#!/usr/bin/env python3
"""
考培练系统 - 专用数据库回滚工具
针对轻医美连锁业务场景的快速回滚方案

功能：
1. 用户数据回滚
2. 课程数据回滚  
3. 考试数据回滚
4. 岗位数据回滚
5. 基于Binlog的精确回滚

使用方法：
python scripts/kaopeilian_rollback.py --help
"""

import asyncio
import argparse
import json
from datetime import datetime, timedelta
from typing import List, Dict, Optional
import aiomysql
import logging

logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(levelname)s - %(message)s')
logger = logging.getLogger(__name__)

class KaopeilianRollbackTool:
    """考培练系统专用回滚工具"""
    
    def __init__(self):
        self.host = "localhost"
        self.port = 3306
        self.user = "root"
        self.password = "root"
        self.database = "kaopeilian"
        self.connection = None
    
    async def connect(self):
        """连接数据库"""
        try:
            self.connection = await aiomysql.connect(
                host=self.host,
                port=self.port,
                user=self.user,
                password=self.password,
                db=self.database,
                charset='utf8mb4'
            )
            logger.info("✅ 数据库连接成功")
        except Exception as e:
            logger.error(f"❌ 数据库连接失败: {e}")
            raise
    
    async def close(self):
        """关闭连接"""
        if self.connection:
            self.connection.close()
    
    async def get_recent_operations(self, hours: int = 24) -> List[Dict]:
        """获取最近的操作记录"""
        cursor = await self.connection.cursor(aiomysql.DictCursor)
        
        # 查询最近更新的记录
        queries = [
            {
                'table': 'users',
                'sql': f"""
                    SELECT id, username, full_name, updated_at, 'user' as type
                    FROM users 
                    WHERE updated_at >= DATE_SUB(NOW(), INTERVAL {hours} HOUR)
                    ORDER BY updated_at DESC
                """
            },
            {
                'table': 'courses',
                'sql': f"""
                    SELECT id, name, status, updated_at, 'course' as type
                    FROM courses 
                    WHERE updated_at >= DATE_SUB(NOW(), INTERVAL {hours} HOUR)
                    ORDER BY updated_at DESC
                """
            },
            {
                'table': 'exams',
                'sql': f"""
                    SELECT id, user_id, course_id, exam_name, score, updated_at, 'exam' as type
                    FROM exams 
                    WHERE updated_at >= DATE_SUB(NOW(), INTERVAL {hours} HOUR)
                    ORDER BY updated_at DESC
                """
            },
            {
                'table': 'positions',
                'sql': f"""
                    SELECT id, name, code, status, updated_at, 'position' as type
                    FROM positions 
                    WHERE updated_at >= DATE_SUB(NOW(), INTERVAL {hours} HOUR)
                    ORDER BY updated_at DESC
                """
            }
        ]
        
        all_operations = []
        for query in queries:
            try:
                await cursor.execute(query['sql'])
                results = await cursor.fetchall()
                all_operations.extend(results)
            except Exception as e:
                logger.warning(f"⚠️ 查询 {query['table']} 表失败: {e}")
        
        await cursor.close()
        return all_operations
    
    async def create_data_backup(self, table: str, record_id: int) -> Dict:
        """创建单条记录的备份"""
        cursor = await self.connection.cursor(aiomysql.DictCursor)
        
        try:
            await cursor.execute(f"SELECT * FROM {table} WHERE id = %s", (record_id,))
            record = await cursor.fetchone()
            
            if record:
                backup = {
                    'table': table,
                    'record_id': record_id,
                    'data': dict(record),
                    'backup_time': datetime.now().isoformat()
                }
                logger.info(f"✅ 已备份 {table} 表记录 ID: {record_id}")
                return backup
            else:
                logger.warning(f"⚠️ 未找到 {table} 表记录 ID: {record_id}")
                return None
                
        except Exception as e:
            logger.error(f"❌ 备份 {table} 表记录失败: {e}")
            return None
        finally:
            await cursor.close()
    
    async def restore_from_backup(self, backup: Dict) -> bool:
        """从备份恢复数据"""
        if not backup:
            return False
        
        cursor = await self.connection.cursor()
        
        try:
            # 开始事务
            await cursor.execute("START TRANSACTION")
            
            table = backup['table']
            data = backup['data']
            record_id = backup['record_id']
            
            # 构建UPDATE语句
            set_clauses = []
            values = []
            
            for key, value in data.items():
                if key != 'id':  # 跳过主键
                    set_clauses.append(f"`{key}` = %s")
                    values.append(value)
            
            if set_clauses:
                sql = f"UPDATE `{table}` SET {', '.join(set_clauses)} WHERE id = %s"
                values.append(record_id)
                
                await cursor.execute(sql, values)
                await cursor.execute("COMMIT")
                
                logger.info(f"✅ 已恢复 {table} 表记录 ID: {record_id}")
                return True
            else:
                await cursor.execute("ROLLBACK")
                logger.warning(f"⚠️ 没有可恢复的字段")
                return False
                
        except Exception as e:
            await cursor.execute("ROLLBACK")
            logger.error(f"❌ 恢复数据失败: {e}")
            return False
        finally:
            await cursor.close()
    
    async def soft_delete_rollback(self, table: str, record_id: int) -> bool:
        """软删除回滚"""
        cursor = await self.connection.cursor()
        
        try:
            # 检查表是否有软删除字段
            await cursor.execute(f"SHOW COLUMNS FROM {table} LIKE 'is_deleted'")
            has_soft_delete = await cursor.fetchone()
            
            if not has_soft_delete:
                logger.warning(f"⚠️ {table} 表没有软删除字段")
                return False
            
            # 恢复软删除的记录
            await cursor.execute("START TRANSACTION")
            
            sql = f"""
                UPDATE `{table}` 
                SET is_deleted = FALSE, deleted_at = NULL 
                WHERE id = %s
            """
            await cursor.execute(sql, (record_id,))
            
            if cursor.rowcount > 0:
                await cursor.execute("COMMIT")
                logger.info(f"✅ 已恢复软删除记录 {table} ID: {record_id}")
                return True
            else:
                await cursor.execute("ROLLBACK")
                logger.warning(f"⚠️ 未找到要恢复的记录 {table} ID: {record_id}")
                return False
                
        except Exception as e:
            await cursor.execute("ROLLBACK")
            logger.error(f"❌ 软删除回滚失败: {e}")
            return False
        finally:
            await cursor.close()
    
    async def rollback_user_operation(self, user_id: int, operation_type: str = "update") -> bool:
        """回滚用户操作"""
        logger.info(f"🔄 开始回滚用户操作: ID={user_id}, 类型={operation_type}")
        
        if operation_type == "delete":
            return await self.soft_delete_rollback("users", user_id)
        else:
            # 对于更新操作，需要从Binlog或其他方式获取原始数据
            logger.warning("⚠️ 用户更新操作回滚需要手动处理")
            return False
    
    async def rollback_course_operation(self, course_id: int, operation_type: str = "update") -> bool:
        """回滚课程操作"""
        logger.info(f"🔄 开始回滚课程操作: ID={course_id}, 类型={operation_type}")
        
        if operation_type == "delete":
            return await self.soft_delete_rollback("courses", course_id)
        else:
            logger.warning("⚠️ 课程更新操作回滚需要手动处理")
            return False
    
    async def rollback_exam_operation(self, exam_id: int) -> bool:
        """回滚考试操作"""
        logger.info(f"🔄 开始回滚考试操作: ID={exam_id}")
        
        cursor = await self.connection.cursor()
        
        try:
            await cursor.execute("START TRANSACTION")
            
            # 删除考试结果详情
            await cursor.execute("DELETE FROM exam_results WHERE exam_id = %s", (exam_id,))
            
            # 删除考试记录
            await cursor.execute("DELETE FROM exams WHERE id = %s", (exam_id,))
            
            await cursor.execute("COMMIT")
            logger.info(f"✅ 已回滚考试记录 ID: {exam_id}")
            return True
            
        except Exception as e:
            await cursor.execute("ROLLBACK")
            logger.error(f"❌ 考试回滚失败: {e}")
            return False
        finally:
            await cursor.close()
    
    async def rollback_position_operation(self, position_id: int, operation_type: str = "update") -> bool:
        """回滚岗位操作"""
        logger.info(f"🔄 开始回滚岗位操作: ID={position_id}, 类型={operation_type}")
        
        if operation_type == "delete":
            return await self.soft_delete_rollback("positions", position_id)
        else:
            logger.warning("⚠️ 岗位更新操作回滚需要手动处理")
            return False
    
    async def list_recent_changes(self, hours: int = 24):
        """列出最近的变更"""
        logger.info(f"📋 最近 {hours} 小时的数据变更:")
        
        operations = await self.get_recent_operations(hours)
        
        if not operations:
            logger.info("📝 没有找到最近的变更记录")
            return
        
        # 按类型分组显示
        by_type = {}
        for op in operations:
            op_type = op.get('type', 'unknown')
            if op_type not in by_type:
                by_type[op_type] = []
            by_type[op_type].append(op)
        
        for op_type, ops in by_type.items():
            print(f"\n🔸 {op_type.upper()} 类型变更 ({len(ops)} 条):")
            print("-" * 60)
            
            for op in ops[:10]:  # 只显示前10条
                if op_type == 'user':
                    print(f"  ID: {op['id']}, 用户名: {op['username']}, 姓名: {op['full_name']}, 时间: {op['updated_at']}")
                elif op_type == 'course':
                    print(f"  ID: {op['id']}, 课程: {op['name']}, 状态: {op['status']}, 时间: {op['updated_at']}")
                elif op_type == 'exam':
                    print(f"  ID: {op['id']}, 考试: {op['exam_name']}, 分数: {op['score']}, 时间: {op['updated_at']}")
                elif op_type == 'position':
                    print(f"  ID: {op['id']}, 岗位: {op['name']}, 状态: {op['status']}, 时间: {op['updated_at']}")
            
            if len(ops) > 10:
                print(f"  ... 还有 {len(ops) - 10} 条记录")

async def main():
    """主函数"""
    parser = argparse.ArgumentParser(description='考培练系统 - 专用数据库回滚工具')
    parser.add_argument('--list', action='store_true', help='列出最近的变更')
    parser.add_argument('--hours', type=int, default=24, help='查看最近N小时的变更 (默认24小时)')
    parser.add_argument('--rollback-user', type=int, help='回滚用户操作 (用户ID)')
    parser.add_argument('--rollback-course', type=int, help='回滚课程操作 (课程ID)')
    parser.add_argument('--rollback-exam', type=int, help='回滚考试操作 (考试ID)')
    parser.add_argument('--rollback-position', type=int, help='回滚岗位操作 (岗位ID)')
    parser.add_argument('--operation-type', choices=['update', 'delete'], default='update', help='操作类型')
    parser.add_argument('--execute', action='store_true', help='实际执行回滚')
    
    args = parser.parse_args()
    
    tool = KaopeilianRollbackTool()
    
    try:
        await tool.connect()
        
        if args.list:
            await tool.list_recent_changes(args.hours)
        
        elif args.rollback_user:
            if args.execute:
                success = await tool.rollback_user_operation(args.rollback_user, args.operation_type)
                if success:
                    logger.info("✅ 用户回滚完成")
                else:
                    logger.error("❌ 用户回滚失败")
            else:
                logger.info(f"🔍 模拟回滚用户 ID: {args.rollback_user}, 类型: {args.operation_type}")
                logger.info("使用 --execute 参数实际执行")
        
        elif args.rollback_course:
            if args.execute:
                success = await tool.rollback_course_operation(args.rollback_course, args.operation_type)
                if success:
                    logger.info("✅ 课程回滚完成")
                else:
                    logger.error("❌ 课程回滚失败")
            else:
                logger.info(f"🔍 模拟回滚课程 ID: {args.rollback_course}, 类型: {args.operation_type}")
                logger.info("使用 --execute 参数实际执行")
        
        elif args.rollback_exam:
            if args.execute:
                success = await tool.rollback_exam_operation(args.rollback_exam)
                if success:
                    logger.info("✅ 考试回滚完成")
                else:
                    logger.error("❌ 考试回滚失败")
            else:
                logger.info(f"🔍 模拟回滚考试 ID: {args.rollback_exam}")
                logger.info("使用 --execute 参数实际执行")
        
        elif args.rollback_position:
            if args.execute:
                success = await tool.rollback_position_operation(args.rollback_position, args.operation_type)
                if success:
                    logger.info("✅ 岗位回滚完成")
                else:
                    logger.error("❌ 岗位回滚失败")
            else:
                logger.info(f"🔍 模拟回滚岗位 ID: {args.rollback_position}, 类型: {args.operation_type}")
                logger.info("使用 --execute 参数实际执行")
        
        else:
            parser.print_help()
    
    except Exception as e:
        logger.error(f"❌ 程序执行异常: {e}")
    finally:
        await tool.close()

if __name__ == "__main__":
    asyncio.run(main())