import re
import unittest
from zope.component import queryUtility
from zope.interface.verify import verifyClass, verifyObject
from waeup.ikoba.testing import FunctionalLayer, FunctionalTestCase
from waeup.ikoba.utils.idgen import IIDSource, IDSource


# format of raw uuids (36 chars including 4 hyphens)
RE_FORMAT_UUID = re.compile(
    "^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$"
    )

# format of hex uuids (32 chars)
RE_FORMAT_HEX_UUID = re.compile("^[0-9a-f]{32}$")


class IDGeneratorTests(unittest.TestCase):

    def test_iface(self):
        # we fullfill any interface contracts
        src = IDSource()
        verifyClass(IIDSource, IDSource)
        verifyObject(IIDSource, src)

    def test_get_uuid(self):
        # we can get universally unique identifiers
        src = IDSource()
        result = src.get_uuid()
        assert(RE_FORMAT_UUID.match(result))
        assert src.get_uuid() != result

    def test_get_hex_uuid(self):
        # we can get UUIDs as hex strings
        src = IDSource()
        result = src.get_hex_uuid()
        assert (RE_FORMAT_HEX_UUID.match(result))
        assert src.get_hex_uuid() != result


class FunctionalIDSourceTests(FunctionalTestCase):

    layer = FunctionalLayer

    def test_IIDSource_utility_registered(self):
        # an IIDSource is registered on startup
        util = queryUtility(IIDSource)
        assert util is not None