import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
import request from 'supertest';
import { createHmac } from 'node:crypto';
import app from '../app.js';
import { configureQueue, drain } from '../lib/queue.js';

vi.mock('../db/ingest_events.dao.js', () => ({
  recordDelivery: vi.fn(),
  markProcessing: vi.fn(),
  markDone: vi.fn(),
  markFailed: vi.fn(),
  resetStaleProcessing: vi.fn(),
}));

vi.mock('../db/notes.dao.js', () => ({
  createNotes: vi.fn(),
  getAllNotes: vi.fn(),
  streamAllNotes: vi.fn(),
}));

vi.mock('../lib/httpClient.js', () => ({
  requestJson: vi.fn(),
}));

import {
  recordDelivery,
  markDone,
  markFailed,
  markProcessing,
} from '../db/ingest_events.dao.js';
import { createNotes } from '../db/notes.dao.js';
import { requestJson } from '../lib/httpClient.js';
import { resetSlackCaches } from '../services/slack.service.js';
import type { NoteInput } from '../types/domain.js';

const mockRecordDelivery = vi.mocked(recordDelivery);
const mockCreateNotes = vi.mocked(createNotes);
const mockMarkDone = vi.mocked(markDone);
const mockMarkFailed = vi.mocked(markFailed);
const mockMarkProcessing = vi.mocked(markProcessing);
const mockRequestJson = vi.mocked(requestJson);

const SIGNING_SECRET = 'slack-signing-secret';
const BOT_TOKEN = 'xoxb-test-token';

const reactionEvent = (overrides: Record<string, unknown> = {}): string =>
  JSON.stringify({
    type: 'event_callback',
    event_id: 'Ev0PIN1',
    team_id: 'T999',
    event: {
      type: 'reaction_added',
      user: 'U_REACTOR',
      reaction: 'pushpin',
      item_user: 'U_AUTHOR',
      item: { type: 'message', channel: 'C555', ts: '1700000000.000100' },
      ...overrides,
    },
  });

const sign = (body: string, timestamp: string, secret = SIGNING_SECRET): string =>
  `v0=${createHmac('sha256', secret).update(`v0:${timestamp}:${body}`).digest('hex')}`;

const postEvent = (body: string) => {
  const timestamp = Math.floor(Date.now() / 1000).toString();
  return request(app)
    .post('/v1/webhooks/slack')
    .set('Content-Type', 'application/json')
    .set('x-slack-request-timestamp', timestamp)
    .set('x-slack-signature', sign(body, timestamp))
    .send(body);
};

/** Routes a Slack Web API call by method name to a canned response. */
const slackApi = (responses: Record<string, unknown>): void => {
  mockRequestJson.mockImplementation(async (url: string) => {
    const method = url.split('/api/')[1] ?? '';
    if (!(method in responses)) {
      throw new Error(`Unexpected Slack method: ${method}`);
    }
    return responses[method];
  });
};

const historyWith = (text: string, user = 'U_AUTHOR') => ({
  ok: true,
  messages: [{ text, user, ts: '1700000000.000100' }],
});

const userNamed = (displayName: string) => ({
  ok: true,
  user: { id: 'U_AUTHOR', name: 'fallback', profile: { display_name: displayName } },
});

const notesWritten = (): NoteInput[] => {
  const call = mockCreateNotes.mock.calls[0];
  return call ? call[0] : [];
};

/**
 * Exercises the seam the unit tests cannot: the provider registry wiring that
 * carries a Slack reaction from the signed request through normalization, the
 * ack, the queue, and enrichment into an actual note insert.
 */
describe('Slack reaction capture, end to end', () => {
  const originalSecret = process.env.SLACK_SIGNING_SECRET;
  const originalToken = process.env.SLACK_BOT_TOKEN;
  const originalReaction = process.env.SLACK_CAPTURE_REACTION;

  beforeEach(() => {
    vi.clearAllMocks();
    resetSlackCaches();
    process.env.SLACK_SIGNING_SECRET = SIGNING_SECRET;
    process.env.SLACK_BOT_TOKEN = BOT_TOKEN;
    delete process.env.SLACK_CAPTURE_REACTION;
    configureQueue({ baseDelayMs: 0, maxAttempts: 2 });
    mockRecordDelivery.mockResolvedValue(42);
    mockCreateNotes.mockResolvedValue([]);
  });

  afterEach(async () => {
    await drain();
    const restore = (key: string, value: string | undefined): void => {
      if (value === undefined) delete process.env[key];
      else process.env[key] = value;
    };
    restore('SLACK_SIGNING_SECRET', originalSecret);
    restore('SLACK_BOT_TOKEN', originalToken);
    restore('SLACK_CAPTURE_REACTION', originalReaction);
  });

  it('should turn a pinned message into a note with fetched text and a resolved author', async () => {
    slackApi({
      'conversations.history': historyWith('Deploys are <https://ex.co|scary>'),
      'users.info': userNamed('Jane Doe'),
    });

    const res = await postEvent(reactionEvent());
    expect(res.status).toBe(200);

    await drain();

    const notes = notesWritten();
    expect(notes).toHaveLength(1);
    expect(notes[0].text).toBe('Deploys are scary');
    expect(notes[0].author).toBe('Jane Doe');
    expect(notes[0].sourceMeta).toMatchObject({
      provider: 'slack',
      externalId: 'Ev0PIN1',
      channelId: 'C555',
      authorHandle: 'Jane Doe',
    });
    expect(mockMarkProcessing).toHaveBeenCalledWith(42);
    expect(mockMarkDone).toHaveBeenCalledWith(42);
  });

  /** A placeholder reaching the database would be a visible bug on a sticky. */
  it('should never persist the placeholder text', async () => {
    slackApi({
      'conversations.history': historyWith('real message body'),
      'users.info': userNamed('Jane Doe'),
    });

    await postEvent(reactionEvent());
    await drain();

    expect(notesWritten()[0].text).not.toMatch(/pending/i);
    expect(notesWritten()[0].sourceMeta).not.toHaveProperty('needsMessageText');
  });

  it('should drop the note when the message cannot be fetched', async () => {
    slackApi({
      'conversations.history': { ok: true, messages: [] },
      'conversations.replies': { ok: true, messages: [] },
    });

    await postEvent(reactionEvent());
    await drain();

    expect(notesWritten()).toEqual([]);
    expect(mockMarkDone).toHaveBeenCalledWith(42);
  });

  it('should omit the note count from the ack because enrichment runs after it', async () => {
    slackApi({
      'conversations.history': historyWith('anything'),
      'users.info': userNamed('Jane Doe'),
    });

    const res = await postEvent(reactionEvent());

    expect(res.body).toEqual({ accepted: true });
  });

  it('should ignore a reaction that is not the configured one', async () => {
    const res = await postEvent(reactionEvent({ reaction: 'tada' }));

    expect(res.status).toBe(200);
    await drain();

    expect(mockRequestJson).not.toHaveBeenCalled();
    expect(notesWritten()).toEqual([]);
  });

  it('should honor a custom capture reaction from the environment', async () => {
    process.env.SLACK_CAPTURE_REACTION = 'sticky';
    slackApi({
      'conversations.history': historyWith('captured by custom emoji'),
      'users.info': userNamed('Jane Doe'),
    });

    await postEvent(reactionEvent({ reaction: 'sticky' }));
    await drain();

    expect(notesWritten()[0].text).toBe('captured by custom emoji');
  });

  it('should answer the url_verification handshake', async () => {
    const res = await postEvent(
      JSON.stringify({ type: 'url_verification', challenge: 'abc123' })
    );

    expect(res.status).toBe(200);
    expect(res.body).toEqual({ challenge: 'abc123' });
  });

  it('should reject a delivery whose signature does not match', async () => {
    const body = reactionEvent();
    const timestamp = Math.floor(Date.now() / 1000).toString();

    const res = await request(app)
      .post('/v1/webhooks/slack')
      .set('Content-Type', 'application/json')
      .set('x-slack-request-timestamp', timestamp)
      .set('x-slack-signature', sign(body, timestamp, 'wrong-secret'))
      .send(body);

    expect(res.status).toBe(401);
    expect(mockRecordDelivery).not.toHaveBeenCalled();
  });

  it('should stop at the dedup layer when Slack redelivers an event', async () => {
    mockRecordDelivery.mockResolvedValue(null);

    const res = await postEvent(reactionEvent());

    expect(res.status).toBe(200);
    expect(res.body).toEqual({ duplicate: true });
    await drain();
    expect(mockCreateNotes).not.toHaveBeenCalled();
  });

  /** A failed enrichment must leave the delivery failed, not silently done. */
  it('should mark the delivery failed when the Slack API rejects the fetch', async () => {
    mockRequestJson.mockResolvedValue({ ok: false, error: 'channel_not_found' });

    await postEvent(reactionEvent());
    await drain();

    expect(mockCreateNotes).not.toHaveBeenCalled();
    expect(mockMarkFailed).toHaveBeenCalledWith(42, expect.stringContaining('channel_not_found'));
    expect(mockMarkDone).not.toHaveBeenCalled();
  });

  /** A missing channel is settled; retrying it only delays the queue. */
  it('should not retry a permanent Slack failure', async () => {
    mockRequestJson.mockResolvedValue({ ok: false, error: 'channel_not_found' });

    await postEvent(reactionEvent());
    await drain();

    expect(mockRequestJson).toHaveBeenCalledTimes(1);
  });

  it('should retry a rate-limited Slack failure until the attempt cap', async () => {
    mockRequestJson.mockResolvedValue({ ok: false, error: 'ratelimited' });

    await postEvent(reactionEvent());
    await drain();

    expect(mockRequestJson).toHaveBeenCalledTimes(2);
  });
});