from pydantic import BaseModel
from typing import List, Optional
from datetime import datetime

class MessageBase(BaseModel):
    role: str
    content: str

class MessageOut(MessageBase):
    id: int
    created_at: datetime

    class Config:
        orm_mode = True


class ChatBase(BaseModel):
    title: str

class ChatOut(ChatBase):
    id: int
    messages: List[MessageOut] = []

    class Config:
        orm_mode = True


class UserOut(BaseModel):
    id: int
    telegram_id: str
    username: Optional[str]
    chats: List[ChatOut] = []

    class Config:
        orm_mode = True