from typing import Optional, List
from datetime import datetime
import json
from app.infra.db.postgresql.database import Database
from app.domain.schemas.audit import AuditLogCreate, AuditLogResponse
import logging

logger = logging.getLogger(__name__)

class AuditRepository:
    """审计日志数据访问层"""
    
    def __init__(self, db: Database):
        self.db = db
    
    async def create_log(
        self,
        user_id: Optional[int] = None,
        username: Optional[str] = None,
        action: str = "",
        resource_type: Optional[str] = None,
        resource_id: Optional[str] = None,
        ip_address: Optional[str] = None,
        user_agent: Optional[str] = None,
        request_method: Optional[str] = None,
        request_path: Optional[str] = None,
        request_data: Optional[dict] = None,
        response_status: Optional[int] = None,
        error_message: Optional[str] = None
    ) -> Optional[AuditLogResponse]:
        """
        创建审计日志
        
        Args:
            参数说明见 AuditLogCreate
            
        Returns:
            创建的审计日志对象
        """
        query = """
            INSERT INTO audit_logs (
                user_id, username, action, resource_type, resource_id,
                ip_address, user_agent, request_method, request_path,
                request_data, response_status, error_message
            )
            VALUES (
                %(user_id)s, %(username)s, %(action)s, %(resource_type)s, %(resource_id)s,
                %(ip_address)s, %(user_agent)s, %(request_method)s, %(request_path)s,
                %(request_data)s, %(response_status)s, %(error_message)s
            )
            RETURNING id, user_id, username, action, resource_type, resource_id,
                      ip_address, user_agent, request_method, request_path,
                      request_data, response_status, error_message, timestamp
        """
        
        try:
            async with self.db.get_connection() as conn:
                async with conn.cursor() as cur:
                    await cur.execute(query, {
                        'user_id': user_id,
                        'username': username,
                        'action': action,
                        'resource_type': resource_type,
                        'resource_id': resource_id,
                        'ip_address': ip_address,
                        'user_agent': user_agent,
                        'request_method': request_method,
                        'request_path': request_path,
                        'request_data': json.dumps(request_data) if request_data else None,
                        'response_status': response_status,
                        'error_message': error_message
                    })
                    row = await cur.fetchone()
                    if row:
                        return AuditLogResponse(**row)
        except Exception as e:
            logger.error(f"Error creating audit log: {e}")
            raise
        
        return None
    
    async def get_logs(
        self,
        user_id: Optional[int] = None,
        username: Optional[str] = None,
        action: Optional[str] = None,
        resource_type: Optional[str] = None,
        start_time: Optional[datetime] = None,
        end_time: Optional[datetime] = None,
        skip: int = 0,
        limit: int = 100
    ) -> List[AuditLogResponse]:
        """
        查询审计日志
        
        Args:
            user_id: 用户ID过滤
            username: 用户名过滤
            action: 操作类型过滤
            resource_type: 资源类型过滤
            start_time: 开始时间
            end_time: 结束时间
            skip: 跳过记录数
            limit: 限制记录数
            
        Returns:
            审计日志列表
        """
        # 构建动态查询
        conditions = []
        params = {'skip': skip, 'limit': limit}
        
        if user_id is not None:
            conditions.append("user_id = %(user_id)s")
            params['user_id'] = user_id
        
        if username:
            conditions.append("username = %(username)s")
            params['username'] = username
        
        if action:
            conditions.append("action = %(action)s")
            params['action'] = action
        
        if resource_type:
            conditions.append("resource_type = %(resource_type)s")
            params['resource_type'] = resource_type
        
        if start_time:
            conditions.append("timestamp >= %(start_time)s")
            params['start_time'] = start_time
        
        if end_time:
            conditions.append("timestamp <= %(end_time)s")
            params['end_time'] = end_time
        
        where_clause = f"WHERE {' AND '.join(conditions)}" if conditions else ""
        
        query = f"""
            SELECT id, user_id, username, action, resource_type, resource_id,
                   ip_address, user_agent, request_method, request_path,
                   request_data, response_status, error_message, timestamp
            FROM audit_logs
            {where_clause}
            ORDER BY timestamp DESC
            LIMIT %(limit)s OFFSET %(skip)s
        """
        
        try:
            async with self.db.get_connection() as conn:
                async with conn.cursor() as cur:
                    await cur.execute(query, params)
                    rows = await cur.fetchall()
                    return [AuditLogResponse(**row) for row in rows]
        except Exception as e:
            logger.error(f"Error querying audit logs: {e}")
            raise
    
    async def get_log_count(
        self,
        user_id: Optional[int] = None,
        username: Optional[str] = None,
        action: Optional[str] = None,
        resource_type: Optional[str] = None,
        start_time: Optional[datetime] = None,
        end_time: Optional[datetime] = None
    ) -> int:
        """
        获取审计日志数量
        
        Args:
            参数同 get_logs
            
        Returns:
            日志总数
        """
        conditions = []
        params = {}
        
        if user_id is not None:
            conditions.append("user_id = %(user_id)s")
            params['user_id'] = user_id
        
        if username:
            conditions.append("username = %(username)s")
            params['username'] = username
        
        if action:
            conditions.append("action = %(action)s")
            params['action'] = action
        
        if resource_type:
            conditions.append("resource_type = %(resource_type)s")
            params['resource_type'] = resource_type
        
        if start_time:
            conditions.append("timestamp >= %(start_time)s")
            params['start_time'] = start_time
        
        if end_time:
            conditions.append("timestamp <= %(end_time)s")
            params['end_time'] = end_time
        
        where_clause = f"WHERE {' AND '.join(conditions)}" if conditions else ""
        
        query = f"""
            SELECT COUNT(*) as count
            FROM audit_logs
            {where_clause}
        """
        
        try:
            async with self.db.get_connection() as conn:
                async with conn.cursor() as cur:
                    await cur.execute(query, params)
                    result = await cur.fetchone()
                    return result['count'] if result else 0
        except Exception as e:
            logger.error(f"Error counting audit logs: {e}")
            return 0