import io
import unittest
from munch import Munch

from minecraft.networking.modern import (
    ModernPlayingReactor, SetEntityDataPacket,
)
from mosfet.info import items
from mosfet.protocol.managers import EntityManager
from mosfet.world import World


def encode_varint(value):
    encoded = bytearray()
    while value & ~0x7F:
        encoded.append((value & 0x7F) | 0x80)
        value >>= 7
    encoded.append(value)
    return bytes(encoded)


class SaplingEntityTests(unittest.TestCase):
    def test_protocol_777_item_metadata_decodes_item_stack(self):
        sapling_id = items.get_id('oak_sapling')
        payload = (
            encode_varint(42) +
            bytes((8,)) + encode_varint(7) +
            encode_varint(1) + encode_varint(sapling_id) +
            encode_varint(0) + encode_varint(0) +
            bytes((0xFF,))
        )
        packet = SetEntityDataPacket()
        packet.read(io.BytesIO(payload))

        self.assertEqual(packet.entity_id, 42)
        self.assertEqual(len(packet.item_stacks), 1)
        self.assertEqual(packet.item_stacks[0].item_id, sapling_id)
        self.assertIn(SetEntityDataPacket,
                      ModernPlayingReactor.get_clientbound_packets(None))

    def test_item_metadata_makes_dropped_sapling_searchable(self):
        sapling_id = items.get_id('oak_sapling')
        entity = Munch(entity_id=42, x=1.0, y=65.0, z=2.0)
        manager = object.__new__(EntityManager)
        manager.g = Munch(objects={42: entity})
        packet = Munch(
            entity_id=42,
            item_stacks=[Munch(present=True, item_id=sapling_id,
                               item_count=1)],
        )
        manager.handle_entity_data(packet)

        found = World(Munch(objects={42: entity})).find_objects(
            items.SAPLING_IDS)
        self.assertEqual(found, [entity])
        self.assertEqual(entity.item_count, 1)


if __name__ == '__main__':
    unittest.main()