from typing import Optional

from fastapi import FastAPI
from pydantic import BaseModel, Field

app = FastAPI()


class Item(BaseModel):
    id: Optional[int] = None
    name: str = Field(description="The name of the item", regex="^[a-zA-Z0-9]*$")
    price: float
    is_offer: Optional[bool] = None


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Optional[str] = None):
    return {"item_id": item_id, "q": q}


@app.post("/items")
def create_item(item: Item) -> Item:
    return item