decrypt notes

src/composables/useEncryption.ts

@@ -0,0 +1,44 @@
+import { doc, getDoc } from 'firebase/firestore'
+import { user, db } from '@/composables/useFirebase'
+import { decrypt, calculateClientKey } from '@/utils/crypto'
+
+function getClientKeysFromLocalStorage() {
+  try {
+    return JSON.parse(localStorage.getItem('clientKeys') || '{}')
+  } catch (e) {
+    return {}
+  }
+}
+
+export const getClientKey = (): ClientKey | void => {
+  if (!user.value) return
+  const clientKeys = getClientKeysFromLocalStorage()
+  const clientKey = clientKeys[user.value?.uid] || calculateClientKey('test')
+  return clientKey
+}
+
+export async function getEncryptionKey(): Promise<EncryptionKey | void> {
+  if (!user.value) return
+  const clientKey = getClientKey()
+  if (!db.value || !clientKey) return
+  const data = (await getDoc(doc(db.value, 'encryptionKeys', user.value?.uid || ''))).data()
+  if (!data) return
+  const { key } = data
+  const encryptionKey: EncryptionKey = decrypt(key, clientKey)
+  return encryptionKey
+}
+
+const decryptNote = (note: BaseNote, key: EncryptionKey) => {
+  return {
+    ...note,
+    title: decrypt(note.title, key),
+    content: decrypt(note.content, key)
+  }
+}
+
+export const decryptNotes = (notes: BaseNotes, encryptionKey: EncryptionKey) => {
+  const decryptedNotes = Object.fromEntries(
+    Object.entries(notes).map(([noteId, note]) => [noteId, { ...decryptNote(note, encryptionKey) }])
+  )
+  return decryptedNotes
+}