From a07549f013b99efe3477d9bd2f78f42754cd24ed Mon Sep 17 00:00:00 2001
From: Kurt <kaphotics@gmail.com>
Date: Sun, 6 Jun 2021 23:36:59 -0700
Subject: [PATCH] Extract sketch valid check

GetCanKnowMove should be checking for Smeargle knowing thousand arrows/waves.
GetNeededMoves should also return 1ka/1kw for needed moves, and then no encounters.

All uses of InvalidSketch are behind that method, so any future Smeargle modifications (like sketching a dummied move) will be checked (yay BDSP considerations).
---
 .../Moveset/EncounterMovesetGenerator.cs      |  2 +-
 .../Verifiers/VerifyCurrentMoves.cs           |  6 +++---
 PKHeX.Core/Legality/Tables/Tables.cs          | 20 +++++++++++++++++--
 .../Legality/Verifiers/MemoryPermissions.cs   |  2 +-
 4 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/PKHeX.Core/Legality/Encounters/Generator/Moveset/EncounterMovesetGenerator.cs b/PKHeX.Core/Legality/Encounters/Generator/Moveset/EncounterMovesetGenerator.cs
index 49f58b5f2..0bf7ebba7 100644
--- a/PKHeX.Core/Legality/Encounters/Generator/Moveset/EncounterMovesetGenerator.cs
+++ b/PKHeX.Core/Legality/Encounters/Generator/Moveset/EncounterMovesetGenerator.cs
@@ -150,7 +150,7 @@ public static IEnumerable<IEncounterable> GenerateVersionEncounters(PKM pk, IEnu
         private static int[] GetNeededMoves(PKM pk, IEnumerable<int> moves, IReadOnlyList<EvoCriteria> chain)
         {
             if (pk.Species == (int)Species.Smeargle)
-                return moves.Intersect(Legal.InvalidSketch).ToArray(); // Can learn anything
+                return moves.Where(z => !Legal.IsValidSketch(z, pk.Format)).ToArray(); // Can learn anything
 
             // Roughly determine the generation the PKM is originating from
             var ver = pk.Version;
diff --git a/PKHeX.Core/Legality/Encounters/Verifiers/VerifyCurrentMoves.cs b/PKHeX.Core/Legality/Encounters/Verifiers/VerifyCurrentMoves.cs
index 527e24e60..c98f1b73a 100644
--- a/PKHeX.Core/Legality/Encounters/Verifiers/VerifyCurrentMoves.cs
+++ b/PKHeX.Core/Legality/Encounters/Verifiers/VerifyCurrentMoves.cs
@@ -136,9 +136,9 @@ private static CheckMoveResult[] ParseMovesSketch(PKM pkm, IReadOnlyList<int> cu
             for (int i = 0; i < 4; i++)
             {
                 var move = currentMoves[i];
-                res[i] = Legal.InvalidSketch.Contains(move) || (pkm.Format is 6 && move is (int)Move.ThousandArrows or (int)Move.ThousandWaves)
-                    ? new CheckMoveResult(Unknown, pkm.Format, Invalid, LMoveSourceInvalidSketch, CurrentMove)
-                    : new CheckMoveResult(Sketch, pkm.Format, CurrentMove);
+                res[i] = Legal.IsValidSketch(move, pkm.Format)
+                    ? new CheckMoveResult(Sketch, pkm.Format, CurrentMove)
+                    : new CheckMoveResult(Unknown, pkm.Format, Invalid, LMoveSourceInvalidSketch, CurrentMove);
             }
 
             return res;
diff --git a/PKHeX.Core/Legality/Tables/Tables.cs b/PKHeX.Core/Legality/Tables/Tables.cs
index 3c666f0cf..44f7736f9 100644
--- a/PKHeX.Core/Legality/Tables/Tables.cs
+++ b/PKHeX.Core/Legality/Tables/Tables.cs
@@ -81,9 +81,9 @@ public static partial class Legal
         };
 
         /// <summary>
-        /// Moves that can not be obtained by using Sketch with Smeargle.
+        /// Moves that can not be obtained by using Sketch with Smeargle in any game.
         /// </summary>
-        internal static readonly HashSet<int> InvalidSketch = new(Z_Moves)
+        private static readonly HashSet<int> InvalidSketch = new(Z_Moves)
         {
             // Can't Sketch
             (int)Struggle,
@@ -93,6 +93,22 @@ public static partial class Legal
             (int)LightofRuin,
         };
 
+        /// <summary>
+        /// Checks if Sketch can obtain the <see cref="move"/> in the requested <see cref="generation"/>
+        /// </summary>
+        /// <remarks>Doesn't bounds check the <see cref="generation"/> for max move ID.</remarks>
+        /// <param name="move">Move ID</param>
+        /// <param name="generation">Generation to check</param>
+        /// <returns>True if can be sketched, false if not available.</returns>
+        public static bool IsValidSketch(int move, int generation)
+        {
+            if (InvalidSketch.Contains(move))
+                return false;
+            if (generation is 6 && move is ((int)ThousandArrows or (int)ThousandWaves))
+                return false;
+            return true;
+        }
+
         /// <summary>
         /// Species that are from Mythical Distributions (disallowed species for competitive rulesets)
         /// </summary>
diff --git a/PKHeX.Core/Legality/Verifiers/MemoryPermissions.cs b/PKHeX.Core/Legality/Verifiers/MemoryPermissions.cs
index 00fa2a8e7..75d3b4ad0 100644
--- a/PKHeX.Core/Legality/Verifiers/MemoryPermissions.cs
+++ b/PKHeX.Core/Legality/Verifiers/MemoryPermissions.cs
@@ -105,7 +105,7 @@ public static bool GetCanRelearnMove(PKM pkm, int move, int generation, IReadOnl
         private static bool GetCanKnowMove(PKM pkm, int move, int generation, IReadOnlyList<IReadOnlyList<EvoCriteria>> evos, GameVersion version = GameVersion.Any)
         {
             if (pkm.Species == (int)Smeargle)
-                return !Legal.InvalidSketch.Contains(move);
+                return Legal.IsValidSketch(move, generation);
 
             if (generation >= 8 && MoveEgg.GetIsSharedEggMove(pkm, generation, move))
                 return true;