# Copyright (C) 2011  Internet Systems Consortium.
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SYSTEMS CONSORTIUM
# DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
# INTERNET SYSTEMS CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
# FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
# NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
# WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

import isc.log
import unittest
from isc.datasrc import ZoneFinder
from isc.dns import Name, RRset, RRClass, RRType, RRTTL, Rdata
from isc.xfrin.diff import Diff, NoSuchZone

class TestError(Exception):
    """
    Just to have something to be raised during the tests.
    Not used outside.
    """
    pass

class DiffTest(unittest.TestCase):
    """
    Tests for the isc.xfrin.diff.Diff class.

    It also plays role of a data source and an updater, so it can manipulate
    some test variables while being called.
    """
    def setUp(self):
        """
        This sets internal variables so we can see nothing was called yet.

        It also creates some variables used in multiple tests.
        """
        # Track what was called already
        self.__updater_requested = False
        self.__compact_called = False
        self.__data_operations = []
        self.__apply_called = False
        self.__commit_called = False
        self.__broken_called = False
        self.__warn_called = False
        self.__should_replace = False
        self.__find_called = False
        self.__find_name = None
        self.__find_type = None
        self.__find_options = None
        self.__find_all_called = False
        self.__find_all_name = None
        self.__find_all_options = None
        # Some common values
        self.__rrclass = RRClass.IN()
        self.__type = RRType.A()
        self.__ttl = RRTTL(3600)
        # And RRsets
        # Create two valid rrsets
        self.__rrset1 = RRset(Name('a.example.org.'), self.__rrclass,
                              self.__type, self.__ttl)
        self.__rdata = Rdata(self.__type, self.__rrclass, '192.0.2.1')
        self.__rrset1.add_rdata(self.__rdata)
        self.__rrset2 = RRset(Name('b.example.org.'), self.__rrclass,
                              self.__type, self.__ttl)
        self.__rrset2.add_rdata(self.__rdata)
        # And two invalid
        self.__rrset_empty = RRset(Name('empty.example.org.'), self.__rrclass,
                                   self.__type, self.__ttl)
        self.__rrset_multi = RRset(Name('multi.example.org.'), self.__rrclass,
                                   self.__type, self.__ttl)
        self.__rrset_multi.add_rdata(self.__rdata)
        self.__rrset_multi.add_rdata(Rdata(self.__type, self.__rrclass,
                                           '192.0.2.2'))

        # Also create a few other (valid) rrsets
        # A SOA record
        self.__rrset_soa = RRset(Name('example.org.'), self.__rrclass,
                                 RRType.SOA(), RRTTL(3600))
        self.__rrset_soa.add_rdata(Rdata(RRType.SOA(), self.__rrclass,
                                         "ns1.example.org. " +
                                         "admin.example.org. " +
                                         "1233 3600 1800 2419200 7200"))
        # A few single-rr rrsets that together would for a multi-rr rrset
        self.__rrset3 = RRset(Name('c.example.org.'), self.__rrclass,
                              RRType.TXT(), self.__ttl)
        self.__rrset3.add_rdata(Rdata(RRType.TXT(), self.__rrclass, "one"))
        self.__rrset4 = RRset(Name('c.example.org.'), self.__rrclass,
                              RRType.TXT(), self.__ttl)
        self.__rrset4.add_rdata(Rdata(RRType.TXT(), self.__rrclass, "two"))
        self.__rrset5 = RRset(Name('c.example.org.'), self.__rrclass,
                              RRType.TXT(), self.__ttl)
        self.__rrset5.add_rdata(Rdata(RRType.TXT(), self.__rrclass, "three"))
        self.__rrset6 = RRset(Name('d.example.org.'), self.__rrclass,
                              RRType.A(), self.__ttl)
        self.__rrset6.add_rdata(Rdata(RRType.A(), self.__rrclass, "192.0.2.1"))
        self.__rrset7 = RRset(Name('d.example.org.'), self.__rrclass,
                              RRType.A(), self.__ttl)
        self.__rrset7.add_rdata(Rdata(RRType.A(), self.__rrclass, "192.0.2.2"))

    def __mock_compact(self):
        """
        This can be put into the diff to hook into its compact method and see
        if it gets called.
        """
        self.__compact_called = True

    def __mock_apply(self):
        """
        This can be put into the diff to hook into its apply method and see
        it gets called.
        """
        self.__apply_called = True

    def __broken_operation(self, *args):
        """
        This can be used whenever an operation should fail. It raises TestError.
        It should take whatever amount of parameters needed, so it can be put
        quite anywhere.
        """
        self.__broken_called = True
        raise TestError("Test error")

    def warn(self, *args):
        """
        This is for checking the warn function was called, we replace the logger
        in the tested module.
        """
        self.__warn_called = True
        # Also log the message so we can check the log format (manually)
        self.orig_logger.warn(*args)

    def commit(self):
        """
        This is part of pretending to be a zone updater. This notes the commit
        was called.
        """
        self.__commit_called = True

    def add_rrset(self, rrset):
        """
        This one is part of pretending to be a zone updater. It writes down
        addition of an rrset was requested.
        """
        self.__data_operations.append(('add', rrset))

    def delete_rrset(self, rrset):
        """
        This one is part of pretending to be a zone updater. It writes down
        removal of an rrset was requested.
        """
        self.__data_operations.append(('delete', rrset))

    def get_class(self):
        """
        This one is part of pretending to be a zone updater. It returns
        the IN class.
        """
        return self.__rrclass

    def get_updater(self, zone_name, replace, journaling=False):
        """
        This one pretends this is the data source client and serves
        getting an updater.

        If zone_name is 'none.example.org.', it returns None, otherwise
        it returns self.
        """
        # The diff should not delete the old data.
        self.assertEqual(self.__should_replace, replace)
        self.__updater_requested = True
        if zone_name == Name('none.example.org.'):
            # Pretend this zone doesn't exist
            return None

        # If journaling is enabled, record the fact; for a special zone
        # pretend that we don't support journaling.
        if journaling:
            if zone_name == Name('nodiff.example.org'):
                raise isc.datasrc.NotImplemented('journaling not supported')
            self.__journaling_enabled = True
        else:
            self.__journaling_enabled = False

        return self

    def find(self, name, rrtype, options=None):
        self.__find_called = True
        self.__find_name = name
        self.__find_type = rrtype
        self.__find_options = options
        # Doesn't really matter what is returned, as long
        # as the test can check that it's passed along
        return "find_return"

    def find_all(self, name, options=None):
        self.__find_all_called = True
        self.__find_all_name = name
        self.__find_all_options = options
        # Doesn't really matter what is returned, as long
        # as the test can check that it's passed along
        return "find_all_return"

    def test_create(self):
        """
        This test the case when the diff is successfuly created. It just
        tries it does not throw and gets the updater.
        """
        diff = Diff(self, Name('example.org.'))
        self.assertTrue(self.__updater_requested)
        self.assertEqual([], diff.get_buffer())
        # By default journaling is disabled
        self.assertFalse(self.__journaling_enabled)

    def test_create_nonexist(self):
        """
        Try to create a diff on a zone that doesn't exist. This should
        raise a correct exception.
        """
        self.assertRaises(NoSuchZone, Diff, self, Name('none.example.org.'))
        self.assertTrue(self.__updater_requested)

    def test_create_withjournal(self):
        Diff(self, Name('example.org'), False, True)
        self.assertTrue(self.__journaling_enabled)

    def test_create_nojournal(self):
        Diff(self, Name('nodiff.example.org'), False, True)
        self.assertFalse(self.__journaling_enabled)

    def __data_common(self, diff, method, operation):
        """
        Common part of test for test_add and test_delte.
        """
        # Try putting there the bad data first
        self.assertRaises(ValueError, method, self.__rrset_empty)
        self.assertRaises(ValueError, method, self.__rrset_multi)
        # They were not added
        self.assertEqual([], diff.get_buffer())
        # Put some proper data into the diff
        method(self.__rrset1)
        method(self.__rrset2)
        dlist = [(operation, self.__rrset1), (operation, self.__rrset2)]
        self.assertEqual(dlist, diff.get_buffer())
        # Check the data are not destroyed by raising an exception because of
        # bad data
        self.assertRaises(ValueError, method, self.__rrset_empty)
        self.assertEqual(dlist, diff.get_buffer())

    def test_add(self):
        """
        Try to add few items into the diff and see they are stored in there.

        Also try passing an rrset that has differnt amount of RRs than 1.
        """
        diff = Diff(self, Name('example.org.'))
        self.__data_common(diff, diff.add_data, 'add')

    def test_delete(self):
        """
        Try scheduling removal of few items into the diff and see they are
        stored in there.

        Also try passing an rrset that has different amount of RRs than 1.
        """
        diff = Diff(self, Name('example.org.'))
        self.__data_common(diff, diff.delete_data, 'delete')

    def test_apply(self):
        """
        Schedule few additions and check the apply works by passing the
        data into the updater.
        """
        # Prepare the diff
        diff = Diff(self, Name('example.org.'))
        diff.add_data(self.__rrset1)
        diff.delete_data(self.__rrset2)
        dlist = [('add', self.__rrset1), ('delete', self.__rrset2)]
        self.assertEqual(dlist, diff.get_buffer())
        # Do the apply, hook the compact method
        diff.compact = self.__mock_compact
        diff.apply()
        # It should call the compact
        self.assertTrue(self.__compact_called)
        # And pass the data. Our local history of what happened is the same
        # format, so we can check the same way
        self.assertEqual(dlist, self.__data_operations)
        # And the buffer in diff should become empty, as everything
        # got inside.
        self.assertEqual([], diff.get_buffer())

    def test_commit(self):
        """
        If we call a commit, it should first apply whatever changes are
        left (we hook into that instead of checking the effect) and then
        the commit on the updater should have been called.

        Then we check it raises value error for whatever operation we try.
        """
        diff = Diff(self, Name('example.org.'))
        diff.add_data(self.__rrset1)
        orig_apply = diff.apply
        diff.apply = self.__mock_apply
        diff.commit()
        self.assertTrue(self.__apply_called)
        self.assertTrue(self.__commit_called)
        # The data should be handled by apply which we replaced.
        self.assertEqual([], self.__data_operations)
        # Now check all range of other methods raise ValueError
        self.assertRaises(ValueError, diff.commit)
        self.assertRaises(ValueError, diff.add_data, self.__rrset2)
        self.assertRaises(ValueError, diff.delete_data, self.__rrset1)
        self.assertRaises(ValueError, diff.find, Name('foo.example.org.'),
                          RRType.A())
        self.assertRaises(ValueError, diff.find_all, Name('foo.example.org.'))
        diff.apply = orig_apply
        self.assertRaises(ValueError, diff.apply)
        # This one does not state it should raise, so check it doesn't
        # But it is NOP in this situation anyway
        diff.compact()

    def test_autoapply(self):
        """
        Test the apply is called all by itself after 100 tasks are added.
        """
        diff = Diff(self, Name('example.org.'))
        # A method to check the apply is called _after_ the 100th element
        # is added. We don't use it anywhere else, so we define it locally
        # as lambda function
        def check():
            self.assertEqual(100, len(diff.get_buffer()))
            self.__mock_apply()
        orig_apply = diff.apply
        diff.apply = check
        # If we put 99, nothing happens yet
        for i in range(0, 99):
            diff.add_data(self.__rrset1)
        expected = [('add', self.__rrset1)] * 99
        self.assertEqual(expected, diff.get_buffer())
        self.assertFalse(self.__apply_called)
        # Now we push the 100th and it should call the apply method
        # This will _not_ flush the data yet, as we replaced the method.
        # It, however, would in the real life.
        diff.add_data(self.__rrset1)
        # Now the apply method (which is replaced by our check) should
        # have been called. If it wasn't, this is false. If it was, but
        # still with 99 elements, the check would complain
        self.assertTrue(self.__apply_called)
        # Reset the buffer by calling the original apply.
        orig_apply()
        self.assertEqual([], diff.get_buffer())
        # Similar with delete
        self.__apply_called = False
        for i in range(0, 99):
            diff.delete_data(self.__rrset2)
        expected = [('delete', self.__rrset2)] * 99
        self.assertEqual(expected, diff.get_buffer())
        self.assertFalse(self.__apply_called)
        diff.delete_data(self.__rrset2)
        self.assertTrue(self.__apply_called)

    def test_compact(self):
        """
        Test the compaction works as expected, eg. it compacts only consecutive
        changes of the same operation and on the same domain/type.

        The test case checks that it does merge them, but also puts some
        different operations "in the middle", changes the type and name and
        places the same kind of change further away of each other to see they
        are not merged in that case.
        """
        diff = Diff(self, Name('example.org.'))
        # Check we can do a compact on empty data, it shouldn't break
        diff.compact()
        self.assertEqual([], diff.get_buffer())
        # This data is the way it should look like after the compact
        # ('operation', 'domain.prefix', 'type', ['rdata', 'rdata'])
        # The notes say why the each of consecutive can't be merged
        data = [
            ('add', 'a', 'A', ['192.0.2.1', '192.0.2.2']),
            # Different type.
            ('add', 'a', 'AAAA', ['2001:db8::1', '2001:db8::2']),
            # Different operation
            ('delete', 'a', 'AAAA', ['2001:db8::3']),
            # Different domain
            ('delete', 'b', 'AAAA', ['2001:db8::4']),
            # This does not get merged with the first, even if logically
            # possible. We just don't do this.
            ('add', 'a', 'A', ['192.0.2.3'])
            ]
        # Now, fill the data into the diff, in a "flat" way, one by one
        for (op, nprefix, rrtype, rdata) in data:
            name = Name(nprefix + '.example.org.')
            rrtype_obj = RRType(rrtype)
            for rdatum in rdata:
                rrset = RRset(name, self.__rrclass, rrtype_obj, self.__ttl)
                rrset.add_rdata(Rdata(rrtype_obj, self.__rrclass, rdatum))
                if op == 'add':
                    diff.add_data(rrset)
                else:
                    diff.delete_data(rrset)
        # Compact it
        diff.compact()
        # Now check they got compacted. They should be in the same order as
        # pushed inside. So it should be the same as data modulo being in
        # the rrsets and isc.dns objects.
        def check():
            buf = diff.get_buffer()
            self.assertEqual(len(data), len(buf))
            for (expected, received) in zip(data, buf):
                (eop, ename, etype, edata) = expected
                (rop, rrrset) = received
                self.assertEqual(eop, rop)
                ename_obj = Name(ename + '.example.org.')
                self.assertEqual(ename_obj, rrrset.get_name())
                # We check on names to make sure they are printed nicely
                self.assertEqual(etype, str(rrrset.get_type()))
                rdata = rrrset.get_rdata()
                self.assertEqual(len(edata), len(rdata))
                # It should also preserve the order
                for (edatum, rdatum) in zip(edata, rdata):
                    self.assertEqual(edatum, str(rdatum))
        check()
        # Try another compact does nothing, but survives
        diff.compact()
        check()

    def test_wrong_class(self):
        """
        Test a wrong class of rrset is rejected.
        """
        diff = Diff(self, Name('example.org.'))
        rrset = RRset(Name('a.example.org.'), RRClass.CH(), RRType.NS(),
                      self.__ttl)
        rrset.add_rdata(Rdata(RRType.NS(), RRClass.CH(), 'ns.example.org.'))
        self.assertRaises(ValueError, diff.add_data, rrset)
        self.assertRaises(ValueError, diff.delete_data, rrset)

    def __do_raise_test(self):
        """
        Do a raise test. Expects that one of the operations is exchanged for
        broken version.
        """
        diff = Diff(self, Name('example.org.'))
        diff.add_data(self.__rrset1)
        diff.delete_data(self.__rrset2)
        self.assertRaises(TestError, diff.commit)
        self.assertTrue(self.__broken_called)
        self.assertRaises(ValueError, diff.add_data, self.__rrset1)
        self.assertRaises(ValueError, diff.delete_data, self.__rrset2)
        self.assertRaises(ValueError, diff.commit)
        self.assertRaises(ValueError, diff.apply)

    def test_raise_add(self):
        """
        Test the exception from add_rrset is propagated and the diff can't be
        used afterwards.
        """
        self.add_rrset = self.__broken_operation
        self.__do_raise_test()

    def test_raise_delete(self):
        """
        Test the exception from delete_rrset is propagated and the diff can't be
        used afterwards.
        """
        self.delete_rrset = self.__broken_operation
        self.__do_raise_test()

    def test_raise_commit(self):
        """
        Test the exception from updater's commit gets propagated and it can't be
        used afterwards.
        """
        self.commit = self.__broken_operation
        self.__do_raise_test()

    def test_ttl(self):
        """
        Test the TTL handling. A warn function should have been called if they
        differ, but that's all, it should not crash or raise.
        """
        self.orig_logger = isc.xfrin.diff.logger
        try:
            isc.xfrin.diff.logger = self
            diff = Diff(self, Name('example.org.'))
            diff.add_data(self.__rrset1)
            rrset2 = RRset(Name('a.example.org.'), self.__rrclass,
                                  self.__type, RRTTL(120))
            rrset2.add_rdata(Rdata(self.__type, self.__rrclass, '192.10.2.2'))
            diff.add_data(rrset2)
            rrset2 = RRset(Name('a.example.org.'), self.__rrclass,
                                  self.__type, RRTTL(6000))
            rrset2.add_rdata(Rdata(self.__type, self.__rrclass, '192.10.2.3'))
            diff.add_data(rrset2)
            # They should get compacted together and complain.
            diff.compact()
            self.assertEqual(1, len(diff.get_buffer()))
            # The TTL stays on the first value, no matter if smaller or bigger
            # ones come later.
            self.assertEqual(self.__ttl, diff.get_buffer()[0][1].get_ttl())
            self.assertTrue(self.__warn_called)
        finally:
            isc.xfrin.diff.logger = self.orig_logger

    def test_rrsig_ttl(self):
        '''Similar to the previous test, but for RRSIGs of different covered
        types.

        They shouldn't be compacted.

        '''
        diff = Diff(self, Name('example.org.'))
        rrsig1 = RRset(Name('example.org'), self.__rrclass,
                       RRType.RRSIG(), RRTTL(3600))
        rrsig1.add_rdata(Rdata(RRType.RRSIG(), self.__rrclass,
                               'A 5 3 3600 20000101000000 20000201000000 ' +
                               '0 example.org. FAKEFAKEFAKE'))
        diff.add_data(rrsig1)
        rrsig2 = RRset(Name('example.org'), self.__rrclass,
                       RRType.RRSIG(), RRTTL(1800))
        rrsig2.add_rdata(Rdata(RRType.RRSIG(), self.__rrclass,
                               'AAAA 5 3 3600 20000101000000 20000201000000 ' +
                               '1 example.org. FAKEFAKEFAKE'))
        diff.add_data(rrsig2)
        diff.compact()
        self.assertEqual(2, len(diff.get_buffer()))

    def test_replace(self):
        '''
        Test that when we want to replace the whole zone, it is propagated.
        '''
        self.__should_replace = True
        diff = Diff(self, "example.org.", True)
        self.assertTrue(self.__updater_requested)

    def test_get_buffer(self):
        '''
        Test that the getters raise when used in the wrong mode
        '''
        diff_multi = Diff(self, Name('example.org.'), single_update_mode=False)
        self.assertRaises(ValueError, diff_multi.get_single_update_buffers)
        self.assertEqual([], diff_multi.get_buffer())

        diff_single = Diff(self, Name('example.org.'), single_update_mode=True)
        self.assertRaises(ValueError, diff_single.get_buffer)
        self.assertEqual(([], []), diff_single.get_single_update_buffers())

    def test_finds_single(self):
        '''
        Test that find_updated() and find_all_updated() can only be used
        in single-update-mode.
        '''
        diff_multi = Diff(self, Name('example.org.'), single_update_mode=False)
        self.assertRaises(ValueError, diff_multi.find_updated,
                          Name('example.org.'), RRType.A())
        self.assertRaises(ValueError, diff_multi.find_all_updated,
                          Name('example.org.'))

    def test_single_update_mode(self):
        '''
        Test single-update mode. In this mode, updates and deletes can
        be done in any order, but there may only be one changeset.
        For both updates and deletes, exactly one SOA rr must be given,
        and it must be the first change.
        '''

        # full rrset for A (to check compact())
        txt = RRset(Name('c.example.org.'), self.__rrclass, RRType.TXT(),
                    RRTTL(3600))
        txt.add_rdata(Rdata(txt.get_type(), txt.get_class(), "one"))
        txt.add_rdata(Rdata(txt.get_type(), txt.get_class(), "two"))
        txt.add_rdata(Rdata(txt.get_type(), txt.get_class(), "three"))
        a = RRset(Name('d.example.org.'), self.__rrclass, RRType.A(),
                  RRTTL(3600))
        a.add_rdata(Rdata(a.get_type(), a.get_class(), "192.0.2.1"))
        a.add_rdata(Rdata(a.get_type(), a.get_class(), "192.0.2.2"))

        diff = Diff(self, Name('example.org.'), single_update_mode=True)

        # adding a first should fail
        self.assertRaises(ValueError, diff.add_data, a)
        # But soa should work
        diff.add_data(self.__rrset_soa)
        # And then A should as well
        diff.add_data(self.__rrset3)
        diff.add_data(self.__rrset4)
        diff.add_data(self.__rrset5)
        # But another SOA should fail again
        self.assertRaises(ValueError, diff.add_data, self.__rrset_soa)

        # Same for delete
        self.assertRaises(ValueError, diff.delete_data, self.__rrset6)
        diff.delete_data(self.__rrset_soa)
        diff.delete_data(self.__rrset6)
        diff.delete_data(self.__rrset7)
        self.assertRaises(ValueError, diff.delete_data, self.__rrset_soa)

        # Not compacted yet, so the buffers should be as we
        # filled them
        (delbuf, addbuf) = diff.get_single_update_buffers()
        self.assertEqual([('delete', self.__rrset_soa),
                          ('delete', self.__rrset6),
                          ('delete', self.__rrset7)], delbuf)
        self.assertEqual([('add', self.__rrset_soa),
                          ('add', self.__rrset3),
                          ('add', self.__rrset4),
                          ('add', self.__rrset5)], addbuf)

        # Compact should compact the A records in both buffers
        diff.compact()
        (delbuf, addbuf) = diff.get_single_update_buffers()
        # need rrset equality again :/
        self.assertEqual(2, len(delbuf))
        self.assertEqual(2, len(delbuf[0]))
        self.assertEqual('delete', delbuf[0][0])
        self.assertEqual(self.__rrset_soa.to_text(), delbuf[0][1].to_text())
        self.assertEqual(2, len(delbuf[1]))
        self.assertEqual('delete', delbuf[1][0])
        self.assertEqual(a.to_text(), delbuf[1][1].to_text())

        self.assertEqual(2, len(addbuf))
        self.assertEqual(2, len(addbuf[0]))
        self.assertEqual('add', addbuf[0][0])
        self.assertEqual(self.__rrset_soa.to_text(), addbuf[0][1].to_text())
        self.assertEqual(2, len(addbuf[1]))
        self.assertEqual('add', addbuf[1][0])
        self.assertEqual(txt.to_text(), addbuf[1][1].to_text())

        # Apply should reset the buffers
        diff.apply()
        (delbuf, addbuf) = diff.get_single_update_buffers()
        self.assertEqual([], delbuf)
        self.assertEqual([], addbuf)

        # Now the change has been applied, and the buffers are cleared,
        # Adding non-SOA records should fail again.
        self.assertRaises(ValueError, diff.add_data, a)
        self.assertRaises(ValueError, diff.delete_data, a)

    def test_add_delete_same(self):
        '''
        Test that if a record is added, then deleted, it is not added to
        both buffers, but remove from the addition, and vice versa
        '''
        diff = Diff(self, Name('example.org.'), single_update_mode=True)
        # Need SOA records first
        diff.delete_data(self.__rrset_soa)
        diff.add_data(self.__rrset_soa)

        deletions, additions = diff.get_single_update_buffers()
        self.assertEqual(1, len(deletions))
        self.assertEqual(1, len(additions))

        diff.add_data(self.__rrset1)
        deletions, additions = diff.get_single_update_buffers()
        self.assertEqual(1, len(deletions))
        self.assertEqual(2, len(additions))

        diff.delete_data(self.__rrset1)
        deletions, additions = diff.get_single_update_buffers()
        self.assertEqual(1, len(deletions))
        self.assertEqual(1, len(additions))

        diff.delete_data(self.__rrset2)
        deletions, additions = diff.get_single_update_buffers()
        self.assertEqual(2, len(deletions))
        self.assertEqual(1, len(additions))

        diff.add_data(self.__rrset2)
        deletions, additions = diff.get_single_update_buffers()
        self.assertEqual(1, len(deletions))
        self.assertEqual(1, len(additions))

    def test_find(self):
        diff = Diff(self, Name('example.org.'))
        name = Name('www.example.org.')
        rrtype = RRType.A()

        self.assertFalse(self.__find_called)
        self.assertEqual(None, self.__find_name)
        self.assertEqual(None, self.__find_type)
        self.assertEqual(None, self.__find_options)

        self.assertEqual("find_return", diff.find(name, rrtype))

        self.assertTrue(self.__find_called)
        self.assertEqual(name, self.__find_name)
        self.assertEqual(rrtype, self.__find_type)
        self.assertEqual(ZoneFinder.NO_WILDCARD | ZoneFinder.FIND_GLUE_OK,
                         self.__find_options)

    def test_find_options(self):
        diff = Diff(self, Name('example.org.'))
        name = Name('foo.example.org.')
        rrtype = RRType.TXT()
        options = ZoneFinder.NO_WILDCARD

        self.assertEqual("find_return", diff.find(name, rrtype, options))

        self.assertTrue(self.__find_called)
        self.assertEqual(name, self.__find_name)
        self.assertEqual(rrtype, self.__find_type)
        self.assertEqual(options, self.__find_options)

    def test_find_all(self):
        diff = Diff(self, Name('example.org.'))
        name = Name('www.example.org.')

        self.assertFalse(self.__find_all_called)
        self.assertEqual(None, self.__find_all_name)
        self.assertEqual(None, self.__find_all_options)

        self.assertEqual("find_all_return", diff.find_all(name))

        self.assertTrue(self.__find_all_called)
        self.assertEqual(name, self.__find_all_name)
        self.assertEqual(ZoneFinder.NO_WILDCARD | ZoneFinder.FIND_GLUE_OK,
                         self.__find_all_options)

    def test_find_all_options(self):
        diff = Diff(self, Name('example.org.'))
        name = Name('www.example.org.')
        options = isc.datasrc.ZoneFinder.NO_WILDCARD

        self.assertFalse(self.__find_all_called)
        self.assertEqual(None, self.__find_all_name)
        self.assertEqual(None, self.__find_all_options)

        self.assertEqual("find_all_return", diff.find_all(name, options))

        self.assertTrue(self.__find_all_called)
        self.assertEqual(name, self.__find_all_name)
        self.assertEqual(options, self.__find_all_options)

    def __common_remove_rr_from_buffer(self, diff, add_method, remove_method,
                                       op_str, buf_nr):
        add_method(self.__rrset_soa)
        add_method(self.__rrset2)
        add_method(self.__rrset3)
        add_method(self.__rrset4)

        # sanity check
        buf = diff.get_single_update_buffers()[buf_nr]
        expected = [ (op_str, str(rr)) for rr in [ self.__rrset_soa,
                                                   self.__rrset2,
                                                   self.__rrset3,
                                                   self.__rrset4 ] ]
        result = [ (op, str(rr)) for (op, rr) in buf ]
        self.assertEqual(expected, result)

        # remove one
        self.assertTrue(remove_method(self.__rrset2))
        buf = diff.get_single_update_buffers()[buf_nr]
        expected = [ (op_str, str(rr)) for rr in [ self.__rrset_soa,
                                                   self.__rrset3,
                                                   self.__rrset4 ] ]
        result = [ (op, str(rr)) for (op, rr) in buf ]
        self.assertEqual(expected, result)

        # SOA should not be removed
        self.assertFalse(remove_method(self.__rrset_soa))
        buf = diff.get_single_update_buffers()[buf_nr]
        expected = [ (op_str, str(rr)) for rr in [ self.__rrset_soa,
                                                   self.__rrset3,
                                                   self.__rrset4 ] ]
        result = [ (op, str(rr)) for (op, rr) in buf ]
        self.assertEqual(expected, result)

        # remove another
        self.assertTrue(remove_method(self.__rrset4))
        buf = diff.get_single_update_buffers()[buf_nr]
        expected = [ (op_str, str(rr)) for rr in [ self.__rrset_soa,
                                                   self.__rrset3 ] ]
        result = [ (op, str(rr)) for (op, rr) in buf ]
        self.assertEqual(expected, result)

        # remove nonexistent should return False
        self.assertFalse(remove_method(self.__rrset4))
        buf = diff.get_single_update_buffers()[buf_nr]
        expected = [ (op_str, str(rr)) for rr in [ self.__rrset_soa,
                                                   self.__rrset3 ] ]
        result = [ (op, str(rr)) for (op, rr) in buf ]
        self.assertEqual(expected, result)

    def test_remove_rr_from_additions(self):
        diff = Diff(self, Name('example.org'), single_update_mode=True)
        self.__common_remove_rr_from_buffer(diff, diff.add_data,
                                               diff._remove_rr_from_additions,
                                               'add', 1)

    def test_remove_rr_from_deletions(self):
        diff = Diff(self, Name('example.org'), single_update_mode=True)
        self.__common_remove_rr_from_buffer(diff, diff.delete_data,
                                            diff._remove_rr_from_deletions,
                                            'delete', 0)

    def __create_find(self, result, rrset, flags):
        '''
        Overwrites the local find() method with a method that returns
        the tuple (result, rrset, flags)
        '''
        def new_find(name, rrtype, fflags):
            return (result, rrset, flags)
        self.find = new_find

    def __create_find_all(self, result, rrsets, flags):
        '''
        Overwrites the local find() method with a method that returns
        the tuple (result, rrsets, flags)
        '''
        def new_find_all(name, fflags):
            return (result, rrsets, flags)
        self.find_all = new_find_all

    def __check_find_call(self, method, query_rrset, expected_rcode,
                          expected_rdatas=None):
        '''
        Helper for find tests; calls the given method with the name and
        type of the given rrset. Checks for the given rcode.
        If expected_rdatas is not none, the result name, and type are
        checked to match the given rrset ones, and the rdatas are checked
        to be equal.
        The given method must have the same arguments and return type
        as find()
        '''
        result, rrset, _ = method(query_rrset.get_name(),
                                  query_rrset.get_type())
        self.assertEqual(expected_rcode, result)
        if expected_rdatas is not None:
            self.assertEqual(query_rrset.get_name(), rrset.get_name())
            self.assertEqual(query_rrset.get_type(), rrset.get_type())
            if expected_rdatas is not None:
                self.assertEqual(expected_rdatas, rrset.get_rdata())
        else:
            self.assertEqual(None, rrset)

    def __check_find_all_call(self, method, query_rrset, expected_rcode,
                              expected_rrs=[]):
        '''
        Helper for find tests; calls the given method with the name and
        type of the given rrset. Checks for the given rcode.
        If expected_rdatas is not none, the result name, and type are
        checked to match the given rrset ones, and the rdatas are checked
        to be equal.
        The given method must have the same arguments and return type
        as find()
        '''
        result, rrsets, _ = method(query_rrset.get_name())
        self.assertEqual(expected_rcode, result)
        # We have no real equality function for rrsets, but since
        # the rrsets in question are themselves returns, pointer equality
        # works as well
        self.assertEqual(expected_rrs, rrsets)

    def test_find_updated_existing_data(self):
        '''
        Tests whether existent data is updated with the additions and
        deletions from the Diff
        '''
        diff = Diff(self, Name('example.org'), single_update_mode=True)
        diff.add_data(self.__rrset_soa)
        diff.delete_data(self.__rrset_soa)

        # override the actual find method
        self.__create_find(ZoneFinder.SUCCESS, self.__rrset3, 0)

        # sanity check
        self.__check_find_call(diff.find_updated, self.__rrset3,
                               ZoneFinder.SUCCESS, self.__rrset3.get_rdata())

        # check that normal find also returns the original data
        self.__check_find_call(diff.find, self.__rrset3,
                               ZoneFinder.SUCCESS, self.__rrset3.get_rdata())

        # Adding another should have it returned in the find_updated
        diff.add_data(self.__rrset4)
        self.__check_find_call(diff.find_updated, self.__rrset3,
                               ZoneFinder.SUCCESS, self.__rrset3.get_rdata() +
                               self.__rrset4.get_rdata())

        # check that normal find still returns the original data
        self.__check_find_call(diff.find, self.__rrset3,
                               ZoneFinder.SUCCESS, self.__rrset3.get_rdata())

        # Adding a different type should have no effect
        diff.add_data(self.__rrset2)
        self.__check_find_call(diff.find_updated, self.__rrset3,
                               ZoneFinder.SUCCESS, self.__rrset3.get_rdata() +
                               self.__rrset4.get_rdata())

        # check that normal find still returns the original data
        self.__check_find_call(diff.find, self.__rrset3,
                               ZoneFinder.SUCCESS, self.__rrset3.get_rdata())

        # Deleting 3 now should result in only 4 being updated
        diff.delete_data(self.__rrset3)
        self.__check_find_call(diff.find_updated, self.__rrset3,
                               ZoneFinder.SUCCESS, self.__rrset4.get_rdata())

        # check that normal find still returns the original data
        self.__check_find_call(diff.find, self.__rrset3,
                               ZoneFinder.SUCCESS, self.__rrset3.get_rdata())

        # Deleting 4 now should result in empty rrset
        diff.delete_data(self.__rrset4)
        self.__check_find_call(diff.find_updated, self.__rrset3,
                               ZoneFinder.NXRRSET)

        # check that normal find still returns the original data
        self.__check_find_call(diff.find, self.__rrset3,
                               ZoneFinder.SUCCESS, self.__rrset3.get_rdata())

    def test_find_updated_nonexistent_data(self):
        '''
        Test whether added data for a query that would originally result
        in NXDOMAIN works
        '''
        diff = Diff(self, Name('example.org'), single_update_mode=True)
        diff.add_data(self.__rrset_soa)
        diff.delete_data(self.__rrset_soa)

        # override the actual find method
        self.__create_find(ZoneFinder.NXDOMAIN, None, 0)

        # Sanity check
        self.__check_find_call(diff.find_updated, self.__rrset3,
                               ZoneFinder.NXDOMAIN)
        self.__check_find_call(diff.find, self.__rrset3,
                               ZoneFinder.NXDOMAIN)

        # Add data and see it is returned
        diff.add_data(self.__rrset3)
        self.__check_find_call(diff.find_updated, self.__rrset3,
                               ZoneFinder.SUCCESS, self.__rrset3.get_rdata())
        self.__check_find_call(diff.find, self.__rrset3,
                               ZoneFinder.NXDOMAIN)

        # Add unrelated data, result should be the same
        diff.add_data(self.__rrset2)
        self.__check_find_call(diff.find_updated, self.__rrset3,
                               ZoneFinder.SUCCESS, self.__rrset3.get_rdata())
        self.__check_find_call(diff.find, self.__rrset3,
                               ZoneFinder.NXDOMAIN)

        # Remove, result should now be NXDOMAIN again
        diff.delete_data(self.__rrset3)
        result, rrset, _ = diff.find_updated(self.__rrset3.get_name(),
                                             self.__rrset3.get_type())
        self.__check_find_call(diff.find_updated, self.__rrset3,
                               ZoneFinder.NXDOMAIN)
        self.__check_find_call(diff.find, self.__rrset3,
                               ZoneFinder.NXDOMAIN)

    def test_find_updated_other(self):
        '''
        Test that any other ZoneFinder.result code is directly
        passed on.
        '''
        diff = Diff(self, Name('example.org'), single_update_mode=True)

        # Add and delete some data to make sure it's not used
        diff.add_data(self.__rrset_soa)
        diff.add_data(self.__rrset3)
        diff.delete_data(self.__rrset_soa)
        diff.delete_data(self.__rrset2)

        for rcode in [ ZoneFinder.DELEGATION,
                       ZoneFinder.CNAME,
                       ZoneFinder.DNAME ]:
            # override the actual find method
            self.__create_find(rcode, None, 0)
            self.__check_find_call(diff.find, self.__rrset3, rcode)
            self.__check_find_call(diff.find_updated, self.__rrset3, rcode)

    def test_find_all_existing_data(self):
        diff = Diff(self, Name('example.org'), single_update_mode=True)
        diff.add_data(self.__rrset_soa)
        diff.delete_data(self.__rrset_soa)

        # override the actual find method
        self.__create_find_all(ZoneFinder.SUCCESS, [ self.__rrset3 ], 0)

        # Sanity check
        result, rrsets, _ = diff.find_all_updated(self.__rrset3.get_name())
        self.assertEqual(ZoneFinder.SUCCESS, result)
        self.assertEqual([self.__rrset3], rrsets)

        self.__check_find_all_call(diff.find_all_updated, self.__rrset3,
                                   ZoneFinder.SUCCESS, [self.__rrset3])
        self.__check_find_all_call(diff.find_all, self.__rrset3,
                                   ZoneFinder.SUCCESS, [self.__rrset3])

        # Add a second rr with different type at same name
        add_rrset = RRset(self.__rrset3.get_name(), self.__rrclass,
                          RRType.A(), self.__ttl)
        add_rrset.add_rdata(Rdata(RRType.A(), self.__rrclass, "192.0.2.2"))
        diff.add_data(add_rrset)

        self.__check_find_all_call(diff.find_all_updated, self.__rrset3,
                                   ZoneFinder.SUCCESS,
                                   [self.__rrset3, add_rrset])
        self.__check_find_all_call(diff.find_all, self.__rrset3,
                                   ZoneFinder.SUCCESS, [self.__rrset3])

        # Remove original one
        diff.delete_data(self.__rrset3)
        self.__check_find_all_call(diff.find_all_updated, self.__rrset3,
                                   ZoneFinder.SUCCESS, [add_rrset])
        self.__check_find_all_call(diff.find_all, self.__rrset3,
                                   ZoneFinder.SUCCESS, [self.__rrset3])

        # And remove new one, result should then become NXDOMAIN
        diff.delete_data(add_rrset)
        result, rrsets, _ = diff.find_all_updated(self.__rrset3.get_name())

        self.assertEqual(ZoneFinder.NXDOMAIN, result)
        self.assertEqual([ ], rrsets)
        self.__check_find_all_call(diff.find_all_updated, self.__rrset3,
                                   ZoneFinder.NXDOMAIN)
        self.__check_find_all_call(diff.find_all, self.__rrset3,
                                   ZoneFinder.SUCCESS, [self.__rrset3])

    def test_find_all_nonexistent_data(self):
        diff = Diff(self, Name('example.org'), single_update_mode=True)
        diff.add_data(self.__rrset_soa)
        diff.delete_data(self.__rrset_soa)

        self.__create_find_all(ZoneFinder.NXDOMAIN, [], 0)

        # Sanity check
        self.__check_find_all_call(diff.find_all_updated, self.__rrset2,
                                   ZoneFinder.NXDOMAIN)
        self.__check_find_all_call(diff.find_all, self.__rrset2,
                                   ZoneFinder.NXDOMAIN)

        # Adding data should change the result
        diff.add_data(self.__rrset2)
        self.__check_find_all_call(diff.find_all_updated, self.__rrset2,
                                   ZoneFinder.SUCCESS, [ self.__rrset2 ])
        self.__check_find_all_call(diff.find_all, self.__rrset2,
                                   ZoneFinder.NXDOMAIN)

        # Adding data at other name should not
        diff.add_data(self.__rrset3)
        self.__check_find_all_call(diff.find_all_updated, self.__rrset2,
                                   ZoneFinder.SUCCESS, [ self.__rrset2 ])
        self.__check_find_all_call(diff.find_all, self.__rrset2,
                                   ZoneFinder.NXDOMAIN)

        # Deleting it should revert to original
        diff.delete_data(self.__rrset2)
        self.__check_find_all_call(diff.find_all_updated, self.__rrset2,
                                   ZoneFinder.NXDOMAIN)
        self.__check_find_all_call(diff.find_all, self.__rrset2,
                                   ZoneFinder.NXDOMAIN)

    def test_find_all_other_results(self):
        '''
        Any result code other than SUCCESS and NXDOMAIN should cause
        the results to be passed on directly
        '''
        diff = Diff(self, Name('example.org'), single_update_mode=True)

        # Add and delete some data to make sure it's not used
        diff.add_data(self.__rrset_soa)
        diff.add_data(self.__rrset3)
        diff.delete_data(self.__rrset_soa)
        diff.delete_data(self.__rrset2)

        for rcode in [ ZoneFinder.NXRRSET,
                       ZoneFinder.DELEGATION,
                       ZoneFinder.CNAME,
                       ZoneFinder.DNAME ]:
            # override the actual find method
            self.__create_find_all(rcode, [], 0)
            self.__check_find_all_call(diff.find_all_updated, self.__rrset2,
                                       rcode)
            self.__check_find_all_call(diff.find_all_updated, self.__rrset3,
                                       rcode)
            self.__check_find_all_call(diff.find_all, self.__rrset2,
                                       rcode)
            self.__check_find_all_call(diff.find_all, self.__rrset3,
                                       rcode)

if __name__ == "__main__":
    isc.log.init("bind10")
    isc.log.resetUnitTestRootLogger()
    unittest.main()
