# ------------------------------------
# Copyright (c) Microsoft Corporation.
# Licensed under the MIT License.
# ------------------------------------
try:
    from unittest.mock import Mock
except ImportError:  # python < 3.3
    from mock import Mock  # type: ignore

from azure.core.credentials import AccessToken
from azure.core.exceptions import ClientAuthenticationError
from azure.identity import (
    ChainedTokenCredential,
    ClientSecretCredential,
    CredentialUnavailableError,
)
import pytest


def test_error_message():
    first_error = "first_error"
    first_credential = Mock(
        spec=ClientSecretCredential, get_token=Mock(side_effect=CredentialUnavailableError(first_error))
    )
    second_error = "second_error"
    second_credential = Mock(
        name="second_credential", get_token=Mock(side_effect=ClientAuthenticationError(second_error))
    )

    with pytest.raises(ClientAuthenticationError) as ex:
        ChainedTokenCredential(first_credential, second_credential).get_token("scope")

    assert "ClientSecretCredential" in ex.value.message
    assert first_error in ex.value.message
    assert second_error in ex.value.message


def test_attempts_all_credentials():
    expected_token = AccessToken("expected_token", 0)

    credentials = [
        Mock(get_token=Mock(side_effect=CredentialUnavailableError(message=""))),
        Mock(get_token=Mock(side_effect=CredentialUnavailableError(message=""))),
        Mock(get_token=Mock(return_value=expected_token)),
    ]

    token = ChainedTokenCredential(*credentials).get_token("scope")
    assert token is expected_token

    for credential in credentials:
        assert credential.get_token.call_count == 1


def test_raises_for_unexpected_error():
    """the chain should not continue after an unexpected error (i.e. anything but CredentialUnavailableError)"""

    expected_message = "it can't be done"

    credentials = [
        Mock(get_token=Mock(side_effect=CredentialUnavailableError(message=""))),
        Mock(get_token=Mock(side_effect=ValueError(expected_message))),
        Mock(get_token=Mock(return_value=AccessToken("**", 42))),
    ]

    with pytest.raises(ClientAuthenticationError) as ex:
        ChainedTokenCredential(*credentials).get_token("scope")

    assert expected_message in ex.value.message
    assert credentials[-1].get_token.call_count == 0


def test_returns_first_token():
    expected_token = Mock()
    first_credential = Mock(get_token=lambda _: expected_token)
    second_credential = Mock(get_token=Mock())

    aggregate = ChainedTokenCredential(first_credential, second_credential)
    credential = aggregate.get_token("scope")

    assert credential is expected_token
    assert second_credential.get_token.call_count == 0