refactor: stricter domain: attachments

toju-app/src/app/domains/attachment/infrastructure/util/attachment-storage.util.ts

@@ -0,0 +1,43 @@
+const ROOM_NAME_SANITIZER = /[^\w.-]+/g;
+const STORED_FILENAME_SANITIZER = /[^\w.-]+/g;
+
+export function sanitizeAttachmentRoomName(roomName: string): string {
+  const sanitizedRoomName = roomName.trim().replace(ROOM_NAME_SANITIZER, '_');
+
+  return sanitizedRoomName || 'room';
+}
+
+export function resolveAttachmentStoredFilename(attachmentId: string, filename: string): string {
+  const sanitizedAttachmentId = attachmentId.trim().replace(STORED_FILENAME_SANITIZER, '_') || 'attachment';
+  const basename = filename.trim().split(/[\\/]/)
+    .pop() ?? '';
+  const extensionIndex = basename.lastIndexOf('.');
+
+  if (extensionIndex <= 0 || extensionIndex === basename.length - 1) {
+    return sanitizedAttachmentId;
+  }
+
+  const sanitizedExtension = basename.slice(extensionIndex)
+    .replace(STORED_FILENAME_SANITIZER, '_')
+    .toLowerCase();
+
+  return sanitizedExtension === '.'
+    ? sanitizedAttachmentId
+    : `${sanitizedAttachmentId}${sanitizedExtension}`;
+}
+
+export function resolveAttachmentStorageBucket(mime: string): 'video' | 'audio' | 'image' | 'files' {
+  if (mime.startsWith('video/')) {
+    return 'video';
+  }
+
+  if (mime.startsWith('audio/')) {
+    return 'audio';
+  }
+
+  if (mime.startsWith('image/')) {
+    return 'image';
+  }
+
+  return 'files';
+}