// 检查ClickHouse数据库结构的脚本
const { createClient } = require('@clickhouse/client');
const dotenv = require('dotenv');
const path = require('path');
const fs = require('fs');

// 加载环境变量
dotenv.config({ path: path.resolve(__dirname, '../../../.env') });

// 定义输出目录
const DB_REPORTS_DIR = path.resolve(__dirname, '../db-reports');

// 获取ClickHouse配置
const clickhouseHost = process.env.CLICKHOUSE_HOST || 'localhost';
const clickhousePort = process.env.CLICKHOUSE_PORT || '8123';
const clickhouseUser = process.env.CLICKHOUSE_USER || 'default';
const clickhousePassword = process.env.CLICKHOUSE_PASSWORD || '';
const clickhouseDatabase = process.env.CLICKHOUSE_DATABASE || 'default';

console.log('ClickHouse配置:');
console.log(`  - 主机: ${clickhouseHost}`);
console.log(`  - 端口: ${clickhousePort}`);
console.log(`  - 用户: ${clickhouseUser}`);
console.log(`  - 数据库: ${clickhouseDatabase}`);

// 创建ClickHouse客户端 - 使用0.2.10版本的API
const client = createClient({
  url: `http://${clickhouseHost}:${clickhousePort}`,
  username: clickhouseUser,
  password: clickhousePassword,
  database: clickhouseDatabase
});

// 获取所有表
async function getAllTables() {
  console.log('\n获取所有表...');
  
  try {
    const query = `
      SELECT name
      FROM system.tables
      WHERE database = '${clickhouseDatabase}'
    `;
    
    const resultSet = await client.query({
      query,
      format: 'JSONEachRow'
    });
    
    const tables = await resultSet.json();
    
    if (!tables || tables.length === 0) {
      console.log(`数据库 ${clickhouseDatabase} 中没有找到任何表`);
      return null;
    }
    
    console.log(`数据库 ${clickhouseDatabase} 中找到以下表:`);
    tables.forEach(table => {
      console.log(`  - ${table.name}`);
    });
    
    return tables.map(table => table.name);
  } catch (error) {
    console.error('获取所有表时出错:', error);
    return null;
  }
}

// 获取表结构
async function getTableSchema(tableName) {
  console.log(`\n获取表 ${tableName} 的结构...`);
  
  try {
    const query = `
      DESCRIBE TABLE ${clickhouseDatabase}.${tableName}
    `;
    
    const resultSet = await client.query({
      query,
      format: 'JSONEachRow'
    });
    
    const columns = await resultSet.json();
    
    if (!columns || columns.length === 0) {
      console.log(`表 ${tableName} 不存在或没有列`);
      return null;
    }
    
    console.log(`表 ${tableName} 的列:`);
    columns.forEach(column => {
      console.log(`  - ${column.name} (${column.type}, ${column.default_type === '' ? '无默认值' : `默认值: ${column.default_expression}`})`);
    });
    
    return columns;
  } catch (error) {
    console.error(`获取表 ${tableName} 结构时出错:`, error);
    return null;
  }
}

// 获取表数据示例
async function getTableDataSample(tableName, limit = 5) {
  console.log(`\n获取表 ${tableName} 的数据示例 (最多 ${limit} 行)...`);
  
  try {
    const query = `
      SELECT *
      FROM ${clickhouseDatabase}.${tableName}
      LIMIT ${limit}
    `;
    
    const resultSet = await client.query({
      query,
      format: 'JSONEachRow'
    });
    
    const rows = await resultSet.json();
    
    if (!rows || rows.length === 0) {
      console.log(`表 ${tableName} 中没有数据`);
      return null;
    }
    
    console.log(`表 ${tableName} 的数据示例:`);
    rows.forEach((row, index) => {
      console.log(`  行 ${index + 1}:`);
      Object.entries(row).forEach(([key, value]) => {
        console.log(`    ${key}: ${value}`);
      });
    });
    
    return rows;
  } catch (error) {
    console.error(`获取表 ${tableName} 数据示例时出错:`, error);
    return null;
  }
}

// 主函数
async function main() {
  let outputBuffer = '';
  const originalConsoleLog = console.log;
  
  // 重定向console.log到buffer和控制台
  console.log = function() {
    // 调用原始的console.log
    originalConsoleLog.apply(console, arguments);
    
    // 写入到buffer
    outputBuffer += Array.from(arguments).join(' ') + '\n';
  };
  
  try {
    // 获取所有表
    const tables = await getAllTables();
    
    if (!tables) {
      console.error('无法获取表列表');
      process.exit(1);
    }
    
    console.log('\n所有ClickHouse表:');
    console.log(tables.join(', '));
    
    // 获取每个表的结构，但不获取数据示例
    for (const tableName of tables) {
      await getTableSchema(tableName);
      // 移除数据示例检查
      // await getTableDataSample(tableName);
    }
    
    console.log('\nClickHouse数据库结构检查完成');
    
    // 保存输出到指定目录
    const timestamp = new Date().toISOString().replace(/[:.]/g, '-');
    
    // 确保目录存在
    if (!fs.existsSync(DB_REPORTS_DIR)) {
      fs.mkdirSync(DB_REPORTS_DIR, { recursive: true });
    }
    
    const outputPath = path.join(DB_REPORTS_DIR, `clickhouse-schema-${timestamp}.log`);
    fs.writeFileSync(outputPath, outputBuffer);
    originalConsoleLog(`结果已保存到: ${outputPath}`);
    
  } catch (error) {
    console.error('检查ClickHouse数据库结构时出错:', error);
  } finally {
    // 恢复原始的console.log
    console.log = originalConsoleLog;
    
    // 关闭客户端连接
    await client.close();
  }
}

// 导出函数
module.exports = {
  getAllTables,
  getTableSchema,
  getTableDataSample,
  main
}; 

// 如果直接运行此脚本，则执行main函数
if (require.main === module) {
  main().catch(error => {
    console.error('运行脚本时出错:', error);
    process.exit(1);
  });
}