<?php
/**
 * TMDO_Array_Literal_Repair — finds flat text / textarea values stored as the
 * literal "Array" (pre-1.1.0 type caster cast arrays with (string)) and
 * rewrites them from native meta.
 *
 * Native rows that are themselves "Array" (written back by an earlier
 * bridge-restore-native) cannot be repaired here: they are only listed, to be
 * restored from a backup.
 *
 * @package WP_Data_Optimizer
 */

declare(strict_types=1);

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

// phpcs:disable WordPress.DB.PreparedSQL.InterpolatedNotPrepared,WordPress.DB.DirectDatabaseQuery -- table / column names come from the registry and adapter; values are prepared.

/**
 * Repairs "Array" literals in flat text / textarea columns.
 */
final class TMDO_Array_Literal_Repair {

	/** What (string) array produced. */
	private const LITERAL = 'Array';

	/**
	 * Scan (and optionally repair) one entity type.
	 *
	 * @param string $entity_type Entity type.
	 * @param bool   $apply       Write repairs; false = report only.
	 * @return array{found:int, repairable:int, repaired:int, unrepairable:array<int, array{group:string, key:string, id:int, reason:string}>, native_polluted:array<int, array{group:string, key:string, id:int}>}
	 */
	public static function run( string $entity_type, bool $apply ): array {
		global $wpdb;

		$report = array(
			'found'           => 0,
			'repairable'      => 0,
			'repaired'        => 0,
			'unrepairable'    => array(),
			'native_polluted' => array(),
		);

		$adapter = TMDO_Entity_Registry::get_adapter( $entity_type );
		if ( ! $adapter ) {
			return $report;
		}
		$meta_table = $adapter->get_native_meta_table();
		$id_col     = $adapter->get_entity_id_column();
		$meta_pk    = 'user' === $entity_type ? 'umeta_id' : 'meta_id';

		foreach ( TMDO_Entity_Registry::get_groups_for_type( $entity_type ) as $group ) {
			$table = TMDO_Schema_Manager::get_table_name( $entity_type, $group );
			if ( ! TMDO_Schema_Manager::table_exists( $table ) ) {
				continue;
			}

			foreach ( TMDO_Entity_Registry::get_group_fields( $entity_type, $group ) as $field ) {
				if ( ! in_array( $field['type'] ?? 'text', array( 'text', 'textarea' ), true ) ) {
					continue;
				}
				$key = (string) $field['key'];
				$col = TMDO_Schema_Manager::sanitize_column_name( $key );

				$ids = $wpdb->get_col( $wpdb->prepare( "SELECT `{$id_col}` FROM `{$table}` WHERE `{$col}` = %s", self::LITERAL ) );
				foreach ( $ids as $id ) {
					$id = (int) $id;
					++$report['found'];

					$native = $wpdb->get_var( $wpdb->prepare( "SELECT meta_value FROM `{$meta_table}` WHERE `{$id_col}` = %d AND meta_key = %s ORDER BY `{$meta_pk}` LIMIT 1", $id, $key ) );
					$reason = null === $native ? 'no_native_row' : ( self::LITERAL === $native ? 'native_is_array_literal' : '' );
					if ( '' !== $reason ) {
						$report['unrepairable'][] = array(
							'group'  => $group,
							'key'    => $key,
							'id'     => $id,
							'reason' => $reason,
						);
						continue;
					}

					++$report['repairable'];
					if ( $apply ) {
						$value = TMDO_Type_Caster::to_db( TMDO_Safe_Unserialize::run( $native ), $field + array( 'group' => $group ) );
						$wpdb->update( $table, array( $col => $value ), array( $id_col => $id ) );
						++$report['repaired'];
					}
				}

				$polluted = $wpdb->get_col( $wpdb->prepare( "SELECT DISTINCT `{$id_col}` FROM `{$meta_table}` WHERE meta_key = %s AND meta_value = %s", $key, self::LITERAL ) );
				foreach ( $polluted as $id ) {
					$report['native_polluted'][] = array(
						'group' => $group,
						'key'   => $key,
						'id'    => (int) $id,
					);
				}
			}
		}

		if ( $report['repaired'] > 0 ) {
			TMDO_Cache_Orchestrator::flush_entity( $entity_type );
		}

		return $report;
	}
}