feat(desktop): remember login credentials

apps/desktop-client/src/main/login-credentials.ts

@@ -0,0 +1,87 @@
+import { existsSync, readFileSync, rmSync, writeFileSync } from 'node:fs'
+import { join } from 'node:path'
+
+import { app, safeStorage } from 'electron/main'
+
+export interface DesktopLoginCredentials {
+  identifier: string
+  password: string
+}
+
+interface PersistedLoginCredentials {
+  version?: number
+  identifier?: unknown
+  encryptedPassword?: unknown
+}
+
+function credentialsPath(): string {
+  return join(app.getPath('userData'), 'login-credentials.json')
+}
+
+function normalizeCredentials(input: unknown): PersistedLoginCredentials {
+  if (!input || typeof input !== 'object') {
+    return {}
+  }
+  return input as PersistedLoginCredentials
+}
+
+export function getSavedLoginCredentials(): DesktopLoginCredentials | null {
+  try {
+    if (!existsSync(credentialsPath())) {
+      return null
+    }
+
+    const persisted = normalizeCredentials(JSON.parse(readFileSync(credentialsPath(), 'utf8')))
+    const identifier = typeof persisted.identifier === 'string' ? persisted.identifier : ''
+    const encryptedPassword =
+      typeof persisted.encryptedPassword === 'string' ? persisted.encryptedPassword : ''
+
+    if (!identifier || !encryptedPassword || !safeStorage.isEncryptionAvailable()) {
+      return null
+    }
+
+    const password = safeStorage.decryptString(Buffer.from(encryptedPassword, 'base64'))
+    return password ? { identifier, password } : null
+  } catch (error) {
+    console.warn('[login-credentials] read failed', {
+      message: error instanceof Error ? error.message : String(error),
+    })
+    return null
+  }
+}
+
+export function saveLoginCredentials(credentials: DesktopLoginCredentials): DesktopLoginCredentials {
+  const identifier = credentials.identifier.trim()
+  if (!identifier || !credentials.password) {
+    clearSavedLoginCredentials()
+    return { identifier: '', password: '' }
+  }
+
+  if (!safeStorage.isEncryptionAvailable()) {
+    throw new Error('login_credentials_encryption_unavailable')
+  }
+
+  const encryptedPassword = safeStorage.encryptString(credentials.password).toString('base64')
+  writeFileSync(
+    credentialsPath(),
+    JSON.stringify({
+      version: 1,
+      identifier,
+      encryptedPassword,
+      updatedAt: new Date().toISOString(),
+    }),
+    'utf8',
+  )
+  return { identifier, password: credentials.password }
+}
+
+export function clearSavedLoginCredentials(): null {
+  try {
+    rmSync(credentialsPath(), { force: true })
+  } catch (error) {
+    console.warn('[login-credentials] clear failed', {
+      message: error instanceof Error ? error.message : String(error),
+    })
+  }
+  return null
+}