# test_sync_deferred.py
# Copyright (C) 2014 LEAP
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
"""
Test Leap backend bits: sync with deferred encryption.
"""
import time
import os
import random
import string
import shutil

from twisted.internet import defer

from leap.soledad.client import sync
from leap.soledad.client.sqlcipher import SQLCipherOptions
from leap.soledad.client.sqlcipher import SQLCipherDatabase

from testscenarios import TestWithScenarios

from test_soledad import u1db_tests as tests
from test_soledad.util import ADDRESS
from test_soledad.util import SoledadWithCouchServerMixin
from test_soledad.util import make_soledad_app
from test_soledad.util import soledad_sync_target


WAIT_STEP = 1
MAX_WAIT = 10
DBPASS = "pass"


class BaseSoledadDeferredEncTest(SoledadWithCouchServerMixin):

    """
    Another base class for testing the deferred encryption during
    the syncs, using the intermediate database.
    """
    defer_sync_encryption = True

    def setUp(self):
        SoledadWithCouchServerMixin.setUp(self)
        self.startTwistedServer()
        # config info
        self.db1_file = os.path.join(self.tempdir, "db1.u1db")
        os.unlink(self.db1_file)
        self.db_pass = DBPASS
        self.email = ADDRESS

        # get a random prefix for each test, so we do not mess with
        # concurrency during initialization and shutting down of
        # each local db.
        self.rand_prefix = ''.join(
            map(lambda x: random.choice(string.ascii_letters), range(6)))

        # open test dbs: db1 will be the local sqlcipher db (which
        # instantiates a syncdb). We use the self._soledad instance that was
        # already created on some setUp method.
        import binascii
        tohex = binascii.b2a_hex
        key = tohex(self._soledad.secrets.get_local_storage_key())
        dbpath = self._soledad._local_db_path

        self.opts = SQLCipherOptions(
            dbpath, key, is_raw_key=True, create=False)
        self.db1 = SQLCipherDatabase(self.opts)

        self.db2 = self.request_state._create_database('test')

    def tearDown(self):
        # XXX should not access "private" attrs
        shutil.rmtree(os.path.dirname(self._soledad._local_db_path))
        SoledadWithCouchServerMixin.tearDown(self)


class SyncTimeoutError(Exception):

    """
    Dummy exception to notify timeout during sync.
    """
    pass


class TestSoledadDbSyncDeferredEncDecr(
        TestWithScenarios,
        BaseSoledadDeferredEncTest,
        tests.TestCaseWithServer):

    """
    Test db.sync remote sync shortcut.
    Case with deferred encryption: using the intermediate
    syncdb.
    """

    scenarios = [
        ('http', {
            'make_app_with_state': make_soledad_app,
            'make_database_for_test': tests.make_memory_database_for_test,
        }),
    ]

    oauth = False
    token = True

    def setUp(self):
        """
        Need to explicitely invoke inicialization on all bases.
        """
        BaseSoledadDeferredEncTest.setUp(self)
        self.server = self.server_thread = None
        self.syncer = None

    def tearDown(self):
        """
        Need to explicitely invoke destruction on all bases.
        """
        dbsyncer = getattr(self, 'dbsyncer', None)
        if dbsyncer:
            dbsyncer.close()
        BaseSoledadDeferredEncTest.tearDown(self)

    def do_sync(self):
        """
        Perform sync using SoledadSynchronizer, SoledadSyncTarget
        and Token auth.
        """
        replica_uid = self._soledad._dbpool.replica_uid
        dbsyncer = self._soledad._dbsyncer  # Soledad.sync uses the dbsyncer

        target = soledad_sync_target(
            self, self.db2._dbname,
            source_replica_uid=replica_uid)
        return sync.SoledadSynchronizer(
            dbsyncer,
            target).sync()

    def wait_for_sync(self):
        """
        Wait for sync to finish.
        """
        wait = 0
        syncer = self.syncer
        if syncer is not None:
            while syncer.syncing:
                time.sleep(WAIT_STEP)
                wait += WAIT_STEP
                if wait >= MAX_WAIT:
                    raise SyncTimeoutError

    @defer.inlineCallbacks
    def test_db_sync(self):
        """
        Test sync.

        Adapted to check for encrypted content.
        """
        doc1 = self.db1.create_doc_from_json(tests.simple_doc)
        doc2 = self.db2.create_doc_from_json(tests.nested_doc)
        local_gen_before_sync = yield self.do_sync()

        gen, _, changes = self.db1.whats_changed(local_gen_before_sync)
        self.assertEqual(1, len(changes))

        self.assertEqual(doc2.doc_id, changes[0][0])
        self.assertEqual(1, gen - local_gen_before_sync)

        self.assertGetEncryptedDoc(
            self.db2, doc1.doc_id, doc1.rev, tests.simple_doc, False)
        self.assertGetEncryptedDoc(
            self.db1, doc2.doc_id, doc2.rev, tests.nested_doc, False)