add billable rate restriction interfaces for billing extension

app/Http/Controllers/Api/V1/Controller.php

@@ -4,6 +4,8 @@ declare(strict_types=1);
 
 namespace App\Http\Controllers\Api\V1;
 
+use App\Enums\Role;
+use App\Exceptions\Api\FeatureIsNotAvailableInFreePlanApiException;
 use App\Models\Organization;
 use App\Service\BillingContract;
 use App\Service\PermissionStore;
@@ -49,4 +51,30 @@ class Controller extends \App\Http\Controllers\Controller
     {
         return app(BillingContract::class)->hasSubscription($organization) || app(BillingContract::class)->hasTrial($organization);
     }
+
+    protected function canUseBillableRates(Organization $organization): bool
+    {
+        return app(BillingContract::class)->canUseBillableRates($organization);
+    }
+
+    protected function canSeeBillableRates(Organization $organization): bool
+    {
+        if (! $this->canUseBillableRates($organization)) {
+            return false;
+        }
+
+        return $this->member($organization)->role !== Role::Employee->value || $organization->employees_can_see_billable_rates;
+    }
+
+    /**
+     * Organizations that can not use billable rates may keep or remove an existing rate, but not set a new one
+     *
+     * @throws FeatureIsNotAvailableInFreePlanApiException
+     */
+    protected function checkBillableRateChange(Organization $organization, ?int $oldBillableRate, ?int $newBillableRate): void
+    {
+        if ($newBillableRate !== null && $newBillableRate !== $oldBillableRate && ! $this->canUseBillableRates($organization)) {
+            throw new FeatureIsNotAvailableInFreePlanApiException;
+        }
+    }
 }