app/Domains/Admin/Actions/RemovePaymentMethodUsage/RemovePaymentMethodUsageAction.php

@@ -11,7 +11,7 @@ class RemovePaymentMethodUsageAction
     public function execute(AvailablePaymentMethod $availablePaymentMethod): void
     {
         foreach ($availablePaymentMethod->events()->get() as $event) {
-            $event->paymentMethods()->detach($availablePaymentMethod->id);
+            $event->paymentMethods()->detach($availablePaymentMethod->slug);
 
             $remainingActive = $event->paymentMethods()->where('active', true)->count();
             if ($remainingActive === 0 && $event->registration_allowed) {

app/Domains/Event/Actions/CreateEvent/CreateEventCommand.php

@@ -63,7 +63,7 @@ class CreateEventCommand {
             foreach (AvailablePaymentMethod::where('active', true)->get() as $availablePaymentMethod) {
                 EventPaymentMethods::create([
                     'event_id' => $event->id,
-                    'available_payment_method_id' => $availablePaymentMethod->id,
+                    'slug' => $availablePaymentMethod->slug,
                 ]);
             }
 

app/Domains/Event/Actions/SignUp/SignUpCommand.php

@@ -21,7 +21,6 @@ class SignUpCommand {
         };
 
         $participantAge = new Age($this->request->birthday);
-        $paymentMethod = $this->request->event->paymentMethods()->where('active', true)->first();
 
         $response->participant = $this->request->event->participants()->create(
             [
@@ -62,7 +61,7 @@ class SignUpCommand {
                 'notes' => $this->request->notes,
                 'amount' => $this->request->amount,
                 'payment_purpose' => $this->request->event->name . ' - Beitrag ' . $this->request->firstname . ' ' . $this->request->lastname,
-                'payment_method' => $paymentMethod?->slug, // available_payment_methods.slug === payment_methods.slug
+                'payment_method' => $this->request->paymentMethod,
                 'efz_status' => $participantAge->isfullAged() ? EfzStatus::EFZ_STATUS_NOT_CHECKED : EfzStatus::EFZ_STATUS_NOT_REQUIRED,
             ]
         );

app/Domains/Event/Actions/SignUp/SignUpRequest.php

@@ -44,7 +44,8 @@ class SignUpRequest {
         public int $arrival_eating,
         public int $departure_eating,
         public ?string $notes,
-        public Amount $amount
+        public Amount $amount,
+        public ?string $paymentMethod,
     ) {
     }
 }

app/Domains/Event/Controllers/SignupController.php

@@ -24,7 +24,12 @@ class SignupController extends CommonController {
             $availableEvents[] = $event->toResource()->toArray($request);
         };
 
-        $event = $this->events->getByIdentifier($eventId, false)?->toResource()->toArray($request);
+        $eventModel = $this->events->getByIdentifier($eventId, false);
+        $event = $eventModel?->toResource()->toArray($request);
+        // Aktuell ist genau eine aktive Zahlungsmethode je Event vorgesehen; wird bereits beim Start
+        // der Anmeldung ermittelt und ans Frontend durchgereicht, statt erst bei der Erstellung des
+        // Teilnehmenden (siehe SignUpCommand).
+        $paymentMethod = $eventModel?->paymentMethods()->where('active', true)->first();
 
         $participantData = [
             'firstname' => '',
@@ -62,6 +67,7 @@ class SignupController extends CommonController {
             'availableEvents' => $availableEvents,
             'localGroups' => $event['contributingLocalGroups'],
             'participantData' => $participantData,
+            'paymentMethod' => $paymentMethod?->slug,
         ]);
         return $inertiaProvider->render();
     }
@@ -136,7 +142,8 @@ class SignupController extends CommonController {
             $registrationData['anreise_essen'],
             $registrationData['abreise_essen'],
             $registrationData['anmerkungen'],
-            $amount
+            $amount,
+            $registrationData['paymentMethod'] ?? null,
         );
 
         $signupCommand = new SignUpCommand($signupRequest);

app/Domains/Event/Views/Partials/CommonSettings.vue

@@ -48,7 +48,7 @@
 
         contributingLocalGroups.value = props.event.contributingLocalGroups?.map(t => t.id) ?? []
         eatingHabits.value = props.event.eatingHabits?.map(t => t.id) ?? []
-        paymentMethods.value = props.event.paymentMethods?.map(t => t.id) ?? []
+        paymentMethods.value = props.event.paymentMethods?.map(t => t.slug) ?? []
     });
 
     async function save() {
@@ -218,7 +218,7 @@
 
                     <tr v-for="paymentMethod in  dynmicProps.paymentMethods">
                         <td>
-                            <input type="checkbox" :id="'paymentmethod' + paymentMethod.id" :value="paymentMethod.id" v-model="paymentMethods" />
+                            <input type="checkbox" :id="'paymentmethod' + paymentMethod.id" :value="paymentMethod.slug" v-model="paymentMethods" />
                             <label style="padding-left: 5px;" :for="'paymentmethod' + paymentMethod.id">{{paymentMethod.name}}</label>
                         </td>
                     </tr>

app/Domains/Event/Views/Partials/SignUpForm/SignupForm.vue

@@ -16,6 +16,7 @@ const props = defineProps({
     event: Object,
     participantData: Object,
     localGroups: Array,
+    paymentMethod: String,
 })
 
 const emit = defineEmits(['registrationDone'])
@@ -23,7 +24,7 @@ const emit = defineEmits(['registrationDone'])
 const {
     currentStep, goToStep, formData, selectedAddons,
     submit, submitting, submitResult, summaryLoading, summaryAmount
-} = useSignupForm(props.event, props.participantData)
+} = useSignupForm(props.event, props.participantData, props.paymentMethod)
 
 const steps = [
     { step: 1, label: 'Alter' },

app/Domains/Event/Views/Partials/SignUpForm/composables/useSignupForm.js

@@ -1,7 +1,7 @@
 import { ref, reactive, computed } from 'vue'
 import axios from 'axios'
 
-export function useSignupForm(event, participantData) {
+export function useSignupForm(event, participantData, paymentMethod) {
     const currentStep = ref(1)
     const submitting = ref(false)
     const summaryLoading = ref(false)
@@ -11,6 +11,7 @@ export function useSignupForm(event, participantData) {
 
     const formData = reactive({
         eatingHabit: 'EATING_HABIT_VEGAN',
+        paymentMethod: paymentMethod ?? null,
         userId: participantData.id,
         eventId: event.id,
         vorname: participantData.firstname ?? '',

app/Domains/Event/Views/Signup.vue

@@ -12,6 +12,7 @@ const props = defineProps({
     availableEvents: Array,
     participantData: Object,
     localGroups: Array,
+    paymentMethod: String,
 })
 
 const showSignup = ref(true)
@@ -103,6 +104,7 @@ function close() {
                     :event="props.event"
                     :participantData="props.participantData ?? {}"
                     :localGroups="props.localGroups ?? []"
+                    :paymentMethod="props.paymentMethod ?? null"
                 />
                 <p v-else class="signup-closed-notice">
                     Die Anmeldung für diese Veranstaltung ist geschlossen.

app/Models/AvailablePaymentMethod.php

@@ -37,6 +37,8 @@ class AvailablePaymentMethod extends InstancedModel
 
     public function events(): BelongsToMany
     {
-        return $this->belongsToMany(Event::class, 'event_payment_methods')->withTimestamps();
+        // Pivot verknüpft über den Slug -- Event::paymentMethods() greift daher automatisch nur
+        // auf Events des aktuell gebundenen Tenants zu (SiteScope auf Event + AvailablePaymentMethod).
+        return $this->belongsToMany(Event::class, 'event_payment_methods', 'slug', 'event_id', 'slug', 'id')->withTimestamps();
     }
 }

app/Models/Event.php

@@ -154,7 +154,10 @@ class Event extends InstancedModel
     }
 
     public function paymentMethods() : BelongsToMany {
-        return $this->belongsToMany(AvailablePaymentMethod::class, 'event_payment_methods', 'event_id', 'available_payment_method_id')->withTimestamps();
+        // Pivot verknüpft über den Slug (payment_methods.slug), nicht über die numerische id
+        // von available_payment_methods -- die tenant-spezifische Instanz wird dadurch implizit
+        // über den globalen SiteScope von AvailablePaymentMethod (gefiltert auf app('tenant')) aufgelöst.
+        return $this->belongsToMany(AvailablePaymentMethod::class, 'event_payment_methods', 'event_id', 'slug', 'id', 'slug')->withTimestamps();
     }
 
     public function resetContributingLocalGroups() {

app/RelationModels/EventPaymentMethods.php

@@ -7,5 +7,5 @@ use App\Scopes\CommonModel;
 class EventPaymentMethods extends CommonModel
 {
     protected $table = 'event_payment_methods';
-    protected $fillable = ['event_id', 'available_payment_method_id'];
+    protected $fillable = ['event_id', 'slug'];
 }

database/migrations/2026_07_28_140020_create_event_payment_methods.php

@@ -12,8 +12,11 @@ return new class extends Migration {
         Schema::create('event_payment_methods', function (Blueprint $table) {
             $table->id();
             $table->foreignId('event_id')->constrained('events', 'id')->restrictOnDelete()->cascadeOnUpdate();
-            $table->foreignId('available_payment_method_id')->constrained('available_payment_methods', 'id')->restrictOnDelete()->cascadeOnUpdate();
+            $table->string('slug');
             $table->timestamps();
+
+            $table->foreign('slug')->references('slug')->on('payment_methods')->restrictOnDelete()->cascadeOnUpdate();
+            $table->unique(['event_id', 'slug']);
         });
     }