"""Lambda test module."""
import pytest
from src import app
import fixtures


@pytest.fixture
def transform_spy(mocker):
    """Create a spy for the transform function."""
    return mocker.spy(app, 'transform')


def test_handler(kafka_mock, transform_spy):
    """Test handler function."""
    message1 = {'message': '1'}
    message2 = {'message': '2'}
    result = app.handler({'Records': [message1, message2]}, None)
    kafka_mock.assert_call_count('produce', 2)
    assert transform_spy.called
    assert result == {'status': 'OK'}


@pytest.mark.parametrize('lambda_message, camel_connector_message, ignored_keys', [
    (
        fixtures.LAMBDA_INSERT_MESSAGE,
        fixtures.CAMEL_CONNECTOR_INSERT_MESSAGE,
        {'oldImage'}
    ),
    (
        fixtures.LAMBDA_MODIFY_MESSAGE,
        fixtures.CAMEL_CONNECTOR_MODIFY_MESSAGE,
        {}
    ),
    (
        fixtures.LAMBDA_REMOVE_MESSAGE,
        fixtures.CAMEL_CONNECTOR_REMOVE_MESSAGE,
        {'newImage'}
    ),
])
def test_transform(lambda_message, camel_connector_message, ignored_keys):
    """Test transform function.

    The test uses real messages generated by the DynamoDB Streams.
    The lambda messages is the input of this lambda function, and the camel connector
    message is the way how Camel connector produce messages to Kafka.
    """
    transformed_lambda_message = app.transform(lambda_message)
    result = is_subset(
        camel_connector_message, transformed_lambda_message,
        ignore_keys=ignored_keys)
    assert result


def is_subset(dict1, dict2, ignore_keys):
    """Recursively check that all keys and values in dict1 exist in dict2 (except the ignore keys)."""
    if isinstance(dict1, dict) and isinstance(dict2, dict):
        for key in dict1:
            if key in ignore_keys:
                continue
            if key not in dict2 or not is_subset(dict1[key], dict2[key], ignore_keys):
                return False
        return True
    elif isinstance(dict1, list) and isinstance(dict2, list):
        # Ensure all elements in dict1 exist in dict2 (order-independent)
        return all(any(is_subset(v1, v2, ignore_keys) for v2 in dict2) for v1 in dict1)
    else:
        return dict1 == dict2