import * as fs from 'fs';
import * as path from 'path';
import { CONTROLLER_KEY, getClassMetadata } from '@midwayjs/core';
import { BaseController, CurdOption } from '@cool-midway/core';
import { AiKnowledgeService } from '../../../src/modules/ai/service/knowledge';
import {
  AdminAiKnowledgeController,
  adminAiKnowledgeCurdOption,
} from '../../../src/modules/ai/controller/admin/knowledge';
import { KnowledgeChunk } from '../../../src/comm/types/omni';

interface CoolControllerMeta {
  prefix?: string;
  curdOption?: CurdOption;
}

async function waitCoolMeta(
  target: new (...args: never[]) => unknown
): Promise<CoolControllerMeta> {
  const started = Date.now();
  while (Date.now() - started < 2000) {
    const meta = getClassMetadata(CONTROLLER_KEY, target) as
      | CoolControllerMeta
      | undefined;
    if (meta?.curdOption) {
      return meta;
    }
    await new Promise<void>(resolve => setImmediate(resolve));
  }
  throw new Error(`${target.name} 的 CoolController 元数据未就绪`);
}

function serviceApiMethods(apis: CurdOption['serviceApis'] = []): string[] {
  return apis.map(api => (typeof api === 'string' ? api : api.method));
}

describe('Point 07: AI 知识库分块切片与召回沙盒 (modules/ai knowledge sandbox)', () => {
  let service: AiKnowledgeService;

  beforeEach(() => {
    service = new AiKnowledgeService();
  });

  describe('1. splitTextToChunks 切片算法边界', () => {
    it('空文本或空白文本应返回空数组', () => {
      expect(service.splitTextToChunks('')).toEqual([]);
      expect(service.splitTextToChunks('   \n\t  ')).toEqual([]);
    });

    it('小文本边界：文本长度 <= chunkSize 应返回单一切片', () => {
      const text = 'OmniCard 全球数字名片';
      const chunks = service.splitTextToChunks(text, 50, 10);
      expect(chunks).toHaveLength(1);
      expect(chunks[0].content).toBe(text);
      expect(chunks[0].index).toBe(0);
      expect(chunks[0].length).toBe(text.length);
    });

    it('长文本滑动切片：验证切片数、重叠字符与末尾覆盖', () => {
      // 构造长度为 45 的文本
      const text = '1234567890abcdefghij1234567890abcdefghij12345';
      const chunkSize = 20;
      const overlap = 5;
      const chunks = service.splitTextToChunks(text, chunkSize, overlap);

      // step = 20 - 5 = 15:
      // chunk 0: [0, 20]
      // chunk 1: [15, 35]
      // chunk 2: [30, 45] (末尾到达 45)
      expect(chunks).toHaveLength(3);
      expect(chunks[0].content).toBe(text.slice(0, 20));
      expect(chunks[1].content).toBe(text.slice(15, 35));
      expect(chunks[2].content).toBe(text.slice(30, 45));

      // 验证重叠：chunk 0 的末尾 5 字符应等于 chunk 1 的开头 5 字符
      expect(chunks[0].content.slice(-5)).toBe(chunks[1].content.slice(0, 5));
      // 验证末尾完整覆盖
      expect(chunks[chunks.length - 1].content.endsWith('12345')).toBe(true);
    });

    it('重叠截断边界：overlap >= chunkSize 时应自动纠正步长，防止死循环', () => {
      const text = '这是一段用来测试重叠过大保护机制的测试长文本';
      // overlap 设为 30，大于 chunkSize 20
      const chunks = service.splitTextToChunks(text, 20, 30);
      expect(chunks.length).toBeGreaterThan(1);
      expect(chunks[0].length).toBeLessThanOrEqual(20);
    });

    it('未指定 chunkSize 与 overlap 时应具有合理默认值', () => {
      const longText = 'A'.repeat(500);
      const chunks = service.splitTextToChunks(longText);
      expect(chunks.length).toBeGreaterThan(1);
      expect(chunks[0].content.length).toBe(200);
    });
  });

  describe('2. simulateRetrieval 召回算法与排序计算', () => {
    const mockChunks: KnowledgeChunk[] = [
      {
        index: 0,
        content: 'OmniCard 提供 NFC 智能实体卡，碰一碰即可传输联系方式与微官网。',
        length: 37,
      },
      {
        index: 1,
        content: '雷达系统支持智能 CRM 访客轨迹追踪、停留时长与意向度自动评分。',
        length: 33,
      },
      {
        index: 2,
        content: 'AI 知识库提供文档分块切片预览与 RAG 检索增强沙盒调试能力。',
        length: 34,
      },
      {
        index: 3,
        content: 'Bento Grid 便当盒美学布局，响应式适配全球多语言及 RTL 界面。',
        length: 34,
      },
    ];

    it('空 query 或空 chunks 应返回空数组', () => {
      expect(service.simulateRetrieval('', mockChunks)).toEqual([]);
      expect(service.simulateRetrieval('NFC', [])).toEqual([]);
    });

    it('应按匹配置信度降序排序，完全匹配/高频命中排第一', () => {
      const query = 'NFC 实体卡 碰一碰';
      const results = service.simulateRetrieval(query, mockChunks, 3);
      expect(results.length).toBeGreaterThan(0);
      // 第一条应该是 index 为 0 的 NFC 相关切片
      expect(results[0].index).toBe(0);
      expect(results[0].score).toBeGreaterThan(0.5);
      expect(results[0].score).toBeLessThanOrEqual(1.0);
    });

    it('应支持 topK 截断返回数量', () => {
      const query = '系统 智能 适配';
      const results = service.simulateRetrieval(query, mockChunks, 2);
      expect(results.length).toBeLessThanOrEqual(2);
    });

    it('应支持 threshold 阈值过滤低相关度切片', () => {
      const query = 'RAG 沙盒调试';
      // 只有切片 2 高度匹配，设置高阈值过滤其他低分或无关切片
      const results = service.simulateRetrieval(query, mockChunks, 4, 0.4);
      expect(results).toHaveLength(1);
      expect(results[0].index).toBe(2);
      expect(results[0].content).toContain('RAG 检索增强沙盒调试');
    });

    it('应兼容接收纯字符串数组 chunks', () => {
      const stringChunks = [
        '国际多语言支持英文、中文、阿拉伯语',
        '国内网络环境配置说明',
      ];
      const results = service.simulateRetrieval('阿拉伯语 国际多语言', stringChunks, 2);
      expect(results.length).toBe(1);
      expect(results[0].content).toContain('阿拉伯语');
      expect(results[0].score).toBeGreaterThan(0);
    });
  });

  describe('3. AdminAiKnowledgeController 与 /admin/ai/knowledge/sandbox-test 接口', () => {
    const controllerFile = path.join(
      __dirname,
      '../../../src/modules/ai/controller/admin/knowledge.ts'
    );

    let meta: CoolControllerMeta;
    let option: CurdOption;

    beforeAll(async () => {
      meta = await waitCoolMeta(AdminAiKnowledgeController);
      option = meta.curdOption as CurdOption;
    });

    it('控制器文件与路由前缀符合规范', () => {
      expect(fs.existsSync(controllerFile)).toBe(true);
      expect(meta.prefix).toBe('/admin/ai/knowledge');
      expect(AdminAiKnowledgeController.prototype).toBeInstanceOf(BaseController);
    });

    it('serviceApis 应注册 sandboxTest，且控制器包含 sandboxTest 方法', () => {
      const methods = serviceApiMethods(option.serviceApis);
      expect(methods).toContain('sandboxTest');
      expect(typeof (AdminAiKnowledgeController.prototype as unknown as Record<string, unknown>).sandboxTest).toBe('function');
    });

    it('AiKnowledgeService.sandboxTest 应能执行切片并召回', async () => {
      const result = await service.sandboxTest({
        query: 'NFC 实体卡',
        content: 'OmniCard NFC 智能实体名片碰一碰极速交换。另有在线智能顾问与访客雷达。',
        chunkSize: 30,
        overlap: 5,
        topK: 2,
      });
      expect(result.totalChunks).toBeGreaterThan(0);
      expect(result.chunks.length).toBe(result.totalChunks);
      expect(result.recallList.length).toBeGreaterThan(0);
      expect(result.recallList[0].score).toBeGreaterThan(0);
    });
  });
});