import { randomUUID } from 'crypto';

import { INestApplication, ValidationPipe } from '@nestjs/common';
import { Reflector } from '@nestjs/core';
import { Test, TestingModule } from '@nestjs/testing';
import { getStorageToken } from '@nestjs/throttler';
import request from 'supertest';
import type { Response } from 'supertest';
import { App } from 'supertest/types';
import { DataSource } from 'typeorm';

import { AppModule } from '@/app.module';
import { HttpExceptionFilter } from '@/common/filters/http-exception.filter';
import { TransformInterceptor } from '@/common/interceptors/transform.interceptor';
import { RequestIdMiddleware } from '@/common/middleware/request-id.middleware';
import {
  AiUnavailableError,
  COURSE_AI_CLIENT,
  type CourseAiClient,
  type CourseDraftInput,
} from '@/modules/course-generation/ai/course-ai.client';
import { FakeCourseAiClient } from '@/modules/course-generation/ai/fake-course-ai.client';
import { hashDeviceId } from '@/modules/course-generation/device-id.decorator';
import { Place } from '@/modules/place/entities/place.entity';
import { WeatherService } from '@/modules/weather/weather.service';
import { kstDateString } from '@/shared/utils/kst';
import { parseOpeningHours } from '@/shared/utils/opening-hours';

/**
 * AI 코스 생성 API 계약 — 횟수·접수·진행 조회·결과·취소·평가·실패 코드를 실제 HTTP·DB 로 검증한다.
 * 시험 장소는 대구 영역 사각형(geo.ts) 남서쪽 끝(실제로는 대구 밖이라 장소 데이터가 없는 곳)에 만들고(source_id 'e2e-cg-'),
 * 끝나면 지운다. AI 는 가짜(조절 가능), 날씨는 null 로 바꿔 키 없이 돈다.
 */
const C = { lat: 35.56, lng: 128.31 };
/** 후보가 없는 곳(5km 떨어짐) */
const EMPTY = { lat: 35.6, lng: 128.36 };
const DEVICE_HEADER = 'X-Device-Id';
const TERMINAL = ['succeeded', 'failed', 'canceled'];

type Mode = 'normal' | 'block' | 'unavailable';

/** 가짜 AI 를 감싸 시험마다 막아 두거나(block) 쓸 수 없게(unavailable) 한다 */
class ControllableAi implements CourseAiClient {
  mode: Mode = 'normal';
  private readonly fake = new FakeCourseAiClient();

  draftCourse(input: CourseDraftInput) {
    if (this.mode === 'unavailable') {
      return Promise.reject(new AiUnavailableError('시험: AI 장애'));
    }
    if (this.mode === 'block') {
      return new Promise<never>((_, reject) => {
        input.signal.addEventListener('abort', () =>
          reject(new Error('시험: 끊김')),
        );
      });
    }
    return this.fake.draftCourse(input);
  }

  parseConditions(input: Parameters<CourseAiClient['parseConditions']>[0]) {
    return this.fake.parseConditions(input);
  }
}

interface Envelope<T> {
  success: boolean;
  data: T;
  error?: { code: string };
}
interface GenerationBody {
  id: string;
  status: string;
  stage: string | null;
  progress: { found: number | null; kept: number | null };
  remaining: number;
  rating: string | null;
  failure: { code: string; notices: string[] } | null;
  result: {
    outcome: string;
    window: { date: string; start: string; end: string };
    totals: { stops: number };
    stops: {
      id: string;
      arrive: string;
      leave: string;
      minutes: number;
      legToNext: { minutes: number; mode: string } | null;
    }[];
    alternates: { forIndex: number }[];
  } | null;
}
const body = <T>(res: Response) => res.body as Envelope<T>;

describe('AI 코스 생성 API (e2e)', () => {
  let app: INestApplication<App>;
  let ds: DataSource;
  const ai = new ControllableAi();
  const devices: string[] = [];
  const placeIds: string[] = [];
  const date = kstDateString(new Date(), 1);

  const device = () => {
    const id = randomUUID();
    devices.push(id);
    return id;
  };
  const conditions = (overrides: Record<string, unknown> = {}) => ({
    area: { type: 'point', ...C },
    date,
    start: '13:00',
    end: '19:00',
    party: 2,
    pet: null,
    mobility: 'walk',
    indoorIfRain: true,
    ...overrides,
  });
  const create = (deviceId: string, overrides: Record<string, unknown> = {}) =>
    request(app.getHttpServer())
      .post('/api/course-generations')
      .set(DEVICE_HEADER, deviceId)
      .send({ request: '', conditions: conditions(overrides) });
  const get = (deviceId: string, id: string) =>
    request(app.getHttpServer())
      .get(`/api/course-generations/${id}`)
      .set(DEVICE_HEADER, deviceId);

  /** 끝날 때까지(또는 원하는 상태까지) 조회한다 */
  async function waitFor(
    deviceId: string,
    id: string,
    until: (g: GenerationBody) => boolean = (g) => TERMINAL.includes(g.status),
  ): Promise<GenerationBody> {
    for (let i = 0; i < 100; i++) {
      const res = await get(deviceId, id).expect(200);
      const generation = body<GenerationBody>(res).data;
      if (until(generation)) return generation;
      await new Promise((resolve) => setTimeout(resolve, 100));
    }
    throw new Error(`생성 ${id} 이 끝나지 않았다`);
  }

  async function cleanup(): Promise<void> {
    if (devices.length > 0) {
      await ds.query(
        `DELETE FROM ai_course_generation WHERE device_hash = ANY($1)`,
        [devices.map(hashDeviceId)],
      );
    }
    await ds.query(`DELETE FROM place WHERE source_id LIKE 'e2e-cg-%'`);
  }

  beforeAll(async () => {
    const moduleFixture: TestingModule = await Test.createTestingModule({
      imports: [AppModule],
    })
      .overrideProvider(COURSE_AI_CLIENT)
      .useValue(ai)
      .overrideProvider(WeatherService)
      .useValue({ forecastWindow: () => Promise.resolve(null) })
      // 시험 요청은 모두 같은 주소에서 온다 — 분당 요청 제한(생성 5회)을 세지 않는다
      .overrideProvider(getStorageToken())
      .useValue({
        increment: () =>
          Promise.resolve({
            totalHits: 1,
            timeToExpire: 60,
            isBlocked: false,
            timeToBlockExpire: 0,
          }),
      })
      .compile();
    // 운영처럼 마이그레이션을 기동 훅보다 먼저 돌린다 — 빈 DB 에서 실행기의 기동 정리가 테이블을 찾는다
    ds = moduleFixture.get(DataSource);
    await ds.runMigrations();
    app = moduleFixture.createNestApplication();
    app.setGlobalPrefix('api');
    app.use(new RequestIdMiddleware().use.bind(new RequestIdMiddleware()));
    app.useGlobalPipes(
      new ValidationPipe({
        whitelist: true,
        forbidNonWhitelisted: true,
        transform: true,
      }),
    );
    app.useGlobalFilters(new HttpExceptionFilter());
    app.useGlobalInterceptors(new TransformInterceptor(app.get(Reflector)));
    await app.init();
    await cleanup();

    const places = ds.getRepository(Place);
    const rows: [string, Place['category'], string, number][] = [
      ['1', 'attraction', '상시 개방', 0],
      ['2', 'cafe', '10:00~22:00', 0.002],
      ['3', 'culture', '09:00~22:00', 0.004],
      ['4', 'food', '11:00~22:00', 0.006],
      ['5', 'nature', '상시 개방', -0.002],
      ['6', 'cafe', '10:00~22:00', -0.004],
    ];
    for (const [key, category, hours, dLat] of rows) {
      const saved = await places.save(
        places.create({
          source: 'tour',
          sourceId: `e2e-cg-${key}`,
          category,
          name: `이투이 코스 ${key}`,
          lat: C.lat + dLat,
          lng: C.lng,
          publicHoursText: hours,
          publicHours: parseOpeningHours(hours, '연중무휴'),
        }),
      );
      placeIds.push(saved.id);
    }
  });

  afterAll(async () => {
    // 준비가 실패해도 앱은 닫는다 — 닫지 않으면 주기 작업이 남아 jest 가 끝나지 않는다
    try {
      await cleanup();
    } finally {
      await app.close();
    }
  });

  afterEach(() => {
    ai.mode = 'normal';
  });

  it('X-Device-Id 가 없거나 UUID 가 아니면 VAL_001', async () => {
    const missing = await request(app.getHttpServer())
      .get('/api/course-generations/quota')
      .expect(400);
    expect(body(missing).error?.code).toBe('VAL_001');
    const wrong = await request(app.getHttpServer())
      .get('/api/course-generations/quota')
      .set(DEVICE_HEADER, 'not-a-uuid')
      .expect(400);
    expect(body(wrong).error?.code).toBe('VAL_001');
  });

  it('오늘 남은 횟수 — 비로그인 하루 2번', async () => {
    const res = await request(app.getHttpServer())
      .get('/api/course-generations/quota')
      .set(DEVICE_HEADER, device())
      .expect(200);
    expect(body(res).data).toMatchObject({
      limit: 2,
      used: 0,
      remaining: 2,
      tier: 'guest',
    });
  });

  it('조건 해석 — 비어 있는 항목은 기본값으로 채우고, 대구 밖 기준 위치는 VAL_001', async () => {
    const res = await request(app.getHttpServer())
      .post('/api/course-conditions')
      .set(DEVICE_HEADER, device())
      .send({
        text: '토요일에 걷기 좋은 곳',
        baseArea: { type: 'point', ...C },
      })
      .expect(200);
    expect(body(res).data).toMatchObject({
      conditions: {
        area: { type: 'point', ...C },
        party: 2,
        pet: null,
        mobility: 'walk',
        indoorIfRain: true,
      },
      inferred: [],
      issues: [],
      weather: null,
    });
    const outside = await request(app.getHttpServer())
      .post('/api/course-conditions')
      .set(DEVICE_HEADER, device())
      .send({
        text: '',
        baseArea: { type: 'point', lat: 37.5665, lng: 126.978 },
      })
      .expect(400);
    expect(body(outside).error?.code).toBe('VAL_001');
  });

  it('생성을 접수하고 진행을 조회하면 결과가 나오고, 그때 횟수를 차감한다', async () => {
    const me = device();
    const created = await request(app.getHttpServer())
      .post('/api/course-generations')
      .set(DEVICE_HEADER, me)
      .send({
        request: '연락은 010-1234-5678 로, 산책하고 카페',
        conditions: conditions(),
      })
      .expect(201);
    const { id, status, remaining } = body<{
      id: string;
      status: string;
      remaining: number;
    }>(created).data;
    expect(status).toBe('queued');
    expect(remaining).toBe(2);

    const done = await waitFor(me, id);
    expect(done.status).toBe('succeeded');
    expect(done.remaining).toBe(1);
    expect(done.progress.found).toBe(6);
    const result = done.result!;
    expect(result.window).toEqual({ date, start: '13:00', end: '19:00' });
    expect(result.stops.length).toBeGreaterThanOrEqual(2);
    expect(result.totals.stops).toBe(result.stops.length);
    for (const [i, stop] of result.stops.entries()) {
      expect(placeIds).toContain(stop.id);
      expect(Date.parse(stop.leave) - Date.parse(stop.arrive)).toBe(
        stop.minutes * 60_000,
      );
      const next = result.stops[i + 1];
      if (next) {
        expect(Date.parse(next.arrive)).toBe(
          Date.parse(stop.leave) + stop.legToNext!.minutes * 60_000,
        );
      }
    }

    // 요청 문장의 전화번호는 가려서, 현재 위치는 약 100m 단위로 저장한다
    const [row] = await ds.query<
      {
        request_text: string;
        counted: boolean;
        conditions: { area: unknown };
      }[]
    >(
      `SELECT request_text, counted, conditions FROM ai_course_generation WHERE id = $1`,
      [id],
    );
    expect(row.request_text).toBe('연락은 [전화번호] 로, 산책하고 카페');
    expect(row.counted).toBe(true);
    expect(row.conditions.area).toEqual({
      type: 'point',
      lat: 35.56,
      lng: 128.31,
    });

    // 다른 기기는 볼 수 없다
    const other = await get(device(), id).expect(404);
    expect(body(other).error?.code).toBe('RES_001');

    // 평가 — 결과가 나온 생성만
    const rated = await request(app.getHttpServer())
      .put(`/api/course-generations/${id}/rating`)
      .set(DEVICE_HEADER, me)
      .send({ value: 'like' })
      .expect(200);
    expect(body<GenerationBody>(rated).data.rating).toBe('like');
    const wrongValue = await request(app.getHttpServer())
      .put(`/api/course-generations/${id}/rating`)
      .set(DEVICE_HEADER, me)
      .send({ value: 'love' })
      .expect(400);
    expect(body(wrongValue).error?.code).toBe('VAL_001');
  });

  it('만드는 중이면 AI_004, 취소하면 차감하지 않는다', async () => {
    const me = device();
    ai.mode = 'block';
    const created = await create(me).expect(201);
    const { id } = body<{ id: string }>(created).data;
    await waitFor(me, id, (g) => g.stage === 'planning');

    const second = await create(me).expect(409);
    expect(body(second).error?.code).toBe('AI_004');

    const canceled = await request(app.getHttpServer())
      .post(`/api/course-generations/${id}/cancellation`)
      .set(DEVICE_HEADER, me)
      .expect(200);
    expect(body<GenerationBody>(canceled).data).toMatchObject({
      status: 'canceled',
      remaining: 2,
    });
    // 취소한 생성은 평가할 수 없다
    const rate = await request(app.getHttpServer())
      .put(`/api/course-generations/${id}/rating`)
      .set(DEVICE_HEADER, me)
      .send({ value: 'dislike' })
      .expect(400);
    expect(body(rate).error?.code).toBe('VAL_001');
  });

  it('하루 2번을 다 쓰면 AI_001', async () => {
    const me = device();
    for (let i = 0; i < 2; i++) {
      const { id } = body<{ id: string }>(await create(me).expect(201)).data;
      expect((await waitFor(me, id)).status).toBe('succeeded');
    }
    const third = await create(me).expect(429);
    expect(body(third).error?.code).toBe('AI_001');
  });

  it('조건에 맞는 후보가 없으면 failed + AI_003 이고 차감하지 않는다', async () => {
    const me = device();
    const created = await create(me, {
      area: { type: 'point', ...EMPTY },
    }).expect(201);
    const done = await waitFor(me, body<{ id: string }>(created).data.id);
    expect(done).toMatchObject({
      status: 'failed',
      failure: { code: 'AI_003', notices: [] },
      result: null,
      remaining: 2,
    });
  });

  it('AI 를 쓸 수 없으면 failed + AI_002', async () => {
    const me = device();
    ai.mode = 'unavailable';
    const created = await create(me).expect(201);
    const done = await waitFor(me, body<{ id: string }>(created).data.id);
    expect(done).toMatchObject({
      status: 'failed',
      failure: { code: 'AI_002' },
    });
  });

  it('지난 날짜·짧은 시간·남의 이전 생성은 VAL_001', async () => {
    const me = device();
    const past = await create(me, {
      date: kstDateString(new Date(), -1),
    }).expect(400);
    expect(body(past).error?.code).toBe('VAL_001');
    const short = await create(me, { start: '13:00', end: '14:00' }).expect(
      400,
    );
    expect(body(short).error?.code).toBe('VAL_001');
    const previous = await request(app.getHttpServer())
      .post('/api/course-generations')
      .set(DEVICE_HEADER, me)
      .send({
        request: '',
        conditions: conditions(),
        previousGenerationId: randomUUID(),
      })
      .expect(400);
    expect(body(previous).error?.code).toBe('VAL_001');
  });
});