/**
 * TitleGenerator 测试（v0.7.3 P4-1）
 *
 * T1 sanitizeTitle 清洗规则矩阵（围栏/引号/自述前缀/空白/截断/空值）；
 * T2 maybeGenerateTitle 幂等（每会话仅一次）；
 * T3 已有自定义标题的会话不覆盖；
 * T4 LLM 失败/超时静默回退（不抛错，返回 null）；
 * T5 空输入门控。
 */

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

vi.mock('electron-log', () => ({
  default: { info: vi.fn(), warn: vi.fn(), error: vi.fn(), debug: vi.fn() },
}));

import { TitleGenerator, sanitizeTitle } from '../title-generator.service';
import type { IMetonaProviderAdapter, MetonaResponse } from '../../harness/types';

describe('sanitizeTitle', () => {
  it('T1a: 干净文本原样通过', () => {
    expect(sanitizeTitle('修复登录超时')).toBe('修复登录超时');
  });

  it('T1b: markdown 围栏与列表标记剥离', () => {
    expect(sanitizeTitle('```json\n"标题"\n```')).toBe('标题');
    expect(sanitizeTitle('- 修复登录超时')).toBe('修复登录超时');
    expect(sanitizeTitle('# 修复登录超时')).toBe('修复登录超时');
  });

  it('T1c: 成对包裹引号剥离', () => {
    expect(sanitizeTitle('"修复登录超时"')).toBe('修复登录超时');
    expect(sanitizeTitle('“修复登录超时”')).toBe('修复登录超时');
  });

  it('T1d: 自述前缀剥离（标题:/Title:）', () => {
    expect(sanitizeTitle('标题: 修复登录超时')).toBe('修复登录超时');
    expect(sanitizeTitle('Title: Fix login timeout')).toBe('Fix login timeout');
  });

  it('T1e: 换行折叠为空格、首尾空白去除', () => {
    expect(sanitizeTitle('修复\n登录  超时\n')).toBe('修复 登录 超时');
  });

  it('T1f: 超长截断到 maxLen', () => {
    const out = sanitizeTitle('a'.repeat(100), 40);
    expect(out?.length).toBe(40);
  });

  it('T1g: 空值/纯符号 → null', () => {
    expect(sanitizeTitle('')).toBeNull();
    expect(sanitizeTitle('   ')).toBeNull();
    expect(sanitizeTitle('"""')).toBeNull();
    expect(sanitizeTitle('###')).toBeNull();
  });
});

function makeAdapter(content: string | Error): IMetonaProviderAdapter {
  return {
    providerId: 'mock',
    supportedModels: ['m'],
    supportsToolCalling: true,
    supportsThinking: false,
    getContextWindow: () => 128_000,
    send: vi.fn(async (): Promise<MetonaResponse> => {
      if (content instanceof Error) throw content;
      return {
        meta: { requestId: 'r', provider: 'mock', model: 'm', latencyMs: 1, timestamp: Date.now() },
        content,
        usage: { inputTokens: 1, outputTokens: 1, totalTokens: 2 },
        finishReason: 'stop' as never,
      };
    }),
    sendStream: vi.fn(),
    setAbortSignal: vi.fn(),
    healthCheck: async () => true,
  } as unknown as IMetonaProviderAdapter;
}

function makeSessionService(existing: Array<{ id: string; title: string }> = []) {
  // 注意：真实 SessionService.list() 是同步方法（better-sqlite3），
  // mock 必须保持同步返回，否则 generate 内的 .find() 拿到 Promise
  return {
    list: vi.fn(() => existing) as unknown as () => Array<{ id: string; title: string }>,
    rename: vi.fn(() => true),
  };
}

describe('TitleGenerator.maybeGenerateTitle', () => {
  beforeEach(() => {
    vi.useFakeTimers();
  });
  afterEach(() => {
    vi.useRealTimers();
  });

  it('T2: 首个 run 生成标题并调用 rename；同会话幂等', async () => {
    const svc = makeSessionService([{ id: 's1', title: '新会话' }]);
    const gen = new TitleGenerator(() => makeAdapter('修复登录超时'), svc as never);
    const title = await gen.maybeGenerateTitle(
      's1',
      '帮我看看为什么登录会超时',
      '已定位为 token 过期…',
    );
    expect(title).toBe('修复登录超时');
    expect(svc.rename).toHaveBeenCalledWith('s1', '修复登录超时');

    // 第二次调用（同会话）幂等 —— 不再调用 LLM
    const second = await gen.maybeGenerateTitle('s1', '再问一次', '再答一次');
    expect(second).toBeNull();
  });

  it('T3: 已有自定义标题的会话不覆盖', async () => {
    const svc = makeSessionService([{ id: 's1', title: '用户手动命名' }]);
    const adapterSend = vi.fn();
    const adapter = makeAdapter('不应被使用');
    (adapter.send as ReturnType<typeof vi.fn>).mockImplementation(async (...args: unknown[]) => {
      adapterSend(...args);
      throw new Error('should not be called');
    });
    const gen = new TitleGenerator(() => adapter, svc as never);
    const title = await gen.maybeGenerateTitle('s1', '内容', '回答');
    expect(title).toBeNull();
    expect(adapterSend).not.toHaveBeenCalled();
  });

  it('T4: LLM 失败静默回退（返回 null，不抛错），且同会话不重试', async () => {
    const svc = makeSessionService([{ id: 's1', title: '新会话' }]);
    const gen = new TitleGenerator(() => makeAdapter(new Error('network down')), svc as never);
    await expect(gen.maybeGenerateTitle('s1', 'q', 'a')).resolves.toBeNull();
    await expect(gen.maybeGenerateTitle('s1', 'q2', 'a2')).resolves.toBeNull();
    expect(svc.rename).not.toHaveBeenCalled();
  });

  it('T5: 空 sessionId / 双向空内容 → 不生成', async () => {
    const svc = makeSessionService();
    const adapter = makeAdapter('x');
    const gen = new TitleGenerator(() => adapter, svc as never);
    expect(await gen.maybeGenerateTitle('', 'q', 'a')).toBeNull();
    expect(await gen.maybeGenerateTitle('s1', '  ', '  ')).toBeNull();
  });

  it('T6: 并发重入复用同一 Promise（不重复调用 LLM）', async () => {
    const svc = makeSessionService([{ id: 's1', title: '新会话' }]);
    const gen = new TitleGenerator(() => makeAdapter('并发标题'), svc as never);
    // 使用真实定时器场景下并发触发
    vi.useRealTimers();
    const [a, b] = await Promise.all([
      gen.maybeGenerateTitle('s2', 'q', 'a'),
      gen.maybeGenerateTitle('s2', 'q', 'a'),
    ]);
    expect(a).toBe('并发标题');
    expect(b).toBe('并发标题');
    // rename 仅一次（并发重入复用）
    expect(svc.rename).toHaveBeenCalledTimes(1);
  });
});