const IDLE_MIN_MS = 2000;
const IDLE_MAX_MS = 60000;
const REQUEST_TIMEOUT_MS = parseInt(process.env.AI_REQUEST_TIMEOUT_MS || '120000', 10);
const MAX_INPUT_CHARS = 2000;
const MIN_TEXT_CHARS = 4;
const crypto = require('crypto');
const { textDiff, FIELD_LABELS } = require('./diff');
const PHOTO_MAX_ATTEMPTS = 3;
const PHOTO_AI_TIMEOUT_MS = Math.max(1000, parseInt(process.env.PHOTO_AI_TIMEOUT_MS || '300000', 10) || 300000);
const PHOTO_AI_FACE_TIMEOUT_MS = Math.max(PHOTO_AI_TIMEOUT_MS, parseInt(process.env.PHOTO_AI_FACE_TIMEOUT_MS || '600000', 10) || 600000);
const PHOTO_AI_DEFAULT_MODEL = 'x2plus';
const PHOTO_AI_DEFAULT_FACE_MODEL = String(process.env.PHOTO_AI_FACE_MODEL || 'gfpgan').trim() || 'gfpgan';
const PHOTO_AI_DEFAULT_STRENGTH = 0.7;
const PHOTO_AI_ACTIONS = new Set(['ai', 'ai_face', 'ai_upscale']);
const PHOTO_SOFT_MAX_RETRIES = Math.max(1, parseInt(process.env.PHOTO_AI_SOFT_MAX_RETRIES || '60', 10) || 60);
const PHOTO_SOFT_BACKOFF_MS = Math.max(1000, parseInt(process.env.PHOTO_AI_SOFT_BACKOFF_MS || '10000', 10) || 10000);
const PHOTO_SOFT_BACKOFF_MAX_MS = Math.max(PHOTO_SOFT_BACKOFF_MS, parseInt(process.env.PHOTO_AI_SOFT_BACKOFF_MAX_MS || '300000', 10) || 300000);

function isTimeoutFailure(e) {
  const name = e && e.name;
  return name === 'TimeoutError' || name === 'AbortError';
}

function isSoftStatus(status) {
  return status === 408 || status === 425 || status === 429 || status >= 500;
}

function failureReason(e) {
  const parts = [];
  let cur = e;
  for (let i = 0; cur && i < 5; i++) {
    const code = cur.code || (cur.errors && cur.errors.code);
    if (code && !parts.includes(code)) parts.push(code);
    cur = cur.cause;
  }
  return parts.join(', ');
}

function softFailure(message, e) {
  const reason = e ? failureReason(e) || (e.message || '') : '';
  const err = new Error(reason ? `${message} (${reason})` : message);
  err.soft = true;
  return err;
}

function createPhotoEnhanceWorker({ pool, getSetting, logAudit, invalidateEntries, sharp, photoAiUrl, storage, bus, notifyEvent, faceTimeoutMs, defaultModel, defaultFaceModel }) {
  const AI_URL = photoAiUrl || process.env.PHOTO_AI_URL || '';
  const IDLE_MIN = 2000;
  const IDLE_MAX = 30000;
  const AI_TIMEOUT_MS = PHOTO_AI_TIMEOUT_MS;
  const AI_FACE_TIMEOUT_MS = Math.max(AI_TIMEOUT_MS, parseInt(faceTimeoutMs, 10) || PHOTO_AI_FACE_TIMEOUT_MS);
  const DEFAULT_MODEL = String(defaultModel || PHOTO_AI_DEFAULT_MODEL).trim() || PHOTO_AI_DEFAULT_MODEL;
  const DEFAULT_FACE_MODEL = String(defaultFaceModel || PHOTO_AI_DEFAULT_FACE_MODEL).trim() || PHOTO_AI_DEFAULT_FACE_MODEL;

  async function sendNotification(entryId, payload) {
    if (!notifyEvent) return;
    try {
      await notifyEvent(entryId, payload);
    } catch (e) {
      console.error('Photo worker notification failed:', e.message);
    }
  }

  let started = false;
  let stopped = false;
  let idleMs = IDLE_MIN;
  let wake = null;
  let processing = false;
  let currentId = null;
  let startedAt = null;
  const stats = { jobs: 0, done: 0, errors: 0, soft_retries: 0, last_at: null, last_error: null };
  const softTries = new Map();
  const CONFIG = {
    idle_min_ms: IDLE_MIN,
    idle_max_ms: IDLE_MAX,
    ai_timeout_ms: AI_TIMEOUT_MS,
    face_timeout_ms: AI_FACE_TIMEOUT_MS,
    max_attempts: PHOTO_MAX_ATTEMPTS,
    soft_max_retries: PHOTO_SOFT_MAX_RETRIES,
    soft_backoff_ms: PHOTO_SOFT_BACKOFF_MS,
    soft_backoff_max_ms: PHOTO_SOFT_BACKOFF_MAX_MS,
    ai_url: AI_URL,
    default_model: DEFAULT_MODEL,
    face_model: DEFAULT_FACE_MODEL,
  };

  function sleep(ms) {
    return new Promise((resolve) => {
      const t = setTimeout(() => { wake = null; resolve(); }, ms);
      wake = () => { clearTimeout(t); wake = null; resolve(); };
    });
  }

  function wakeLocal() {
    if (wake) wake();
  }

  function notify() {
    wakeLocal();
    if (bus) bus.publish();
  }

  if (bus) bus.subscribe(wakeLocal);

  async function isEnabled() {
    const v = await getSetting('photo_worker_enabled', 'true');
    return String(v) !== 'false';
  }

  async function claimNext() {
    const client = await pool.connect();
    try {
      await client.query('BEGIN');
      const { rows } = await client.query(
        `SELECT j.id, j.entry_id, j.action, j.params
         FROM photo_jobs j
         WHERE j.status = 'pending'
         ORDER BY j.id ASC LIMIT 1 FOR UPDATE SKIP LOCKED`
      );
      if (!rows.length) {
        await client.query('COMMIT');
        return null;
      }
      await client.query(`UPDATE photo_jobs SET status = 'processing' WHERE id = $1`, [rows[0].id]);
      await client.query('COMMIT');
      return rows[0];
    } catch (e) {
      await client.query('ROLLBACK').catch(() => {});
      throw e;
    } finally {
      client.release();
    }
  }

  async function enhanceWithSharp(srcKey, params) {
    if (!sharp) throw new Error('sharp недоступен на сервере');
    const p = params || {};
    const clamp = (v, min, max, def) => {
      const n = parseFloat(v);
      return Number.isFinite(n) ? Math.min(max, Math.max(min, n)) : def;
    };
    const brightness = clamp(p.brightness, 10, 300, 100);
    const contrast = clamp(p.contrast, 10, 300, 100);
    const saturate = clamp(p.saturate, 0, 300, 100);
    const sharpAmt = clamp(p.sharp, 0, 100, 0);
    const denoise = clamp(p.denoise, 0, 100, 0);
    const srcPath = await storage.localize(srcKey);
    if (!srcPath) throw new Error('Файл фото не найден');
    let pipeline = sharp(srcPath).rotate();
    if (denoise > 0) pipeline = pipeline.median(denoise > 70 ? 5 : 3);
    pipeline = pipeline.modulate({ brightness: brightness / 100, saturation: saturate / 100 });
    if (contrast !== 100) {
      const a = contrast / 100;
      pipeline = pipeline.linear(a, 128 * (1 - a));
    }
    if (sharpAmt > 0) {
      pipeline = pipeline.sharpen({ sigma: 0.5 + (sharpAmt / 100) * 1.5, m1: 0, m2: 1 + sharpAmt / 50 });
    }
    const newName = crypto.randomBytes(12).toString('hex') + '.jpg';
    const out = await pipeline.jpeg({ quality: 92, mozjpeg: true }).toBuffer();
    await storage.put(newName, out);
    return `/uploads/${newName}`;
  }

  function aiParams(job) {
    const p = job && job.params && typeof job.params === 'object' ? job.params : {};
    const face = String(p.face || (job && job.action === 'ai_face' ? 'face' : 'off')).trim().toLowerCase() || 'off';
    const strength = Number(p.strength);
    return {
      model: String(p.model || DEFAULT_MODEL).trim().toLowerCase() || DEFAULT_MODEL,
      face,
      face_model: String(p.face_model || DEFAULT_FACE_MODEL).trim().toLowerCase() || DEFAULT_FACE_MODEL,
      strength: Number.isFinite(strength) ? strength : PHOTO_AI_DEFAULT_STRENGTH,
      timeout_ms: face === 'off' ? AI_TIMEOUT_MS : AI_FACE_TIMEOUT_MS,
    };
  }

  function aiMeta(source) {
    const o = source && typeof source === 'object' ? source : {};
    const num = (v) => (Number.isFinite(Number(v)) && v !== null && v !== '' ? Number(v) : null);
    return {
      model: o.model ? String(o.model) : null,
      face: o.face ? String(o.face) : null,
      face_model: o.face_model ? String(o.face_model) : null,
      faces_found: num(o.faces_found),
      device: o.device ? String(o.device) : null,
      elapsed_ms: num(o.elapsed_ms),
      warnings: Array.isArray(o.warnings) ? o.warnings.map((w) => String(w).slice(0, 300)).slice(0, 5) : [],
    };
  }

  async function readErrorBody(resp) {
    try {
      const text = (await resp.text()).trim();
      if (!text) return null;
      let data = null;
      try { data = JSON.parse(text); } catch (e) {}
      if (data && typeof data === 'object' && !Array.isArray(data)) {
        return String(data.error || data.detail || '').slice(0, 400) || null;
      }
      return text.slice(0, 400);
    } catch (e) {
      return null;
    }
  }

  async function runAiEnhance(srcKey, job) {
    if (!AI_URL) throw new Error('PHOTO_AI_URL не настроен');
    const opt = aiParams(job);
    const buf = await storage.getBuffer(srcKey);
    if (!buf) throw new Error('Файл фото не найден');
    const fd = new FormData();
    fd.append('image', new Blob([buf], { type: 'image/jpeg' }), 'photo.jpg');
    fd.append('scale', '2');
    fd.append('model', opt.model);
    fd.append('face', opt.face);
    fd.append('face_model', opt.face_model);
    fd.append('strength', String(opt.strength));
    let resp;
    try {
      resp = await fetch(AI_URL.replace(/\/+$/, '') + '/enhance', {
        method: 'POST',
        headers: { Accept: 'application/json' },
        body: fd,
        signal: AbortSignal.timeout(opt.timeout_ms),
      });
    } catch (e) {
      if (isTimeoutFailure(e)) {
        throw new Error(`ИИ-сервис не ответил за ${Math.round(opt.timeout_ms / 1000)} с`);
      }
      throw softFailure('ИИ-сервис недоступен', e);
    }
    if (!resp.ok) {
      const retryAfter = resp.headers.get('retry-after');
      const detail = `ИИ-сервис ответил ${resp.status}${retryAfter ? ` (Retry-After: ${retryAfter})` : ''}`;
      const reason = await readErrorBody(resp);
      const message = reason ? `${detail}: ${reason}` : detail;
      if (isSoftStatus(resp.status)) throw softFailure(message);
      throw new Error(message);
    }
    const contentType = resp.headers.get('content-type') || '';
    if (!contentType.includes('application/json')) {
      const out = Buffer.from(await resp.arrayBuffer());
      return {
        out,
        meta: aiMeta({
          model: resp.headers.get('x-photo-ai-model') || opt.model,
          face: resp.headers.get('x-photo-ai-face') || opt.face,
          face_model: opt.face === 'off' ? null : opt.face_model,
          device: resp.headers.get('x-photo-ai-device'),
          elapsed_ms: resp.headers.get('x-photo-ai-elapsed-ms'),
        }),
      };
    }
    let data;
    try {
      data = await resp.json();
    } catch (e) {
      throw new Error('ИИ-сервис вернул нечитаемый JSON');
    }
    if (!data || typeof data !== 'object' || Array.isArray(data)) throw new Error('ИИ-сервис вернул неожиданный JSON');
    if (data.ok === false) throw new Error(String(data.error || 'ИИ-сервис вернул ошибку').slice(0, 500));
    if (typeof data.image_base64 !== 'string' || !data.image_base64) throw new Error('ИИ-сервис не вернул изображение');
    let out;
    try {
      out = Buffer.from(data.image_base64, 'base64');
    } catch (e) {
      throw new Error('ИИ-сервис вернул изображение в нечитаемом base64');
    }
    if (!out.length) throw new Error('ИИ-сервис вернул пустое изображение');
    return {
      out,
      meta: aiMeta({
        model: data.model || opt.model,
        face: data.face || opt.face,
        face_model: data.face_model || (opt.face === 'off' ? null : opt.face_model),
        faces_found: data.faces_found,
        device: data.device,
        elapsed_ms: data.elapsed_ms,
        warnings: data.warnings,
      }),
    };
  }

  async function enhanceWithAi(srcKey, job) {
    const { out, meta } = await runAiEnhance(srcKey, job);
    const newName = crypto.randomBytes(12).toString('hex') + '.jpg';
    await storage.put(newName, out);
    return { path: `/uploads/${newName}`, meta };
  }

  async function applyResult(job, newPath, meta) {
    const m = meta || {};
    await pool.query(
      `UPDATE photo_jobs SET status = 'done', after_path = $1, error = NULL, finished_at = now() WHERE id = $2`,
      [newPath, job.id]
    );
    if (logAudit) {
      await logAudit(null, 'photo.job.preview', {
        entry_id: job.entry_id,
        job_id: job.id,
        action: job.action,
        after_path: newPath,
        model: m.model,
        face: m.face,
        face_model: m.face_model,
        device: m.device,
        faces_found: m.faces_found,
        elapsed_ms: m.elapsed_ms,
        warnings: m.warnings && m.warnings.length ? m.warnings : null,
      });
    }
    const title = job.action === 'ai_face'
      ? 'Фото обработано нейросетью с восстановлением лиц: {student}'
      : job.action === 'ai_upscale'
        ? 'Фото обработано нейросетью (апскейл): {student}'
        : job.action === 'ai'
          ? 'Фото обработано нейросетью: {student}'
          : 'Фото улучшено на сервере: {student}';
    const warn = m.warnings && m.warnings.length ? ' · ' + m.warnings.join('; ').slice(0, 300) : '';
    await sendNotification(job.entry_id, {
      type: 'photo.job.done',
      title,
      body: `Группа {group} · запись #${job.entry_id} · результат ждёт применения${warn}`,
      target: {
        job_id: job.id,
        action: job.action,
        after_path: newPath,
        model: m.model,
        face: m.face,
        face_model: m.face_model,
        device: m.device,
        faces_found: m.faces_found,
        elapsed_ms: m.elapsed_ms,
      },
    });
  }
  async function softRetry(job, message) {
    const n = (softTries.get(job.id) || 0) + 1;
    if (n <= PHOTO_SOFT_MAX_RETRIES) {
      softTries.set(job.id, n);
      stats.soft_retries++;
      await pool.query(`UPDATE photo_jobs SET status = 'pending', error = $1 WHERE id = $2`, [message, job.id]);
      if (logAudit && (n === 1 || n % 10 === 0)) {
        await logAudit(null, 'photo.job.soft_retry', {
          entry_id: job.entry_id,
          job_id: job.id,
          soft_attempt: n,
          soft_limit: PHOTO_SOFT_MAX_RETRIES,
          error: message,
        });
      }
      const delay = Math.min(PHOTO_SOFT_BACKOFF_MS * Math.pow(2, n - 1), PHOTO_SOFT_BACKOFF_MAX_MS);
      return { ok: false, delay };
    }
    softTries.delete(job.id);
    const text = `${message} — ИИ-сервис недоступен, мягкие повторы исчерпаны (${PHOTO_SOFT_MAX_RETRIES}), задание остановлено`;
    await pool.query(
      `UPDATE photo_jobs SET status = 'error', error = $1, finished_at = now() WHERE id = $2`,
      [text, job.id]
    );
    stats.errors++;
    stats.last_error = text;
    if (logAudit) {
      await logAudit(null, 'photo.job.error', { entry_id: job.entry_id, job_id: job.id, error: text, soft_attempts: PHOTO_SOFT_MAX_RETRIES });
    }
    await sendNotification(job.entry_id, {
      type: 'photo.job.error',
      title: 'Ошибка обработки фото: {student}',
      body: `Группа {group} · запись #${job.entry_id} · ${text}`,
      target: { job_id: job.id, action: job.action, error: text },
    });
    return { ok: true, delay: 0 };
  }

  async function processOne(job) {
    stats.jobs++;
    const { rows } = await pool.query('SELECT photo_path FROM entries WHERE id = $1', [job.entry_id]);
    if (!rows.length || !rows[0].photo_path) {
      await pool.query(
        `UPDATE photo_jobs SET status = 'error', error = 'У записи нет фото', finished_at = now() WHERE id = $1`,
        [job.id]
      );
      stats.errors++;
      stats.last_at = new Date().toISOString();
      stats.last_error = 'У записи нет фото';
      await sendNotification(job.entry_id, {
        type: 'photo.job.error',
        title: 'Ошибка обработки фото: {student}',
        body: `Группа {group} · запись #${job.entry_id} · у записи нет фото для обработки`,
        target: { job_id: job.id, action: job.action },
      });
      return { ok: true, delay: 0 };
    }
    const photoPath = rows[0].photo_path;
    try {
      const result = PHOTO_AI_ACTIONS.has(job.action)
        ? await enhanceWithAi(photoPath, job)
        : { path: await enhanceWithSharp(photoPath, job.params), meta: null };
      await applyResult(job, result.path, result.meta);
      softTries.delete(job.id);
      stats.done++;
      stats.last_at = new Date().toISOString();
      stats.last_error = null;
      return { ok: true, delay: 0 };
    } catch (e) {
      const message = (e && e.message ? e.message : 'error').slice(0, 500);
      stats.last_at = new Date().toISOString();
      stats.last_error = message;
      if (e && e.soft) return await softRetry(job, message);
      const { rows: cur } = await pool.query('SELECT attempts FROM photo_jobs WHERE id = $1', [job.id]);
      const tries = ((cur[0] && cur[0].attempts) || 0) + 1;
      if (tries < PHOTO_MAX_ATTEMPTS) {
        await pool.query(`UPDATE photo_jobs SET status = 'pending', attempts = $1, error = $2 WHERE id = $3`, [tries, message, job.id]);
        if (logAudit) await logAudit(null, 'photo.job.retry', { entry_id: job.entry_id, job_id: job.id, attempt: tries, error: message });
        return { ok: false, delay: 0 };
      }
      softTries.delete(job.id);
      await pool.query(
        `UPDATE photo_jobs SET status = 'error', attempts = $1, error = $2, finished_at = now() WHERE id = $3`,
        [tries, message, job.id]
      );
      stats.errors++;
      if (logAudit) await logAudit(null, 'photo.job.error', { entry_id: job.entry_id, job_id: job.id, error: message });
      await sendNotification(job.entry_id, {
        type: 'photo.job.error',
        title: 'Ошибка обработки фото: {student}',
        body: `Группа {group} · запись #${job.entry_id} · ${message}`,
        target: { job_id: job.id, action: job.action, error: message },
      });
      return { ok: true, delay: 0 };
    }
  }

  async function loop() {
    while (!stopped) {
      let job = null;
      try {
        if (!(await isEnabled())) {
          await sleep(IDLE_MAX);
          continue;
        }
        job = await claimNext();
      } catch (e) {
        console.error('Photo worker claim error:', e);
        await sleep(IDLE_MAX);
        continue;
      }
      if (!job) {
        await sleep(idleMs);
        idleMs = Math.min(idleMs * 2, IDLE_MAX);
        continue;
      }
      idleMs = IDLE_MIN;
      processing = true;
      currentId = job.id;
      let res = { ok: true, delay: 0 };
      try {
        res = await processOne(job);
      } catch (e) {
        console.error('Photo worker process error:', e);
      } finally {
        processing = false;
        currentId = null;
      }
      if (!res || !res.ok) await sleep((res && res.delay) || IDLE_MAX);
    }
  }

  async function resetStale() {
    await pool.query(`UPDATE photo_jobs SET status = 'pending' WHERE status = 'processing'`);
  }

  function start() {
    if (started) return;
    started = true;
    startedAt = Date.now();
    resetStale()
      .catch((e) => console.error('Photo worker reset error:', e))
      .finally(() => { loop().catch((e) => console.error('Photo worker loop error:', e)); });
  }

  function getInfo() {
    return {
      started_at: startedAt ? new Date(startedAt).toISOString() : null,
      uptime_ms: startedAt ? Date.now() - startedAt : 0,
      processing,
      current_id: currentId,
      config: CONFIG,
      ...stats,
    };
  }

  return { start, notify, getInfo };
}

function createEntryAutoChecker({ pool, getSetting, logAudit, aiUrl, defaultPrompt, model, bus }) {
  const AI_URL = aiUrl || process.env.AI_URL || 'http://text-corrector:8080';
  const MODEL = model || process.env.AI_MODEL || 'qwen2.5-1.5b-instruct-q4_k_m.gguf';
  const DEFAULT_PROMPT = defaultPrompt || process.env.AI_PROMPT || 'Ты — редактор текстов. Исправь ТОЛЬКО грамматические, орфографические и пунктуационные ошибки в тексте. Приведи к правильному регистру буквы. НЕ меняй слова, структуру предложений, стиль или смысл текста. Верни ТОЛЬКО исправленный текст без пояснений.';

  let started = false;
  let stopped = false;
  let idleMs = IDLE_MIN_MS;
  let wake = null;
  let processing = false;
  let currentId = null;
  let startedAt = null;
  const stats = { checks: 0, corrected: 0, unchanged: 0, errors: 0, last_at: null, last_error: null };
  const attempts = new Map();
  const MAX_ATTEMPTS = 3;
  const CONFIG = {
    idle_min_ms: IDLE_MIN_MS,
    idle_max_ms: IDLE_MAX_MS,
    request_timeout_ms: REQUEST_TIMEOUT_MS,
    max_input_chars: MAX_INPUT_CHARS,
    min_text_chars: MIN_TEXT_CHARS,
    max_attempts: MAX_ATTEMPTS,
    model: MODEL,
    ai_url: AI_URL,
  };

  function sleep(ms) {
    return new Promise((resolve) => {
      const t = setTimeout(() => { wake = null; resolve(); }, ms);
      wake = () => { clearTimeout(t); wake = null; resolve(); };
    });
  }

  function wakeLocal() {
    if (wake) wake();
  }

  function notify() {
    wakeLocal();
    if (bus) bus.publish();
  }

  if (bus) bus.subscribe(wakeLocal);

  async function isEnabled() {
    const v = await getSetting('ai_autocheck_enabled', 'true');
    return String(v) !== 'false';
  }

  async function claimNext() {
    const client = await pool.connect();
    try {
      await client.query('BEGIN');
      const { rows } = await client.query(
        `SELECT id, description, description_original FROM entries
         WHERE ai_status = 'pending' AND deleted_at IS NULL
         ORDER BY id ASC LIMIT 1 FOR UPDATE SKIP LOCKED`
      );
      if (!rows.length) {
        await client.query('COMMIT');
        return null;
      }
      await client.query(`UPDATE entries SET ai_status = 'processing' WHERE id = $1`, [rows[0].id]);
      await client.query('COMMIT');
      return rows[0];
    } catch (e) {
      await client.query('ROLLBACK').catch(() => {});
      throw e;
    } finally {
      client.release();
    }
  }

  async function resolveActiveProfile() {
    try {
      const active = await getSetting('ai_active_profile', 'native');
      if (active && active !== 'native') {
        const raw = await getSetting('ai_profiles', '[]');
        const list = JSON.parse(raw || '[]');
        if (Array.isArray(list)) {
          return list.find(p => p && p.id === active && p.base_url && p.model) || null;
        }
      }
    } catch (e) {}
    return null;
  }

  function normalizeOpenAiBase(base) {
    let b = String(base || '').trim().replace(/\/+$/, '');
    if (!/^https?:\/\//i.test(b)) return null;
    if (!/\/v1$/i.test(b)) b += '/v1';
    return b;
  }

  async function callModel(text, systemPrompt) {
    const profile = await resolveActiveProfile();
    const headers = { 'Content-Type': 'application/json' };
    let url;
    let model;
    let maxTokens;
    if (profile) {
      const base = normalizeOpenAiBase(profile.base_url);
      if (!base) throw new Error('Некорректный base_url профиля ИИ');
      url = `${base}/chat/completions`;
      model = profile.model;
      if (profile.api_key) headers.Authorization = `Bearer ${profile.api_key}`;
      maxTokens = parseInt(profile.max_tokens, 10) || Math.min(4096, Math.max(1024, text.length * 2 + 512));
    } else {
      url = `${AI_URL.replace(/\/+$/, '')}/v1/chat/completions`;
      model = MODEL;
      maxTokens = Math.min(256, Math.max(128, text.length + 64));
    }
    const controller = new AbortController();
    const timer = setTimeout(() => controller.abort(), REQUEST_TIMEOUT_MS);
    try {
      const res = await fetch(url, {
        method: 'POST',
        headers,
        signal: controller.signal,
        body: JSON.stringify({
          model,
          messages: [
            { role: 'system', content: systemPrompt },
            { role: 'user', content: text },
          ],
          temperature: 0.1,
          max_tokens: maxTokens,
        }),
      });
      if (!res.ok) throw new Error(`AI service error: ${res.status}`);
      const data = await res.json();
      const choice = data.choices && data.choices[0];
      const content = (choice && choice.message && choice.message.content || '').trim();
      if (!content) {
        throw new Error(`Модель вернула пустой ответ (finish_reason=${choice && choice.finish_reason || 'unknown'})`);
      }
      return content;
    } finally {
      clearTimeout(timer);
    }
  }

  function sanitize(original, out) {
    if (!out) return original;
    const o = out.trim();
    if (!o) return original;
    if (o.length > original.length * 4 + 80) return original;
    return o;
  }

  async function processOne(row) {
    const original = String(row.description_original ?? row.description ?? '').trim();
    if (original.length < MIN_TEXT_CHARS) {
      await pool.query(`UPDATE entries SET ai_status = 'skipped', ai_checked_at = now() WHERE id = $1`, [row.id]);
      return true;
    }
    const prompt = (await getSetting('ai_prompt', DEFAULT_PROMPT)) || DEFAULT_PROMPT;
    const input = original.length > MAX_INPUT_CHARS ? original.slice(0, MAX_INPUT_CHARS) : original;
    try {
      const out = await callModel(input, prompt);
      const checked = sanitize(input, out);
      const changed = checked !== input;
      await pool.query(
        `UPDATE entries SET description_ai = $1, description = $1, ai_status = 'done', ai_error = NULL, ai_checked_at = now() WHERE id = $2`,
        [changed ? checked : original, row.id]
      );
      attempts.delete(row.id);
      stats.checks++;
      if (changed) stats.corrected++; else stats.unchanged++;
      stats.last_at = new Date().toISOString();
      stats.last_error = null;
      if (logAudit) {
        const d = textDiff(String(row.description ?? ''), changed ? checked : original);
        await logAudit(null, 'entry.ai.auto-check', {
          id: row.id,
          source: 'ai',
          changed,
          fields: changed ? ['description'] : [],
          changes: changed
            ? [{ field: 'description', label: FIELD_LABELS.description, stats: d.stats, diff: d.segments, truncated: d.truncated }]
            : []
        });
      }
      return true;
    } catch (e) {
      const message = (e && e.message ? e.message : 'error').slice(0, 500);
      const tries = (attempts.get(row.id) || 0) + 1;
      stats.last_at = new Date().toISOString();
      stats.last_error = message;
      if (tries < MAX_ATTEMPTS) {
        attempts.set(row.id, tries);
        await pool.query(`UPDATE entries SET ai_status = 'pending', ai_error = $1 WHERE id = $2`, [message, row.id]);
        if (logAudit) await logAudit(null, 'entry.ai.retry', { id: row.id, attempt: tries, error: message });
        return false;
      }
      attempts.delete(row.id);
      stats.errors++;
      await pool.query(
        `UPDATE entries SET ai_status = 'error', ai_error = $1, ai_checked_at = now() WHERE id = $2`,
        [message, row.id]
      );
      if (logAudit) await logAudit(null, 'entry.ai.error', { id: row.id, error: message });
      return true;
    }
  }

  async function loop() {
    while (!stopped) {
      let row = null;
      try {
        if (!(await isEnabled())) {
          await sleep(IDLE_MAX_MS);
          continue;
        }
        row = await claimNext();
      } catch (e) {
        console.error('AI auto-check claim error:', e);
        await sleep(IDLE_MAX_MS);
        continue;
      }
      if (!row) {
        await sleep(idleMs);
        idleMs = Math.min(idleMs * 2, IDLE_MAX_MS);
        continue;
      }
      idleMs = IDLE_MIN_MS;
      processing = true;
      currentId = row.id;
      let ok = true;
      try {
        ok = await processOne(row);
      } catch (e) {
        console.error('AI auto-check process error:', e);
      } finally {
        processing = false;
        currentId = null;
      }
      if (!ok) await sleep(IDLE_MAX_MS);
    }
  }

  async function resetStale() {
    await pool.query(`UPDATE entries SET ai_status = 'pending' WHERE ai_status = 'processing'`);
  }

  function start() {
    if (started) return;
    started = true;
    startedAt = Date.now();
    resetStale()
      .catch((e) => console.error('AI auto-check reset error:', e))
      .finally(() => { loop().catch((e) => console.error('AI auto-check loop error:', e)); });
  }

  function getStats() {
    return { ...stats, processing };
  }

  function getInfo() {
    return {
      started_at: startedAt ? new Date(startedAt).toISOString() : null,
      uptime_ms: startedAt ? Date.now() - startedAt : 0,
      processing,
      current_id: currentId,
      config: CONFIG,
      ...stats,
    };
  }

  return { start, notify, getStats, getInfo };
}

function createLessonReportChecker({ pool, getSetting, logAudit, aiUrl, model, defaultPrompt, bus, onDone }) {
  const AI_URL = aiUrl || process.env.AI_URL || 'http://text-corrector:8080';
  const MODEL = model || process.env.AI_MODEL || 'qwen2.5-1.5b-instruct-q4_k_m.gguf';
  const DEFAULT_PROMPT = defaultPrompt || '';
  const TIMEOUT_MS = Math.max(5000, parseInt(process.env.LESSON_AI_TIMEOUT_MS || '120000', 10) || 120000);
  const MIN_CHARS = 20;
  const MAX_INPUT_CHARS = 4000;
  const TEXT_MAX = 5000;
  const MAX_ATTEMPTS = 3;

  let started = false;
  let stopped = false;
  let idleMs = IDLE_MIN_MS;
  let wake = null;
  let processing = false;
  let currentId = null;
  let startedAt = null;
  const stats = { checks: 0, formatted: 0, unchanged: 0, errors: 0, last_at: null, last_error: null };
  const attempts = new Map();

  function sleep(ms) {
    return new Promise((resolve) => {
      const t = setTimeout(() => { wake = null; resolve(); }, ms);
      wake = () => { clearTimeout(t); wake = null; resolve(); };
    });
  }

  function notify() {
    if (wake) wake();
    if (bus) bus.publish();
  }

  if (bus) bus.subscribe(() => notify());

  async function isEnabled() {
    return String(await getSetting('lesson_ai_enabled', 'true')) !== 'false';
  }

  async function claimNext() {
    const client = await pool.connect();
    try {
      await client.query('BEGIN');
      const { rows } = await client.query(
        `SELECT lr.id, lr.text, lr.text_original, lr.lesson_date, lr.lesson_time, lr.author_id,
                g.name AS group_name, g.branch_id
         FROM lesson_reports lr
         JOIN groups g ON g.id = lr.group_id
         WHERE lr.ai_status = 'pending'
         ORDER BY lr.id ASC LIMIT 1 FOR UPDATE OF lr SKIP LOCKED`
      );
      if (!rows.length) {
        await client.query('COMMIT');
        return null;
      }
      await client.query(`UPDATE lesson_reports SET ai_status = 'processing' WHERE id = $1`, [rows[0].id]);
      await client.query('COMMIT');
      return rows[0];
    } catch (e) {
      await client.query('ROLLBACK').catch(() => {});
      throw e;
    } finally {
      client.release();
    }
  }
async function resolveActiveProfile() {
    try {
      const active = await getSetting('ai_active_profile', 'native');
      if (active && active !== 'native') {
        const raw = await getSetting('ai_profiles', '[]');
        const list = JSON.parse(raw || '[]');
        if (Array.isArray(list)) {
          return list.find(p => p && p.id === active && p.base_url && p.model) || null;
        }
      }
    } catch (e) {}
    return null;
  }

  function normalizeOpenAiBase(base) {
    const b = String(base || '').trim().replace(/\/+$/, '');
    if (!/^https?:\/\//i.test(b)) return null;
    if (!/\/v1$/i.test(b)) return b + '/v1';
    return b;
  }

  async function callModel(userText, systemPrompt) {
    const profile = await resolveActiveProfile();
    const headers = { 'Content-Type': 'application/json' };
    let url;
    let model;
    let maxTokens;
    if (profile) {
      const base = normalizeOpenAiBase(profile.base_url);
      if (!base) throw new Error('Некорректный base_url профиля ИИ');
      url = `${base}/chat/completions`;
      model = profile.model;
      if (profile.api_key) headers.Authorization = `Bearer ${profile.api_key}`;
      maxTokens = parseInt(profile.max_tokens, 10) || Math.min(4096, Math.max(1024, userText.length * 2 + 512));
    } else {
      url = `${AI_URL.replace(/\/+$/, '')}/v1/chat/completions`;
      model = MODEL;
      maxTokens = Math.min(1536, Math.max(512, userText.length + 512));
    }
    const controller = new AbortController();
    const timer = setTimeout(() => controller.abort(), TIMEOUT_MS);
    try {
      const res = await fetch(url, {
        method: 'POST',
        headers,
        signal: controller.signal,
        body: JSON.stringify({
          model,
          messages: [
            { role: 'system', content: systemPrompt },
            { role: 'user', content: userText },
          ],
          temperature: 0.1,
          max_tokens: maxTokens,
        }),
      });
      if (!res.ok) throw new Error(`AI service error: ${res.status}`);
      const data = await res.json();
      const choice = data.choices && data.choices[0];
      return (choice && choice.message && choice.message.content || '').trim();
    } finally {
      clearTimeout(timer);
    }
  }

  function normalizeOutput(out) {
    let s = String(out || '').trim();
    if (!s) return '';
    s = s.replace(/^```[a-zA-Z]*\s*/, '').replace(/```$/, '').trim();
    s = s.replace(/^(?:итоговый|результативный|готовый|итог)\s*текст\s*(?:отчёта|отчета|report)?\s*[:—-]\s*/i, '').trim();
    s = s.replace(/^["'«”]+/, '').replace(/["'«»"]+$/, '').trim();
    s = s.replace(/\r\n/g, '\n').replace(/\n{3,}/g, '\n\n');
    return s;
  }
async function finish(row, status, text, error, aiText) {
    await pool.query(
      `UPDATE lesson_reports SET
         text = $1, text_ai = $2, ai_status = $3, ai_error = $4, ai_checked_at = now(), updated_at = now()
       WHERE id = $5`,
      [text, aiText, status, error || null, row.id]
    );
    attempts.delete(row.id);
    stats.last_at = new Date().toISOString();
    stats.last_error = error || null;
    if (onDone) await onDone({ row, status, text, aiText, error: error || null });
  }

  async function processOne(row) {
    const original = String(row.text_original || row.text || '').trim();
    if (original.length < MIN_CHARS) {
      await finish(row, 'skipped', original, null, null);
      stats.unchanged++;
      return true;
    }
    const prompt = (await getSetting('lesson_ai_prompt', DEFAULT_PROMPT)) || DEFAULT_PROMPT;
    const date = String(row.lesson_date).slice(0, 10);
    const time = row.lesson_time ? String(row.lesson_time).slice(0, 5) : '';
    const input = original.length > MAX_INPUT_CHARS ? original.slice(0, MAX_INPUT_CHARS) : original;
    const context = [
      `Группа: ${row.group_name || '—'}`,
      `Дата занятия: ${date}`,
      time ? `Время занятия: ${time}` : '',
      '',
      'Текст отчёта:',
      input,
    ].filter(l => l !== '').join('\n');
    try {
      const out = normalizeOutput(await callModel(context, prompt));
      if (!out || out.length > TEXT_MAX) {
        const reason = out ? 'Модель вернула слишком длинный текст' : 'Модель вернула пустой ответ';
        await finish(row, 'error', original, reason, null);
        stats.errors++;
        return true;
      }
      const changed = out !== original;
      await finish(row, changed ? 'done' : 'skipped', changed ? out : original, null, changed ? out : null);
      stats.checks++;
      if (changed) stats.formatted++; else stats.unchanged++;
      return true;
    } catch (e) {
      const message = (e && e.message ? e.message : 'error').slice(0, 500);
      const tries = (attempts.get(row.id) || 0) + 1;
      if (tries < MAX_ATTEMPTS) {
        attempts.set(row.id, tries);
        await pool.query(`UPDATE lesson_reports SET ai_status = 'pending', ai_error = $1 WHERE id = $2`, [message, row.id]);
        if (logAudit) await logAudit(null, 'lesson_report.ai.retry', { id: row.id, attempt: tries, error: message });
        return false;
      }
      await finish(row, 'error', original, message, null);
      stats.errors++;
      if (logAudit) await logAudit(null, 'lesson_report.ai.error', { id: row.id, error: message });
      return true;
    }
  }
async function loop() {
    while (!stopped) {
      let row = null;
      try {
        if (!(await isEnabled())) {
          await sleep(IDLE_MAX_MS);
          continue;
        }
        row = await claimNext();
      } catch (e) {
        console.error('Lesson AI claim error:', e.message);
        await sleep(IDLE_MAX_MS);
        continue;
      }
      if (!row) {
        await sleep(idleMs);
        idleMs = Math.min(idleMs * 2, IDLE_MAX_MS);
        continue;
      }
      idleMs = IDLE_MIN_MS;
      processing = true;
      currentId = row.id;
      let ok = true;
      try {
        ok = await processOne(row);
      } catch (e) {
        console.error('Lesson AI process error:', e.message);
      } finally {
        processing = false;
        currentId = null;
      }
      if (!ok) await sleep(IDLE_MAX_MS);
    }
  }

  function resetStale() {
    return pool.query(`UPDATE lesson_reports SET ai_status = 'pending' WHERE ai_status = 'processing'`);
  }

  function start() {
    if (started) return;
    started = true;
    startedAt = Date.now();
    resetStale()
      .catch((e) => console.error('Lesson AI reset error:', e.message))
      .finally(() => { loop().catch((e) => console.error('Lesson AI loop error:', e.message)); });
  }

  function stop() {
    stopped = true;
    notify();
  }

  function getInfo() {
    return {
      started_at: startedAt ? new Date(startedAt).toISOString() : null,
      uptime_ms: startedAt ? Date.now() - startedAt : 0,
      processing,
      current_id: currentId,
      config: { idle_min_ms: IDLE_MIN_MS, idle_max_ms: IDLE_MAX_MS, timeout_ms: TIMEOUT_MS, model: MODEL, ai_url: AI_URL },
      ...stats,
    };
  }

  return { start, stop, notify, getInfo };
}

module.exports = { createEntryAutoChecker, createPhotoEnhanceWorker, createLessonReportChecker };