import json
import socketserver

__VERSION__ = "0.0.1"

# https://websockets.readthedocs.io/en/stable/reference/asyncio/server.html


class LobbyMgr:
    __instance = None

    def __new__(cls):
        if cls.__instance is None:
            cls.__instance = LobbyMgr()

        return cls.__instance


class LobbyHandler(socketserver.StreamRequestHandler):
    def handle(self):
        print(f" >>> New client {self.client} connected")
        exc = None
        try:
            self._handle_client()
        except Exception as e:
            exc = e
        finally:
            print(f" <<< Client {self.client} disconnected: {exc}")

    @property
    def client(self):
        return f"{':'.join(map(str, self.client_address))}"

    def _handle_client(self):
        self._send(type="hello", name="LobbySrv 3000", version=__VERSION__)
        while True:
            data = self.rfile.readline(10000).rstrip()
            print(f" <-- client {self.client} sent {repr(data)}")

            if not data.strip():
                continue
            try:
                data = json.loads(data)
            except json.JSONDecodeError:
                self._send_error("Could not decode message, invalid json")
                continue

            if not isinstance(data, dict) or "cmd" not in data:
                self._send_error("Invalid format in json")
                continue

            print(f"{self.client_address[0]} wrote:", data)

            match data["cmd"]:
                case "quit":
                    break
                case _:
                    self._send_error("Unknown command")

    def _send(self, **kwargs):
        data = json.dumps(kwargs).encode()
        print(f" --> sending out to {self.client}: {data}")
        self.wfile.write(json.dumps(kwargs).encode() + b"\n")

    def _send_error(self, msg: str):
        self._send(type="error", message=msg)


class LobbyServer(socketserver.ThreadingMixIn, socketserver.TCPServer):
    allow_reuse_address = True


def main():
    HOST, PORT = "localhost", 3784

    with LobbyServer((HOST, PORT), LobbyHandler) as server:
        server.serve_forever()


if __name__ == "__main__":
    main()