Ragon/Ragon.Client/Sources/Handler/SnapshotHandler.cs

/*
 * Copyright 2023-2024 Eduard Kargin <kargin.eduard@gmail.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


using System.Diagnostics;
using Ragon.Protocol;

namespace Ragon.Client;

internal class SnapshotHandler : IHandler
{
  private readonly IRagonEntityListener _entityListener;
  private readonly RagonClient _client;
  private readonly RagonListenerList _listenerList;
  private readonly RagonEntityCache _entityCache;
  private readonly RagonPlayerCache _playerCache;

  public SnapshotHandler(
    RagonClient ragonClient,
    RagonListenerList listenerList,
    RagonEntityCache entityCache,
    RagonPlayerCache playerCache,
    IRagonEntityListener entityListener
  )
  {
    _client = ragonClient;
    _entityListener = entityListener;
    _listenerList = listenerList;
    _entityCache = entityCache;
    _playerCache = playerCache;
  }

  public void Handle(RagonBuffer buffer)
  {
    var entities = new List<RagonEntity>();
    var dynamicEntities = buffer.ReadUShort();
    RagonLog.Trace("Dynamic Entities: " + dynamicEntities);
    for (var i = 0; i < dynamicEntities; i++)
    {
      var entityType = buffer.ReadUShort();
      var entityId = buffer.ReadUShort();
      var ownerPeerId = buffer.ReadUShort();
      var payloadSize = buffer.ReadUShort();

      var player = _playerCache.GetPlayerByPeer(ownerPeerId);
      if (player == null)
      {
        RagonLog.Error($"Player not found with peerId: {ownerPeerId}");

        _playerCache.Dump();
        return;
      }

      var hasAuthority = _playerCache.Local.Id == player.Id;
      var entity = _entityCache.TryGetEntity(0, entityType, 0, entityId, hasAuthority, out _);
      var payload = RagonPayload.Empty;
      if (payloadSize > 0)
      {
        payload = new RagonPayload(payloadSize);
        payload.Read(buffer);
      }

      entity.Prepare(_client, entityId, entityType, hasAuthority, player, payload);

      _entityListener.OnEntityCreated(entity);

      entity.Read(buffer);

      entities.Add(entity);
    }

    var staticEntities = buffer.ReadUShort();
    RagonLog.Trace("Scene Entities: " + staticEntities);
    for (var i = 0; i < staticEntities; i++)
    {
      var entityType = buffer.ReadUShort();
      var entityId = buffer.ReadUShort();
      var staticId = buffer.ReadUShort();
      var ownerPeerId = buffer.ReadUShort();
      var payloadSize = buffer.ReadUShort();

      var player = _playerCache.GetPlayerByPeer(ownerPeerId);
      if (player == null)
      {
        RagonLog.Error($"Player not found with peerId: {ownerPeerId}");

        _playerCache.Dump();
        return;
      }

      var hasAuthority = _playerCache.Local.Id == player.Id;
      var entity = _entityCache.TryGetEntity(0, entityType, staticId, entityId, hasAuthority, out _);

      entity.Prepare(_client, entityId, entityType, hasAuthority, player, RagonPayload.Empty);
      entity.Read(buffer);

      entities.Add(entity);
    }
    
    foreach (var entity in entities)
      entity.Attach();

    _listenerList.OnSceneLoaded();
  }
}