project-reset/Assets/Scripts/Core/GameManager.cs

using System;
using System.Collections.Generic;
using Reset.Core.Tools;
using Unity.Netcode;
using UnityEngine;
using UnityEngine.InputSystem;
using UnityEngine.InputSystem.Users;

namespace Reset{
    public static class GameManager{
        public static GameObject UI;
        public static GameObject Camera;
        public static GameObject Input;
        public static SessionManager Session;

        private static GameObject player;

        public static GameObject Player{
            get{ return player; }
            set{ player = value; }
        }
        
        [RuntimeInitializeOnLoadMethod]
        static void Reset(){
            player = null;
        }

        [RuntimeInitializeOnLoadMethod]
        static void PopulateSceneReferences(){
            try {
                UI = GameObject.Find("UICanvas");
                Camera = GameObject.Find("CameraGroup");
                Input = GameObject.Find("InputManager");
            } catch (Exception e) {
                Console.WriteLine(e);
                throw;
            }
        }
        
        public static void AttachControllerToPlayer(InputDevice device){
            if (!Player) {
                throw new Exception(message: "There is no player to attach this new input device to.");
            }

            InputUser playerUser = Player.GetComponent<PlayerInput>().user;
            playerUser = InputUser.PerformPairingWithDevice(device, playerUser, InputUserPairingOptions.UnpairCurrentDevicesFromUser);
        }

        public static GameObject FindNewPlayer(){
            var allPlayers = GameObject.FindGameObjectsWithTag("Player");
            for (int i = 0; i < allPlayers.Length; i++) {
                if (allPlayers[i].GetComponent<Player>() && allPlayers[i].GetComponent<NetworkObject>().IsLocalPlayer) {
                    return allPlayers[i];
                }
            }

            return null;
        }

        public static void RequestNewController(){
            try {
                GameObject.Find("Input Selector").GetComponent<InputFinder>().AwaitNewInput();
            } catch (Exception e) {
                Debug.LogError($"Can't request a new controller: {e.Message}");
            }
        }

        public static void ClearCurrentController(){
            InputUser playerUser = Player.GetComponent<PlayerInput>().user;
            playerUser.UnpairDevices();
        }

    }
}