const fs = require('fs');
const path = require('path');

/**
 * SQL 语法修复脚本：修复自动替换产生的 SQL 语法错误
 */

class SQLSyntaxFixer {
  constructor() {
    this.filesToFix = [
      'services/matchingService.js',
      'routes/matchingAdmin.js', 
      'routes/transfers.js',
      'routes/matching.js'
    ];
  }
  
  /**
   * 修复单个文件中的 SQL 语法错误
   * @param {string} filePath - 文件路径
   */
  async fixFile(filePath) {
    const fullPath = path.join(process.cwd(), filePath);
    
    if (!fs.existsSync(fullPath)) {
      console.log(`文件不存在: ${filePath}`);
      return;
    }
    
    console.log(`正在修复文件: ${filePath}`);
    
    let content = fs.readFileSync(fullPath, 'utf8');
    let originalContent = content;
    
    // 1. 修复 WHERE source_type = 'allocation' FROM transfers 的错误顺序
    content = content.replace(
      /WHERE source_type = 'allocation' FROM transfers/g,
      "FROM transfers WHERE source_type = 'allocation'"
    );
    
    // 2. 修复多个 WHERE 子句的问题
    content = content.replace(
      /FROM transfers WHERE source_type = 'allocation'([\s\S]*?)WHERE/g,
      "FROM transfers WHERE source_type = 'allocation'$1AND"
    );
    
    // 3. 修复 INSERT 语句中的引号问题
    content = content.replace(
      /'allocation'/g,
      "'allocation'"
    );
    
    // 4. 修复 JOIN 语句中的表别名问题
    content = content.replace(
      /FROM transfers oa WHERE oa\.source_type = 'allocation'/g,
      "FROM transfers oa WHERE oa.source_type = 'allocation'"
    );
    
    // 5. 修复复杂查询中的语法问题
    content = this.fixComplexQueries(content, filePath);
    
    if (content !== originalContent) {
      fs.writeFileSync(fullPath, content);
      console.log(`✓ 已修复: ${filePath}`);
    } else {
      console.log(`- 无需修复: ${filePath}`);
    }
  }
  
  /**
   * 修复复杂查询
   * @param {string} content - 文件内容
   * @param {string} filePath - 文件路径
   * @returns {string} 修复后的内容
   */
  fixComplexQueries(content, filePath) {
    if (filePath.includes('matchingService.js')) {
      // 修复 matchingService.js 中的特定查询
      
      // 修复获取匹配目标的查询
      content = content.replace(
        /FROM transfers oa\s+WHERE oa\.source_type = 'allocation'\s+JOIN users u ON oa\.from_user_id = u\.id/g,
        "FROM transfers oa JOIN users u ON oa.from_user_id = u.id WHERE oa.source_type = 'allocation'"
      );
      
      // 修复获取用户待处理分配的查询
      content = content.replace(
        /SELECT \* FROM transfers WHERE source_type = 'allocation' WHERE matching_order_id = \? ORDER BY cycle_number, created_at/g,
        "SELECT * FROM transfers WHERE source_type = 'allocation' AND matching_order_id = ? ORDER BY cycle_number, created_at"
      );
      
      // 修复检查周期完成的查询
      content = content.replace(
        /SELECT COUNT\(\*\) as count FROM transfers WHERE source_type = 'allocation' WHERE matching_order_id = \? AND cycle_number = \? AND status = "pending"/g,
        "SELECT COUNT(*) as count FROM transfers WHERE source_type = 'allocation' AND matching_order_id = ? AND cycle_number = ? AND status = 'pending'"
      );
    }
    
    if (filePath.includes('matchingAdmin.js')) {
      // 修复 matchingAdmin.js 中的查询
      content = content.replace(
        /FROM transfers oa WHERE oa\.source_type = 'allocation'\s+JOIN/g,
        "FROM transfers oa JOIN"
      );
      
      // 在 JOIN 后添加 WHERE 条件
      content = content.replace(
        /(FROM transfers oa JOIN[\s\S]*?)WHERE(?!.*source_type)/g,
        "$1WHERE oa.source_type = 'allocation' AND"
      );
    }
    
    if (filePath.includes('matching.js')) {
      // 修复 matching.js 中的查询
      content = content.replace(
        /LEFT JOIN transfers oa ON mo\.id = oa\.matching_order_id WHERE oa\.source_type = 'allocation'/g,
        "LEFT JOIN transfers oa ON mo.id = oa.matching_order_id AND oa.source_type = 'allocation'"
      );
    }
    
    return content;
  }
  
  /**
   * 执行所有文件的修复
   */
  async fixAllFiles() {
    console.log('开始修复 SQL 语法错误...');
    console.log('=' .repeat(60));
    
    for (const filePath of this.filesToFix) {
      try {
        await this.fixFile(filePath);
      } catch (error) {
        console.error(`修复文件 ${filePath} 失败:`, error.message);
      }
    }
    
    console.log('\n' + '=' .repeat(60));
    console.log('✓ SQL 语法修复完成！');
  }
}

async function main() {
  const fixer = new SQLSyntaxFixer();
  await fixer.fixAllFiles();
}

// 如果直接运行此脚本
if (require.main === module) {
  main().catch(console.error);
}

module.exports = SQLSyntaxFixer;