star-chart-search-enhancer/tests/page-hook.test.ts

import { JSDOM } from "jsdom";
import { afterEach, beforeEach, describe, expect, test, vi } from "vitest";

import { installPageHook } from "../src/page/hook";
import {
  CANDIDATE_ANALYSIS_MESSAGE_TYPE,
  CANDIDATE_REQUEST_MESSAGE_TYPE,
  EXTENSION_MESSAGE_SOURCE,
  HOOK_READY_MESSAGE_TYPE,
  RESULT_MESSAGE_TYPE
} from "../src/shared/message-types";
import type { ExtractAfterSearchRatesResult } from "../src/shared/result-types";

describe("page hook", () => {
  let dom: JSDOM;

  beforeEach(() => {
    vi.useFakeTimers();
    dom = new JSDOM("", {
      url: "https://xingtu.cn/ad/creator/author-homepage/douyin-video/6629661559960371207"
    });
  });

  afterEach(() => {
    dom.window.close();
    vi.useRealTimers();
  });

  test("reads fetch bodies through response.clone() and leaves the original response intact", async () => {
    const payload = JSON.stringify({
      metrics: {
        personal_video_after_search_rate: "0.5% - 1%",
        single_video_after_search_rate: "1% - 2%"
      }
    });
    const response = new Response(payload, {
      headers: { "content-type": "application/json" },
      status: 200
    });
    const cloneSpy = vi.spyOn(response, "clone");
    const originalFetch = vi.fn().mockResolvedValue(response);
    const postMessage = vi.fn();

    installPageHook({
      extractAfterSearchRates: () => successExtraction(),
      postMessage,
      timeoutMs: 5_000,
      window: createHookWindow(dom.window, originalFetch)
    });

    const returnedResponse = await dom.window.fetch("https://api.xingtu.cn/creator/metrics");
    await vi.runAllTimersAsync();

    expect(cloneSpy).toHaveBeenCalledTimes(1);
    expect(await returnedResponse.text()).toBe(payload);
  });

  test("keeps requests alive if extraction throws", async () => {
    const response = new Response(JSON.stringify({ ok: true }), {
      headers: { "content-type": "application/json" },
      status: 200
    });
    const originalFetch = vi.fn().mockResolvedValue(response);

    installPageHook({
      extractAfterSearchRates: () => {
        throw new Error("boom");
      },
      postMessage: vi.fn(),
      timeoutMs: 5_000,
      window: createHookWindow(dom.window, originalFetch)
    });

    const returnedResponse = await dom.window.fetch("https://api.xingtu.cn/creator/metrics");

    expect(returnedResponse.status).toBe(200);
    expect(await returnedResponse.json()).toEqual({ ok: true });
  });

  test("posts a structured success result when extraction succeeds", async () => {
    const response = new Response(JSON.stringify({ any: "payload" }), {
      headers: { "content-type": "application/json" },
      status: 200
    });
    const postMessage = vi.fn();

    installPageHook({
      extractAfterSearchRates: () => successExtraction(),
      postMessage,
      timeoutMs: 5_000,
      window: createHookWindow(dom.window, vi.fn().mockResolvedValue(response))
    });

    await dom.window.fetch("https://api.xingtu.cn/creator/metrics");
    await vi.runAllTimersAsync();

    expect(postMessage).toHaveBeenCalledWith(
      expect.objectContaining({
        payload: expect.objectContaining({
          matchedRequestUrl: "https://api.xingtu.cn/creator/metrics",
          pageStarId: "6629661559960371207",
          routeKey:
            "6629661559960371207::/ad/creator/author-homepage/douyin-video/6629661559960371207::1",
          stage: "captured",
          success: true
        }),
        source: EXTENSION_MESSAGE_SOURCE,
        type: RESULT_MESSAGE_TYPE
      }),
      "*"
    );
  });

  test("posts one timeout result if no successful capture appears", async () => {
    const postMessage = vi.fn();

    installPageHook({
      extractAfterSearchRates: () => unmatchedExtraction(),
      postMessage,
      timeoutMs: 100,
      window: createHookWindow(dom.window, vi.fn())
    });

    await vi.advanceTimersByTimeAsync(100);

    expect(postMessage).toHaveBeenNthCalledWith(
      2,
      expect.objectContaining({
        payload: expect.objectContaining({
          reason: "Timed out waiting for after-search-rate capture",
          stage: "timeout",
          success: false
        }),
        source: EXTENSION_MESSAGE_SOURCE,
        type: RESULT_MESSAGE_TYPE
      }),
      "*"
    );
  });

  test("announces hook-ready immediately after installation", () => {
    const postMessage = vi.fn();

    installPageHook({
      extractAfterSearchRates: () => unmatchedExtraction(),
      postMessage,
      timeoutMs: 5_000,
      window: createHookWindow(dom.window, vi.fn())
    });

    expect(postMessage).toHaveBeenCalledWith(
      expect.objectContaining({
        payload: expect.objectContaining({
          pageStarId: "6629661559960371207",
          routeKey:
            "6629661559960371207::/ad/creator/author-homepage/douyin-video/6629661559960371207::1"
        }),
        source: EXTENSION_MESSAGE_SOURCE,
        type: HOOK_READY_MESSAGE_TYPE
      }),
      "*"
    );
  });

  test("emits a candidate-request diagnostic before extraction", async () => {
    const response = new Response(JSON.stringify({ any: "payload" }), {
      headers: { "content-type": "application/json" },
      status: 200
    });
    const postMessage = vi.fn();

    installPageHook({
      extractAfterSearchRates: () => unmatchedExtraction(),
      postMessage,
      timeoutMs: 5_000,
      window: createHookWindow(dom.window, vi.fn().mockResolvedValue(response))
    });

    await dom.window.fetch("https://api.xingtu.cn/creator/value");
    await vi.runAllTimersAsync();

    expect(postMessage).toHaveBeenCalledWith(
      expect.objectContaining({
        payload: expect.objectContaining({
          requestMethod: "GET",
          requestUrl: "https://api.xingtu.cn/creator/value",
          routeKey:
            "6629661559960371207::/ad/creator/author-homepage/douyin-video/6629661559960371207::1",
          status: 200
        }),
        source: EXTENSION_MESSAGE_SOURCE,
        type: CANDIDATE_REQUEST_MESSAGE_TYPE
      }),
      "*"
    );
  });

  test("emits a candidate-analysis diagnostic after evaluating a candidate response", async () => {
    const response = new Response(
      JSON.stringify({
        data: {
          avg_search_after_view_rate: 0.0015,
          avg_search_after_view_rate_rank_percent: 0.9
        },
        status_code: 0
      }),
      {
        headers: { "content-type": "application/json" },
        status: 200
      }
    );
    const postMessage = vi.fn();

    installPageHook({
      extractAfterSearchRates: () => unmatchedExtraction(),
      postMessage,
      timeoutMs: 5_000,
      window: createHookWindow(dom.window, vi.fn().mockResolvedValue(response))
    });

    await dom.window.fetch("https://api.xingtu.cn/creator/value");
    await vi.runAllTimersAsync();

    expect(postMessage).toHaveBeenCalledWith(
      expect.objectContaining({
        payload: expect.objectContaining({
          extractorLevel: "none",
          matched: false,
          requestUrl: "https://api.xingtu.cn/creator/value",
          routeKey:
            "6629661559960371207::/ad/creator/author-homepage/douyin-video/6629661559960371207::1",
          signalEntries: [
            "$.data.avg_search_after_view_rate=0.0015",
            "$.data.avg_search_after_view_rate_rank_percent=0.9"
          ],
          success: false,
          topLevelKeys: ["data", "status_code"]
        }),
        source: EXTENSION_MESSAGE_SOURCE,
        type: CANDIDATE_ANALYSIS_MESSAGE_TYPE
      }),
      "*"
    );
  });

  test("prevents duplicate patching", async () => {
    const response = new Response(JSON.stringify({ any: "payload" }), {
      headers: { "content-type": "application/json" },
      status: 200
    });
    const fetchSpy = vi.fn().mockResolvedValue(response);
    const postMessage = vi.fn();
    const hookWindow = createHookWindow(dom.window, fetchSpy);

    const firstInstall = installPageHook({
      extractAfterSearchRates: () => successExtraction(),
      postMessage,
      timeoutMs: 5_000,
      window: hookWindow
    });
    const secondInstall = installPageHook({
      extractAfterSearchRates: () => successExtraction(),
      postMessage,
      timeoutMs: 5_000,
      window: hookWindow
    });

    await dom.window.fetch("https://api.xingtu.cn/creator/metrics");
    await vi.runAllTimersAsync();

    expect(firstInstall.alreadyInstalled).toBe(false);
    expect(secondInstall.alreadyInstalled).toBe(true);
    expect(postMessage).toHaveBeenCalledTimes(4);
  });
});

function createHookWindow(window: Window, fetchImpl: typeof fetch) {
  Object.defineProperty(window, "fetch", {
    configurable: true,
    value: fetchImpl,
    writable: true
  });

  class FakeXMLHttpRequest {
    addEventListener() {}
    open() {}
    send() {}
  }

  Object.defineProperty(window, "XMLHttpRequest", {
    configurable: true,
    value: FakeXMLHttpRequest,
    writable: true
  });

  return window as Window &
    typeof globalThis & {
      XMLHttpRequest: typeof FakeXMLHttpRequest;
      fetch: typeof fetch;
    };
}

function successExtraction(): ExtractAfterSearchRatesResult {
  return {
    extractorLevel: "label-value",
    matched: true,
    rawPathHints: ["$.metrics[0]"],
    rates: {
      personalVideoAfterSearchRate: "0.5% - 1%",
      singleVideoAfterSearchRate: "1% - 2%"
    },
    success: true
  };
}

function unmatchedExtraction(): ExtractAfterSearchRatesResult {
  return {
    extractorLevel: "none",
    matched: false,
    rawPathHints: [],
    reason: "No signals found",
    success: false
  };
}