from pydantic import BaseModel, EmailStr

from typing import Optional
from datetime import datetime

class User(BaseModel):
    username: str
    email: EmailStr
    password: str

class TokenData(BaseModel):
    username: Optional[str] = None

class Token(BaseModel):
    access_token: str
    token_type: str

class FileUpload(BaseModel):
    filename: str
    content: list[dict]
    created_at: Optional[datetime] = None
    updated_at: Optional[datetime] = None

class ChatMessage(BaseModel):
    message: str
    timestamp: datetime
    sender: str