#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""
微信用户表迁移脚本
创建微信用户表和相关索引
"""

import os
import sys
import logging
import psycopg2
from psycopg2 import sql

# 添加项目根目录到Python路径
sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), '../..')))

from app.config.config import config, current_env

# 获取配置
app_config = config[current_env]

# 配置日志
log_level_name = getattr(app_config, 'LOG_LEVEL', 'INFO')
log_level = getattr(logging, log_level_name)
log_format = getattr(app_config, 'LOG_FORMAT', '%(asctime)s - %(name)s - %(levelname)s - %(message)s')

logging.basicConfig(
    level=log_level,
    format=log_format
)
logger = logging.getLogger(__name__)


def get_database_connection():
    """
    获取数据库连接
    
    Returns:
        psycopg2.connection: 数据库连接对象
    """
    try:
        # 从配置中获取数据库连接信息
        db_config = {
            'host': app_config.PG_HOST,
            'port': app_config.PG_PORT,
            'database': app_config.PG_DATABASE,
            'user': app_config.PG_USERNAME,
            'password': app_config.PG_PASSWORD
        }
        
        connection = psycopg2.connect(**db_config)
        logger.info("成功连接到数据库")
        return connection
        
    except Exception as e:
        logger.error(f"连接数据库失败: {str(e)}")
        raise


def check_table_exists(connection, table_name, schema='public'):
    """
    检查表是否存在
    
    Args:
        connection: 数据库连接
        table_name (str): 表名
        schema (str): 模式名，默认为public
        
    Returns:
        bool: 表存在返回True，否则返回False
    """
    try:
        with connection.cursor() as cursor:
            cursor.execute("""
                SELECT EXISTS (
                    SELECT FROM information_schema.tables 
                    WHERE table_schema = %s AND table_name = %s
                );
            """, (schema, table_name))
            
            result = cursor.fetchone()
            return result[0] if result else False
            
    except Exception as e:
        logger.error(f"检查表是否存在时发生错误: {str(e)}")
        return False


def create_wechat_users_table(connection):
    """
    创建微信用户表
    
    Args:
        connection: 数据库连接
        
    Returns:
        bool: 创建成功返回True，否则返回False
    """
    try:
        # 读取SQL DDL文件
        sql_file_path = os.path.join(os.path.dirname(__file__), '../../database/create_wechat_users.sql')
        
        if not os.path.exists(sql_file_path):
            logger.error(f"SQL文件不存在: {sql_file_path}")
            return False
        
        with open(sql_file_path, 'r', encoding='utf-8') as file:
            sql_content = file.read()
        
        with connection.cursor() as cursor:
            # 执行SQL脚本
            cursor.execute(sql_content)
            connection.commit()
            
        logger.info("微信用户表创建成功")
        return True
        
    except Exception as e:
        logger.error(f"创建微信用户表失败: {str(e)}")
        connection.rollback()
        return False


def migrate_wechat_users():
    """
    执行微信用户表迁移
    
    Returns:
        bool: 迁移成功返回True，否则返回False
    """
    connection = None
    
    try:
        # 获取数据库连接
        connection = get_database_connection()
        
        # 检查表是否已存在
        if check_table_exists(connection, 'wechat_users'):
            logger.warning("微信用户表已存在，跳过创建")
            return True
        
        logger.info("开始创建微信用户表...")
        
        # 创建微信用户表
        if create_wechat_users_table(connection):
            logger.info("微信用户表迁移完成")
            return True
        else:
            logger.error("微信用户表迁移失败")
            return False
            
    except Exception as e:
        logger.error(f"迁移过程中发生错误: {str(e)}")
        return False
        
    finally:
        if connection:
            connection.close()
            logger.info("数据库连接已关闭")


def rollback_wechat_users():
    """
    回滚微信用户表迁移（删除表）
    
    Returns:
        bool: 回滚成功返回True，否则返回False
    """
    connection = None
    
    try:
        # 获取数据库连接
        connection = get_database_connection()
        
        # 检查表是否存在
        if not check_table_exists(connection, 'wechat_users'):
            logger.warning("微信用户表不存在，无需回滚")
            return True
        
        logger.info("开始回滚微信用户表...")
        
        with connection.cursor() as cursor:
            # 删除表
            cursor.execute("DROP TABLE IF EXISTS public.wechat_users CASCADE;")
            connection.commit()
            
        logger.info("微信用户表回滚完成")
        return True
        
    except Exception as e:
        logger.error(f"回滚过程中发生错误: {str(e)}")
        if connection:
            connection.rollback()
        return False
        
    finally:
        if connection:
            connection.close()
            logger.info("数据库连接已关闭")


def main():
    """
    主函数，根据命令行参数执行相应操作
    """
    import argparse
    
    parser = argparse.ArgumentParser(description='微信用户表迁移脚本')
    parser.add_argument('--action', choices=['migrate', 'rollback'], default='migrate',
                        help='执行的操作：migrate（迁移）或 rollback（回滚）')
    
    args = parser.parse_args()
    
    if args.action == 'migrate':
        logger.info("开始执行微信用户表迁移...")
        success = migrate_wechat_users()
    elif args.action == 'rollback':
        logger.info("开始执行微信用户表回滚...")
        success = rollback_wechat_users()
    else:
        logger.error("未知的操作类型")
        sys.exit(1)
    
    if success:
        logger.info("操作完成")
        sys.exit(0)
    else:
        logger.error("操作失败")
        sys.exit(1)


if __name__ == "__main__":
    main()