Lots more work on implementing battling

PkmnLib.Dynamic/Models/BattleParty.cs

@@ -10,13 +10,42 @@ public interface IBattleParty
     /// The backing Pokemon party.
     /// </summary>
     IPokemonParty Party { get; }
+
     /// <summary>
     /// Whether the party is responsible for the specified side and position.
     /// </summary>
-    bool IsResponsibleForIndex(byte side, byte position);
-    
+    bool IsResponsibleForIndex(ResponsibleIndex index);
+
     /// <summary>
     /// Whether the party has a living Pokemon left that is not in the field.
     /// </summary>
     bool HasPokemonNotInField();
+}
+
+/// <summary>
+/// A position on the battlefield that a party is responsible for.
+/// Contains the index of the side and the position on that side.
+/// </summary>
+public record struct ResponsibleIndex(byte Side, byte Position);
+
+/// <inheritdoc />
+public class BattlePartyImpl : IBattleParty
+{
+    private readonly ResponsibleIndex[] _responsibleIndices;
+
+    /// <inheritdoc cref="BattlePartyImpl"/>
+    public BattlePartyImpl(IPokemonParty party, ResponsibleIndex[] responsibleIndices)
+    {
+        Party = party;
+        _responsibleIndices = responsibleIndices;
+    }
+
+    /// <inheritdoc />
+    public IPokemonParty Party { get; }
+
+    /// <inheritdoc />
+    public bool IsResponsibleForIndex(ResponsibleIndex index) => _responsibleIndices.Contains(index);
+
+    /// <inheritdoc />
+    public bool HasPokemonNotInField() => Party.Any(x => x is { IsUsable: true, BattleData.IsOnBattlefield: false });
 }