<?php

if ( ! defined( 'ABSPATH' ) ) {
    exit();
}

/**
 * One-time copy of data stored under the previous "trp_" prefix to the "translangated_" names.
 *
 * Sites that ran an earlier Translangated build, or that come from TranslatePress (which uses the same
 * storage layout), keep their settings and translations. The old options, tables and meta are copied,
 * never moved or deleted, so the previous plugin keeps working if it is reactivated.
 *
 * Runs once per site, before the plugin reads any setting.
 */
class Translangated_Prefix_Migration {

    const DONE_OPTION = 'translangated_prefix_migration';
    const OLD         = 'trp_';
    const NEW_PREFIX  = 'translangated_';

    public static function maybe_run() {
        if ( get_option( self::DONE_OPTION ) ) {
            return;
        }
        // Nothing to copy (fresh install), or already set up under the new names.
        if ( false === get_option( self::OLD . 'settings' ) || false !== get_option( self::NEW_PREFIX . 'settings' ) ) {
            update_option( self::DONE_OPTION, 'not-needed' );
            return;
        }

        self::copy_options();
        self::copy_tables();
        self::copy_meta();
        self::clear_old_cron_events();

        update_option( self::DONE_OPTION, 'copied' );
    }

    private static function new_name( $old_name, $old_prefix, $new_prefix ) {
        return $new_prefix . substr( $old_name, strlen( $old_prefix ) );
    }

    private static function copy_options() {
        global $wpdb;
        $rows = $wpdb->get_results( $wpdb->prepare( 'SELECT option_name, option_value, autoload FROM %i WHERE option_name LIKE %s', $wpdb->options, $wpdb->esc_like( self::OLD ) . '%' ) ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- one-time migration
        foreach ( (array) $rows as $row ) {
            $new = self::new_name( $row->option_name, self::OLD, self::NEW_PREFIX );
            // Copy the stored (serialized) value as is.
            $wpdb->query( $wpdb->prepare( 'INSERT IGNORE INTO %i (option_name, option_value, autoload) VALUES (%s, %s, %s)', $wpdb->options, $new, $row->option_value, $row->autoload ) ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- one-time migration
        }
        wp_cache_delete( 'alloptions', 'options' );
        wp_cache_delete( 'notoptions', 'options' );
    }

    private static function copy_tables() {
        global $wpdb;
        $old_prefix = $wpdb->prefix . self::OLD;
        $tables     = $wpdb->get_col( $wpdb->prepare( 'SHOW TABLES LIKE %s', $wpdb->esc_like( $old_prefix ) . '%' ) ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- one-time migration
        foreach ( (array) $tables as $old_table ) {
            $new_table = self::new_name( $old_table, $old_prefix, $wpdb->prefix . self::NEW_PREFIX );
            if ( $wpdb->get_var( $wpdb->prepare( 'SHOW TABLES LIKE %s', $wpdb->esc_like( $new_table ) ) ) ) { // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- one-time migration
                continue;
            }
            $wpdb->query( $wpdb->prepare( 'CREATE TABLE %i LIKE %i', $new_table, $old_table ) ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching, WordPress.DB.DirectDatabaseQuery.SchemaChange -- one-time migration
            $wpdb->query( $wpdb->prepare( 'INSERT INTO %i SELECT * FROM %i', $new_table, $old_table ) ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- one-time migration
        }
    }

    private static function copy_meta() {
        global $wpdb;
        $meta_tables = array(
            array( $wpdb->postmeta, 'post_id' ),
            array( $wpdb->termmeta, 'term_id' ),
            array( $wpdb->usermeta, 'user_id' ),
        );
        foreach ( $meta_tables as $meta ) {
            list( $table, $object_column ) = $meta;
            foreach ( array( '_' . self::OLD => '_' . self::NEW_PREFIX, self::OLD => self::NEW_PREFIX ) as $old_key_prefix => $new_key_prefix ) {
                $wpdb->query( $wpdb->prepare( // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- one-time migration
                    'INSERT INTO %i (%i, meta_key, meta_value) SELECT %i, CONCAT(%s, SUBSTRING(meta_key, %d)), meta_value FROM %i WHERE meta_key LIKE %s',
                    $table, $object_column, $object_column, $new_key_prefix, strlen( $old_key_prefix ) + 1, $table, $wpdb->esc_like( $old_key_prefix ) . '%'
                ) );
            }
        }
        // Dismissed-notice flags are stored as "{notice id}_dismiss_notification" user meta; ids start with the prefix.
        wp_cache_flush_group( 'post_meta' );
        wp_cache_flush_group( 'term_meta' );
        wp_cache_flush_group( 'user_meta' );
    }

    private static function clear_old_cron_events() {
        foreach ( (array) _get_cron_array() as $events ) {
            foreach ( array_keys( (array) $events ) as $hook ) {
                if ( strpos( $hook, self::OLD ) === 0 ) {
                    wp_clear_scheduled_hook( $hook );
                }
            }
        }
    }
}