/**
 * 修复锁定的事务
 * 强制终止等待提交的进程
 */

require('dotenv').config();
const mysql = require('mysql2/promise');

async function fixLockedTransaction() {
    let connection;

    try {
        connection = await mysql.createConnection({
            host: process.env.DB_HOST,
            port: process.env.DB_PORT || 3306,
            user: process.env.DB_USER,
            password: process.env.DB_PASSWORD,
            database: process.env.DB_DATABASE
        });

        console.log('✅ 已连接到数据库');

        // 1. 查找所有waiting for handler commit的进程
        console.log('\n📋 查找锁定的进程...');
        const [processes] = await connection.query(
            "SELECT Id, State, Info FROM INFORMATION_SCHEMA.PROCESSLIST WHERE State LIKE '%waiting for handler commit%'"
        );

        console.log(`找到 ${processes.length} 个锁定的进程`);

        // 2. 终止所有锁定的进程
        let killedCount = 0;
        for (const p of processes) {
            try {
                console.log(`  正在终止进程 ${p.Id}: ${p.Info?.substring(0, 100)}...`);
                await connection.query(`KILL ${p.Id}`);
                console.log(`  ✅ 已终止进程 ${p.Id}`);
                killedCount++;
            } catch (err) {
                console.log(`  ⚠️ 无法终止进程 ${p.Id}:`, err.message);
            }
        }

        console.log(`\n✅ 成功终止 ${killedCount} 个锁定的进程`);

        // 3. 清理可能重复的确认记录
        console.log('\n🧹 清理可能的重复记录...');
        const [duplicates] = await connection.query(`
            SELECT user_id, training_unit_id, COUNT(*) as count
            FROM training_confirmations
            GROUP BY user_id, training_unit_id
            HAVING count > 1
        `);

        if (duplicates.length > 0) {
            console.log(`发现 ${duplicates.length} 组重复记录，正在清理...`);
            for (const dup of duplicates) {
                // 保留最早的记录，删除其他
                await connection.query(`
                    DELETE FROM training_confirmations
                    WHERE user_id = ? AND training_unit_id = ?
                    AND id NOT IN (
                        SELECT id FROM (
                            SELECT MIN(id) as id FROM training_confirmations
                            WHERE user_id = ? AND training_unit_id = ?
                        ) as temp
                    )
                `, [dup.user_id, dup.training_unit_id, dup.user_id, dup.training_unit_id]);
                console.log(`  ✅ 清理了 user_id=${dup.user_id}, training_unit_id=${dup.training_unit_id} 的重复记录`);
            }
        } else {
            console.log('没有发现重复记录');
        }

        console.log('\n✅ 所有操作完成！');
        console.log('\n💡 现在可以重新测试预招录确认功能了');

    } catch (error) {
        console.error('❌ 操作失败:', error.message);
        process.exit(1);
    } finally {
        if (connection) {
            await connection.end();
        }
    }
}

fixLockedTransaction();