modernuo/Projects/UOContent/Spells/Targeting/SpellTarget.cs

using Server.Targeting;

namespace Server.Spells;

public class SpellTarget<T> : Target, ISpellTarget<T> where T : class, IPoint3D
{
    private static readonly bool _canTargetStatic = typeof(T).IsAssignableFrom(typeof(StaticTarget));
    private static readonly bool _canTargetMobile = typeof(T).IsAssignableFrom(typeof(Mobile));
    private static readonly bool _canTargetItem = typeof(T).IsAssignableFrom(typeof(Item));

    private readonly bool _retryOnLos;
    protected readonly ITargetingSpell<T> _spell;

    public SpellTarget(
        ITargetingSpell<T> spell,
        TargetFlags flags,
        bool retryOnLos = false
    ) : this(spell, false, flags, retryOnLos)
    {
    }

    public SpellTarget(
        ITargetingSpell<T> spell,
        bool allowGround = false,
        TargetFlags flags = TargetFlags.None,
        bool retryOnLos = false
    ) : base(spell.TargetRange, allowGround, flags)
    {
        _spell = spell;
        _retryOnLos = retryOnLos;
    }

    public ITargetingSpell<T> Spell => _spell;

    protected override bool CanTarget(Mobile from, StaticTarget staticTarget, ref Point3D loc, ref Map map)
        => base.CanTarget(from, staticTarget, ref loc, ref map) && _canTargetStatic;

    protected override bool CanTarget(Mobile from, Mobile mobile, ref Point3D loc, ref Map map) =>
        base.CanTarget(from, mobile, ref loc, ref map) && _canTargetMobile;

    protected override bool CanTarget(Mobile from, Item item, ref Point3D loc, ref Map map) =>
        base.CanTarget(from, item, ref loc, ref map) && _canTargetItem;

    protected override void OnCantSeeTarget(Mobile from, object o)
    {
        from.SendLocalizedMessage(500237); // Target can not be seen.
    }

    protected override void OnTarget(Mobile from, object o) => _spell.Target(o as T);

    protected override void OnTargetOutOfLOS(Mobile from, object o)
    {
        if (!_retryOnLos)
        {
            return;
        }

        from.SendLocalizedMessage(501943); // Target cannot be seen. Try again.
        from.Target = new SpellTarget<T>(_spell, AllowGround, Flags, true);
        from.Target.BeginTimeout(from, TimeoutTime - Core.TickCount);
    }

    protected override void OnTargetFinish(Mobile from) => _spell?.FinishSequence();
}