Merge branch 'add-multiplayer-sync' into develop

1 files changed, 148 insertions, 0 deletions

diff --git a/src/SMAPI/Framework/Networking/SLidgrenServer.cs b/src/SMAPI/Framework/Networking/SLidgrenServer.cs
new file mode 100644
index 00000000..060b433b
--- /dev/null
+++ b/src/SMAPI/Framework/Networking/SLidgrenServer.cs
@@ -0,0 +1,148 @@
+using System;
+using System.Diagnostics.CodeAnalysis;
+using System.IO;
+using System.Reflection;
+using Lidgren.Network;
+using StardewModdingAPI.Framework.Reflection;
+using StardewModdingAPI.Patches;
+using StardewValley;
+using StardewValley.Network;
+
+namespace StardewModdingAPI.Framework.Networking
+{
+    /// <summary>A multiplayer server used to connect to an incoming player. This is an implementation of <see cref="LidgrenServer"/> that adds support for SMAPI's metadata context exchange.</summary>
+    internal class SLidgrenServer : LidgrenServer
+    {
+        /*********
+        ** Properties
+        *********/
+
+        /// <summary>The constructor for the internal <c>NetBufferReadStream</c> type.</summary>
+        private readonly ConstructorInfo NetBufferReadStreamConstructor = SLidgrenServer.GetNetBufferReadStreamConstructor();
+
+        /// <summary>The constructor for the internal <c>NetBufferWriteStream</c> type.</summary>
+        private readonly ConstructorInfo NetBufferWriteStreamConstructor = SLidgrenServer.GetNetBufferWriteStreamConstructor();
+
+        /// <summary>A method which reads farmer data from the given binary reader.</summary>
+        private readonly Func<BinaryReader, NetFarmerRoot> ReadFarmer;
+
+        /// <summary>A callback to raise when receiving a message. This receives the server instance, raw/parsed incoming message, and a callback to run the default logic.</summary>
+        private readonly Action<SLidgrenServer, NetIncomingMessage, IncomingMessage, Action> OnProcessingMessage;
+
+        /// <summary>A callback to raise when sending a message. This receives the server instance, outgoing connection, outgoing message, target player ID, and a callback to run the default logic.</summary>
+        private readonly Action<SLidgrenServer, NetConnection, OutgoingMessage, Action> OnSendingMessage;
+
+        /// <summary>The peer connections.</summary>
+        private readonly Bimap<long, NetConnection> Peers;
+
+        /// <summary>The underlying net server.</summary>
+        private readonly IReflectedField<NetServer> Server;
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="gameServer">The underlying game server.</param>
+        /// <param name="reflection">Simplifies access to private code.</param>
+        /// <param name="readFarmer">A method which reads farmer data from the given binary reader.</param>
+        /// <param name="onProcessingMessage">A callback to raise when receiving a message. This receives the server instance, raw/parsed incoming message, and a callback to run the default logic.</param>
+        /// <param name="onSendingMessage">A callback to raise when sending a message. This receives the server instance, outgoing connection, outgoing message, and a callback to run the default logic.</param>
+        public SLidgrenServer(IGameServer gameServer, Reflector reflection, Func<BinaryReader, NetFarmerRoot> readFarmer, Action<SLidgrenServer, NetIncomingMessage, IncomingMessage, Action> onProcessingMessage, Action<SLidgrenServer, NetConnection, OutgoingMessage, Action> onSendingMessage)
+            : base(gameServer)
+        {
+            this.ReadFarmer = readFarmer;
+            this.OnProcessingMessage = onProcessingMessage;
+            this.OnSendingMessage = onSendingMessage;
+            this.Peers = reflection.GetField<Bimap<long, NetConnection>>(this, "peers").GetValue();
+            this.Server = reflection.GetField<NetServer>(this, "server");
+        }
+
+        /// <summary>Send a message to a remote server.</summary>
+        /// <param name="connection">The network connection.</param>
+        /// <param name="message">The message to send.</param>
+        /// <remarks>This is an implementation of <see cref="LidgrenServer.sendMessage(NetConnection, OutgoingMessage)"/> which calls <see cref="OnSendingMessage"/>. This method is invoked via <see cref="LidgrenServerPatch.Prefix_LidgrenServer_SendMessage"/>.</remarks>
+        public void SendMessage(NetConnection connection, OutgoingMessage message)
+        {
+            this.OnSendingMessage(this, connection, message, () =>
+            {
+                NetServer server = this.Server.GetValue();
+                NetOutgoingMessage netMessage = server.CreateMessage();
+                using (Stream bufferWriteStream = (Stream)this.NetBufferWriteStreamConstructor.Invoke(new object[] { netMessage }))
+                using (BinaryWriter writer = new BinaryWriter(bufferWriteStream))
+                    message.Write(writer);
+
+                server.SendMessage(netMessage, connection, NetDeliveryMethod.ReliableOrdered);
+            });
+        }
+
+        /// <summary>Parse a data message from a client.</summary>
+        /// <param name="rawMessage">The raw network message to parse.</param>
+        /// <remarks>This is an implementation of <see cref="LidgrenServer.parseDataMessageFromClient"/> which calls <see cref="OnProcessingMessage"/>. This method is invoked via <see cref="LidgrenServerPatch.Prefix_LidgrenServer_ParseDataMessageFromClient"/>.</remarks>
+        [SuppressMessage("ReSharper", "AccessToDisposedClosure", Justification = "The callback is invoked synchronously.")]
+        public bool ParseDataMessageFromClient(NetIncomingMessage rawMessage)
+        {
+            // add hook to call multiplayer core
+            NetConnection peer = rawMessage.SenderConnection;
+            using (IncomingMessage message = new IncomingMessage())
+            using (Stream readStream = (Stream)this.NetBufferReadStreamConstructor.Invoke(new object[] { rawMessage }))
+            using (BinaryReader reader = new BinaryReader(readStream))
+            {
+                while (rawMessage.LengthBits - rawMessage.Position >= 8)
+                {
+                    message.Read(reader);
+                    this.OnProcessingMessage(this, rawMessage, message, () =>
+                    {
+                        if (this.Peers.ContainsLeft(message.FarmerID) && this.Peers[message.FarmerID] == peer)
+                            this.gameServer.processIncomingMessage(message);
+                        else if (message.MessageType == Multiplayer.playerIntroduction)
+                        {
+                            NetFarmerRoot farmer = this.ReadFarmer(message.Reader);
+                            this.gameServer.checkFarmhandRequest("", farmer, msg => this.SendMessage(peer, msg), () => this.Peers[farmer.Value.UniqueMultiplayerID] = peer);
+                        }
+                    });
+                }
+            }
+
+            return false;
+        }
+
+
+        /*********
+        ** Private methods
+        *********/
+        /// <summary>Get the constructor for the internal <c>NetBufferReadStream</c> type.</summary>
+        private static ConstructorInfo GetNetBufferReadStreamConstructor()
+        {
+            // get type
+            string typeName = $"StardewValley.Network.NetBufferReadStream, {Constants.GameAssemblyName}";
+            Type type = Type.GetType(typeName);
+            if (type == null)
+                throw new InvalidOperationException($"Can't find type: {typeName}");
+
+            // get constructor
+            ConstructorInfo constructor = type.GetConstructor(new[] { typeof(NetBuffer) });
+            if (constructor == null)
+                throw new InvalidOperationException($"Can't find constructor for type: {typeName}");
+
+            return constructor;
+        }
+
+        /// <summary>Get the constructor for the internal <c>NetBufferWriteStream</c> type.</summary>
+        private static ConstructorInfo GetNetBufferWriteStreamConstructor()
+        {
+            // get type
+            string typeName = $"StardewValley.Network.NetBufferWriteStream, {Constants.GameAssemblyName}";
+            Type type = Type.GetType(typeName);
+            if (type == null)
+                throw new InvalidOperationException($"Can't find type: {typeName}");
+
+            // get constructor
+            ConstructorInfo constructor = type.GetConstructor(new[] { typeof(NetBuffer) });
+            if (constructor == null)
+                throw new InvalidOperationException($"Can't find constructor for type: {typeName}");
+
+            return constructor;
+        }
+    }
+}