from __future__ import annotations

import socket
import time

import pytest

from client_session import ClientSession
from packet_codec import EncodedPacket
from transport_policy import Delivery
from transport_server import TransportAwareFalloutTogetherServer


class MessageConnection:
    def __init__(self):
        self.messages: list[EncodedPacket] = []

    def send_encoded(self, encoded: EncodedPacket) -> None:
        self.messages.append(encoded)

    def fileno(self) -> int:
        return 1

    def close(self) -> None:
        pass


def make_client(connection) -> ClientSession:
    return ClientSession(
        connection=connection,
        address=("127.0.0.1", 50000),
        player_id=1,
        connected_at=time.time(),
    )


def test_transport_aware_server_preserves_tcp_wire_format():
    server = TransportAwareFalloutTogetherServer(host="127.0.0.1", port=0)
    reader, writer = socket.socketpair()
    try:
        client = make_client(writer)
        server._send_packet(client, {"type": "playerState", "characterName": "Nomad"})
        assert reader.recv(4096) == b'{"type":"playerState","characterName":"Nomad"}\n'
        assert client.packets_sent == 1
        assert server.get_stats()["packetsSent"] == 1
    finally:
        reader.close()
        writer.close()


def test_transport_aware_server_sends_raw_message_and_delivery_metadata_to_gns_style_connection():
    server = TransportAwareFalloutTogetherServer(host="127.0.0.1", port=0)
    connection = MessageConnection()
    client = make_client(connection)

    server._send_packet(client, {"type": "transform", "x": 1.0}, broadcast=True)
    server._send_packet(client, {"type": "playerState", "characterName": "Nomad"})

    assert len(connection.messages) == 2
    transform, player_state = connection.messages
    assert transform.payload == b'{"type":"transform","x":1.0}'
    assert transform.delivery is Delivery.UNRELIABLE_SEQUENCED
    assert not transform.payload.endswith(b"\n")
    assert player_state.delivery is Delivery.RELIABLE_ORDERED
    assert player_state.payload == b'{"type":"playerState","characterName":"Nomad"}'
    assert client.packets_sent == 2
    assert client.packets_broadcast == 1
    assert server.get_stats()["packetsSent"] == 2
    assert server.get_stats()["packetsBroadcast"] == 1


def test_transport_aware_server_rejects_nonfinite_json_before_transport():
    server = TransportAwareFalloutTogetherServer(host="127.0.0.1", port=0)
    connection = MessageConnection()
    client = make_client(connection)

    with pytest.raises(ValueError):
        server._send_packet(client, {"type": "transform", "x": float("nan")})
    assert connection.messages == []
    assert server.get_stats()["packetsSent"] == 0