Handle gen4 egg nickname edge case

Egg is not saved as "EGG", it is "Egg". Nice job gf.
Instead of ignoring the nickname flag, detect if it should be used or
not.
Gen4 never uses it. Gen7 doesn't use it when it's a gift, but uses it
for daycare eggs (...).
Closes #1100

PKHeX/Legality/Checks.cs

@@ -312,9 +312,23 @@ private void verifyNickname()
         }
         private void verifyNicknameEgg()
         {
-            if (!pkm.IsNicknamed && (pkm.Format != 7))
-                AddLine(Severity.Invalid, V12, CheckIdentifier.Egg);
-            else if (PKX.getSpeciesNameGeneration(0, pkm.Language, pkm.GenNumber) != pkm.Nickname)
+            switch (pkm.Format)
+            {
+                case 4:
+                    if (pkm.IsNicknamed) // gen4 doesn't use the nickname flag for eggs
+                        AddLine(Severity.Invalid, V224, CheckIdentifier.Egg);
+                    break;
+                case 7:
+                    if (EncounterMatch is EncounterStatic ^ !pkm.IsNicknamed) // gen7 doesn't use for ingame gifts
+                        AddLine(Severity.Invalid, pkm.IsNicknamed ? V224 : V12, CheckIdentifier.Egg);
+                    break;
+                default:
+                    if (!pkm.IsNicknamed)
+                        AddLine(Severity.Invalid, V12, CheckIdentifier.Egg);
+                    break;
+            }
+
+            if (PKX.getSpeciesNameGeneration(0, pkm.Language, pkm.GenNumber) != pkm.Nickname)
                 AddLine(Severity.Invalid, V13, CheckIdentifier.Egg);
             else
                 AddLine(Severity.Valid, V14, CheckIdentifier.Egg);

PKHeX/Legality/LegalityCheckStrings.cs

@@ -114,7 +114,8 @@ public static class LegalityCheckStrings
         public static string V3 {get; set;} = "Species index invalid for Nickname comparison."; // Invalid
         public static string V20 {get; set;} = "Nickname does not match species name."; // Invalid
         public static string V13 {get; set;} = "Egg name does not match language Egg name."; // Invalid
-        public static string V12 {get; set;} = "Eggs must be nicknamed."; // Invalid
+        public static string V12 {get; set;} = "Egg must be nicknamed."; // Invalid
+        public static string V224 {get; set;} = "Egg must be not nicknamed."; // Invalid
         public static string V7 {get; set;} = "Ingame Trade invalid version?"; // Invalid
         public static string V8 {get; set;} = "Ingame Trade invalid index?"; // Invalid
         public static string V10 {get; set;} = "Ingame Trade OT has been altered."; // Invalid

PKHeX/PKM/PKX.cs

@@ -211,7 +211,7 @@ public static string getSpeciesNameGeneration(int species, int lang, int generat
         {
             string nick = getSpeciesName(species, lang);
 
-            if (generation < 5) // All caps GenIV and previous
+            if (generation < 5 && (generation != 4 || species != 0)) // All caps GenIV and previous, except GenIV eggs.
                 nick = nick.ToUpper();
             if (generation < 3)
                 nick = nick.Replace(" ", "");

PKHeX/Resources/text/en/LegalityCheckStrings_en.txt

@@ -75,7 +75,8 @@ V222 = Cannot be given this Nickname.
 V3 = Species index invalid for Nickname comparison.
 V20 = Nickname does not match species name.
 V13 = Egg name does not match language Egg name.
-V12 = Eggs must be nicknamed.
+V12 = Egg must be nicknamed.
+V224 = Egg must be not nicknamed.
 V7 = Ingame Trade invalid version?
 V8 = Ingame Trade invalid index?
 V10 = Ingame Trade OT has been altered.

PKHeX/Resources/text/ko/LegalityCheckStrings_ko.txt

@@ -77,6 +77,7 @@ V3 = 이름 비교에 사용할 포켓몬 종류 인덱스가 잘못되었습니
 V20 = 이름이 포켓몬 종류와 일치하지 않습니다.
 V13 = 알 이름이 언어별 알 이름과 일치하지 않습니다.
 V12 = 알은 반드시 이름 플래그가 켜져 있어야 합니다.
+V224 = Egg must be not nicknamed.
 V7 = 게임 내 교환의 버전이 잘못되었을 수 있습니다.
 V8 = 게임 내 교환의 인덱스가 잘못되었을 수 있습니다.
 V10 = 게임 내 교환의 어버이가 달라졌습니다.

PKHeX/Resources/text/zh/LegalityCheckStrings_zh.txt

@@ -77,6 +77,7 @@ V3 = 宝可梦种类无法用于昵称对比
 V20 = 昵称与种类名不一致。
 V13 = 蛋名称与语言不一致。
 V12 = 蛋必须有昵称。
+V224 = Egg must be not nicknamed.
 V7 = 游戏内连接交换版本不合法?
 V8 = 游戏内连接交换序号不合法?
 V10 = 游戏内连接交换的初训家被修改。