import unittest
import yaml
import config.loopback as loopback

class TestLoopbackMethods(unittest.TestCase):
    def setUp(self):
        with open("unittest/test_loopback.yaml", "r") as f:
            self.cfg = yaml.load(f, Loader = yaml.FullLoader)

    def test_get_by_lcp_name(self):
        ifname, iface = loopback.get_by_lcp_name(self.cfg, "loop56789012345")
        self.assertIsNotNone(iface)
        self.assertEqual("loop1", ifname)

        ifname, iface = loopback.get_by_lcp_name(self.cfg, "lcp-noexist")
        self.assertIsNone(iface)
        self.assertIsNone(ifname)

    def test_get_by_name(self):
        ifname, iface = loopback.get_by_name(self.cfg, "loop1")
        self.assertIsNotNone(iface)
        self.assertEqual("loop1", ifname)
        self.assertEqual(iface['mtu'], 2000)

        ifname, iface = loopback.get_by_name(self.cfg, "loop-noexist")
        self.assertIsNone(ifname)
        self.assertIsNone(iface)

    def test_enumerators(self):
        ifs = loopback.get_loopbacks(self.cfg)
        self.assertEqual(len(ifs), 3)
        self.assertIn("loop0", ifs)
        self.assertIn("loop1", ifs)
        self.assertIn("loop2", ifs)
        self.assertNotIn("loop-noexist", ifs)