fix(desktop): persist auth cookies with max age

apps/desktop/layer/main/src/lib/auth-cookies.test.ts

@@ -1,5 +1,5 @@
 import type { Session } from "electron"
-import { describe, expect, it, vi } from "vitest"
+import { beforeEach, describe, expect, it, vi } from "vitest"
 
 import {
   buildManagedAuthCookieHeader,
@@ -10,6 +10,10 @@ import {
 } from "./auth-cookies"
 
 describe("auth cookies", () => {
+  beforeEach(() => {
+    vi.useRealTimers()
+  })
+
   it("builds a cookie header from managed auth cookies only", () => {
     const header = buildManagedAuthCookieHeader([
       { name: "__Secure-better-auth.session_token", value: "session-token" },
@@ -104,6 +108,53 @@ describe("auth cookies", () => {
     expect(remove).not.toHaveBeenCalled()
   })
 
+  it("persists session token cookies across app restarts when the server sends Max-Age", async () => {
+    vi.useFakeTimers()
+    vi.setSystemTime(new Date("2026-05-12T00:00:00.000Z"))
+
+    const set = vi.fn().mockImplementation(async () => {})
+    const remove = vi.fn().mockImplementation(async () => {})
+    const get = vi.fn().mockResolvedValue([])
+
+    await persistManagedAuthCookiesFromSetCookieHeader({
+      apiURL: "https://api.folo.is",
+      session: {
+        cookies: { get, set, remove },
+      } as unknown as Session,
+      setCookieHeader:
+        "__Secure-better-auth.session_token=session-token; Max-Age=2592000; Path=/; HttpOnly; Secure; SameSite=None",
+    })
+
+    expect(set).toHaveBeenCalledWith(
+      expect.objectContaining({
+        name: "__Secure-better-auth.session_token",
+        value: "session-token",
+        expirationDate: 1_781_136_000,
+      }),
+    )
+  })
+
+  it("keeps rememberMe=false session token cookies session-scoped", async () => {
+    const set = vi.fn().mockImplementation(async () => {})
+    const remove = vi.fn().mockImplementation(async () => {})
+    const get = vi.fn().mockResolvedValue([])
+
+    await persistManagedAuthCookiesFromSetCookieHeader({
+      apiURL: "https://api.folo.is",
+      session: {
+        cookies: { get, set, remove },
+      } as unknown as Session,
+      setCookieHeader:
+        "__Secure-better-auth.session_token=session-token; Path=/; HttpOnly; Secure; SameSite=None",
+    })
+
+    expect(set).toHaveBeenCalledWith(
+      expect.not.objectContaining({
+        expirationDate: expect.any(Number),
+      }),
+    )
+  })
+
   it("removes stale duplicate session token cookies while keeping the secure host-only cookie", async () => {
     const remove = vi.fn().mockImplementation(async () => {})
     const get = vi.fn().mockResolvedValue([

apps/desktop/layer/main/src/lib/auth-cookies.ts

@@ -224,6 +224,18 @@ const shouldRemoveCookie = (cookie: ParsedSetCookie) => {
   return false
 }
 
+const getCookieExpirationDate = (cookie: ParsedSetCookie) => {
+  if (cookie.expirationDate !== undefined) {
+    return cookie.expirationDate
+  }
+
+  if (cookie.maxAge !== undefined && cookie.maxAge > 0) {
+    return Math.floor(Date.now() / 1000) + cookie.maxAge
+  }
+
+  return
+}
+
 export const getManagedAuthCookieNames = () => {
   return [...MANAGED_AUTH_COOKIE_NAMES]
 }
@@ -368,6 +380,7 @@ export const persistManagedAuthCookiesFromSetCookieHeader = async ({
       continue
     }
 
+    const expirationDate = getCookieExpirationDate(cookie)
     const details: CookiesSetDetails = {
       url: apiURL,
       name: cookie.name,
@@ -377,7 +390,7 @@ export const persistManagedAuthCookiesFromSetCookieHeader = async ({
       secure: cookie.secure,
       ...(cookie.sameSite ? { sameSite: cookie.sameSite } : {}),
       ...(cookie.domain ? { domain: cookie.domain } : {}),
-      ...(cookie.expirationDate ? { expirationDate: cookie.expirationDate } : {}),
+      ...(expirationDate ? { expirationDate } : {}),
     }
 
     await session.cookies.set(details)