Return evolution chains with more accurate min-max

Closes #3371 ty @Ninjistix !

PKHeX.Core/Legality/Encounters/Verifiers/VerifyCurrentMoves.cs

@@ -140,7 +140,7 @@ namespace PKHeX.Core
         {
             var res = new CheckMoveResult[4];
             var enc = info.EncounterMatch;
-            var level = pkm.HasOriginalMetLocation ? pkm.Met_Level : enc.LevelMin;
+            var level = info.EvoChainsAllGens[enc.Generation][^1].MinLevel;
             var InitialMoves = Array.Empty<int>();
             var SpecialMoves = GetSpecialMoves(enc);
             var games = enc.Generation == 1 ? GBRestrictions.GetGen1Versions(enc) : GBRestrictions.GetGen2Versions(enc, pkm.Korean);

PKHeX.Core/Legality/Evolutions/EvolutionChain.cs

@@ -165,14 +165,14 @@ namespace PKHeX.Core
 
         private static List<EvoCriteria> GetEvolutionChain(PKM pkm, IEncounterTemplate enc, int mostEvolvedSpecies, int maxlevel)
         {
-            var chain = GetValidPreEvolutions(pkm, minLevel: enc.LevelMin);
+            var min = enc.LevelMin;
+            if (pkm.HasOriginalMetLocation && pkm.Met_Level != 0)
+                min = pkm.Met_Level;
+            var chain = GetValidPreEvolutions(pkm, minLevel: min);
             if (enc.Species == mostEvolvedSpecies)
             {
                 if (chain.Count != 1)
-                {
                     chain.RemoveAll(z => z.Species != enc.Species);
-                    chain[0].MinLevel = enc.LevelMin;
-                }
                 return chain;
             }
 

PKHeX.Core/Legality/Evolutions/EvolutionTree.cs

@@ -216,7 +216,7 @@ namespace PKHeX.Core
             {
                 return new List<EvoCriteria>(2)
                 {
-                    new((int)Species.Shedinja, 0) { Level = maxLevel, MinLevel = 20 },
+                    new((int)Species.Shedinja, 0) { Level = maxLevel, MinLevel = Math.Max(minLevel, 20) },
                     new((int)Species.Nincada, 0) { Level = maxLevel, MinLevel = minLevel },
                 };
             }
@@ -360,14 +360,14 @@ namespace PKHeX.Core
                         break; // impossible evolution
 
                     oneValid = true;
-                    UpdateMinValues(dl, evo);
-                    if (evo.RequiresLevelUp)
-                        lvl--;
+                    UpdateMinValues(dl, evo, minLevel);
 
                     species = link.Species;
                     form = link.Form;
                     var detail = evo.GetEvoCriteria(species, form, lvl);
                     dl.Add(detail);
+                    if (evo.RequiresLevelUp)
+                        lvl--;
                     break;
                 }
                 if (!oneValid)
@@ -379,30 +379,39 @@ namespace PKHeX.Core
             if (last.Species > maxSpeciesOrigin && dl.Any(d => d.Species <= maxSpeciesOrigin))
                 dl.RemoveAt(dl.Count - 1);
 
-            // Last species is the wild/hatched species, the minimum level is 1 because it has not evolved from previous species
+            // Last species is the wild/hatched species, the minimum level is because it has not evolved from previous species
             last = dl[^1];
-            last.MinLevel = 1;
+            last.MinLevel = minLevel;
             last.RequiresLvlUp = false;
+
+            // Rectify minimum levels
+            for (int i = dl.Count - 2; i >= 0; i--)
+            {
+                var evo = dl[i];
+                var prev = dl[i + 1];
+                evo.MinLevel = Math.Max(prev.MinLevel + (evo.RequiresLvlUp ? 1 : 0), evo.MinLevel);
+            }
+
             return dl;
         }
 
-        private static void UpdateMinValues(IReadOnlyList<EvoCriteria> dl, EvolutionMethod evo)
+        private static void UpdateMinValues(IReadOnlyList<EvoCriteria> dl, EvolutionMethod evo, int minLevel)
         {
             var last = dl[^1];
             if (!evo.RequiresLevelUp)
             {
                 // Evolutions like elemental stones, trade, etc
-                last.MinLevel = 1;
+                last.MinLevel = minLevel;
                 return;
             }
             if (evo.Level == 0)
             {
-                // Friendship based Evolutions, Pichu -> Pikachu, Eevee -> Umbreon, etc
-                last.MinLevel = 2;
+                // Friendship based Level Up Evolutions, Pichu -> Pikachu, Eevee -> Umbreon, etc
+                last.MinLevel = minLevel + 1;
 
                 var first = dl[0];
                 if (dl.Count > 1 && !first.RequiresLvlUp)
-                    first.MinLevel = 2; // Raichu from Pikachu would have a minimum level of 1; accounting for Pichu (level up required) results in a minimum level of 2
+                    first.MinLevel = minLevel + 1; // Raichu from Pikachu would have a minimum level of 1; accounting for Pichu (level up required) results in a minimum level of 2
             }
             else // level up evolutions
             {

PKHeX.Core/Legality/MoveList.cs

@@ -162,10 +162,11 @@ namespace PKHeX.Core
             var min = pkm is IBattleVersion b ? Math.Max(0, b.GetMinGeneration()) : 1;
             for (int i = min; i < evoChains.Length; i++)
             {
-                if (evoChains[i].Count == 0)
+                var evos = evoChains[i];
+                if (evos.Count == 0)
                     continue;
 
-                result[i] = GetValidMoves(pkm, evoChains[i], i, types, RemoveTransferHM).ToList();
+                result[i] = GetValidMoves(pkm, evos, i, types, RemoveTransferHM).ToList();
             }
             return result;
         }
@@ -225,22 +226,21 @@ namespace PKHeX.Core
             for (var i = 0; i < chain.Count; i++)
             {
                 var evo = chain[i];
+                bool encounteredEvo = i == chain.Count - 1;
+
                 if (generation <= 2)
                 {
-                    bool encounteredEvo = i == chain.Count - 1;
                     if (encounteredEvo) // minimum level, otherwise next learnable level
-                        minLvLG1 = (pkm.HasOriginalMetLocation ? pkm.Met_Level : evo.MinLevel) + 1;
-                    else if (evo.RequiresLvlUp) // learns level up moves immediately after evolving
-                        minLvLG1 = evo.MinLevel;
-                    else
                         minLvLG1 = evo.MinLevel + 1;
+                    else // learns level up moves immediately after evolving
+                        minLvLG1 = evo.MinLevel;
 
                     if (!ParseSettings.AllowGen2MoveReminder(pkm))
                         minLvLG2 = minLvLG1;
                 }
 
                 var maxLevel = evo.Level;
-                if (i != 0 && chain[i - 1].RequiresLvlUp) // evolution
+                if (!encounteredEvo) // evolution
                     ++maxLevel; // allow lvlmoves from the level it evolved to the next species
                 var moves = GetMoves(pkm, evo.Species, evo.Form, maxLevel, minLvLG1, minLvLG2, version, types, RemoveTransferHM, generation);
                 r.AddRange(moves);