Initial commit: OpenRA game engine

Fork from OpenRA/OpenRA with one-click launch script (start-ra.cmd)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

OpenRA.Game/Network/ReplayConnection.cs

@@ -0,0 +1,136 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * This file is part of OpenRA, which is free software. It is made
+ * available to you under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version. For more
+ * information, see COPYING.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using OpenRA.FileFormats;
+
+namespace OpenRA.Network
+{
+	public sealed class ReplayConnection : IConnection
+	{
+		sealed class Chunk
+		{
+			public int Frame;
+			public (int ClientId, byte[] Packet)[] Packets;
+		}
+
+		readonly Queue<Chunk> chunks = [];
+		readonly Queue<(int Frame, int SyncHash, ulong DefeatState)> sync = [];
+		readonly int orderLatency;
+
+		public readonly int TickCount;
+		public readonly int FinalGameTick;
+		public readonly bool IsValid;
+		public readonly Session LobbyInfo;
+		public readonly string Filename;
+
+		public ReplayConnection(string replayFilename)
+		{
+			Filename = replayFilename;
+			FinalGameTick = ReplayMetadata.Read(replayFilename).GameInfo.FinalGameTick;
+
+			// Parse replay data into a struct that can be fed to the game in chunks
+			// to avoid issues with all immediate orders being resolved on the first tick.
+			using (var rs = File.OpenRead(replayFilename))
+			{
+				var packets = new List<(int ClientId, byte[] Packet)>();
+				var chunk = new Chunk();
+				while (rs.Position < rs.Length)
+				{
+					var client = rs.ReadInt32();
+					if (client == ReplayMetadata.MetaStartMarker)
+						break;
+
+					var packetLen = rs.ReadInt32();
+					var packet = rs.ReadBytes(packetLen);
+					var frame = BitConverter.ToInt32(packet, 0);
+					packets.Add((client, packet));
+
+					if (packet.Length > 4 && (packet[4] == (byte)OrderType.Disconnect || packet[4] == (byte)OrderType.SyncHash))
+						continue;
+
+					if (frame == 0)
+					{
+						// Parse replay metadata from orders stream
+						if (OrderIO.TryParseOrderPacket(packet, out var orders))
+						{
+							foreach (var o in orders.Orders.GetOrders(null))
+							{
+								if (o.OrderString == "StartGame")
+									IsValid = true;
+								else if (o.OrderString == "SyncInfo" && !IsValid)
+									LobbyInfo = Session.Deserialize(o.TargetString, o.OrderString);
+							}
+						}
+					}
+					else
+					{
+						// Regular order - finalize the chunk
+						chunk.Frame = frame;
+						chunk.Packets = packets.ToArray();
+						packets.Clear();
+						chunks.Enqueue(chunk);
+						chunk = new Chunk();
+
+						TickCount = Math.Max(TickCount, frame);
+					}
+				}
+			}
+
+			var gameSpeeds = Game.ModData.GetOrCreate<GameSpeeds>();
+			var gameSpeedName = LobbyInfo.GlobalSettings.OptionOrDefault("gamespeed", gameSpeeds.DefaultSpeed);
+			orderLatency = gameSpeeds.Speeds[gameSpeedName].OrderLatency;
+		}
+
+		void IConnection.StartGame() { }
+
+		// Do nothing: ignore locally generated orders
+		void IConnection.Send(int frame, IEnumerable<Order> orders) { }
+		void IConnection.SendImmediate(IEnumerable<Order> orders) { }
+
+		void IConnection.SendSync(int frame, int syncHash, ulong defeatState)
+		{
+			sync.Enqueue((frame, syncHash, defeatState));
+		}
+
+		void IConnection.Receive(OrderManager orderManager)
+		{
+			while (sync.Count != 0)
+				orderManager.ReceiveSync(sync.Dequeue());
+
+			while (chunks.Count != 0 && chunks.Peek().Frame <= orderManager.NetFrameNumber + orderLatency)
+			{
+				foreach (var o in chunks.Dequeue().Packets)
+				{
+					if (OrderIO.TryParseDisconnect(o, out var disconnect))
+						orderManager.ReceiveDisconnect(disconnect.ClientId, disconnect.Frame);
+					else if (OrderIO.TryParseSync(o.Packet, out var sync))
+						orderManager.ReceiveSync(sync);
+					else if (OrderIO.TryParseOrderPacket(o.Packet, out var orders))
+					{
+						if (orders.Frame == 0)
+							orderManager.ReceiveImmediateOrders(o.ClientId, orders.Orders);
+						else
+							orderManager.ReceiveOrders(o.ClientId, orders);
+					}
+					else
+						throw new InvalidDataException($"Received unknown packet from client {o.ClientId} with length {o.Packet.Length}");
+				}
+			}
+		}
+
+		int IConnection.LocalClientId => -1;
+
+		void IDisposable.Dispose() { }
+	}
+}