import msgpack
from attic.testsuite import BaseTestCase
from attic.testsuite.mock import Mock
from attic.archive import Archive, CacheChunkBuffer, RobustUnpacker
from attic.key import PlaintextKey
from attic.helpers import Manifest
from datetime import datetime, timezone


class MockCache:

    def __init__(self):
        self.objects = {}

    def add_chunk(self, id, data, stats=None):
        self.objects[id] = data
        return id, len(data), len(data)


class ArchiveTimestampTestCase(BaseTestCase):

    def _test_timestamp_parsing(self, isoformat, expected):
        repository = Mock()
        key = PlaintextKey()
        manifest = Manifest(repository, key)
        a = Archive(repository, key, manifest, 'test', create=True)
        a.metadata = {b'time': isoformat}
        self.assert_equal(a.ts, expected)

    def test_with_microseconds(self):
        self._test_timestamp_parsing(
            '1970-01-01T00:00:01.000001',
            datetime(1970, 1, 1, 0, 0, 1, 1, timezone.utc))

    def test_without_microseconds(self):
        self._test_timestamp_parsing(
            '1970-01-01T00:00:01',
            datetime(1970, 1, 1, 0, 0, 1, 0, timezone.utc))


class ChunkBufferTestCase(BaseTestCase):

    def test(self):
        data = [{b'foo': 1}, {b'bar': 2}]
        cache = MockCache()
        key = PlaintextKey()
        chunks = CacheChunkBuffer(cache, key, None)
        for d in data:
            chunks.add(d)
            chunks.flush()
        chunks.flush(flush=True)
        self.assert_equal(len(chunks.chunks), 2)
        unpacker = msgpack.Unpacker()
        for id in chunks.chunks:
            unpacker.feed(cache.objects[id])
        self.assert_equal(data, list(unpacker))


class RobustUnpackerTestCase(BaseTestCase):

    def make_chunks(self, items):
        return b''.join(msgpack.packb({'path': item}) for item in items)

    def _validator(self, value):
        return isinstance(value, dict) and value.get(b'path') in (b'foo', b'bar', b'boo', b'baz')

    def process(self, input):
        unpacker = RobustUnpacker(validator=self._validator)
        result = []
        for should_sync, chunks in input:
            if should_sync:
                unpacker.resync()
            for data in chunks:
                unpacker.feed(data)
                for item in unpacker:
                    result.append(item)
        return result

    def test_extra_garbage_no_sync(self):
        chunks = [(False, [self.make_chunks([b'foo', b'bar'])]),
                  (False, [b'garbage'] + [self.make_chunks([b'boo', b'baz'])])]
        result = self.process(chunks)
        self.assert_equal(result, [
            {b'path': b'foo'}, {b'path': b'bar'},
            103, 97, 114, 98, 97, 103, 101,
            {b'path': b'boo'},
            {b'path': b'baz'}])

    def split(self, left, length):
        parts = []
        while left:
            parts.append(left[:length])
            left = left[length:]
        return parts

    def test_correct_stream(self):
        chunks = self.split(self.make_chunks([b'foo', b'bar', b'boo', b'baz']), 2)
        input = [(False, chunks)]
        result = self.process(input)
        self.assert_equal(result, [{b'path': b'foo'}, {b'path': b'bar'}, {b'path': b'boo'}, {b'path': b'baz'}])

    def test_missing_chunk(self):
        chunks = self.split(self.make_chunks([b'foo', b'bar', b'boo', b'baz']), 4)
        input = [(False, chunks[:3]), (True, chunks[4:])]
        result = self.process(input)
        self.assert_equal(result, [{b'path': b'foo'}, {b'path': b'boo'}, {b'path': b'baz'}])

    def test_corrupt_chunk(self):
        chunks = self.split(self.make_chunks([b'foo', b'bar', b'boo', b'baz']), 4)
        input = [(False, chunks[:3]), (True, [b'gar', b'bage'] + chunks[3:])]
        result = self.process(input)
        self.assert_equal(result, [{b'path': b'foo'}, {b'path': b'boo'}, {b'path': b'baz'}])