"""Lambda test module."""
import hashlib
import json
from unittest.mock import MagicMock
from unittest.mock import patch

from kafka.errors import UnknownTopicOrPartitionError
import pytest

from src import app  # noqa:I202
from src import consts  # noqa:I202


HEADERS = {'content-type': 'application/json'}


@patch('src.app.producer')
@patch('src.app.uuid')
def test_handler_success(
        uuid_mock, producer_mock, test_event, test_transformed_event):
    """Test handler function successful."""
    expected_topic_name = 'test_topic'
    expected_uuid = 'uuid-uuid'
    uuid_mock.uuid4 = MagicMock(return_value=expected_uuid)

    result = app.handler(test_event, None)

    expected_data = test_transformed_event
    expected_id = hashlib.sha256(
        ('test@test.comtestartist' + consts.SALT).encode()
    ).hexdigest().encode()
    expected_headers = [
        (consts.ID_HEADER, expected_id),
        (consts.CORRELATION_ID_HEADER, expected_uuid.encode())
    ]
    expected_body = json.dumps({'response': 'ok'})

    actual_topic, actual_data = producer_mock.send.call_args.args
    actual_headers = producer_mock.send.call_args.kwargs['headers']
    actual_data = json.loads(actual_data)

    producer_mock.send.assert_called()
    assert actual_topic == expected_topic_name
    assert actual_data == expected_data
    assert actual_headers == expected_headers
    producer_mock.flush.assert_called()
    assert result == {
        'body': expected_body, 'headers': HEADERS, 'statusCode': 200}


@patch('src.app.producer')
def test_handler_no_body(producer_mock, test_event):
    """Test handler function fails if the body is empty."""
    test_event['body'] = ''

    result = app.handler(test_event, None)

    producer_mock.send.assert_not_called()
    expected_body = json.dumps({'response': consts.ERROR_EMPTY_BODY})
    assert result == {
        'body': expected_body, 'headers': HEADERS, 'statusCode': 400}


@patch('src.app.producer')
def test_handler_required_field(producer_mock, test_event_no_required_field):
    """Test handler function fails if the body is empty."""
    result = app.handler(test_event_no_required_field, None)
    producer_mock.send.assert_not_called()
    expected_body = json.dumps(
        {'response': {'email': ['Missing data for required field.']}})
    assert result == {
        'body': expected_body, 'headers': HEADERS, 'statusCode': 400}


@patch('src.app.producer')
def test_handler_malformed_json(producer_mock, test_event):
    """Test handler function fails if the payload is malformed."""
    # remove the closing curly bracket from the payload json
    test_event['body'] = test_event['body'][:-1]

    result = app.handler(test_event, None)

    producer_mock.send.assert_not_called()
    expected_error = "Expecting ',' delimiter: line 1 column 435 (char 434)"
    expected_body = json.dumps({'response': expected_error})
    assert result == {
        'body': expected_body, 'headers': HEADERS, 'statusCode': 400}


@patch('src.app.producer')
def test_handler_producer_failure(producer_mock, test_event):
    """Test handler function fails because of kafka error."""
    producer_mock.send = MagicMock(side_effect=UnknownTopicOrPartitionError)

    result = app.handler(test_event, None)

    producer_mock.send.assert_called()
    expected_error = '[Error 3] UnknownTopicOrPartitionError'
    expected_body = json.dumps({'response': expected_error})
    assert result == {
        'body': expected_body, 'headers': HEADERS, 'statusCode': 500}


@pytest.mark.parametrize(
    'values,same_id', [
        (
            [
                ('test@test.com', 'limp bizkit'),
                ('test@test.com', 'Limp Bizkit'),
                ('Test@tesT.com', 'Limp bizkit')
            ],
            True
        ),
        (
            [
                ('test@test.com', 'firstname'),
                ('hello@abc.com', 'othername'),
            ],
            False
        ),
    ]
)
@patch('src.app.producer')
def test_generate_salesforce_id(producer_mock, values, same_id):
    """Test generation of salesforce ID for different values."""
    hashes = []
    for (email, artist_name) in values:
        hashes.append(app.generate_salesforce_id(email, artist_name))

    if same_id:
        assert len(set(hashes)) == 1
    else:
        assert len(set(hashes)) == len(hashes)