from __future__ import annotations

import asyncio
import json

from engine.network.protocol import DEFAULT_PORT, encode_message


class GameClient:
    """Minimal TCP client for GameServer: sends hello/move, receives broadcasts from other players."""

    def __init__(self, entity_id: str, name: str, host: str = "127.0.0.1", port: int = DEFAULT_PORT):
        self.entity_id = entity_id
        self.name = name
        self.host = host
        self.port = port
        self._reader: asyncio.StreamReader | None = None
        self._writer: asyncio.StreamWriter | None = None

    async def connect(self) -> None:
        self._reader, self._writer = await asyncio.open_connection(self.host, self.port)
        await self.send({"type": "hello", "entity_id": self.entity_id, "name": self.name})

    async def send(self, message: dict) -> None:
        assert self._writer is not None
        self._writer.write(encode_message(message))
        await self._writer.drain()

    async def send_move(self, map_id: str, x: int, y: int, z: int) -> None:
        await self.send({"type": "move", "entity_id": self.entity_id, "map_id": map_id, "x": x, "y": y, "z": z})

    async def receive(self) -> dict | None:
        assert self._reader is not None
        line = await self._reader.readline()
        if not line:
            return None
        return json.loads(line)

    async def close(self) -> None:
        if self._writer is not None:
            self._writer.close()
            await self._writer.wait_closed()
            self._writer = None