"""Tests for bencode — TDD: tests before implementation."""

import pytest
from i2p_apps.snark.bencode import bencode, bdecode


class TestBencode:
    def test_encode_int(self):
        assert bencode(42) == b"i42e"

    def test_encode_negative_int(self):
        assert bencode(-1) == b"i-1e"

    def test_encode_zero(self):
        assert bencode(0) == b"i0e"

    def test_encode_string(self):
        assert bencode(b"spam") == b"4:spam"

    def test_encode_empty_string(self):
        assert bencode(b"") == b"0:"

    def test_encode_list(self):
        assert bencode([b"spam", b"eggs"]) == b"l4:spam4:eggse"

    def test_encode_dict(self):
        assert bencode({b"cow": b"moo", b"spam": b"eggs"}) == b"d3:cow3:moo4:spam4:eggse"

    def test_encode_nested(self):
        assert bencode({b"list": [1, 2, 3]}) == b"d4:listli1ei2ei3eee"


class TestBdecode:
    def test_decode_int(self):
        assert bdecode(b"i42e") == 42

    def test_decode_negative_int(self):
        assert bdecode(b"i-1e") == -1

    def test_decode_string(self):
        assert bdecode(b"4:spam") == b"spam"

    def test_decode_empty_string(self):
        assert bdecode(b"0:") == b""

    def test_decode_list(self):
        assert bdecode(b"l4:spam4:eggse") == [b"spam", b"eggs"]

    def test_decode_dict(self):
        result = bdecode(b"d3:cow3:moo4:spam4:eggse")
        assert result == {b"cow": b"moo", b"spam": b"eggs"}

    def test_decode_nested(self):
        result = bdecode(b"d4:listli1ei2ei3eee")
        assert result == {b"list": [1, 2, 3]}

    def test_roundtrip(self):
        original = {b"announce": b"http://tracker.i2p/announce", b"info": {b"name": b"test", b"length": 1024}}
        assert bdecode(bencode(original)) == original