feat:Lib Files

frontend/lib/indexeddb.ts

@@ -0,0 +1,73 @@
+/**
+ * IndexedDB utilities for caching uploaded files
+ */
+
+const DB_NAME = 'NordicPrivacyAI';
+const STORE_NAME = 'uploads';
+const DB_VERSION = 1;
+
+function openDB(): Promise<IDBDatabase> {
+  return new Promise((resolve, reject) => {
+    const request = indexedDB.open(DB_NAME, DB_VERSION);
+    
+    request.onerror = () => reject(request.error);
+    request.onsuccess = () => resolve(request.result);
+    
+    request.onupgradeneeded = (event) => {
+      const db = (event.target as IDBOpenDBRequest).result;
+      if (!db.objectStoreNames.contains(STORE_NAME)) {
+        db.createObjectStore(STORE_NAME);
+      }
+    };
+  });
+}
+
+export interface UploadedFileMeta {
+  name: string;
+  size: number;
+  type: string;
+  contentPreview: string;
+}
+
+export async function saveLatestUpload(file: File, meta: UploadedFileMeta): Promise<void> {
+  const db = await openDB();
+  const transaction = db.transaction([STORE_NAME], 'readwrite');
+  const store = transaction.objectStore(STORE_NAME);
+  
+  await new Promise((resolve, reject) => {
+    const request = store.put({ file, meta }, 'latest');
+    request.onsuccess = () => resolve(undefined);
+    request.onerror = () => reject(request.error);
+  });
+  
+  db.close();
+}
+
+export async function getLatestUpload(): Promise<{ file: File; meta: UploadedFileMeta } | { file: null; meta: null }> {
+  const db = await openDB();
+  const transaction = db.transaction([STORE_NAME], 'readonly');
+  const store = transaction.objectStore(STORE_NAME);
+  
+  const result = await new Promise<any>((resolve, reject) => {
+    const request = store.get('latest');
+    request.onsuccess = () => resolve(request.result);
+    request.onerror = () => reject(request.error);
+  });
+  
+  db.close();
+  return result || { file: null, meta: null };
+}
+
+export async function deleteLatestUpload(): Promise<void> {
+  const db = await openDB();
+  const transaction = db.transaction([STORE_NAME], 'readwrite');
+  const store = transaction.objectStore(STORE_NAME);
+  
+  await new Promise((resolve, reject) => {
+    const request = store.delete('latest');
+    request.onsuccess = () => resolve(undefined);
+    request.onerror = () => reject(request.error);
+  });
+  
+  db.close();
+}