from datetime import datetime
from typing import Optional

from pydantic import BaseModel


class TodoBase(BaseModel):
    """Base schema for Todo"""

    title: str
    description: Optional[str] = None
    completed: bool = False


class TodoCreate(TodoBase):
    """Schema for creating a new Todo"""

    pass


class TodoUpdate(BaseModel):
    """Schema for updating a Todo (all fields optional)"""

    title: Optional[str] = None
    description: Optional[str] = None
    completed: Optional[bool] = None


class TodoInDB(TodoBase):
    """Schema for Todo stored in DB"""

    id: int
    created_at: datetime
    updated_at: datetime

    class Config:
        """Configure pydantic model"""

        from_attributes = True


class TodoResponse(TodoInDB):
    """Schema for Todo response"""

    pass