from django.utils import timezone
from .models import OperationLog
from rest_framework import viewsets
from rest_framework.filters import OrderingFilter
from django_filters.rest_framework import DjangoFilterBackend
from utils.page import MyPageNumberPagination
from .serializers import OperationLogSerializer
from .filter import OperationLogFilter

class OperationLogger:
    @staticmethod
    def log_operation(request, operation_content, operation_level, operator=None, 
                     operation_result='success', module_name=None, object_id=None):
        """
        记录操作日志
        
        Args:
            request: HttpRequest对象
            operation_content: 操作内容描述
            operation_level: 操作级别
            operator: 操作者标识（用户名等），如果为None则尝试从request中获取
            operation_result: 操作结果，'success'或'failure'
            module_name: 模块名称，用于分类
            object_id: 操作对象ID
        """
        try:
            # 验证必需参数
            if not request or not operation_content or not operation_level:
                raise ValueError("缺少必需的参数: request, operation_content, operation_level")
            
            # 获取操作者标识
            operator_identifier = OperationLogger._get_operator_identifier(request, operator)
            
            # 获取模块名称（如果没有提供则从请求路径推断）
            if not module_name:
                module_name = OperationLogger._infer_module_name(request.path)
            
            # 获取客户端信息
            ip_address = OperationLogger._get_client_ip(request)
            user_agent = request.META.get('HTTP_USER_AGENT', '')[:500]  # 限制长度
            
            # 创建日志记录
            OperationLog.objects.create(
                operator=operator_identifier,
                operation_content=operation_content,
                operation_level=operation_level,
                operation_result=operation_result,
                ip_address=ip_address,
                user_agent=user_agent,
                request_method=request.method,
                request_path=request.path,
                module_name=module_name,
                object_id=object_id
            )
            
        except Exception as e:
            # 日志记录失败不应影响主要业务逻辑，但需要记录错误
            import logging
            logger = logging.getLogger(__name__)
            logger.error(f"操作日志记录失败: {str(e)}", exc_info=True)
    
    @staticmethod
    def _get_operator_identifier(request, operator):
        """获取操作者标识"""
        # 如果提供了operator参数，直接使用
        if operator is not None:
            return str(operator)
        
        # 优先尝试从request.auth获取（系统的自定义认证方式）
        if hasattr(request, 'auth') and request.auth:
            # 如果auth对象有name属性，优先使用
            if hasattr(request.auth, 'name') and request.auth.name:
                return str(request.auth.name)
            # 如果有openid属性
            elif hasattr(request.auth, 'openid') and request.auth.openid:
                return f"用户OpenID:{request.auth.openid}"
            # 如果auth本身是字符串
            elif isinstance(request.auth, str):
                return request.auth
        
        # 尝试从request.user获取（标准Django认证）
        if hasattr(request, 'user') and request.user.is_authenticated:
            # 优先使用username，如果没有则使用其他标识
            if hasattr(request.user, 'username') and request.user.username:
                return request.user.username
            elif hasattr(request.user, 'get_username'):
                username = request.user.get_username()
                if username:
                    return username
            if hasattr(request.user, 'id'):
                return f"用户ID:{request.user.id}"
        
        # 如果都没有，返回未知用户
        return "未知用户"
    
    @staticmethod
    def _infer_module_name(path):
        """从路径推断模块名称"""
        if not path:
            return 'unknown'
        
        # 移除首尾斜杠并分割路径
        path_parts = path.strip('/').split('/')
        if path_parts:
            # 使用第一个非空路径部分作为模块名
            for part in path_parts:
                if part and part not in ('api', 'v1', 'v2'):  # 跳过常见的API前缀
                    return part
        return 'unknown'
    
    @staticmethod
    def _get_client_ip(request):
        """获取客户端IP地址"""
        x_forwarded_for = request.META.get('HTTP_X_FORWARDED_FOR')
        if x_forwarded_for:
            ip = x_forwarded_for.split(',')[0].strip()
        else:
            ip = request.META.get('REMOTE_ADDR')
        return ip

# 快捷函数
def log_operation(request, operation_content, operation_level, operator=None, 
                operation_result='success', module_name=None, object_id=None):
    """快捷记录操作日志函数"""
    OperationLogger.log_operation(
        request=request, 
        operation_content=operation_content, 
        operation_level=operation_level, 
        operator=operator,
        operation_result=operation_result,
        module_name=module_name,
        object_id=object_id
    )

# 专门用于成功操作的快捷函数
def log_success_operation(request, operation_content, operation_level, operator=None, 
                         module_name=None, object_id=None):
    """记录成功操作的快捷函数"""
    log_operation(
        request=request,
        operation_content=operation_content,
        operation_level=operation_level,
        operator=operator,
        operation_result='success',
        module_name=module_name,
        object_id=object_id
    )

# 专门用于失败操作的快捷函数
def log_failure_operation(request, operation_content, operation_level, operator=None, 
                         module_name=None, object_id=None):
    """记录失败操作的快捷函数"""
    log_operation(
        request=request,
        operation_content=operation_content,
        operation_level=operation_level,
        operator=operator,
        operation_result='failure',
        module_name=module_name,
        object_id=object_id
    )


class OperationLogViewSet(viewsets.ReadOnlyModelViewSet):
    """
    操作日志 ViewSet
    只读，不支持创建、更新、删除操作
    """
    queryset = OperationLog.objects.all()
    serializer_class = OperationLogSerializer
    pagination_class = MyPageNumberPagination
    filter_backends = [DjangoFilterBackend, OrderingFilter]
    filter_class = OperationLogFilter
    ordering_fields = ['operation_time', 'id']
    ordering = ['-operation_time']  # 默认按操作时间倒序排列