<?php

namespace Modules\Core\MigrateImport\Services;

use Lunar\Models\Language;

/**
 * The language every resolver in an import run writes product-facing text
 * under (name, description, option names, ...) — NOT necessarily this
 * store's own Lunar\Models\Language::getDefault(). An export file has no
 * reliable way to declare its own language, and a store's default admin/
 * storefront language is an independent fact from whatever language a
 * given export happens to be written in — conflating the two (this
 * class's own former name, DefaultLocale, said as much) used to silently
 * save every imported product's text under the wrong language, invisible
 * unless that language was also the one selected while viewing/editing
 * the product afterward.
 *
 * Set once per import run from the operator's own answer (see
 * Command\MigrateImportCommand::askImportLocale(), threaded through
 * ImportSpec::$locale) at the top of Importer::import() — every resolver
 * downstream (ProductAttributeResolver, ProductOptionResolver,
 * CollectionResolver, ImportAttributeResolver) calls code() exactly as
 * before, unaware anything changed. Falls back to Language::getDefault()
 * only when nothing was ever set (e.g. an import path with no locale
 * concept of its own — JudgeMe's reviews-only export never calls set()).
 */
class ImportLocale
{
    private static ?string $code = null;

    public static function set(string $code): void
    {
        self::$code = $code;
    }

    public static function code(): string
    {
        return self::$code ?? Language::getDefault()->code;
    }

    /**
     * A static property outlives a single request only inside a
     * long-running worker process, where a queued job for one import
     * must not leak its locale into the next — called at the end of
     * every Importer::import() run, success or failure.
     */
    public static function reset(): void
    {
        self::$code = null;
    }
}