/**
 * Engine client — единая точка вызовов к zeropost-engine
 */
const ENGINE_URL = process.env.ENGINE_URL || 'http://127.0.0.1:3040';
const ENGINE_SECRET = process.env.ENGINE_SECRET || 'zeropost_internal_2026';

async function call(path, options = {}) {
  const { userId, body, method = 'GET' } = options;
  const headers = {
    'Content-Type': 'application/json',
    'x-internal-secret': ENGINE_SECRET,
  };
  if (userId) headers['x-user-id'] = String(userId);

  const url = `${ENGINE_URL}${path}`;
  const res = await fetch(url, {
    method,
    headers,
    body: body ? JSON.stringify(body) : undefined,
    cache: 'no-store',
  });
  if (!res.ok) {
    const err = await res.json().catch(() => ({ error: res.statusText }));
    const e = new Error(err.error || `Engine ${res.status}`);
    e.status = res.status;
    e.code = err.code;
    throw e;
  }
  return res.json();
}

export const engine = {
  // Channels
  listChannels: (userId) => call('/api/channels/', { userId }),
  getChannel: (userId, id) => call(`/api/channels/${id}`, { userId }),
  createChannel: (userId, data) => call('/api/channels/', { userId, method: 'POST', body: data }),
  updateChannel: (userId, id, data) => call(`/api/channels/${id}`, { userId, method: 'PATCH', body: data }),
  deleteChannel: (userId, id) => call(`/api/channels/${id}`, { userId, method: 'DELETE' }),

  // Generation
  generate: (userId, data) => call('/api/generate/', { userId, method: 'POST', body: data }),
  getJob: (userId, id) => call(`/api/generate/${id}`, { userId }),
  transformPost: (userId, data) => call('/api/generate/transform', { userId, method: 'POST', body: data }),
  generatePostImage: (userId, data) => call('/api/generate/post-image', { userId, method: 'POST', body: data }),
  topicsIdeas: (userId, data) => call('/api/generate/topics-ideas', { userId, method: 'POST', body: data }),
  getImageStyles: () => call('/api/generate/image-styles'),

  // User posts (черновики / запланированные / опубликованные)
  listUserPosts: (userId, params = {}) => {
    const qs = new URLSearchParams(params).toString();
    return call(`/api/user-posts${qs ? '?' + qs : ''}`, { userId });
  },
  savePost: (userId, data) => call('/api/user-posts', { userId, method: 'POST', body: data }),
  getPost: (userId, id) => call(`/api/user-posts/${id}`, { userId }),
  updatePost: (userId, id, data) => call(`/api/user-posts/${id}`, { userId, method: 'PATCH', body: data }),
  deletePost: (userId, id) => call(`/api/user-posts/${id}`, { userId, method: 'DELETE' }),
  publishPost: (userId, id) => call(`/api/user-posts/${id}/publish`, { userId, method: 'POST' }),

  // Photo search
  photoSearchProfiles: () => call('/api/photo-search/profiles'),
  photoSearchQuota:    () => call('/api/photo-search/quota'),
  photoSearchByQuery:  (data) => call('/api/photo-search/by-query', { method: 'POST', body: data }),

  // Settings (admin)
  listSettings:   (category) => {
    const qs = category ? `?category=${encodeURIComponent(category)}` : '';
    return call(`/api/settings/admin${qs}`);
  },
  updateSetting:  (key, value) => call(`/api/settings/admin/${encodeURIComponent(key)}`, { method: 'PUT', body: { value } }),
  invalidateSettingsCache: () => call('/api/settings/admin/invalidate', { method: 'POST' }),

  // AI usage (admin)
  usageSummary: (params = {}) => {
    const qs = new URLSearchParams(params).toString();
    return call(`/api/usage/summary${qs ? '?' + qs : ''}`);
  },
  usageRecent:  (limit = 20) => call(`/api/usage/recent?limit=${limit}`),

  // Editor notes
  listNotes:    () => call('/api/notes?limit=100'),
  createNote:   (data) => call('/api/notes', { method: 'POST', body: data }),
  updateNote:   (id, data) => call(`/api/notes/${id}`, { method: 'PATCH', body: data }),
  deleteNote:   (id) => call(`/api/notes/${id}`, { method: 'DELETE' }),

  // Calendar
  getCalendar: (userId, params = {}) => {
    const qs = new URLSearchParams(params).toString();
    return call(`/api/calendar${qs ? '?' + qs : ''}`, { userId });
  },
  // Metrics
  getChannelMetrics: (channelId, params = {}) => {
    const qs = new URLSearchParams(params).toString();
    return call(`/api/metrics/channel/${channelId}${qs ? '?' + qs : ''}`);
  },
  getBestTime: (channelId, params = {}) => {
    const qs = new URLSearchParams(params).toString();
    return call(`/api/metrics/best-time/${channelId}${qs ? '?' + qs : ''}`);
  },
  getUserPostMetrics: (userId, channelId, params = {}) => {
    const qs = new URLSearchParams(params).toString();
    return call(`/api/metrics/user-posts/${channelId}${qs ? '?' + qs : ''}`, { userId });
  },
  collectMetrics: () => call('/api/metrics/collect', { method: 'POST' }),
  generateFromUrl: (userId, data) => call('/api/generate/from-url', { userId, method: 'POST', body: data }),

  updateUserPostSchedule: (userId, id, scheduledAt) =>
    call(`/api/user-posts/${id}`, { userId, method: 'PATCH', body: { scheduled_at: scheduledAt } }),
};