import fs from 'node:fs';
import path from 'node:path';
import kafka from 'kafka-node';
import { fileURLToPath } from 'node:url';

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

console.log('--- 环境检查脚本开始 ---');
console.log('当前时间:', new Date().toISOString());
console.log('当前目录 (cwd):', process.cwd());
console.log('脚本目录:', __dirname);

// 1. 检查 .env 文件
const pathsToCheck = [
  path.resolve(process.cwd(), '.env'),
  path.resolve(__dirname, '../.env'),
  path.resolve(__dirname, '../../.env')
];
let envPath = null;
for (const p of pathsToCheck) {
  if (fs.existsSync(p)) {
    envPath = p;
    break;
  }
}

let envConfig = {};

if (envPath) {
  console.log('✅ 找到 .env 文件:', envPath);
  try {
    const content = fs.readFileSync(envPath, 'utf8');
    const lines = content.split(/\r?\n/);
    lines.forEach(line => {
      const trimmed = line.trim();
      if (!trimmed || trimmed.startsWith('#')) return;
      const idx = trimmed.indexOf('=');
      if (idx <= 0) return;
      const key = trimmed.slice(0, idx).trim();
      let val = trimmed.slice(idx + 1).trim();
      if ((val.startsWith('"') && val.endsWith('"')) || (val.startsWith("'") && val.endsWith("'"))) {
        val = val.slice(1, -1);
      }
      envConfig[key] = val;
    });
    console.log('已加载环境变量:', Object.keys(envConfig).filter(k => k.startsWith('KAFKA') || k.startsWith('PG') || k.startsWith('REDIS')));
  } catch (e) {
    console.error('❌ 读取 .env 失败:', e.message);
  }
} else {
  console.warn('⚠️ .env 文件不存在! 将使用系统环境变量或默认值');
}

// 2. 确定 Kafka 配置
const brokers = envConfig.KAFKA_BROKERS || process.env.KAFKA_BROKERS || 'localhost:9092';
const topic = envConfig.KAFKA_TOPIC || process.env.KAFKA_TOPIC || 'blwlog4Nodejs-rcu-heartbeat-topic';

console.log('\n--- Kafka 连接配置 ---');
console.log('Brokers:', brokers);
console.log('Topic:', topic);

// 3. 测试连接
console.log('\n--- 开始连接测试 ---');
try {
  const client = new kafka.KafkaClient({ 
    kafkaHost: brokers, 
    connectTimeout: 5000,
    requestTimeout: 5000 
  });

  client.on('ready', () => {
    console.log('✅ Kafka Client 连接成功 (Ready)');
    
    console.log('正在加载 Topic Metadata...');
    client.loadMetadataForTopics([topic], (err, results) => {
      if (err) {
        console.error('❌ 获取 Metadata 失败:', err);
        client.close();
        process.exit(1);
      }
      
      console.log('✅ Metadata 获取成功');
      // console.log(JSON.stringify(results, null, 2));
      
      const metadata = results[1].metadata;
      if (metadata[topic]) {
        console.log(`✅ Topic [${topic}] 存在，分区信息:`);
        const partitions = metadata[topic];
        Object.keys(partitions).forEach(p => {
            console.log(`   - Partition ${p}: Leader ${partitions[p].leader}, Replicas ${partitions[p].replicas}`);
        });
      } else {
        console.warn(`⚠️ Topic [${topic}] 在 Metadata 中未找到 (可能自动创建中)`);
      }
      
      client.close(() => {
          console.log('\n测试完成: 网络连接正常');
          process.exit(0);
      });
    });
  });

  client.on('error', (err) => {
    console.error('❌ Kafka 连接错误:', err);
    // 不立即退出，等待超时或其他错误
  });

  // 10秒超时兜底
  setTimeout(() => {
    console.error('❌ 测试超时 (10秒) - 可能是防火墙或网络不通');
    process.exit(1);
  }, 10000);

} catch (e) {
  console.error('❌ 初始化 Kafka Client 异常:', e);
}