Centralized Faction Goodwill Penalties in a single Helper

Source/Common/Helpers/FactionUtility.cs

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+using RimWorld;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Verse;
+
+namespace RJW_Genes
+{
+    public class FactionUtility
+    {
+
+        /// <summary>
+        /// Tries to change the goodwill between the factions of two pawns. 
+        /// Exceptions when nothing happens:
+        /// - Pawns, or Pawns Factions, are null 
+        /// - The `actors` Faction is not the players faction
+        /// - Both pawns have the same faction
+        /// - The Event is not found
+        /// </summary>
+        /// <param name="actor">The pawn that initiated a faction-goodwill change by his actions</param>
+        /// <param name="target">The pawn that was harmed/affected by the action</param>
+        /// <param name="HistoryEventDefname">The event defname, for proper reporting</param>
+        /// <param name="goodWillChange">How much (positive or negative) the goodwill will change</param>
+        public static void HandleFactionGoodWillPenalties(Pawn actor, Pawn target, string HistoryEventDefname, int goodWillChange, bool canSendHostileLetter=true)
+        {
+            if (actor == null) return;
+            if (target == null) return;
+            if (
+                target.Faction != null && actor.Faction != null
+                && target.Faction != actor.Faction
+                && target.Faction != Faction.OfPlayer)
+            {
+                HistoryEventDef reason = DefDatabase<HistoryEventDef>.GetNamedSilentFail(HistoryEventDefname);
+                if (reason == null) return;
+
+                target.Faction.TryAffectGoodwillWith(actor.Faction, goodWillChange, true, canSendHostileLetter, reason, target);
+            }
+        }
+    }
+}