import random
from abc import ABC, abstractmethod
from typing import Any

from pydantic import UUID4, BaseModel

from secretsanta.settings import Config, get_config


class Group(BaseModel):
    uuid: UUID4
    participants: list[str]
    pairs: dict[str, str] | None = None

    @staticmethod
    def pair(names: list[str]) -> dict[str, str]:
        names_copy = names[:]
        random.shuffle(names_copy)

        pairings = {}
        for i, name in enumerate(names):
            pair = names_copy[i]
            while pair == name:
                random.shuffle(names_copy)
                pair = names_copy[i]

            pairings[name] = pair

        return pairings


class IRepo(ABC):
    @abstractmethod
    async def get(self, group_uuid: str) -> Group | None:
        ...  # pragma: no cover

    @abstractmethod
    async def create(self, group: Group) -> Group:
        ...  # pragma: no cover


class IService(ABC):
    def __init__(self, repo: IRepo, config: Config | None = None):
        self.repo = repo
        self.config = config or get_config()

    @abstractmethod
    async def run(self, *args, **kwargs) -> Any:
        ...  # pragma: no cover