from __future__ import annotations

from dataclasses import dataclass

import cloud.auth as auth_module
import pytest
from cloud.auth import (
    BearerCredential,
    ConfiguredBearerAuthProvider,
    HostIdentityMismatchError,
    HostPrincipalRequiredError,
    NullAuthProvider,
)


@dataclass
class _Request:
    headers: dict[str, str]


def test_configured_bearer_auth_returns_identity_and_scopes() -> None:
    provider = ConfiguredBearerAuthProvider(
        [
            BearerCredential(
                principal_id="integrator-a",
                token="secret-a",
                scopes=frozenset({"tasks:submit", "tasks:read"}),
            )
        ]
    )

    principal = provider.authenticate(
        _Request(headers={"authorization": "Bearer secret-a"})
    )

    assert principal is not None
    assert principal.id == "integrator-a"
    assert principal.scopes == frozenset({"tasks:submit", "tasks:read"})


def test_missing_malformed_or_invalid_bearer_token_is_rejected() -> None:
    provider = ConfiguredBearerAuthProvider(
        [BearerCredential(principal_id="integrator", token="valid-token")]
    )

    assert provider.authenticate(_Request(headers={})) is None
    assert (
        provider.authenticate(_Request(headers={"authorization": "Basic value"}))
        is None
    )
    assert (
        provider.authenticate(_Request(headers={"authorization": "Bearer invalid"}))
        is None
    )


def test_bearer_verification_compares_every_configured_digest(monkeypatch) -> None:
    comparisons: list[tuple[bytes, bytes]] = []
    original_compare_digest = auth_module.compare_digest

    def recording_compare_digest(left: bytes, right: bytes) -> bool:
        comparisons.append((left, right))
        return original_compare_digest(left, right)

    monkeypatch.setattr(auth_module, "compare_digest", recording_compare_digest)
    provider = ConfiguredBearerAuthProvider(
        [
            BearerCredential(principal_id="first", token="match"),
            BearerCredential(principal_id="second", token="other"),
        ]
    )

    principal = provider.authenticate(
        _Request(headers={"authorization": "Bearer match"})
    )

    assert principal is not None
    assert principal.id == "first"
    assert len(comparisons) == 2
    assert all(len(left) == len(right) == 32 for left, right in comparisons)


def test_credential_representations_do_not_expose_token() -> None:
    credential = BearerCredential(principal_id="integrator", token="top-secret")
    provider = ConfiguredBearerAuthProvider([credential])

    assert "top-secret" not in repr(credential)
    assert "top-secret" not in repr(provider.__dict__)


def test_null_auth_provider_is_explicitly_unrestricted() -> None:
    principal = NullAuthProvider().authenticate(_Request(headers={}))

    assert principal is not None
    assert principal.id == "anonymous"
    assert principal.scopes == frozenset({"*"})


def test_host_credential_authenticates_as_one_bound_host() -> None:
    provider = ConfiguredBearerAuthProvider(
        [
            BearerCredential(
                principal_id="host-agent-a",
                token="host-secret",
                scopes=frozenset({"host:agent"}),
                host_id="host-a",
            )
        ]
    )

    principal = provider.authenticate(
        _Request(headers={"authorization": "Bearer host-secret"})
    )

    assert principal is not None
    assert principal.host_id == "host-a"
    principal.require_host("host-a")


def test_host_principal_rejects_cross_host_operation() -> None:
    provider = ConfiguredBearerAuthProvider(
        [
            BearerCredential(
                principal_id="host-agent-a",
                token="host-secret",
                host_id="host-a",
            )
        ]
    )
    principal = provider.authenticate(
        _Request(headers={"authorization": "Bearer host-secret"})
    )

    assert principal is not None
    with pytest.raises(HostIdentityMismatchError):
        principal.require_host("host-b")


def test_public_principal_cannot_act_as_host() -> None:
    provider = ConfiguredBearerAuthProvider(
        [BearerCredential(principal_id="integrator", token="public-secret")]
    )
    principal = provider.authenticate(
        _Request(headers={"authorization": "Bearer public-secret"})
    )

    assert principal is not None
    with pytest.raises(HostPrincipalRequiredError):
        principal.require_host("host-a")