backend/e2e/chat-persistence.test.ts

/**
 * E2E: Chat persistence across page reloads.
 *
 * Validates: send message -> receive AI response -> reload -> conversation restored.
 * Uses mocked /api/chat endpoint via page.route() (no real LLM calls).
 */
import { test, expect } from "./fixtures.js";

test.describe("Chat persistence", () => {
  test("conversation survives page reload", async ({ appPage, serverUrl }) => {
    // 1. Open chat panel
    await appPage.click("[aria-label='AI Assistant']");
    const input = appPage.getByPlaceholder("Ask anything...");
    await expect(input).toBeVisible({ timeout: 3_000 });

    // 2. Send a message
    await input.fill("say hello");
    await input.press("Enter");

    // 3. Wait for AI response to appear
    await expect(appPage.locator("text=Hello! I'm the AI assistant.")).toBeVisible({ timeout: 10_000 });

    // 4. Wait for persistence to trigger (status transitions to "ready")
    await appPage.waitForTimeout(2_000);

    // 5. Verify localStorage has chat data
    const chatKeys = await appPage.evaluate(() =>
      Object.keys(localStorage).filter((k) => k.startsWith("chat:"))
    );
    expect(chatKeys.length).toBeGreaterThan(0);
    expect(chatKeys[0]).toMatch(/^chat:.+:article$/);

    // 6. Reload the page
    await appPage.reload();
    await appPage.waitForSelector("[aria-label='Undo']", { timeout: 15_000 });

    // 7. Re-open chat and verify conversation is restored
    await appPage.click("[aria-label='AI Assistant']");
    await expect(appPage.locator("text=say hello")).toBeVisible({ timeout: 5_000 });
    await expect(appPage.locator("text=Hello! I'm the AI assistant.")).toBeVisible({ timeout: 5_000 });
  });

  test("new conversation button clears messages", async ({ appPage }) => {
    // 1. Open chat and send a message
    await appPage.click("[aria-label='AI Assistant']");
    const input = appPage.getByPlaceholder("Ask anything...");
    await expect(input).toBeVisible({ timeout: 3_000 });
    await input.fill("test message");
    await input.press("Enter");
    await expect(appPage.locator("text=Hello! I'm the AI assistant.")).toBeVisible({ timeout: 10_000 });

    // Wait for persistence
    await appPage.waitForTimeout(2_000);

    // 2. Click "New conversation"
    await appPage.click("[aria-label='New conversation']");

    // 3. Verify the empty state is back
    await expect(
      appPage.locator("text=Ask me to write, edit, expand, or improve your article.")
    ).toBeVisible({ timeout: 3_000 });

    // 4. Verify localStorage was cleared
    const chatKeys = await appPage.evaluate(() =>
      Object.keys(localStorage).filter((k) => k.startsWith("chat:"))
    );
    expect(chatKeys.length).toBe(0);
  });

  test("stable user identity across reloads", async ({ appPage }) => {
    const userName1 = await appPage.evaluate(
      () => JSON.parse(localStorage.getItem("collab-editor:fallback-user")!).name
    );

    await appPage.reload();
    await appPage.waitForSelector("[aria-label='Undo']", { timeout: 15_000 });

    const userName2 = await appPage.evaluate(
      () => JSON.parse(localStorage.getItem("collab-editor:fallback-user")!).name
    );

    expect(userName1).toBe(userName2);
  });
});