_database_backup' );
	delete_option( 'wiloai_backup_lock' );
}
register_deactivation_hook( __FILE__, 'wiloai_deactivate' );