<?php

namespace App\Http\Controllers;

use App\Enums\ActivityType;
use App\Enums\EmailNotificationType;
use App\Models\User;
use App\Services\ActivityLog;
use Illuminate\Http\RedirectResponse;
use Illuminate\Http\Request;
use Illuminate\Http\Response;
use Illuminate\Support\Facades\URL;
use Illuminate\View\View;

/**
 * One-Click-Abmeldung von Benachrichtigungs-Mails, ohne Login.
 *
 * Die Links in den Mail-Footern sind signiert und ohne Ablauf (Links aus
 * alten Mails bleiben gültig). Der GET-Aufruf trägt den Empfänger direkt
 * aus und zeigt die Bestätigungsseite mit der Möglichkeit, die Abmeldung
 * rückgängig zu machen. Der POST auf dieselbe URL bedient den
 * List-Unsubscribe-Header (RFC 8058) — Mail-Clients senden ihn ohne
 * Nutzer-Interaktion auf der Seite.
 *
 * Jede tatsächliche Zustandsänderung landet im Aktivitäts-Verlauf
 * (Admin ▸ Reports ▸ Verlauf) — wiederholte Klicks erzeugen keine
 * Doppel-Einträge.
 */
class EmailUnsubscribeController extends Controller
{
    public function __construct(private readonly ActivityLog $activityLog) {}

    public function show(Request $request, User $user, string $type): View
    {
        $notificationType = $this->resolveType($type);

        if (! $request->hasValidSignature()) {
            return view('web.email-unsubscribe', [
                'state' => 'invalid',
                'notificationType' => $notificationType,
            ]);
        }

        $this->optOut($user, $notificationType, 'link');

        return view('web.email-unsubscribe', [
            'state' => 'unsubscribed',
            'notificationType' => $notificationType,
            'resubscribeUrl' => URL::signedRoute('email-preferences.resubscribe', [
                'user' => $user->id,
                'type' => $notificationType->value,
            ]),
        ]);
    }

    /**
     * RFC-8058-Endpunkt: Mail-Clients senden `List-Unsubscribe=One-Click`
     * per POST, ohne die Seite zu öffnen. Antwort bewusst schlicht (2xx).
     */
    public function oneClickUnsubscribe(Request $request, User $user, string $type): Response
    {
        abort_unless($request->hasValidSignature(), 403);

        $this->optOut($user, $this->resolveType($type), 'one-click');

        return response('Sie wurden erfolgreich abgemeldet.');
    }

    public function resubscribe(Request $request, User $user, string $type): View|RedirectResponse
    {
        abort_unless($request->hasValidSignature(), 403);

        $notificationType = $this->resolveType($type);

        if (! $user->wantsEmailNotification($notificationType)) {
            $user->optIntoEmailNotification($notificationType);

            $this->activityLog->record(
                ActivityType::EmailUnsubscribe,
                sprintf('%s (%s) hat %s wieder aktiviert.', $user->name, $user->email, $notificationType->unsubscribeLabel()),
                user: $user,
                meta: ['type' => $notificationType->value, 'action' => 'resubscribe'],
            );
        }

        return view('web.email-unsubscribe', [
            'state' => 'resubscribed',
            'notificationType' => $notificationType,
        ]);
    }

    private function optOut(User $user, EmailNotificationType $notificationType, string $method): void
    {
        if (! $user->wantsEmailNotification($notificationType)) {
            return;
        }

        $user->optOutOfEmailNotification($notificationType);

        $this->activityLog->record(
            ActivityType::EmailUnsubscribe,
            sprintf('%s (%s) hat %s abbestellt.', $user->name, $user->email, $notificationType->unsubscribeLabel()),
            user: $user,
            meta: ['type' => $notificationType->value, 'action' => 'unsubscribe', 'method' => $method],
        );
    }

    private function resolveType(string $type): EmailNotificationType
    {
        $notificationType = EmailNotificationType::tryFrom($type);

        abort_if($notificationType === null, 404);

        return $notificationType;
    }
}