import http from 'http';
import { AddressInfo } from 'net';
import { promises as fsp } from 'fs';
import os from 'os';
import path from 'path';
import { pool } from '../../src/db';
import { resetDb, closeDb } from './setup/testDb';
import { draftQueued } from '../../src/intake/draftingWorker';
import { resetAnthropicClient } from '../../src/intake/anthropicClient';
import { draftListing } from '../../src/intake/draftListing';
import { restoreImageOriginal } from '../../src/intake/backgroundRemoval';

/**
 * The worker's background-removal step (#281).
 *
 * The model is mocked rather than reached. What is under test is what the
 * worker does *after* a draft is written — which of the two paths it takes,
 * and what survives when the sidecar does not answer — and none of that
 * depends on what the model said.
 */
jest.mock('../../src/intake/draftListing');

const draftListingMock = draftListing as jest.MockedFunction<typeof draftListing>;

const JPEG_BYTES = Buffer.from([0xff, 0xd8, 0xff, 0xe0, 0, 0, 0, 0, 0, 0, 0, 0]);
const PNG_BYTES = Buffer.from([0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a, 0, 0, 0, 0]);

let uploads = '';
let stub: http.Server | null = null;
let previousUploadsDir: string | undefined;

beforeEach(async () => {
  await resetDb();

  draftListingMock.mockResolvedValue({
    draft: {
      name: 'Blue stoneware vase',
      description: 'Hand-thrown, chipped base.',
      category: null,
      tags: [],
      suggestedPriceCents: 4500
    },
    model: 'claude-sonnet-5',
    inputTokens: 1000,
    outputTokens: 200,
    costMicros: 4000
  });

  // Non-empty is all that is needed: getAnthropicClient only has to return
  // something other than null, and the mock above is what answers.
  process.env.ANTHROPIC_API_KEY = 'sk-ant-not-used';
  resetAnthropicClient();

  uploads = await fsp.mkdtemp(path.join(os.tmpdir(), 'workerbg-'));
  previousUploadsDir = process.env.UPLOADS_DIR;
  process.env.UPLOADS_DIR = uploads;

  stub = http.createServer((req, res) => {
    req.on('data', () => undefined);
    req.on('end', () => {
      res.writeHead(200, { 'Content-Type': 'image/png' });
      res.end(PNG_BYTES);
    });
  });
  await new Promise<void>((resolve) => stub!.listen(0, '127.0.0.1', resolve));
  process.env.REMBG_URL = `http://127.0.0.1:${(stub!.address() as AddressInfo).port}`;
});

afterEach(async () => {
  delete process.env.REMBG_URL;
  delete process.env.ANTHROPIC_API_KEY;
  resetAnthropicClient();
  if (stub) {
    await new Promise<void>((resolve) => stub!.close(() => resolve()));
    stub = null;
  }
  if (uploads !== '') {
    await fsp.rm(uploads, { recursive: true, force: true });
    uploads = '';
  }
  if (previousUploadsDir === undefined) delete process.env.UPLOADS_DIR;
  else process.env.UPLOADS_DIR = previousUploadsDir;
  previousUploadsDir = undefined;
});

afterAll(async () => {
  await pool.end();
  await closeDb();
});

/** A queued submission with one real file on disk and the intent set. */
async function seedSubmissionWithPhoto(options: { removeBackground: boolean }): Promise<number> {
  const { rows } = await pool.query<{ id: number }>(
    `INSERT INTO items (name, status) VALUES ('Submission placeholder', 'pending') RETURNING id`
  );
  const itemId = rows[0]!.id;
  await pool.query(
    `INSERT INTO item_drafts (item_id, submitter_note, remove_background)
     VALUES ($1, 'a note', $2)`,
    [itemId, options.removeBackground]
  );
  await pool.query(
    `INSERT INTO item_images (item_id, image_path, sort_order)
     VALUES ($1, '/uploads/worker.jpg', 0)`,
    [itemId]
  );
  await fsp.writeFile(path.join(uploads, 'worker.jpg'), JPEG_BYTES);
  return itemId;
}

async function originalPathOf(itemId: number): Promise<string | null> {
  const { rows } = await pool.query<{ original_image_path: string | null }>(
    `SELECT original_image_path FROM item_images WHERE item_id = $1`,
    [itemId]
  );
  return rows[0]?.original_image_path ?? null;
}

describe('background removal after a draft', () => {
  // The mock has to actually be in play, or the two cases below would both
  // pass for the wrong reason — a draft that never happened cuts nothing out.
  it('drafts successfully, which is what the removal step follows', async () => {
    await seedSubmissionWithPhoto({ removeBackground: false });

    expect(await draftQueued(1)).toEqual({ drafted: 1, failed: 0, skipped: 0 });
  });

  // Recorded at submission and acted on here, so the sender never waits and a
  // sidecar that is down cannot fail their upload.
  it('cuts out the photos when the submitter asked for it', async () => {
    const itemId = await seedSubmissionWithPhoto({ removeBackground: true });

    await draftQueued(1);

    expect(await originalPathOf(itemId)).toBe('/uploads/worker.jpg');
  });

  it('leaves the photos alone when they did not', async () => {
    const itemId = await seedSubmissionWithPhoto({ removeBackground: false });

    await draftQueued(1);

    expect(await originalPathOf(itemId)).toBeNull();
  });

  // The governing rule: removal is a convenience on top of a draft that was
  // written correctly. A sidecar failure must never turn a good draft into a
  // failed one, because the queue is what the admin actually works from.
  it('leaves the draft ready when the sidecar fails', async () => {
    const itemId = await seedSubmissionWithPhoto({ removeBackground: true });
    // Configured, and nothing listening on it.
    process.env.REMBG_URL = 'http://127.0.0.1:1';

    await draftQueued(1);

    const { rows } = await pool.query<{ state: string }>(
      `SELECT state FROM item_drafts WHERE item_id = $1`,
      [itemId]
    );
    expect(rows[0]?.state).toBe('ready');
    expect(await originalPathOf(itemId)).toBeNull();
  });

  // The bug this closes: remove_background is written once at intake and
  // otherwise never updated, so a restored photo used to look identical to
  // one that was simply never cut out — and Regenerate would read the same
  // stale `true` and cut it out again, quietly undoing what the admin just
  // did. restoreImageOriginal now clears the flag as part of the restore
  // itself, so the worker respects the admin's decision on the next pass.
  it('does not re-cut a photo the admin restored, even after Regenerate', async () => {
    const itemId = await seedSubmissionWithPhoto({ removeBackground: true });
    await draftQueued(1);
    expect(await originalPathOf(itemId)).toBe('/uploads/worker.jpg');

    const { rows: imageRows } = await pool.query<{ id: number }>(
      `SELECT id FROM item_images WHERE item_id = $1`,
      [itemId]
    );
    await restoreImageOriginal(imageRows[0]!.id);

    const { rows: flagRows } = await pool.query<{ remove_background: boolean }>(
      `SELECT remove_background FROM item_drafts WHERE item_id = $1`,
      [itemId]
    );
    expect(flagRows[0]?.remove_background).toBe(false);

    // Mirrors what the admin's Regenerate button does: back to queued, with
    // attempts cleared, so the worker picks the item up again.
    await pool.query(
      `UPDATE item_drafts SET state = 'queued', attempts = 0, ai_error = NULL WHERE item_id = $1`,
      [itemId]
    );

    await draftQueued(1);

    expect(await originalPathOf(itemId)).toBeNull();
  });
});