ProjectZ/Assets/Scripts/Level/BuildModules/ProceduralPrefabs.cs

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using Mirror;
using Unity.AI.Navigation;
using UnityEngine;
using UnityEngine.Serialization;
using Random = UnityEngine.Random;

namespace Level.BuildModules
{
    public class ProceduralPrefabs : NetworkBehaviour
    {
        public Room[] roomPrefabs;
        public Room startingRoom;

        public GameObject cubePrefab;

        private Room[,] _spawnedRooms;
        public List<Room> flattenSpawnedRooms = new();

        private int _size;

        private int _startCellX = 0;
        private int _startCellY = 0;

        public event Action levelBuilded;
        
        private CustomNetworkManager networkManager;
        
        public GameObject enemyPrefab;
        
        private List<Vector3> _enemySpawnPoses = new();
        public List<GameObject> enemyList = new();
        
        private IEnumerator Start()
        {
            if(!isServer) yield break;

            networkManager = NetworkManager.singleton.GetComponent<CustomNetworkManager>();
            
            levelBuilded += CheckGameStart;

            while (networkManager.players.Count != networkManager.maxConnections)
            {
                yield return new WaitForSecondsRealtime(1f);
            }
            
            _size = PlayerPrefs.GetInt("LevelSize");
            _spawnedRooms = new Room[_size, _size];
            _spawnedRooms[_startCellX, _startCellY] = startingRoom;

            for (int i = 0; i < _size; i++)
            {
                if (_size > 200)
                {
                    yield return new WaitForSecondsRealtime(0.1f);
                }
                
                PlaceOneRoom();
            }
            
            yield return new WaitForSecondsRealtime(1f); //Time for good build navmesh

            print("<---Rooms Spawned--->");
            
            flattenSpawnedRooms[0].GetComponent<NavMeshSurface>().BuildNavMesh();

            print("<---Surface builded--->");
            
            yield return new WaitForSecondsRealtime(3f); //Time before start game

            levelBuilded?.Invoke();
        }

        private void CheckGameStart()
        {
            if (enemyList.Count == networkManager.maxMonsters) return;

            if (networkManager.players.Count == networkManager.maxConnections)
            {
                MonsterSpawn();
                
                CubeSpawn();

                NetworkGameManager.singleton.RpcPlaySound(GameSounds.StartSound);

                print("Game started");
            }
        }

        private void CubeSpawn()
        {
            Vector3 pos = _enemySpawnPoses[Random.Range(0, _enemySpawnPoses.Count)];
            GameObject go = Instantiate(cubePrefab, pos, Quaternion.identity);
            go.GetComponent<PropBehaviour>().Original = true;

            NetworkServer.Spawn(go);
            enemyList.Add(go);
            
            print("<---Cube spawned--->");
        }

        private void MonsterSpawn()
        {
            for (int i = 0; i < networkManager.maxMonsters; i++)
            {
                Vector3 pos = _enemySpawnPoses[Random.Range(0, _enemySpawnPoses.Count)];
                GameObject go = Instantiate(enemyPrefab, pos, Quaternion.identity);

                NetworkServer.Spawn(go);
                enemyList.Add(go);
            }
                
            print("<---Monster spawned--->");
        }

        private void PlaceOneRoom()
        {
            HashSet<Vector2Int> vacantPlaces = new HashSet<Vector2Int>();
            for (int x = 0; x < _spawnedRooms.GetLength(0); x++)
            {
                for (int y = 0; y < _spawnedRooms.GetLength(1); y++)
                {
                    if (_spawnedRooms[x, y] == null) continue;

                    AddVacantPlaceIfValid(x - 1, y, vacantPlaces);
                    AddVacantPlaceIfValid(x, y - 1, vacantPlaces);
                    AddVacantPlaceIfValid(x + 1, y, vacantPlaces);
                    AddVacantPlaceIfValid(x, y + 1, vacantPlaces);
                }
            }

            Room newRoom = Instantiate(roomPrefabs[Random.Range(0, roomPrefabs.Length)], startingRoom.transform, false);
            NetworkServer.Spawn(newRoom.gameObject);

            int limit = 500;
            while (limit-- > 0)
            {
                Vector2Int position = vacantPlaces.ElementAt(Random.Range(0, vacantPlaces.Count));
                // newRoom.RotateRandomly();

                if (ConnectToSomething(newRoom, position))
                {
                    newRoom.transform.position = new Vector3(position.x - _startCellX, 0, position.y - _startCellY) * newRoom.roomSize;
                    _spawnedRooms[position.x, position.y] = newRoom;
                    flattenSpawnedRooms.Add(newRoom);
                    _enemySpawnPoses.Add(newRoom.transform.position);
                    return;
                }
            }

            NetworkServer.Destroy(newRoom.gameObject);
            Destroy(newRoom.gameObject);
        }
        
        private void AddVacantPlaceIfValid(int x, int y, HashSet<Vector2Int> vacantPlaces)
        {
            if (x >= 0 && x < _spawnedRooms.GetLength(0) && y >= 0 && y < _spawnedRooms.GetLength(1) &&
                _spawnedRooms[x, y] == null)
            {
                vacantPlaces.Add(new Vector2Int(x, y));
            }
        }

        private bool ConnectToSomething(Room room, Vector2Int p)
        {
            List<Vector2Int> neighbours = new List<Vector2Int>();

            AddNeighbourIfValid(room.DoorU, p.x, p.y + 1, Vector2Int.up, neighbours);
            AddNeighbourIfValid(room.DoorD, p.x, p.y - 1, Vector2Int.down, neighbours);
            AddNeighbourIfValid(room.DoorR, p.x + 1, p.y, Vector2Int.right, neighbours);
            AddNeighbourIfValid(room.DoorL, p.x - 1, p.y, Vector2Int.left, neighbours);
            
            AddNeighbourIfValid(room.DoorU2, p.x, p.y + 1, Vector2Int.up, neighbours);
            AddNeighbourIfValid(room.DoorD2, p.x, p.y - 1, Vector2Int.down, neighbours);
            AddNeighbourIfValid(room.DoorR2, p.x + 1, p.y, Vector2Int.right, neighbours);
            AddNeighbourIfValid(room.DoorL2, p.x - 1, p.y, Vector2Int.left, neighbours);
            
            AddNeighbourIfValid(room.DoorU3, p.x, p.y + 1, Vector2Int.up, neighbours);
            AddNeighbourIfValid(room.DoorD3, p.x, p.y - 1, Vector2Int.down, neighbours);
            AddNeighbourIfValid(room.DoorR3, p.x + 1, p.y, Vector2Int.right, neighbours);
            AddNeighbourIfValid(room.DoorL3, p.x - 1, p.y, Vector2Int.left, neighbours);

            if (neighbours.Count == 0) return false;

            Vector2Int selectedDirection = neighbours[Random.Range(0, neighbours.Count)];
            Room selectedRoom = _spawnedRooms[p.x + selectedDirection.x, p.y + selectedDirection.y];

            DisableDoors(room, selectedRoom, selectedDirection);
            room.Finish();

            return true;
        }

        private void AddNeighbourIfValid(GameObject door, int x, int y, Vector2Int direction, List<Vector2Int> neighbours)
        {
            if (door != null && x >= 0 && x <= _spawnedRooms.GetLength(0) - 1 && y >= 0 &&
                y <= _spawnedRooms.GetLength(1) - 1 && _spawnedRooms[x, y] != null)
            {
                neighbours.Add(direction);
            }
        }

        private void DisableDoors(Room room, Room selectedRoom, Vector2Int direction)
        {
            int rand = Random.Range(1, 4);

            if (direction == Vector2Int.up)
            {
                switch (rand)
                {
                    case 1 :
                        room.DisableDoor(RoomDoor.U);
                        selectedRoom.DisableDoor(RoomDoor.D);
                        break;
                    case 2 :
                        room.DisableDoor(RoomDoor.U2);
                        selectedRoom.DisableDoor(RoomDoor.D2);
                        break;
                    case 3 :
                        room.DisableDoor(RoomDoor.U3);
                        selectedRoom.DisableDoor(RoomDoor.D3);
                        break;
                }
                
            }
            else if (direction == Vector2Int.down)
            {
                switch (rand)
                {
                    case 1 :
                        room.DisableDoor(RoomDoor.D);
                        selectedRoom.DisableDoor(RoomDoor.U);
                        break;
                    case 2 :
                        room.DisableDoor(RoomDoor.D2);
                        selectedRoom.DisableDoor(RoomDoor.U2);
                        break;
                    case 3 :
                        room.DisableDoor(RoomDoor.D3);
                        selectedRoom.DisableDoor(RoomDoor.U3);
                        break;
                }
                
            }
            else if (direction == Vector2Int.right)
            {
                switch (rand)
                {
                    case 1 :
                        room.DisableDoor(RoomDoor.R);
                        selectedRoom.DisableDoor(RoomDoor.L);
                        break;
                    case 2 :
                        room.DisableDoor(RoomDoor.R2);
                        selectedRoom.DisableDoor(RoomDoor.L2);
                        break;
                    case 3 :
                        room.DisableDoor(RoomDoor.R3);
                        selectedRoom.DisableDoor(RoomDoor.L3);
                        break;
                }
            }
            else if (direction == Vector2Int.left)
            {
                switch (rand)
                {
                    case 1 :
                        room.DisableDoor(RoomDoor.L);
                        selectedRoom.DisableDoor(RoomDoor.R);
                        break;
                    case 2 :
                        room.DisableDoor(RoomDoor.L2);
                        selectedRoom.DisableDoor(RoomDoor.R2);
                        break;
                    case 3 :
                        room.DisableDoor(RoomDoor.L3);
                        selectedRoom.DisableDoor(RoomDoor.R3);
                        break;
                }
                
            }
        }
    }
}