from pydantic import BaseModel
from datetime import datetime
from typing import Optional
from enum import Enum


class PriorityLevel(str, Enum):
    LOW = "low"
    MEDIUM = "medium"
    HIGH = "high"


class TodoBase(BaseModel):
    title: str
    description: Optional[str] = None
    completed: bool = False
    priority: PriorityLevel = PriorityLevel.MEDIUM


class TodoCreate(TodoBase):
    pass


class TodoUpdate(BaseModel):
    title: Optional[str] = None
    description: Optional[str] = None
    completed: Optional[bool] = None
    priority: Optional[PriorityLevel] = None


class TodoResponse(TodoBase):
    id: int
    created_at: datetime
    updated_at: datetime

    class Config:
        orm_mode = True
        from_attributes = True