Eggs: explicitly pass generation instead of calculating

PKHeX.Core/Legality/Breeding.cs

@@ -91,12 +91,16 @@ namespace PKHeX.Core
         /// Checks if the <see cref="species"/> can be obtained from a daycare egg.
         /// </summary>
         /// <remarks>Chained with the other 2 overloads for incremental checks with different parameters.</remarks>
+        /// <param name="species">Current species</param>
         public static bool CanHatchAsEgg(int species) => !NoHatchFromEgg.Contains(species);
 
         /// <summary>
         /// Checks if the <see cref="species"/>-<see cref="form"/> can exist as a hatched egg in the requested <see cref="generation"/>.
         /// </summary>
         /// <remarks>Chained with the other 2 overloads for incremental checks with different parameters.</remarks>
+        /// <param name="species">Current species</param>
+        /// <param name="form">Current form</param>
+        /// <param name="generation">Generation of origin</param>
         public static bool CanHatchAsEgg(int species, int form, int generation)
         {
             if (form == 0)
@@ -116,6 +120,9 @@ namespace PKHeX.Core
         /// Checks if the <see cref="species"/>-<see cref="form"/> can exist as a hatched egg in the requested <see cref="game"/>.
         /// </summary>
         /// <remarks>Chained with the other 2 overloads for incremental checks with different parameters.</remarks>
+        /// <param name="species">Current species</param>
+        /// <param name="form">Current form</param>
+        /// <param name="game">Game of origin</param>
         public static bool CanHatchAsEgg(int species, int form, GameVersion game)
         {
             // Sanity check form for origin

PKHeX.Core/Legality/Encounters/Generator/ByGeneration/EncounterGenerator3.cs

@@ -187,7 +187,7 @@ namespace PKHeX.Core
 
             if (pkm.Version != (int)GameVersion.CXD) // no eggs in C/XD
             {
-                foreach (var z in GenerateEggs(pkm))
+                foreach (var z in GenerateEggs(pkm, 3))
                     yield return z;
             }
 

PKHeX.Core/Legality/Encounters/Generator/ByGeneration/EncounterGenerator4.cs

@@ -51,7 +51,7 @@ namespace PKHeX.Core
             }
             if (pkm.WasBredEgg)
             {
-                foreach (var z in GenerateEggs(pkm))
+                foreach (var z in GenerateEggs(pkm, 4))
                     yield return z;
             }
             foreach (var z in GetValidEncounterTrades(pkm, chain))

PKHeX.Core/Legality/Encounters/Generator/ByGeneration/EncounterGenerator5.cs

@@ -25,7 +25,7 @@ namespace PKHeX.Core
 
             if (pkm.WasBredEgg)
             {
-                foreach (var z in GenerateEggs(pkm))
+                foreach (var z in GenerateEggs(pkm, 5))
                 { yield return z; ++ctr; }
                 if (ctr == 0) yield break;
             }

PKHeX.Core/Legality/Encounters/Generator/ByGeneration/EncounterGenerator6.cs

@@ -48,7 +48,7 @@ namespace PKHeX.Core
 
             if (pkm.WasBredEgg)
             {
-                foreach (var z in GenerateEggs(pkm))
+                foreach (var z in GenerateEggs(pkm, 6))
                 { yield return z; ++ctr; }
                 if (ctr == 0) yield break;
             }

PKHeX.Core/Legality/Encounters/Generator/ByGeneration/EncounterGenerator7.cs

@@ -114,7 +114,7 @@ namespace PKHeX.Core
 
             if (pkm.WasBredEgg)
             {
-                foreach (var z in GenerateEggs(pkm))
+                foreach (var z in GenerateEggs(pkm, 7))
                 { yield return z; ++ctr; }
                 if (ctr == 0) yield break;
             }

PKHeX.Core/Legality/Encounters/Generator/ByGeneration/EncounterGenerator8.cs

@@ -33,7 +33,7 @@ namespace PKHeX.Core
 
             if (pkm.WasBredEgg)
             {
-                foreach (var z in GenerateEggs(pkm))
+                foreach (var z in GenerateEggs(pkm, 8))
                 { yield return z; ++ctr; }
                 if (ctr == 0) yield break;
             }

PKHeX.Core/Legality/Encounters/Generator/Moveset/EncounterMovesetGenerator.cs

@@ -230,7 +230,7 @@ namespace PKHeX.Core
                 yield break;
             var eggs = gen == 2
                 ? EncounterEggGenerator2.GenerateEggs(pk, chain, all: true)
-                : EncounterEggGenerator.GenerateEggs(pk, chain, all: true);
+                : EncounterEggGenerator.GenerateEggs(pk, chain, gen, all: true);
             foreach (var egg in eggs)
             {
                 if (needs.Count == 0)

PKHeX.Core/Legality/Encounters/Generator/Specific/EncounterEggGenerator.cs

@@ -1,5 +1,4 @@
-using System;
+using System.Collections.Generic;
-using System.Collections.Generic;
 
 using static PKHeX.Core.Legal;
 
@@ -7,23 +6,20 @@ namespace PKHeX.Core
 {
     public static class EncounterEggGenerator
     {
-        public static IEnumerable<EncounterEgg> GenerateEggs(PKM pkm, bool all = false)
+        public static IEnumerable<EncounterEgg> GenerateEggs(PKM pkm, int generation, bool all = false)
         {
-            var table = EvolutionTree.GetEvolutionTree(pkm, Math.Max(2, pkm.Format));
+            var table = EvolutionTree.GetEvolutionTree(pkm, pkm.Format);
-            int maxSpeciesOrigin = GetMaxSpeciesOrigin(pkm.Generation);
+            int maxSpeciesOrigin = GetMaxSpeciesOrigin(generation);
             var evos = table.GetValidPreEvolutions(pkm, maxLevel: 100, maxSpeciesOrigin: maxSpeciesOrigin, skipChecks: true);
-            return GenerateEggs(pkm, evos, all);
+            return GenerateEggs(pkm, evos, generation, all);
         }
 
-        public static IEnumerable<EncounterEgg> GenerateEggs(PKM pkm, IReadOnlyList<EvoCriteria> chain, bool all = false)
+        public static IEnumerable<EncounterEgg> GenerateEggs(PKM pkm, IReadOnlyList<EvoCriteria> chain, int generation, bool all = false)
         {
+            System.Diagnostics.Debug.Assert(generation >= 3); // if generating Gen2 eggs, use the other generator.
             int species = pkm.Species;
             if (!Breeding.CanHatchAsEgg(species))
                 yield break;
-
-            int generation = pkm.Generation;
-            if (generation <= 2)
-                yield break; // can't get eggs; if generating Gen2 eggs, use the other generator.
             if (!Breeding.CanHatchAsEgg(species, pkm.Form, generation))
                 yield break; // can't originate from eggs
 

PKHeX.Core/Legality/MoveListSuggest.cs

@@ -108,7 +108,7 @@ namespace PKHeX.Core
         /// Gets the current <see cref="PKM.RelearnMoves"/> array of four moves that might be legal.
         /// </summary>
         /// <remarks>Use <see cref="GetSuggestedRelearnMovesFromEncounter"/> instead of calling directly; this method just puts default values in without considering the final moveset.</remarks>
-        public static IReadOnlyList<int> GetSuggestedRelearn(this IEncounterable enc, PKM pkm)
+        public static IReadOnlyList<int> GetSuggestedRelearn(this IEncounterTemplate enc, PKM pkm)
         {
             if (VerifyRelearnMoves.ShouldNotHaveRelearnMoves(enc, pkm))
                 return Empty;
@@ -148,7 +148,8 @@ namespace PKHeX.Core
             // Split-breed species like Budew & Roselia may be legal for one, and not the other.
             // If we're not a split-breed or are already legal, return.
             var result = enc.GetEggRelearnMoves(parse, pkm);
-            var split = Breeding.GetSplitBreedGeneration(enc.Generation);
+            int generation = enc.Generation;
+            var split = Breeding.GetSplitBreedGeneration(generation);
             if (!split.Contains(enc.Species) || enc.Generation <= 2)
                 return result;
 
@@ -159,7 +160,7 @@ namespace PKHeX.Core
                 return result;
 
             // Try again with the other split-breed species if possible.
-            var incense = EncounterEggGenerator.GenerateEggs(tmp).FirstOrDefault();
+            var incense = EncounterEggGenerator.GenerateEggs(tmp, generation).FirstOrDefault();
             if (incense is null || incense.Species == enc.Species)
                 return result;