<?php

namespace Modules\Core\Privacy\Jobs;

use Throwable;
use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Foundation\Bus\Dispatchable;
use Illuminate\Queue\InteractsWithQueue;
use Illuminate\Queue\SerializesModels;
use Illuminate\Support\Facades\Event;
use Illuminate\Support\Facades\Log;
use Modules\Core\Privacy\Contracts\PersonalDataProvider;
use Modules\Core\Privacy\DTOs\CustomerSubject;
use Modules\Core\Privacy\Events\PersonalDataGathered;
use Modules\Core\Privacy\DTOs\ExportReport;
use Modules\Core\Privacy\DTOs\ProviderExportResult;
use Modules\Core\Privacy\Enums\ExportRequestStatus;
use Modules\Core\Privacy\Models\DataExportRequest;
use Modules\Core\Privacy\Services\PrivacyManager;
use Modules\Core\Privacy\DTOs\UserSubject;

/**
 * Gathers every registered PersonalDataProvider's export data for one request, all
 * sequentially in this single job — deliberately not fanned out into one job per
 * provider. Per-subject export work is small (a handful of indexed queries per
 * provider), so there's no real parallelism win, and one job means "finished" is
 * just "handle() returned," with no Bus::batch()/completion-counting needed. If a
 * future provider ever does something genuinely slow (an external API call, a
 * generated PDF), that's the point to reconsider — not before.
 *
 * Calls each provider's *ForCustomer() or *ForUser() method depending on the
 * request's polymorphic subject — see Modules\Core\Privacy\Services\PrivacyService and
 * docs/privacy.md "User-scope vs Customer-scope".
 *
 * Writing the gathered data to a file is intentionally NOT done here — see
 * PersonalDataGathered and Modules\Core\Privacy\Listeners\WriteExportToCsvListener,
 * which keeps the export *format* swappable without touching how data is gathered.
 */
class ExportDataSubjectJob implements ShouldQueue
{
    use Dispatchable;
    use InteractsWithQueue;
    use Queueable;
    use SerializesModels;

    public function __construct(
        public readonly DataExportRequest $request,
    ) {}

    public function handle(PrivacyManager $manager): void
    {
        if ($this->request->isForCustomer()) {
            $subject = new CustomerSubject(customerId: $this->request->subject_id);
            $results = array_map(
                fn (PersonalDataProvider $provider) => $this->safeExport($provider, 'exportForCustomer', $subject),
                $manager->providers()
            );
        } else {
            $subject = new UserSubject(userId: $this->request->subject_id, email: $this->request->email);
            $results = array_map(
                fn (PersonalDataProvider $provider) => $this->safeExport($provider, 'exportForUser', $subject),
                $manager->providers()
            );
        }

        Event::dispatch(new PersonalDataGathered(
            $this->request,
            new ExportReport($subject, $results)
        ));
    }

    public function failed(Throwable $exception): void
    {
        $this->request->update(['status' => ExportRequestStatus::Failed]);
    }

    /**
     * Catches per-provider so one provider throwing doesn't discard every
     * other provider's already-gathered export data for this same request —
     * without this, the whole array_map aborts, handle() never reaches
     * Event::dispatch(), and failed() marks the ENTIRE request Failed even
     * though most providers may have already gathered their data
     * successfully. Logged via Log::error() so a thrown provider is still
     * visible to staff, not just an empty/missing section in the export.
     *
     * @param  'exportForCustomer'|'exportForUser'  $method
     */
    private function safeExport(PersonalDataProvider $provider, string $method, CustomerSubject|UserSubject $subject): ProviderExportResult
    {
        try {
            return $provider->{$method}($subject);
        } catch (Throwable $e) {
            Log::error("Privacy provider {$provider->name()}::{$method}() threw during export", [
                'provider' => $provider->name(),
                'exception' => $e,
            ]);

            return new ProviderExportResult($provider->name(), [], $e->getMessage());
        }
    }
}