import re
from typing import Optional

from fastapi import HTTPException, status
from sqlalchemy.ext.asyncio import AsyncSession

from app.application.roles_repository import RolesRepository
from app.application.users_repository import UsersRepository
from app.domain.entities.change_password import ChangePasswordEntity
from app.domain.entities.register import RegisterEntity
from app.domain.entities.user import UserEntity
from app.domain.models import User
from app.infrastructure.roles_service import RolesService


class UsersService:
    def __init__(self, db: AsyncSession):
        self.users_repository = UsersRepository(db)
        self.roles_repository = RolesRepository(db)

    async def get_by_id(self, user_id: int) -> Optional[UserEntity]:
        user = await self.users_repository.get_by_id(user_id)
        if not user:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail='Пользователь не найден',
            )

        user_entity = self.model_to_entity(user)
        user_entity.role = RolesService.model_to_entity(user.role)

        return user_entity

    async def get_all_users(self) -> list[UserEntity]:
        users = await self.users_repository.get_all()
        response = []

        for user in users:
            user_entity = self.model_to_entity(user)
            user_entity.role = RolesService.model_to_entity(user.role)
            response.append(user_entity)

        return response

    async def change_password(self, data: ChangePasswordEntity, current_user_id: int) -> Optional[UserEntity]:
        user = await self.users_repository.get_by_id(data.user_id)
        if not user:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail='Пользователь не найден',
            )

        current_user = await self.users_repository.get_by_id(current_user_id)
        if not current_user:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail='Пользователь не найден',
            )

        if user.id != current_user.id and current_user.role.title != 'Администратор':
            raise HTTPException(
                status_code=status.HTTP_403_FORBIDDEN,
                detail='Доступ запрещен',
            )

        if not user.check_password(data.current_password):
            raise HTTPException(
                status_code=status.HTTP_403_FORBIDDEN,
                detail='Доступ запрещен',
            )

        if data.new_password != data.confirm_password:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail='Пароли не совпали',
            )

        user.set_password(data.confirm_password)

        user = await self.users_repository.update(user)

        return self.model_to_entity(user)

    async def register_user(self, register_entity: RegisterEntity) -> Optional[UserEntity]:
        role = await self.roles_repository.get_by_id(register_entity.role_id)
        if not role:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail='Роль с таким ID не найдена'
            )

        user = await self.users_repository.get_by_login(register_entity.login)
        if user:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail='Пользователь с таким логином уже существует'
            )

        if register_entity.password != register_entity.confirm_password:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail='Пароли не совпали',
            )

        if not self.is_strong_password(register_entity.confirm_password):
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail="Пароль слишком слабый. Пароль должен содержать не менее 8 символов, включая хотя бы одну букву и одну цифру и один специальный символ."
            )

        user_model = User(
            first_name=register_entity.first_name,
            last_name=register_entity.last_name,
            patronymic=register_entity.patronymic,
            login=register_entity.login,
            role_id=register_entity.role_id,
        )
        user_model.set_password(register_entity.confirm_password)

        created_user = await self.users_repository.create(user_model)

        return UserEntity(
            id=created_user.id,
            first_name=created_user.first_name,
            last_name=created_user.last_name,
            patronymic=created_user.patronymic,
            login=created_user.login,
            role_id=created_user.role_id,
        )

    async def update_user(self, user: UserEntity, user_id: int, current_user_id: int) -> Optional[UserEntity]:
        user_model = await self.users_repository.get_by_id(user_id)
        if not user_model:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail='Пользователь не найден',
            )

        current_user = await self.users_repository.get_by_id(current_user_id)
        if not current_user:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail='Пользователь не найден',
            )

        if user.id != current_user.id and current_user.role.title != 'Администратор':
            raise HTTPException(
                status_code=status.HTTP_403_FORBIDDEN,
                detail='Доступ запрещен',
            )

        user_model.first_name = user.first_name
        user_model.last_name = user.last_name
        user_model.patronymic = user.patronymic

        user_model = await self.users_repository.update(user_model)

        return self.model_to_entity(user_model)

    @staticmethod
    def is_strong_password(password: str) -> bool:
        if len(password) < 8:
            return False

        if not re.search(r"[A-Z]", password):
            return False

        if not re.search(r"[a-z]", password):
            return False

        if not re.search(r"\d", password):
            return False

        if not re.search(r"[!@#$%^&*(),.?\":{}|<>]", password):
            return False

        return True

    @staticmethod
    def entity_to_model(user: UserEntity) -> User:
        user_model = User(
            first_name=user.first_name,
            last_name=user.last_name,
            patronymic=user.patronymic,
            login=user.login,
        )

        if user.id is not None:
            user_model.id = user.id

        return user_model

    @staticmethod
    def model_to_entity(user: User) -> UserEntity:
        return UserEntity(
            id=user.id,
            first_name=user.first_name,
            last_name=user.last_name,
            patronymic=user.patronymic,
            login=user.login,
            role_id=user.role_id,
        )