/**
 * 云函数：douyinManager
 * 代理抖音/TikHub 相关接口，避免前端暴露 TikHub 地址和 token。
 *
 * 部署后把函数 objectId 填入 src/app/services/cloud-functions.ts 的 douyin。
 */
const DOUYIN_API_BASE_URL = (readEnv('DOUYIN_API_BASE_URL') || readEnv('VOC_SOCIAL_BASE_URL') || 'https://server.fmode.cn/api/voc-social').replace(/\/+$/, '');
const IS_TIKHUB_DIRECT = /api\.tikhub\.io/i.test(DOUYIN_API_BASE_URL);
const LOCAL_VOC_TOKEN_FALLBACK = 'r:33c57d404c8fffc9b19199a4da0bb663';
const VOC_SOCIAL_TOKEN = readEnv('DOUYIN_API_TOKEN') || readEnv('VOC_TOKEN') || readEnv('TRANSCRIPTION_VOC_TOKEN') || readEnv('VOICE_TOKEN') || readEnv('OPENCLAW_VOC_TOKEN') || readEnv('VOC_SOCIAL_TOKEN') || LOCAL_VOC_TOKEN_FALLBACK;
const TIKHUB_TOKEN = readEnv('TIKHUB_TOKEN') || 'gqsZHfMWgAiMwV+ITbmZy0qALADWBZVS7QnV7kKJe9CwzgWgJG+7bwK+GQ==';
const DOUYIN_API_TOKEN = IS_TIKHUB_DIRECT ? (readEnv('DOUYIN_API_TOKEN') || TIKHUB_TOKEN) : VOC_SOCIAL_TOKEN;

const ROUTES = {
  searchVideos: { method: 'POST', path: '/douyin/search/fetch_general_search_v2' },
  challengeSearch: { method: 'POST', path: '/douyin/search/fetch_challenge_search_v2' },
  videoDetail: { method: 'GET', path: '/douyin/app/v3/fetch_one_video_v3' },
  userProfileWeb: { method: 'GET', path: '/douyin/web/handler_user_profile_v2' },
  userProfileApp: { method: 'GET', path: '/douyin/app/v3/handler_user_profile' },
  userPosts: { method: 'GET', path: '/douyin/app/v3/fetch_user_post_videos' },
  comments: { method: 'GET', path: '/douyin/app/v3/fetch_video_comments' },
  replies: { method: 'GET', path: '/douyin/app/v3/fetch_video_comment_replies' },
};

async function handler(request, response) {
  try {
    const action = pickParam(request, 'action') || 'call';
    if (action === 'diagnose') {
      return diagnose(request, response);
    }

    if (action !== 'call') {
      return response.json({ code: 400, success: false, error: `未知 action: ${action}` });
    }

    const routeName = String(pickParam(request, 'route') || '').trim();
    const route = ROUTES[routeName];
    if (!route) {
      return response.json({ code: 400, success: false, error: '不支持的抖音接口' });
    }

    const params = pickParam(request, 'params') || {};
    const body = pickParam(request, 'payload', 'data') || {};
    const data = route.method === 'GET'
      ? await requestJson('GET', route.path, { ...body, ...params })
      : await requestJson('POST', route.path, body);

    response.json(data);
  } catch (error) {
    console.error('douyinManager failed:', error && error.message ? error.message : error);
    response.json({ code: 500, success: false, error: error && error.message ? error.message : '抖音服务调用失败' });
  }
}

async function requestJson(method, path, payload) {
  if (!DOUYIN_API_TOKEN) {
    return {
      code: 400,
      success: false,
      error: '抖音数据网关未配置有效 token：FMode voc-social 请配置 DOUYIN_API_TOKEN、VOC_TOKEN 或 VOC_SOCIAL_TOKEN；TikHub 直连才使用 TIKHUB_TOKEN。'
    };
  }

  const url = new URL(`${DOUYIN_API_BASE_URL}${normalizeDouyinPath(path)}`);
  const init = {
    method,
    headers: {
      'Content-Type': 'application/json',
      'Accept': 'application/json',
      'Authorization': bearerAuth(DOUYIN_API_TOKEN),
    },
  };

  if (method === 'GET') {
    for (const [key, value] of Object.entries(payload || {})) {
      if (value !== undefined && value !== null && value !== '') {
        url.searchParams.set(key, String(value));
      }
    }
  } else {
    init.body = JSON.stringify(stripEmpty(payload || {}));
  }

  let r;
  try {
    r = await fetch(url.toString(), init);
  } catch (error) {
    return {
      code: 502,
      success: false,
      error: `抖音数据网关网络请求失败：${formatFetchError(error)}。base=${maskBaseUrl(DOUYIN_API_BASE_URL)} route=${path}`
    };
  }
  const text = await r.text();
  let data = null;
  try { data = text ? JSON.parse(text) : null; } catch {}
  if (!r.ok) {
    return { code: r.status, success: false, error: readError(data, text) || `抖音数据接口请求失败 HTTP ${r.status}` };
  }
  return data || { code: 500, success: false, error: '服务返回异常' };
}

async function diagnose(request, response) {
  const routeName = String(pickParam(request, 'route') || 'videoDetail').trim();
  const route = ROUTES[routeName] || ROUTES.videoDetail;
  const awemeId = String(pickParam(request, 'awemeId') || '7592116912205630761').trim();
  const payload = routeName === 'videoDetail' ? { aweme_id: awemeId } : {};
  const result = {
    code: 200,
    success: true,
    data: {
      baseUrl: maskBaseUrl(DOUYIN_API_BASE_URL),
      isTikhubDirect: IS_TIKHUB_DIRECT,
      tokenConfigured: !!DOUYIN_API_TOKEN,
      tokenSource: tokenSource(),
      routeName,
      routePath: route.path,
      normalizedPath: normalizeDouyinPath(route.path),
      probe: null,
    }
  };

  if (String(pickParam(request, 'probe') || '') === '1') {
    result.data.probe = await requestJson(route.method, route.path, payload);
  }

  return response.json(result);
}

function normalizeDouyinPath(path) {
  if (IS_TIKHUB_DIRECT && !path.startsWith('/api/v1/')) {
    return `/api/v1${path}`;
  }
  return path;
}

function pickParam(request, ...names) {
  const sources = [request.params, request.body, request];
  for (const src of sources) {
    if (!src || typeof src !== 'object') continue;
    for (const n of names) {
      const v = src[n];
      if (v !== undefined && v !== null && v !== '') return v;
    }
  }
  return null;
}

function stripEmpty(value) {
  if (!value || typeof value !== 'object') return value;
  const out = Array.isArray(value) ? [] : {};
  for (const [key, val] of Object.entries(value)) {
    if (val === undefined || val === null || val === '') continue;
    if (val && typeof val === 'object' && !Array.isArray(val)) {
      const nested = stripEmpty(val);
      if (Object.keys(nested).length) out[key] = nested;
    } else {
      out[key] = val;
    }
  }
  return out;
}

function readError(data, fallback) {
  const detail = data?.detail;
  if (detail === 'Not Found') return '抖音数据接口地址未找到，请检查 DOUYIN_API_BASE_URL 是否配置为 https://server.fmode.cn/api/voc-social';
  const message = data?.mess || data?.message || data?.msg || data?.error?.message || data?.error || detail || fallback || '';
  if (/company或用户信息不存在/.test(String(message))) {
    return '当前抖音数据网关 token 未绑定有效用户或公司，请在云函数配置 DOUYIN_API_TOKEN/VOC_TOKEN/VOC_SOCIAL_TOKEN，不能使用 TikHub token。';
  }
  return message;
}

function bearerAuth(token) {
  const value = String(token || '').trim();
  return /^Bearer\s+/i.test(value) ? value : `Bearer ${value}`;
}

function tokenSource() {
  if (readEnv('DOUYIN_API_TOKEN')) return 'DOUYIN_API_TOKEN';
  if (readEnv('VOC_TOKEN')) return 'VOC_TOKEN';
  if (readEnv('TRANSCRIPTION_VOC_TOKEN')) return 'TRANSCRIPTION_VOC_TOKEN';
  if (readEnv('VOICE_TOKEN')) return 'VOICE_TOKEN';
  if (readEnv('OPENCLAW_VOC_TOKEN')) return 'OPENCLAW_VOC_TOKEN';
  if (readEnv('VOC_SOCIAL_TOKEN')) return 'VOC_SOCIAL_TOKEN';
  if (IS_TIKHUB_DIRECT && readEnv('TIKHUB_TOKEN')) return 'TIKHUB_TOKEN';
  if (!IS_TIKHUB_DIRECT && LOCAL_VOC_TOKEN_FALLBACK) return 'LOCAL_VOC_TOKEN_FALLBACK';
  return IS_TIKHUB_DIRECT ? 'TIKHUB_TOKEN_FALLBACK' : '';
}

function formatFetchError(error) {
  const message = error && error.message ? error.message : String(error || 'fetch failed');
  const cause = error && error.cause ? `；cause=${error.cause.code || error.cause.message || error.cause}` : '';
  return `${message}${cause}`;
}

function maskBaseUrl(value) {
  return String(value || '').replace(/(token=)[^&]+/ig, '$1***');
}

function readEnv(name) {
  if (typeof process !== 'undefined' && process.env && process.env[name]) {
    return process.env[name];
  }
  return '';
}