// @vitest-environment jsdom
import { act, renderHook } from "@testing-library/react";
import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";

import { useOutline } from "./useOutline";
import type { OutlineChapterView } from "@/lib/api/types";

// 后端客户端与 Toast 是 hook 的外部副作用边界，单测一律 mock。
const post = vi.fn();
const toast = vi.fn();
vi.mock("@/lib/api/client", () => ({ api: { POST: (...a: unknown[]) => post(...a) } }));
vi.mock("@/components/Toast", () => ({ useToast: () => toast }));

function makeChapter(no: number): OutlineChapterView {
  return { no, volume: 1 };
}

describe("useOutline", () => {
  beforeEach(() => {
    post.mockReset();
    toast.mockReset();
  });
  afterEach(() => vi.clearAllMocks());

  it("空初始：status=idle", () => {
    const { result } = renderHook(() => useOutline([]));
    expect(result.current.status).toBe("idle");
    expect(result.current.chapters).toEqual([]);
    expect(result.current.error).toBeNull();
  });

  it("非空初始：status=ready 并保留章节", () => {
    const initial = [makeChapter(1)];
    const { result } = renderHook(() => useOutline(initial));
    expect(result.current.status).toBe("ready");
    expect(result.current.chapters).toEqual(initial);
  });

  it("生成成功：status 走到 ready 并填充章节并弹成功 toast", async () => {
    const chapters = [makeChapter(1), makeChapter(2)];
    post.mockResolvedValue({ data: { chapters }, error: null });

    const { result } = renderHook(() => useOutline([]));
    await act(async () => {
      await result.current.generate("p1", 1);
    });

    expect(result.current.status).toBe("ready");
    expect(result.current.chapters).toEqual(chapters);
    expect(result.current.error).toBeNull();
    expect(toast).toHaveBeenCalledWith("大纲已生成", "success");
  });

  it("data.chapters 为空时章节回退为空数组", async () => {
    post.mockResolvedValue({ data: { chapters: null }, error: null });
    const { result } = renderHook(() => useOutline([]));
    await act(async () => {
      await result.current.generate("p1", 1);
    });
    expect(result.current.status).toBe("ready");
    expect(result.current.chapters).toEqual([]);
  });

  it("后端返回业务错误：status=error 并 surface 友好文案", async () => {
    post.mockResolvedValue({
      data: null,
      error: { error: { code: "LLM_UNAVAILABLE" } },
    });
    const { result } = renderHook(() => useOutline([]));
    await act(async () => {
      await result.current.generate("p1", 1);
    });

    expect(result.current.status).toBe("error");
    expect(result.current.error?.code).toBe("OUTLINE_FAILED");
    expect(result.current.error?.message).toContain("provider");
    expect(toast).toHaveBeenCalledWith(expect.any(String), "error");
  });

  it("data 为空且无 error 也走错误分支", async () => {
    post.mockResolvedValue({ data: null, error: null });
    const { result } = renderHook(() => useOutline([]));
    await act(async () => {
      await result.current.generate("p1", 1);
    });
    expect(result.current.status).toBe("error");
    expect(result.current.error?.code).toBe("OUTLINE_FAILED");
  });
});