Add PayPal support for add-on and gift voucher checkout

app/Services/PayPal/PayPalOrderService.php

@@ -72,6 +72,61 @@ class PayPalOrderService
         return $this->client->post('/v2/checkout/orders', $payload, $headers);
     }
 
+    /**
+     * @param  array{
+     *     custom_id?: string|null,
+     *     return_url?: string|null,
+     *     cancel_url?: string|null,
+     *     locale?: string|null,
+     *     request_id?: string|null
+     * }  $options
+     * @return array<string, mixed>
+     */
+    public function createSimpleOrder(
+        string $referenceId,
+        string $description,
+        float $amount,
+        string $currency,
+        array $options = [],
+    ): array {
+        $formattedAmount = $this->formatAmount($amount);
+        $currency = strtoupper($currency);
+
+        $purchaseUnit = array_filter([
+            'reference_id' => Str::limit($referenceId, 127, ''),
+            'description' => Str::limit($description, 127, ''),
+            'custom_id' => $options['custom_id'] ?? null,
+            'amount' => [
+                'currency_code' => $currency,
+                'value' => $formattedAmount,
+            ],
+        ], static fn ($value) => $value !== null && $value !== '');
+
+        $applicationContext = array_filter([
+            'brand_name' => config('app.name', 'Fotospiel'),
+            'landing_page' => 'NO_PREFERENCE',
+            'user_action' => 'PAY_NOW',
+            'shipping_preference' => 'NO_SHIPPING',
+            'locale' => $this->resolveLocale($options['locale'] ?? null),
+            'return_url' => $options['return_url'] ?? null,
+            'cancel_url' => $options['cancel_url'] ?? null,
+        ], static fn ($value) => $value !== null && $value !== '');
+
+        $payload = [
+            'intent' => 'CAPTURE',
+            'purchase_units' => [$purchaseUnit],
+            'application_context' => $applicationContext,
+        ];
+
+        $headers = [];
+        $requestId = $options['request_id'] ?? null;
+        if (is_string($requestId) && $requestId !== '') {
+            $headers['PayPal-Request-Id'] = $requestId;
+        }
+
+        return $this->client->post('/v2/checkout/orders', $payload, $headers);
+    }
+
     /**
      * @param  array{request_id?: string|null}  $options
      * @return array<string, mixed>