"""
统一返回结果类 - 对齐JAVA Result

@author: {{ author }}
@date: {{ date }}
"""
from typing import TypeVar, Generic, Optional, Any
from pydantic import BaseModel, Field
from datetime import datetime
import time

T = TypeVar('T')

class Result(BaseModel, Generic[T]):
    """接口返回数据格式 - 对齐JAVA Result<T>"""
    success: bool = Field(True, description="成功标志")
    message: str = Field("", description="返回处理消息")
    code: int = Field(0, description="返回代码, 0=成功, 500=错误")
    result: Optional[T] = Field(None, description="返回数据对象")
    timestamp: int = Field(default_factory=lambda: int(time.time() * 1000), description="时间戳")

    @staticmethod
    def OK(data: Any = None, message: str = "") -> dict:
        """成功返回"""
        return {
            "success": True,
            "message": message,
            "code": 200,
            "result": data,
            "timestamp": int(time.time() * 1000)
        }

    @staticmethod
    def error(message: str, code: int = 500) -> dict:
        """错误返回"""
        return {
            "success": False,
            "message": message,
            "code": code,
            "result": None,
            "timestamp": int(time.time() * 1000)
        }

    @staticmethod
    def noauth(message: str = "无权限访问") -> dict:
        """无权限返回"""
        return {
            "success": False,
            "message": message,
            "code": 210,
            "result": None,
            "timestamp": int(time.time() * 1000)
        }


def to_camel_case(name: str) -> str:
    """snake_case 转 camelCase"""
    if not name or "_" not in name:
        return name
    parts = name.split("_")
    return parts[0].lower() + "".join(p.capitalize() for p in parts[1:] if p)


def to_camel_dict(obj) -> dict:
    """把 SQLAlchemy 模型实例（或任意对象）转成驼峰 key 的字典。

    只提取 __table__.columns 中声明的列，避免泄露 _sa_instance_state 等
    SQLAlchemy 内部状态字段。数据库列名是 snake_case，输出 key 转成驼峰。
    """
    if obj is None:
        return None

    if hasattr(obj, "__table__"):
        keys = [c.name for c in obj.__table__.columns]
        result = {}
        for k in keys:
            result[to_camel_case(k)] = getattr(obj, k, None)
        return result

    if isinstance(obj, dict):
        return {to_camel_case(k): v for k, v in obj.items()}

    if hasattr(obj, "__dict__"):
        return {to_camel_case(k): v for k, v in obj.__dict__.items() if not k.startswith("_")}

    return obj