Fixes and reworking of item use

PkmnLib.Dynamic/Models/ItemTargetType.cs

@@ -0,0 +1,67 @@
+namespace PkmnLib.Dynamic.Models;
+
+/// <summary>
+/// Types of targets an item can have.
+/// </summary>
+[Flags]
+public enum ItemTargetType
+{
+    /// <summary>
+    /// The item does not require a target.
+    /// </summary>
+    None = 0,
+
+    /// <summary>
+    /// The item targets Pokémon that are part of the user's own team.
+    /// </summary>
+    OwnPokemon = 1,
+
+    /// <summary>
+    /// The item targets allied Pokémon.
+    /// </summary>
+    AllyPokemon = 2,
+
+    /// <summary>
+    /// The item targets opposing Pokémon.
+    /// </summary>
+    FoePokemon = 4,
+}
+
+/// <summary>
+/// Helper methods for ItemTargetType.
+/// </summary>
+public static class ItemTargetTypeHelpers
+{
+    /// <summary>
+    /// Determines if the given target is valid based on the ItemTargetType.
+    /// </summary>
+    public static bool IsValidTarget(this ItemTargetType targetType, IBattle battle, IPokemon user, IPokemon target)
+    {
+        if (targetType == ItemTargetType.None)
+            return true;
+
+        if (targetType.HasFlag(ItemTargetType.OwnPokemon))
+        {
+            var userParty = battle.Parties.FirstOrDefault(x => x.Party.Contains(user));
+            var targetParty = battle.Parties.FirstOrDefault(x => x.Party.Contains(target));
+            if (userParty is not null && targetParty is not null && userParty == targetParty)
+                return true;
+        }
+
+        if (targetType.HasFlag(ItemTargetType.AllyPokemon))
+        {
+            if (user.BattleData?.BattleSide == target.BattleData?.BattleSide)
+                return true;
+        }
+
+        if (targetType.HasFlag(ItemTargetType.FoePokemon))
+        {
+            var userParty = battle.Parties.FirstOrDefault(x => x.Party.Contains(user));
+            var targetParty = battle.Parties.FirstOrDefault(x => x.Party.Contains(target));
+            if (userParty is not null && targetParty is not null && userParty != targetParty)
+                return true;
+        }
+
+        return false;
+    }
+}