Added custom stat for trading with goblins

src/main/java/com/mrcrayfish/goblintraders/GoblinTraders.java

@@ -4,6 +4,7 @@
 import com.mrcrayfish.goblintraders.init.ModEntities;
 import com.mrcrayfish.goblintraders.init.ModItems;
 import com.mrcrayfish.goblintraders.init.ModSounds;
+import com.mrcrayfish.goblintraders.init.ModStats;
 import com.mrcrayfish.goblintraders.trades.TradeManager;
 import com.mrcrayfish.goblintraders.trades.type.BasicTrade;
 import net.minecraft.util.ResourceLocation;
@@ -37,6 +38,7 @@ private void onClientSetup(FMLClientSetupEvent event)
 
     private void onCommonSetup(FMLCommonSetupEvent event)
     {
+        ModStats.init();
         ModEntities.registerEntityTypeAttributes();
         TradeManager manager = TradeManager.instance();
         manager.registerTrader(ModEntities.GOBLIN_TRADER.get());

src/main/java/com/mrcrayfish/goblintraders/init/ModStats.java

@@ -0,0 +1,29 @@
+package com.mrcrayfish.goblintraders.init;
+
+import com.mrcrayfish.goblintraders.Reference;
+import net.minecraft.stats.IStatFormatter;
+import net.minecraft.stats.Stats;
+import net.minecraft.util.ResourceLocation;
+import net.minecraft.util.registry.Registry;
+
+/**
+ * Author: MrCrayfish
+ */
+public class ModStats
+{
+    public static final ResourceLocation TRADE_WITH_GOBLIN = registerCustom("trade_with_goblin", IStatFormatter.DEFAULT);
+
+    public static void init()
+    {
+        //Does nothing, just triggers java to load static fields
+    }
+
+    private static ResourceLocation registerCustom(String name, IStatFormatter formatter)
+    {
+        String key = Reference.MOD_ID + ":" + name;
+        ResourceLocation id = new ResourceLocation(key);
+        Registry.register(Registry.CUSTOM_STAT, key, id);
+        Stats.CUSTOM.get(id, formatter);
+        return id;
+    }
+}

src/main/java/com/mrcrayfish/goblintraders/mixin/MerchantResultSlotMixin.java

@@ -0,0 +1,33 @@
+package com.mrcrayfish.goblintraders.mixin;
+
+import com.mrcrayfish.goblintraders.entity.AbstractGoblinEntity;
+import com.mrcrayfish.goblintraders.init.ModStats;
+import net.minecraft.entity.merchant.IMerchant;
+import net.minecraft.inventory.container.MerchantResultSlot;
+import net.minecraft.util.ResourceLocation;
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.ModifyArg;
+
+/**
+ * Author: MrCrayfish
+ */
+@Mixin(MerchantResultSlot.class)
+public class MerchantResultSlotMixin
+{
+    @Shadow
+    @Final
+    private IMerchant merchant;
+
+    @ModifyArg(method = "onTake", at = @At(value = "INVOKE", target = "Lnet/minecraft/entity/player/PlayerEntity;addStat(Lnet/minecraft/util/ResourceLocation;)V"))
+    private ResourceLocation modifyAddStat(ResourceLocation stat)
+    {
+        if(this.merchant instanceof AbstractGoblinEntity)
+        {
+            return ModStats.TRADE_WITH_GOBLIN;
+        }
+        return stat;
+    }
+}

src/main/resources/assets/goblintraders/lang/en_us.json

@@ -4,5 +4,6 @@
     "subtitle.goblintraders.goblin_trader.annoyed_grunt": "Annoyed Grunt",
     "subtitle.goblintraders.goblin_trader.idle_grunt": "Idle Grunt",
     "item.goblintraders.goblin_trader_spawn_egg": "Goblin Trader Spawn Egg",
-    "item.goblintraders.vein_goblin_trader_spawn_egg": "Vein Goblin Trader Spawn Egg"
+    "item.goblintraders.vein_goblin_trader_spawn_egg": "Vein Goblin Trader Spawn Egg",
+    "stat.goblintraders.trade_with_goblin": "Traded with Goblins"
 }

src/main/resources/goblintraders.mixins.json

@@ -5,7 +5,8 @@
   "minVersion": "0.8",
   "refmap": "goblintraders.refmap.json",
   "mixins": [
-    "SpawnEggItemMixin"
+    "SpawnEggItemMixin",
+    "MerchantResultSlotMixin"
   ],
   "injectors": {
     "defaultRequire": 1