import { describe, it, expect, beforeEach, afterEach, vi } from "vitest";

// index.ts 是 IIFE 打包入口：模块加载即读取全局队列、替换 g.ctk 并重放。
// 隔离手段：vi.resetModules() + 动态 import，每用例拿到全新模块级 transport 状态。
// startPageTracking 注册的 document/window 监听跨用例存留，用独立 siteId 过滤批次。

type Cmd = [string, unknown?];
type CtkFn = ((cmd: string, arg?: unknown) => void) & { q?: Cmd[] };
const g = globalThis as unknown as {
  ctk?: CtkFn;
  __ctk_ctx?: Record<string, unknown>;
};
const UUID_RE = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/;

let fetchMock: ReturnType<typeof vi.fn>;

/** 模拟宿主snippet：先以桩函数排队，再动态加载 index 模块（触发重放） */
async function loadSdk(q: Cmd[] = []) {
  vi.resetModules();
  const stub = (cmd: string, arg?: unknown) => {
    q.push([cmd, arg]);
  };
  stub.q = q;
  g.ctk = stub;
  await import("../src/index");
}

function bodiesOf(siteId: string) {
  return fetchMock.mock.calls
    .map((c) => JSON.parse(c[1].body as string))
    .filter((b: { site_id: string }) => b.site_id === siteId);
}

describe("index 入口", () => {
  beforeEach(() => {
    localStorage.clear();
    vi.useFakeTimers();
    fetchMock = vi.fn().mockResolvedValue({ ok: true, status: 200 } as Response);
    vi.stubGlobal("fetch", fetchMock);
    // happy-dom 的 sendBeacon 会发真实网络请求——整体替换（Task 14 注释警示）
    vi.stubGlobal("navigator", {
      userAgent:
        "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36",
      language: "zh-CN",
      hardwareConcurrency: 8,
      sendBeacon: vi.fn().mockReturnValue(true),
    });
  });
  afterEach(() => {
    vi.unstubAllGlobals();
    vi.useRealTimers();
    delete g.__ctk_ctx;
    delete (document as { hidden?: boolean }).hidden;
    delete (document as { referrer?: string }).referrer;
  });

  it("init 后 sdk_loaded 入队（含版本组：sdk_version/build_id/schema_version/config_version）", async () => {
    await loadSdk([["init", { siteId: "site-1", endpoint: "/e", flushMs: 60000 }]]);
    g.ctk!("flush");

    const bodies = bodiesOf("site-1");
    expect(bodies).toHaveLength(1);
    const loaded = bodies[0].events.find((e: { event_name: string }) => e.event_name === "sdk_loaded");
    expect(loaded).toBeTruthy();
    expect(loaded.properties.sdk_version).toBe("0.2.0");
    // build_id 由 vitest.config define 注入 "vitest"；无 define 环境兜底 "unknown"
    expect(loaded.properties.build_id).toBe("vitest");
    expect(loaded.properties.schema_version).toBe(2);
    expect(loaded.properties.config_version).toBe("1");
    expect(loaded.event_id).toMatch(UUID_RE);
  });

  it("批次 context 含设备环境 + referrer_domain/utm/path（首触归因链路）", async () => {
    Object.defineProperty(document, "referrer", {
      value: "https://news.example/a",
      configurable: true,
    });
    window.history.pushState({}, "", "/land?utm_source=ns&utm_campaign=m1");
    await loadSdk([["init", { siteId: "site-2", endpoint: "/e", flushMs: 60000 }]]);

    // __ctk_ctx 四类键齐全：设备环境 + referrer_domain + utm + path
    const ctx = g.__ctk_ctx!;
    expect(ctx.device_type).toBe("PC");
    expect(ctx.os).toBe("Windows");
    expect(ctx.browser).toBe("Chrome");
    expect(ctx.language).toBe("zh-CN");
    expect(typeof ctx.timezone).toBe("string");
    expect(ctx.screen).toMatch(/^\d+x\d+$/);
    expect(ctx.referrer_domain).toBe("news.example");
    expect(ctx.utm).toEqual({ utm_source: "ns", utm_campaign: "m1" });
    expect(ctx.path).toBe("/land?utm_source=ns&utm_campaign=m1");

    g.ctk!("flush"); // 原样透传进批次 body.context
    const bodies = bodiesOf("site-2");
    expect(bodies).toHaveLength(1);
    expect(bodies[0].context).toEqual(ctx);
  });

  it("localStorage 抛异常：15s 定时 flush 无未捕获异常，身份降级内存后事件照常发出", async () => {
    vi.stubGlobal("localStorage", {
      getItem: () => {
        throw new Error("denied");
      },
      setItem: () => {
        throw new Error("denied");
      },
      removeItem: () => {
        throw new Error("denied");
      },
      clear: () => {
        throw new Error("denied");
      },
    });
    const unhandled: unknown[] = [];
    const onRej = (e: unknown) => unhandled.push(e);
    // tsconfig 无 @types/node，经 globalThis 取 process（vitest node worker 内必在）
    const proc = (
      globalThis as {
        process?: {
          on(ev: "unhandledRejection", cb: (e: unknown) => void): void;
          off(ev: "unhandledRejection", cb: (e: unknown) => void): void;
        };
      }
    ).process;
    proc?.on("unhandledRejection", onRej);
    await loadSdk([["init", { siteId: "site-7", endpoint: "/e", flushMs: 15000 }]]);

    let syncErr: unknown;
    try {
      await vi.advanceTimersByTimeAsync(15000); // 定时 flush 到期
    } catch (e) {
      syncErr = e; // fake timers 会把定时回调内的同步异常抛到 advance 调用方
    }
    proc?.off("unhandledRejection", onRej);
    expect(syncErr).toBeUndefined();
    expect(unhandled).toEqual([]);

    const bodies = bodiesOf("site-7");
    expect(bodies).toHaveLength(1);
    expect(bodies[0].visitor_id).toMatch(UUID_RE); // 内存降级身份仍可用
    expect(bodies[0].session_id).toMatch(UUID_RE);
    expect(bodies[0].events.map((e: { event_name: string }) => e.event_name)).toEqual([
      "sdk_loaded",
      "page_view",
    ]);
  });

  it("UA-CH hints 异步并入 __ctk_ctx：晚于 init 到达，flush 时随批次 context 发出", async () => {
    // 1s 后才 resolve 的高熵桩（fake timers 控制）：保证 init 同步完成时 hints 确实未到
    (navigator as { userAgentData?: unknown }).userAgentData = {
      getHighEntropyValues: () =>
        new Promise((resolve) => setTimeout(() => resolve({ model: "Pixel 7", bitness: "64" }), 1000)),
    };
    await loadSdk([["init", { siteId: "site-hints", endpoint: "/e", flushMs: 60000 }]]);

    expect(g.__ctk_ctx!.device_model).toBeUndefined(); // hints 未到（1s < 已流逝 0ms）
    await vi.advanceTimersByTimeAsync(1000);           // hints 到达（先于 2s 超时）
    expect(g.__ctk_ctx!.device_model).toBe("Pixel 7");
    expect(g.__ctk_ctx!.platform_version).toBeUndefined(); // 未提供的键不挂

    g.ctk!("flush");
    const bodies = bodiesOf("site-hints");
    expect(bodies).toHaveLength(1);
    expect(bodies[0].context.device_model).toBe("Pixel 7"); // 并入后 flush 的批次携带
  });

  it("无 userAgentData 环境：hints 降级为空，__ctk_ctx 不挂键不崩（未捕获拒绝为零）", async () => {
    const unhandled: unknown[] = [];
    const onRej = (e: unknown) => unhandled.push(e);
    const proc = (globalThis as { process?: { on(ev: "unhandledRejection", cb: (e: unknown) => void): void; off(ev: "unhandledRejection", cb: (e: unknown) => void): void } }).process;
    proc?.on("unhandledRejection", onRej);
    await loadSdk([["init", { siteId: "site-nohints", endpoint: "/e", flushMs: 60000 }]]);
    await vi.advanceTimersByTimeAsync(2500); // 超过 2s 降级窗口
    proc?.off("unhandledRejection", onRej);

    expect("device_model" in (g.__ctk_ctx ?? {})).toBe(false);
    expect(unhandled).toEqual([]);
    g.ctk!("flush"); // 降级批次照常发送
    expect(bodiesOf("site-nohints")).toHaveLength(1);
  });

  it("init 前队列重放：排队的 track 事件入队，g.ctk 已替换为 dispatch", async () => {
    const trackEv = {
      event_id: "e-custom",
      event_name: "cta_click",
      occurred_at: new Date().toISOString(),
      path: "/x",
      title: "t",
      properties: { k: 1 },
    };
    await loadSdk([
      ["init", { siteId: "site-8", endpoint: "/e", flushMs: 60000 }],
      ["track", trackEv],
    ]);

    expect(typeof g.ctk).toBe("function");
    expect(g.ctk!.q).toBeUndefined(); // 桩（带 q）已被 dispatch 替换
    g.ctk!("flush");
    let bodies = bodiesOf("site-8");
    expect(bodies).toHaveLength(1);
    expect(bodies[0].events.map((e: { event_name: string }) => e.event_name)).toEqual([
      "sdk_loaded",
      "page_view",
      "cta_click",
    ]);
    expect(bodies[0].events[2].properties).toEqual({ k: 1 });

    // 重放结束后宿主新调用直接进 dispatch（不再排队丢失）
    g.ctk!("track", { ...trackEv, event_id: "e-2", event_name: "cta_click2" });
    g.ctk!("flush");
    bodies = bodiesOf("site-8");
    expect(bodies).toHaveLength(2);
    expect(bodies[1].events.map((e: { event_name: string }) => e.event_name)).toEqual(["cta_click2"]);
  });
});