feat(config): add config vars for default permissions for special groups

Co-authored-by: Tilman Vatteroth <git@tilmanvatteroth.de>
Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>
Signed-off-by: Philip Molares <philip.molares@udo.edu>

src/config/default-access-permission.enum.ts

@@ -0,0 +1,26 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+export enum DefaultAccessPermission {
+  NONE = 'none',
+  READ = 'read',
+  WRITE = 'write',
+}
+
+export function getDefaultAccessPermissionOrdinal(
+  permission: DefaultAccessPermission,
+): number {
+  switch (permission) {
+    case DefaultAccessPermission.NONE:
+      return 0;
+    case DefaultAccessPermission.READ:
+      return 1;
+    case DefaultAccessPermission.WRITE:
+      return 2;
+    default:
+      throw Error('Unknown permission');
+  }
+}