from calculus.remote_2 import RemoteCalculationFactory

from twisted.test import proto_helpers
from twisted.trial import unittest


class RemoteCalculationTestCase(unittest.TestCase):
    def setUp(self):
        factory = RemoteCalculationFactory()
        self.proto = factory.buildProtocol(("127.0.0.1", 0))
        self.tr = proto_helpers.StringTransport()
        self.proto.makeConnection(self.tr)

    def _test(self, operation, a, b, expected):
        self.proto.dataReceived(f"{operation} {a} {b}\r\n".encode())
        self.assertEqual(int(self.tr.value()), expected)

    def test_add(self):
        return self._test("add", 7, 6, 13)

    def test_subtract(self):
        return self._test("subtract", 82, 78, 4)

    def test_multiply(self):
        return self._test("multiply", 2, 8, 16)

    def test_divide(self):
        return self._test("divide", 14, 3, 4)

    def test_invalidParameters(self):
        self.proto.dataReceived(b"add foo bar\r\n")
        self.assertEqual(self.tr.value(), b"error\r\n")
        errors = self.flushLoggedErrors(TypeError)
        self.assertEqual(len(errors), 1)