ModernUO/Projects/Server/Network/Packets/IncomingTargetingPackets.cs

/*************************************************************************
 * ModernUO                                                              *
 * Copyright 2019-2022 - ModernUO Development Team                       *
 * Email: hi@modernuo.com                                                *
 * File: IncomingTargetingPackets.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 Server.Diagnostics;
using Server.Targeting;

namespace Server.Network;

public static class IncomingTargetingPackets
{
    public static unsafe void Configure()
    {
        IncomingPackets.Register(0x6C, 19, true, &TargetResponse);
    }

    public static void TargetResponse(NetState state, CircularBufferReader reader, int packetLength)
    {
        int type = reader.ReadByte();
        var targetID = reader.ReadInt32();
        int flags = reader.ReadByte();
        var serial = (Serial)reader.ReadUInt32();
        int x = reader.ReadInt16();
        int y = reader.ReadInt16();
        reader.ReadByte();
        int z = reader.ReadSByte();
        int graphic = reader.ReadUInt16();

        if (targetID == unchecked((int)0xDEADBEEF))
        {
            return;
        }

        var from = state.Mobile;

        var t = from.Target;

        if (t == null)
        {
            return;
        }

        var prof = TargetProfile.Acquire(t.GetType());
        prof?.Start();

        try
        {
            if (x == -1 && y == -1 && !serial.IsValid)
            {
                // User pressed escape
                t.Cancel(from, TargetCancelType.Canceled);
            }
            else if (t.TargetID != targetID)
            {
                // Sanity, prevent fake target
            }
            else
            {
                object toTarget;

                if (type == 1)
                {
                    if (graphic == 0)
                    {
                        toTarget = new LandTarget(new Point3D(x, y, z), from.Map);
                    }
                    else
                    {
                        var map = from.Map;

                        if (map == null || map == Map.Internal)
                        {
                            t.Cancel(from, TargetCancelType.Canceled);
                            return;
                        }
                        else
                        {
                            var tiles = map.Tiles.GetStaticTiles(x, y, !t.DisallowMultis);

                            var valid = false;

                            if (state.HighSeas)
                            {
                                var id = TileData.ItemTable[graphic & TileData.MaxItemValue];
                                if (id.Surface)
                                {
                                    z -= id.Height;
                                }
                            }

                            for (var i = 0; !valid && i < tiles.Length; ++i)
                            {
                                if (tiles[i].Z == z && tiles[i].ID == graphic)
                                {
                                    valid = true;
                                }
                            }

                            if (!valid)
                            {
                                t.Cancel(from, TargetCancelType.Canceled);
                                return;
                            }
                            else
                            {
                                toTarget = new StaticTarget(new Point3D(x, y, z), graphic);
                            }
                        }
                    }
                }
                else if (serial.IsMobile)
                {
                    toTarget = World.FindMobile(serial);
                }
                else if (serial.IsItem)
                {
                    toTarget = World.FindItem(serial);
                }
                else
                {
                    t.Cancel(from, TargetCancelType.Canceled);
                    return;
                }

                t.Invoke(from, toTarget);
            }
        }
        finally
        {
            prof?.Finish();
        }
    }
}