using System;
using Server.Items;
using Server.Targeting;
using Server.Utilities;

namespace Server.Commands
{
    public static class Dupe
    {
        public static void Initialize()
        {
            CommandSystem.Register("Dupe", AccessLevel.GameMaster, Dupe_OnCommand);
            CommandSystem.Register("DupeInBag", AccessLevel.GameMaster, DupeInBag_OnCommand);
        }

        [Usage("Dupe [amount]")]
        [Description("Dupes a targeted item.")]
        private static void Dupe_OnCommand(CommandEventArgs e)
        {
            var amount = 1;
            if (e.Length >= 1)
            {
                amount = e.GetInt32(0);
            }

            e.Mobile.Target = new DupeTarget(false, amount > 0 ? amount : 1);
            e.Mobile.SendMessage("What do you wish to dupe?");
        }

        [Usage("DupeInBag <count>")]
        [Description("Dupes an item at it's current location (count) number of times.")]
        private static void DupeInBag_OnCommand(CommandEventArgs e)
        {
            var amount = 1;
            if (e.Length >= 1)
            {
                amount = e.GetInt32(0);
            }

            e.Mobile.Target = new DupeTarget(true, amount > 0 ? amount : 1);
            e.Mobile.SendMessage("What do you wish to dupe?");
        }

        public static void CopyProperties(Item dest, Item src)
        {
            var props = src.GetType().GetProperties();

            for (var i = 0; i < props.Length; i++)
            {
                var p = props[i];
                try
                {
                    // Do not set the parent since it screws up mobile/container totals and weights.
                    if (p.CanRead && p.CanWrite && p.Name != "Parent")
                    {
                        p.SetValue(dest, p.GetValue(src, null), null);
                    }
                }
                catch
                {
                    // ignored
                }
            }
        }

        private class DupeTarget : Target
        {
            private readonly int m_Amount;
            private readonly bool m_InBag;

            public DupeTarget(bool inbag, int amount)
                : base(15, false, TargetFlags.None)
            {
                m_InBag = inbag;
                m_Amount = amount;
            }

            protected override void OnTarget(Mobile from, object targ)
            {
                var done = false;
                if (!(targ is Item))
                {
                    from.SendMessage("You can only dupe items.");
                    return;
                }

                CommandLogging.WriteLine(
                    from,
                    $"{from.AccessLevel} {CommandLogging.Format(from)} duping {CommandLogging.Format(targ)} (inBag={m_InBag}; amount={m_Amount})"
                );

                var copy = (Item)targ;
                Container pack = null;

                if (m_InBag)
                {
                    pack = copy.Parent switch
                    {
                        Container cont => cont,
                        Mobile m       => m.Backpack,
                        _              => pack
                    };
                }
                else
                {
                    pack = from.Backpack;
                }

                var c = copy.GetType().GetConstructor();
                if (c != null)
                {
                    var paramList = c.GetParameters();
                    var args = paramList.Length == 0 ? null : new object[paramList.Length];
                    if (args != null)
                    {
                        Array.Fill(args, Type.Missing);
                    }

                    try
                    {
                        from.SendMessage($"Duping {m_Amount}...");
                        for (var i = 0; i < m_Amount; i++)
                        {
                            if (c.Invoke(args) is Item newItem)
                            {
                                CopyProperties(newItem, copy);
                                copy.OnAfterDuped(newItem);

                                if (pack != null)
                                {
                                    pack.DropItem(newItem);
                                }
                                else
                                {
                                    newItem.MoveToWorld(from.Location, from.Map);
                                }

                                newItem.UpdateTotals();
                                newItem.InvalidateProperties();
                                newItem.Delta(ItemDelta.Update);

                                CommandLogging.WriteLine(
                                    from,
                                    $"{from.AccessLevel} {CommandLogging.Format(from)} duped {CommandLogging.Format(targ)} creating {CommandLogging.Format(newItem)}"
                                );
                            }
                        }

                        from.SendMessage("Done");
                        done = true;
                    }
                    catch
                    {
                        from.SendMessage("Error!");
                        return;
                    }
                }

                if (!done)
                {
                    from.SendMessage("Unable to dupe. Item must have a constructor with zero required parameters.");
                }
            }
        }
    }
}