from enum import StrEnum
from typing import Annotated

from pydantic import BaseModel, StringConstraints, field_validator


class Status(StrEnum):
    TO_READ = "to-read"
    READING = "reading"
    DONE = "done"


class Book(BaseModel):
    id: int
    title: str
    author: str | None = None
    status: Status


class BookCreate(BaseModel):
    title: Annotated[str, StringConstraints(strip_whitespace=True, min_length=1, max_length=200)]
    author: Annotated[str, StringConstraints(strip_whitespace=True, max_length=200)] | None = None
    status: Status = Status.TO_READ

    @field_validator("author")
    @classmethod
    def blank_author_is_none(cls, value: str | None) -> str | None:
        return value or None


class BookStatusUpdate(BaseModel):
    status: Status


class BookStats(BaseModel):
    total: int
    by_status: dict[Status, int]