fix(network): Adds ConnectUO (#551)

- [X] Adds ability to create new protocol extension packets
- [X] Adds freeshard protocol extension support (packet 0xF1)
- [X] Adds ConnectUO support
- [X] Adds arbitrary read for `CircularBufferReader` and `SpanReader`

Projects/UOContent/Network/MapUO.cs

@@ -0,0 +1,164 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright (C) 2019-2021 - ModernUO Development Team                   *
+ * Email: hi@modernuo.com                                                *
+ * File: MapUO.cs                                                        *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it 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.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System;
+using System.Buffers;
+using System.IO;
+using Server.Engines.PartySystem;
+using Server.Guilds;
+
+namespace Server.Network
+{
+    public static class MapUO
+    {
+        private static PacketHandler[] _handlers;
+
+        public static void Configure()
+        {
+            _handlers = ProtocolExtensions.Register(0xF0);
+
+            Register(0x00, true, QueryPartyMemberLocations);
+            Register(0x01, true, QueryGuildMemberLocations);
+        }
+
+        public static void Register(int cmd, bool ingame, OnPacketReceive onReceive) =>
+            _handlers[cmd] = new PacketHandler(cmd, 0, ingame, onReceive);
+
+        public static void QueryGuildMemberLocations(NetState state, CircularBufferReader reader, ref int packetLength)
+        {
+            Mobile from = state.Mobile;
+
+            state.SendGuildMemberLocations(from, from.Guild as Guild, reader.ReadBoolean());
+        }
+
+        public static void QueryPartyMemberLocations(NetState state, CircularBufferReader reader, ref int packetLength)
+        {
+            Mobile from = state.Mobile;
+            var party = Party.Get(from);
+
+            if (party != null)
+            {
+                state.SendPartyMemberLocations(from, party);
+            }
+        }
+
+        public static void SendGuildMemberLocations(this NetState ns, Mobile from, Guild guild, bool sendLocations)
+        {
+            if (ns == null)
+            {
+                return;
+            }
+
+            var count = guild?.Members.Count ?? 0;
+            var maxLength = 9 + (count > 1 ? (count - 1) * (sendLocations ? 10 : 4) : 0);
+            var writer = new SpanWriter(stackalloc byte[maxLength]);
+            writer.Write((byte)0xF0); // Packet ID
+            writer.Seek(2, SeekOrigin.Current);
+            writer.Write((byte)0x02); // Command
+            writer.Write(count > 0 && sendLocations);
+
+            bool sendPacket = false;
+            for (var i = 0; i < count; i++)
+            {
+                var m = guild!.Members[i];
+
+                if (m?.NetState == null || m == from)
+                {
+                    continue;
+                }
+
+                if (sendLocations && Utility.InUpdateRange(from, m) && from.CanSee(m))
+                {
+                    continue;
+                }
+
+                sendPacket = true;
+                writer.Write(m.Serial);
+
+                if (sendLocations)
+                {
+                    writer.Write((short)m.X);
+                    writer.Write((short)m.Y);
+                    writer.Write((byte)(m.Map?.MapID ?? 0));
+
+                    if (m.Alive)
+                    {
+                        writer.Write((byte)(m.Hits * 100 / Math.Max(m.HitsMax, 1)));
+                    }
+                    else
+                    {
+                        writer.Write((byte)0);
+                    }
+                }
+            }
+
+            if (!sendPacket)
+            {
+                return;
+            }
+
+            writer.Write(0);
+            writer.WritePacketLength();
+            ns.Send(writer.Span);
+        }
+
+        public static void SendPartyMemberLocations(this NetState ns, Mobile from, Party party)
+        {
+            if (ns == null)
+            {
+                return;
+            }
+
+            var count = party?.Members.Count ?? 0;
+            var maxLength = 9 + (count > 1 ? (count - 1) * 9 : 0);
+            var writer = new SpanWriter(stackalloc byte[maxLength]);
+            writer.Write((byte)0xF0); // Packet ID
+            writer.Seek(2, SeekOrigin.Current);
+            writer.Write((byte)0x01); // Command
+
+            bool sendPacket = false;
+            for (var i = 0; i < count; i++)
+            {
+                var pmi = party!.Members[i];
+                Mobile mob = pmi?.Mobile;
+
+                if (mob?.NetState == null || mob == from)
+                {
+                    continue;
+                }
+
+                if (Utility.InUpdateRange(from, mob) && from.CanSee(mob))
+                {
+                    continue;
+                }
+
+                sendPacket = true;
+                writer.Write(mob.Serial);
+                writer.Write((short)mob.X);
+                writer.Write((short)mob.Y);
+                writer.Write((byte)(mob.Map?.MapID ?? 0));
+            }
+
+            if (!sendPacket)
+            {
+                return;
+            }
+
+            writer.Write(0);
+            writer.WritePacketLength();
+            ns.Send(writer.Span);
+        }
+    }
+}