Replace linq with similar but faster logic

PKHeX.Core/Legality/Encounters/Data/EncounterUtil.cs

@@ -1,5 +1,5 @@
-using System.Collections.Generic;
-using System.Linq;
+using System;
+using System.Collections.Generic;
 
 namespace PKHeX.Core
 {
@@ -14,31 +14,62 @@ internal static class EncounterUtil
         /// <param name="source">Table of valid encounters that appear for the game pairing</param>
         /// <param name="game">Game to filter for</param>
         /// <returns>Array of encounter objects that can be encountered in the input game</returns>
-        internal static T[] GetEncounters<T>(IEnumerable<T> source, GameVersion game) where T : IVersion
+        internal static T[] GetEncounters<T>(T[] source, GameVersion game) where T : EncounterStatic
         {
-            return source.Where(s => s.Version.Contains(game)).ToArray();
+            return Array.FindAll(source, s => s.Version.Contains(game));
         }
 
+        /// <summary>
+        /// Loads the language string lists into the <see cref="T"/> objects.
+        /// </summary>
+        /// <typeparam name="T">Encounter template type</typeparam>
+        /// <param name="table">Trade templates</param>
+        /// <param name="strings">Localization strings, grouped by language.</param>
+        /// <remarks>
+        /// The first half of strings in the language resource array are <see cref="EncounterTrade.Nicknames"/>
+        /// The second half of strings in the language resource strings are <see cref="EncounterTrade.TrainerNames"/>
+        /// </remarks>
         internal static void MarkEncounterTradeStrings<T>(T[] table, string[][] strings) where T : EncounterTrade
         {
-            int half = strings[1].Length / 2;
-            for (int i = 0; i < half; i++)
+            uint languageCount = (uint)strings[1].Length / 2;
+            for (uint i = 0; i < languageCount; i++)
             {
                 var t = table[i];
-                t.Nicknames = getNames(i, strings);
-                t.TrainerNames = getNames(i + half, strings);
+                t.Nicknames = GetNamesForLanguage(strings, i);
+                t.TrainerNames = GetNamesForLanguage(strings, languageCount + i);
             }
-            static string[] getNames(int i, IEnumerable<string[]> names) => names.Select(z => z.Length > i ? z[i] : string.Empty).ToArray();
         }
 
+        /// <summary>
+        /// Loads the language string lists into the <see cref="T"/> objects.
+        /// </summary>
+        /// <typeparam name="T">Encounter template type</typeparam>
+        /// <param name="table">Trade templates</param>
+        /// <param name="strings">Localization strings, grouped by language.</param>
         internal static void MarkEncounterTradeNicknames<T>(T[] table, string[][] strings) where T : EncounterTrade
         {
-            for (int i = 0; i < table.Length; i++)
+            for (uint i = 0; i < table.Length; i++)
             {
                 var t = table[i];
-                t.Nicknames = getNames(i, strings);
+                t.Nicknames = GetNamesForLanguage(strings, i);
             }
-            static string[] getNames(int i, IEnumerable<string[]> names) => names.Select(z => z.Length > i ? z[i] : string.Empty).ToArray();
+        }
+
+        /// <summary>
+        /// Grabs the localized names for individual templates for all languages from the specified <see cref="index"/> of the <see cref="names"/> list.
+        /// </summary>
+        /// <param name="names">Arrays of strings grouped by language</param>
+        /// <param name="index">Index to grab from the language arrays</param>
+        /// <returns>Row of localized strings for the template.</returns>
+        private static string[] GetNamesForLanguage(IReadOnlyList<string[]> names, uint index)
+        {
+            var result = new string[names.Count];
+            for (int i = 0; i < result.Length; i++)
+            {
+                var arr = names[i];
+                result[i] = index < arr.Length ? arr[index] : string.Empty;
+            }
+            return result;
         }
     }
 }