import pytest

from ai_platform.platform.application.admin_users import (
    AdminUserAlreadyExists,
    AdminUserUseCases,
)


class Repository:
    def __init__(self, *, existing: bool = False, conflict_on_create: bool = False) -> None:
        self.existing = existing
        self.conflict_on_create = conflict_on_create
        self.created: tuple[str, str] | None = None

    async def exists(self, email: str) -> bool:
        assert email == "admin@example.invalid"
        return self.existing

    async def create(self, email: str, password_hash: str) -> None:
        if self.conflict_on_create:
            raise AdminUserAlreadyExists
        self.created = (email, password_hash)


class Transaction:
    def __init__(self) -> None:
        self.commits = 0
        self.rollbacks = 0

    async def commit(self) -> None:
        self.commits += 1

    async def rollback(self) -> None:
        self.rollbacks += 1


def make_use_case(repository: Repository, transaction: Transaction) -> AdminUserUseCases:
    return AdminUserUseCases(
        repository=repository,
        hash_password=lambda password: f"hashed:{password}",
        commit=transaction.commit,
        rollback=transaction.rollback,
    )


async def test_create_normalizes_email_hashes_password_and_commits():
    repository = Repository()
    transaction = Transaction()
    use_case = make_use_case(repository, transaction)

    await use_case.create(" Admin@Example.Invalid ", "test-password")

    assert repository.created == ("admin@example.invalid", "hashed:test-password")
    assert transaction.commits == 1
    assert transaction.rollbacks == 0


async def test_existing_admin_is_rejected_without_mutation():
    repository = Repository(existing=True)
    transaction = Transaction()
    use_case = make_use_case(repository, transaction)

    with pytest.raises(AdminUserAlreadyExists):
        await use_case.create("admin@example.invalid", "test-password")

    assert repository.created is None
    assert transaction.commits == 0
    assert transaction.rollbacks == 0


async def test_concurrent_duplicate_admin_creation_rolls_back():
    repository = Repository(conflict_on_create=True)
    transaction = Transaction()
    use_case = make_use_case(repository, transaction)

    with pytest.raises(AdminUserAlreadyExists):
        await use_case.create("admin@example.invalid", "test-password")

    assert transaction.commits == 0
    assert transaction.rollbacks == 1