"""Tests for server discovery functionality."""

import pytest
from src.shared.discovery import (
    ServerInfo,
    DiscoveryMessage,
    create_multicast_socket,
    get_local_ip,
)


class TestServerInfo:
    """Test suite for ServerInfo class."""

    def test_server_info_creation(self) -> None:
        """Test creating ServerInfo."""
        info = ServerInfo(
            host="192.168.1.100",
            port=8888,
            server_name="Test Server",
            players_count=3,
        )

        assert info.host == "192.168.1.100"
        assert info.port == 8888
        assert info.server_name == "Test Server"
        assert info.players_count == 3

    def test_server_info_serialization(self) -> None:
        """Test ServerInfo to_dict and from_dict."""
        info = ServerInfo(
            host="10.0.0.1",
            port=9999,
            server_name="Game Room",
            players_count=2,
        )

        # Serialize
        data = info.to_dict()
        assert data["host"] == "10.0.0.1"
        assert data["port"] == 9999
        assert data["server_name"] == "Game Room"
        assert data["players_count"] == 2

        # Deserialize
        info2 = ServerInfo.from_dict(data)
        assert info2.host == info.host
        assert info2.port == info.port
        assert info2.server_name == info.server_name
        assert info2.players_count == info.players_count

    def test_server_info_host_override(self) -> None:
        """Test ServerInfo from_dict with host override."""
        data = {
            "host": "1.2.3.4",
            "port": 8888,
            "server_name": "Test",
            "players_count": 1,
        }

        # Override host
        info = ServerInfo.from_dict(data, host="5.6.7.8")
        assert info.host == "5.6.7.8"
        assert info.port == 8888


class TestDiscoveryMessage:
    """Test suite for DiscoveryMessage class."""

    def test_create_discover_message(self) -> None:
        """Test creating DISCOVER message."""
        msg = DiscoveryMessage.create_discover()
        assert isinstance(msg, bytes)

        # Parse it back
        msg_type, msg_data = DiscoveryMessage.parse(msg)
        assert msg_type == DiscoveryMessage.DISCOVER
        assert msg_data is None or msg_data == {}

    def test_create_announce_message(self) -> None:
        """Test creating SERVER_ANNOUNCE message."""
        server_info = ServerInfo(
            host="192.168.1.1",
            port=8888,
            server_name="Test Server",
            players_count=5,
        )

        msg = DiscoveryMessage.create_announce(server_info)
        assert isinstance(msg, bytes)

        # Parse it back
        msg_type, msg_data = DiscoveryMessage.parse(msg)
        assert msg_type == DiscoveryMessage.SERVER_ANNOUNCE
        assert msg_data is not None
        assert msg_data["host"] == "192.168.1.1"
        assert msg_data["port"] == 8888
        assert msg_data["server_name"] == "Test Server"
        assert msg_data["players_count"] == 5

    def test_parse_invalid_message(self) -> None:
        """Test parsing invalid message."""
        msg_type, msg_data = DiscoveryMessage.parse(b"invalid json")
        assert msg_type is None
        assert msg_data is None

    def test_message_round_trip(self) -> None:
        """Test encoding and decoding messages."""
        # Test DISCOVER
        discover = DiscoveryMessage.create_discover()
        msg_type, _ = DiscoveryMessage.parse(discover)
        assert msg_type == DiscoveryMessage.DISCOVER

        # Test ANNOUNCE
        info = ServerInfo(
            host="10.0.0.1",
            port=7777,
            server_name="Round Trip",
            players_count=0,
        )
        announce = DiscoveryMessage.create_announce(info)
        msg_type, msg_data = DiscoveryMessage.parse(announce)
        assert msg_type == DiscoveryMessage.SERVER_ANNOUNCE
        assert msg_data["server_name"] == "Round Trip"


class TestDiscoveryUtilities:
    """Test suite for discovery utility functions."""

    def test_create_multicast_socket(self) -> None:
        """Test creating multicast socket."""
        # Test without binding
        sock = create_multicast_socket(bind=False)
        assert sock is not None
        sock.close()

        # Test with binding (may fail in some environments)
        try:
            sock = create_multicast_socket(bind=True)
            assert sock is not None
            sock.close()
        except Exception:
            # Binding may fail in restricted environments
            pytest.skip("Cannot bind to multicast group in this environment")

    def test_get_local_ip(self) -> None:
        """Test getting local IP address."""
        ip = get_local_ip()
        assert isinstance(ip, str)
        assert len(ip) > 0

        # Should be a valid IP format
        parts = ip.split(".")
        assert len(parts) == 4

        # Each part should be a number 0-255
        for part in parts:
            num = int(part)
            assert 0 <= num <= 255