import { expect, fakeServerState, gotoWorkbench, saveScreenshot, test } from "../fixtures/test";
import { selectors, sessionTab } from "../fixtures/selectors";

type FrameSample = {
  activeSessionId: string | null;
  loading: boolean;
  hasA: boolean;
  hasB: boolean;
  textPreview: string;
};

declare global {
  interface Window {
    __issue1536Sampling?: boolean;
    __issue1536Samples?: FrameSample[];
  }
}

test("session switch persists active session after reload", async ({ page }, testInfo) => {
  await gotoWorkbench(page);
  await expect(page.locator(sessionTab("ses_running"))).toHaveAttribute("data-active", "true");
  await saveScreenshot(page, testInfo, "session-switch-before");

  await page.locator(sessionTab("ses_completed")).click();
  await expect(page).toHaveURL(/\/workbench\/sessions\/ses_completed/u);
  await expect(page.locator(sessionTab("ses_completed"))).toHaveAttribute("data-active", "true");
  await expect(page.locator(`${selectors.messageCard}[data-role="agent"][data-status="completed"]`)).toContainText("构建和 Trace 渲染检查完成");
  await expect.poll(async () => (await fakeServerState(page)).legacyRequestLedger as unknown[]).toHaveLength(0);
  await saveScreenshot(page, testInfo, "session-switch-after");

  await page.reload();
  await expect(page.locator(sessionTab("ses_completed"))).toHaveAttribute("data-active", "true");
  await page.locator(selectors.sessionDetailToggle).click();
  await expect(page.locator(selectors.sessionDetailDialog)).toContainText("ses_completed");
  await expect(page.locator(`${selectors.traceTimeline}[data-status="completed"]`)).toBeVisible();
  await saveScreenshot(page, testInfo, "session-switch-reload");
});

test.describe("delayed session detail projection", () => {
  test.use({ scenarioId: "session-switch-delayed-detail-frame" });

  test("loading exit never flashes previous session messages under target session", async ({ page }, testInfo) => {
    await gotoWorkbench(page, "/workbench/sessions/ses_running");
    await expect(page.locator(sessionTab("ses_running"))).toHaveAttribute("data-active", "true");
    await expect(page.locator(selectors.conversationList)).toContainText("SESSION_A_ONLY");
    await saveScreenshot(page, testInfo, "session-switch-delayed-before");

    await page.evaluate(() => {
      const samples: FrameSample[] = [];
      const read = (): void => {
        const active = document.querySelector('.session-tab[data-active="true"]');
        const panel = document.querySelector("#conversation-list");
        const text = panel?.textContent ?? "";
        samples.push({
          activeSessionId: active?.getAttribute("data-session-id") ?? null,
          loading: Boolean(document.querySelector("#conversation-list .conversation-detail-loading")),
          hasA: text.includes("SESSION_A_ONLY"),
          hasB: text.includes("SESSION_B_ONLY"),
          textPreview: text.replace(/\s+/gu, " ").trim().slice(0, 160)
        });
      };
      const loop = (): void => {
        read();
        if (window.__issue1536Sampling === true) requestAnimationFrame(loop);
      };
      window.__issue1536Samples = samples;
      window.__issue1536Sampling = true;
      requestAnimationFrame(loop);
    });

    await page.locator(sessionTab("ses_completed")).click();
    await expect(page.locator(sessionTab("ses_completed"))).toHaveAttribute("data-active", "true");
    await expect(page.locator("#conversation-list .conversation-detail-loading")).toBeVisible();
    await saveScreenshot(page, testInfo, "session-switch-delayed-loading");

    await expect(page.locator("#conversation-list .conversation-detail-loading")).toHaveCount(0);
    await saveScreenshot(page, testInfo, "session-switch-delayed-first-non-loading");
    await expect(page.locator(selectors.conversationList)).toContainText("SESSION_B_ONLY");
    await saveScreenshot(page, testInfo, "session-switch-delayed-final");

    const samples = await page.evaluate(() => {
      window.__issue1536Sampling = false;
      return window.__issue1536Samples ?? [];
    }) as FrameSample[];
    await testInfo.attach("session-switch-delayed-frame-samples.json", {
      body: JSON.stringify(samples, null, 2),
      contentType: "application/json"
    });
    const targetFrames = samples.filter((sample) => sample.activeSessionId === "ses_completed");
    const leakedFrames = targetFrames.filter((sample) => sample.hasA);
    const firstNonLoadingTarget = targetFrames.find((sample) => !sample.loading);

    expect(leakedFrames, JSON.stringify(leakedFrames.slice(0, 5), null, 2)).toEqual([]);
    expect(firstNonLoadingTarget?.hasB, JSON.stringify(firstNonLoadingTarget ?? null, null, 2)).toBe(true);
    expect(samples.filter((sample) => sample.hasA && sample.hasB), "old and target messages must never share one frame").toEqual([]);
  });
});

test.describe("empty session switch target", () => {
  test.use({ scenarioId: "session-switch-empty-reload" });

  test("switching from a filled session to an empty session updates URL and reload target", async ({ page }, testInfo) => {
    await gotoWorkbench(page, "/workbench/sessions/ses_completed");
    await expect(page.locator(sessionTab("ses_completed"))).toHaveAttribute("data-active", "true");
    await expect(page.locator(`${selectors.messageCard}[data-role="agent"][data-status="completed"]`)).toBeVisible();

    await page.locator(sessionTab("ses_empty")).click();
    await expect(page).toHaveURL(/\/workbench\/sessions\/ses_empty$/u);
    await expect(page.locator(sessionTab("ses_empty"))).toHaveAttribute("data-active", "true");
    await expect(page.locator(selectors.messageCard)).toHaveCount(0);
    await expect.poll(async () => (await fakeServerState(page)).legacyRequestLedger as unknown[]).toHaveLength(0);

    await page.reload();
    await expect(page.locator(sessionTab("ses_empty"))).toHaveAttribute("data-active", "true");
    await expect(page.locator(selectors.messageCard)).toHaveCount(0);
    await saveScreenshot(page, testInfo, "session-switch-empty-reload");
  });

  test("switching back to a running session reflects URL before reload", async ({ page }) => {
    await gotoWorkbench(page, "/workbench/sessions/ses_running");
    await expect(page.locator(sessionTab("ses_running"))).toHaveAttribute("data-active", "true");
    await expect(page.locator(`${selectors.messageCard}[data-role="agent"][data-status="running"]`)).toBeVisible();

    await page.locator(sessionTab("ses_empty")).click();
    await expect(page).toHaveURL(/\/workbench\/sessions\/ses_empty/u);
    await expect(page.locator(selectors.messageCard)).toHaveCount(0);

    await page.locator(sessionTab("ses_running")).click();
    await expect(page).toHaveURL(/\/workbench\/sessions\/ses_running/u);
    await expect(page.locator(sessionTab("ses_running"))).toHaveAttribute("data-active", "true");
    await expect(page.locator(`${selectors.messageCard}[data-role="agent"][data-status="running"]`)).toBeVisible();

    await page.reload();
    await expect(page.locator(sessionTab("ses_running"))).toHaveAttribute("data-active", "true");
    await expect(page.locator(`${selectors.messageCard}[data-role="agent"][data-status="running"]`)).toBeVisible();
  });
});

test.describe("stale session detail isolation", () => {
  test.use({ scenarioId: "session-switch-detail-404-isolated" });

  test("session detail 404 keeps current rail usable and does not block later switches", async ({ page }) => {
    await gotoWorkbench(page, "/workbench/sessions/ses_completed");
    await expect(page.locator(sessionTab("ses_completed"))).toHaveAttribute("data-active", "true");
    await expect(page.locator(`${selectors.messageCard}[data-role="agent"][data-status="completed"]`)).toBeVisible();

    await gotoWorkbench(page, "/workbench/sessions/ses_stale_404");
    await expect(page.locator(".conversation-error-hint")).toContainText(/session URL not found|unavailable/u);
    await expect(page.locator(sessionTab("ses_completed"))).toHaveCount(1);

    await page.locator(sessionTab("ses_empty")).click();
    await expect(page).toHaveURL(/\/workbench\/sessions\/ses_empty/u);
    await expect(page.locator(sessionTab("ses_empty"))).toHaveAttribute("data-active", "true");
    await expect(page.locator(selectors.messageCard)).toHaveCount(0);

    await page.reload();
    await expect(page.locator(sessionTab("ses_empty"))).toHaveAttribute("data-active", "true");
    await expect(page.locator(selectors.sessionTabs)).not.toHaveAttribute("data-loading", "true");
  });
});