import http from 'http';
import https from 'https';
import { URL } from 'url';
import crypto from 'crypto';
import fs from 'fs';
import path from 'path';
import { fileURLToPath } from 'url';
import log from '../src/utils/logger.js';

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);
const ACCOUNTS_FILE = path.join(__dirname, '..', 'data', 'accounts.json');

const CLIENT_ID = '1071006060591-tmhssin2h21lcre235vtolojh4g403ep.apps.googleusercontent.com';
const CLIENT_SECRET = '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';
const STATE = crypto.randomUUID();

const SCOPES = [
  'https://www.googleapis.com/auth/cloud-platform',
  'https://www.googleapis.com/auth/userinfo.email',
  'https://www.googleapis.com/auth/userinfo.profile',
  'https://www.googleapis.com/auth/cclog',
  'https://www.googleapis.com/auth/experimentsandconfigs'
];

function generateAuthUrl(port) {
  const params = new URLSearchParams({
    access_type: 'offline',
    client_id: CLIENT_ID,
    prompt: 'consent',
    redirect_uri: `http://localhost:${port}/oauth-callback`,
    response_type: 'code',
    scope: SCOPES.join(' '),
    state: STATE
  });
  return `https://accounts.google.com/o/oauth2/v2/auth?${params.toString()}`;
}

function exchangeCodeForToken(code, port) {
  return new Promise((resolve, reject) => {
    const postData = new URLSearchParams({
      code: code,
      client_id: CLIENT_ID,
      redirect_uri: `http://localhost:${port}/oauth-callback`,
      grant_type: 'authorization_code'
    });
    
    if (CLIENT_SECRET) {
      postData.append('client_secret', CLIENT_SECRET);
    }
    
    const data = postData.toString();
    
    const options = {
      hostname: 'oauth2.googleapis.com',
      path: '/token',
      method: 'POST',
      headers: {
        'Content-Type': 'application/x-www-form-urlencoded',
        'Content-Length': Buffer.byteLength(data)
      }
    };
    
    const req = https.request(options, (res) => {
      let body = '';
      res.on('data', chunk => body += chunk);
      res.on('end', () => {
        if (res.statusCode === 200) {
          resolve(JSON.parse(body));
        } else {
          reject(new Error(`HTTP ${res.statusCode}: ${body}`));
        }
      });
    });
    
    req.on('error', reject);
    req.write(data);
    req.end();
  });
}

const server = http.createServer((req, res) => {
  const port = server.address().port;
  const url = new URL(req.url, `http://localhost:${port}`);
  
  if (url.pathname === '/oauth-callback') {
    const code = url.searchParams.get('code');
    const error = url.searchParams.get('error');
    
    if (code) {
      log.info('收到授权码，正在交换 Token...');
      exchangeCodeForToken(code, port).then(tokenData => {
        const account = {
          access_token: tokenData.access_token,
          refresh_token: tokenData.refresh_token,
          expires_in: tokenData.expires_in,
          timestamp: Date.now()
        };
        
        let accounts = [];
        try {
          if (fs.existsSync(ACCOUNTS_FILE)) {
            accounts = JSON.parse(fs.readFileSync(ACCOUNTS_FILE, 'utf-8'));
          }
        } catch (err) {
          log.warn('读取 accounts.json 失败，将创建新文件');
        }
        
        accounts.push(account);
        
        const dir = path.dirname(ACCOUNTS_FILE);
        if (!fs.existsSync(dir)) {
          fs.mkdirSync(dir, { recursive: true });
        }
        
        fs.writeFileSync(ACCOUNTS_FILE, JSON.stringify(accounts, null, 2));
        
        log.info(`Token 已保存到 ${ACCOUNTS_FILE}`);
        //log.info(`过期时间: ${account.expires_in}秒`);
        
        res.writeHead(200, { 'Content-Type': 'text/html; charset=utf-8' });
        res.end('<h1>授权成功！</h1><p>Token 已保存，可以关闭此页面。</p>');
        
        setTimeout(() => server.close(), 1000);
      }).catch(err => {
        log.error('Token 交换失败:', err.message);
        
        res.writeHead(200, { 'Content-Type': 'text/html; charset=utf-8' });
        res.end('<h1>Token 获取失败</h1><p>查看控制台错误信息</p>');
        
        setTimeout(() => server.close(), 1000);
      });
    } else {
      log.error('授权失败:', error || '未收到授权码');
      res.writeHead(200, { 'Content-Type': 'text/html; charset=utf-8' });
      res.end('<h1>授权失败</h1>');
      setTimeout(() => server.close(), 1000);
    }
  } else {
    res.writeHead(404);
    res.end('Not Found');
  }
});

server.listen(0, () => {
  const port = server.address().port;
  const authUrl = generateAuthUrl(port);
  log.info(`服务器运行在 http://localhost:${port}`);
  log.info('请在浏览器中打开以下链接进行登录：');
  console.log(`\n${authUrl}\n`);
  log.info('等待授权回调...');
});