Extract some reused logic

Put the methods in Tables4; kinda breaks the 'only arrays here' rule but
they only reference values in this file(partial class).

PKHeX.Core/Legality/Encounters/Information/EncounterSuggestion.cs

@@ -170,11 +170,7 @@ namespace PKHeX.Core
                 return -1;
 
             if (pkm.Format >= 5) // Transporter
-            {
+                return Legal.GetTransfer45MetLocation(pkm);
-                return pkm.Gen4 && pkm.FatefulEncounter && Legal.CrownBeasts.Contains(pkm.Species)
-                    ? (pkm.Species == 251 ? Legal.Transfer4_CelebiUnused : Legal.Transfer4_CrownUnused) // Celebi : Beast
-                    : Legal.Transfer4; // Pokétransfer (not Crown)
-            }
             return -1;
         }
     }

PKHeX.Core/Legality/Tables4.cs

@@ -153,7 +153,7 @@ namespace PKHeX.Core
 
         internal static readonly HashSet<int> HM_HGSS = new HashSet<int>
         {
-            015, 019, 057, 070, 250, 249, 127, 431 // Whirlpool(HGSS) 
+            015, 019, 057, 070, 250, 249, 127, 431 // Whirlpool(HGSS)
         };
 
         internal static readonly HashSet<int> HM_DPPt = new HashSet<int>
@@ -161,7 +161,6 @@ namespace PKHeX.Core
             015, 019, 057, 070, 432, 249, 127, 431 // Defog(DPPt)
         };
 
-
         internal static readonly HashSet<int> HM_4_RemovePokeTransfer = new HashSet<int>
         {
             015, 019, 057, 070, 249, 127, 431 // Defog(DPPt) & Whirlpool(HGSS) excluded
@@ -211,7 +210,6 @@ namespace PKHeX.Core
         };
 
         internal static readonly bool[] ReleasedHeldItems_4 = Enumerable.Range(0, MaxItemID_4_HGSS+1).Select(i => HeldItems_HGSS.Contains((ushort)i) && !UnreleasedItems_4.Contains(i)).ToArray();
-        internal static readonly HashSet<int> CrownBeasts = new HashSet<int> { 251, 243, 244, 245 };
 
         internal static readonly int[] Tutors_4 =
         {
@@ -282,5 +280,42 @@ namespace PKHeX.Core
         {
             2000, 2002, 2009, 2010, 2011, 2013, 2014
         };
+
+        internal static int GetTransfer45MetLocation(PKM pk5)
+        {
+            if (pk5.Gen4 && pk5.FatefulEncounter)
+            {
+                var spec = pk5.Species;
+                if (spec == 251) // Celebi
+                    return Transfer4_CelebiUnused;
+                if (243 <= spec && spec <= 245) // Beast
+                    return Transfer4_CrownUnused;
+            }
+            return Transfer4; // Pokétransfer (not Crown);
+        }
+
+        internal static int[] RemoveMovesHM45(int[] moves)
+        {
+            var banned = GetFavorableHMBanlist(moves);
+
+            for (int i = 0; i < 4; i++)
+            {
+                if (banned.Contains(moves[i]))
+                    moves[i] = 0;
+            }
+
+            return moves;
+        }
+
+        /// <summary>
+        /// Transfer via advantageous game
+        /// </summary>
+        /// <param name="moves">Current moves</param>
+        /// <returns>Preferred move ban list</returns>
+        private static HashSet<int> GetFavorableHMBanlist(int[] moves)
+        {
+            // if has defog, return ban list with whirlpool
+            return moves.Contains(432) ? HM_HGSS : HM_DPPt;
+        }
     }
 }

PKHeX.Core/PKM/PK4.cs

@@ -381,16 +381,13 @@ namespace PKHeX.Core
                 pk5.AltForm = 0;
                 pk5.HeldItem = 0;
             }
-            else
+            else if(!Legal.HeldItems_BW.Contains((ushort)HeldItem))
             {
-                pk5.HeldItem = Legal.HeldItems_BW.Contains((ushort) HeldItem) ? HeldItem : 0;
+                pk5.HeldItem = 0; // if valid, it's already copied
             }
 
             // Fix PP
-            pk5.Move1_PP = pk5.GetMovePP(pk5.Move1, pk5.Move1_PPUps);
+            pk5.HealPP();
-            pk5.Move2_PP = pk5.GetMovePP(pk5.Move2, pk5.Move2_PPUps);
-            pk5.Move3_PP = pk5.GetMovePP(pk5.Move3, pk5.Move3_PPUps);
-            pk5.Move4_PP = pk5.GetMovePP(pk5.Move4, pk5.Move4_PPUps);
 
             // Disassociate Nature and PID, pk4 getter does PID%25
             pk5.Nature = Nature;
@@ -399,9 +396,7 @@ namespace PKHeX.Core
             BitConverter.GetBytes((uint)0).CopyTo(pk5.Data, 0x44);
 
             // Met / Crown Data Detection
-            pk5.Met_Location = pk5.Gen4 && pk5.FatefulEncounter && Legal.CrownBeasts.Contains(pk5.Species)
+            pk5.Met_Location = Legal.GetTransfer45MetLocation(pk5);
-                ? (pk5.Species == 251 ? Legal.Transfer4_CelebiUnused : Legal.Transfer4_CrownUnused) // Celebi : Beast
-                : Legal.Transfer4; // Pokétransfer (not Crown)
 
             // Egg Location is not modified; when clearing Pt/HGSS egg data, the location will revert to Faraway Place
             // pk5.Egg_Location = Egg_Location;
@@ -410,26 +405,15 @@ namespace PKHeX.Core
             BitConverter.GetBytes((ushort)0).CopyTo(pk5.Data, 0x86);
             pk5.Ball = Ball;
 
-            // Transfer Nickname and OT Name
+            // Transfer Nickname and OT Name, update encoding
             pk5.Nickname = Nickname;
             pk5.OT_Name = OT_Name;
 
             // Fix Level
-            pk5.Met_Level = Experience.GetLevel(pk5.EXP, pk5.Species, 0);
+            pk5.Met_Level = pk5.CurrentLevel;
 
             // Remove HM moves; Defog should be kept if both are learned.
-            int[] banned = Moves.Contains(250) && Moves.Contains(432) // Whirlpool & Defog
+            pk5.Moves = Legal.RemoveMovesHM45(pk5.Moves);
-                ? new[] {15, 19, 57, 70, 250, 249, 127, 431} // No Whirlpool
-                : new[] {15, 19, 57, 70,      249, 127, 431};// Transfer via advantageous game
-
-            int[] newMoves = pk5.Moves;
-            for (int i = 0; i < 4; i++)
-            {
-                if (banned.Contains(newMoves[i]))
-                    newMoves[i] = 0;
-            }
-
-            pk5.Moves = newMoves;
             pk5.FixMoves();
 
             pk5.RefreshChecksum();