papermc/Spigot-Server-Patches/0111-LootTable-API-Replenishable-Lootables-Feature.patch

From fd6c2c49c3fa2bbf29d1ea1ec2c04d901a1060d6 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sun, 1 May 2016 21:19:14 -0400
Subject: [PATCH] LootTable API & Replenishable Lootables Feature

Provides an API to control the loot table for an object.
Also provides a feature that any Lootable Inventory (Chests in Structures)
can automatically replenish after a given time.

This feature is good for long term worlds so that newer players
do not suffer with "Every chest has been looted"

diff --git a/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
index 8d54af6bb7..a3823408ca 100644
--- a/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
+++ b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
@@ -254,4 +254,26 @@ public class PaperWorldConfig {
         this.frostedIceDelayMax = this.getInt("frosted-ice.delay.max", this.frostedIceDelayMax);
         log("Frosted Ice: " + (this.frostedIceEnabled ? "enabled" : "disabled") + " / delay: min=" + this.frostedIceDelayMin + ", max=" + this.frostedIceDelayMax);
     }
+
+    public boolean autoReplenishLootables;
+    public boolean restrictPlayerReloot;
+    public boolean changeLootTableSeedOnFill;
+    public int maxLootableRefills;
+    public int lootableRegenMin;
+    public int lootableRegenMax;
+    private void enhancedLootables() {
+        autoReplenishLootables = getBoolean("lootables.auto-replenish", false);
+        restrictPlayerReloot = getBoolean("lootables.restrict-player-reloot", true);
+        changeLootTableSeedOnFill = getBoolean("lootables.reset-seed-on-fill", true);
+        maxLootableRefills = getInt("lootables.max-refills", -1);
+        lootableRegenMin = PaperConfig.getSeconds(getString("lootables.refresh-min", "12h"));
+        lootableRegenMax = PaperConfig.getSeconds(getString("lootables.refresh-max", "2d"));
+        if (autoReplenishLootables) {
+            log("Lootables: Replenishing every " +
+                PaperConfig.timeSummary(lootableRegenMin) + " to " +
+                PaperConfig.timeSummary(lootableRegenMax) +
+                (restrictPlayerReloot ? " (restricting reloot)" : "")
+            );
+        }
+    }
 }
diff --git a/src/main/java/com/destroystokyo/paper/loottable/CraftLootable.java b/src/main/java/com/destroystokyo/paper/loottable/CraftLootable.java
new file mode 100644
index 0000000000..36c36d158f
--- /dev/null
+++ b/src/main/java/com/destroystokyo/paper/loottable/CraftLootable.java
@@ -0,0 +1,12 @@
+package com.destroystokyo.paper.loottable;
+
+import net.minecraft.server.World;
+
+interface CraftLootable extends Lootable {
+
+    World getNMSWorld();
+
+    default org.bukkit.World getBukkitWorld() {
+        return getNMSWorld().getWorld();
+    }
+}
diff --git a/src/main/java/com/destroystokyo/paper/loottable/CraftLootableBlockInventory.java b/src/main/java/com/destroystokyo/paper/loottable/CraftLootableBlockInventory.java
new file mode 100644
index 0000000000..20d236c451
--- /dev/null
+++ b/src/main/java/com/destroystokyo/paper/loottable/CraftLootableBlockInventory.java
@@ -0,0 +1,33 @@
+package com.destroystokyo.paper.loottable;
+
+import net.minecraft.server.BlockPosition;
+import net.minecraft.server.TileEntityLootable;
+import net.minecraft.server.World;
+import org.bukkit.Chunk;
+import org.bukkit.block.Block;
+
+public interface CraftLootableBlockInventory extends LootableBlockInventory, CraftLootableInventory {
+
+    TileEntityLootable getTileEntity();
+
+    @Override
+    default LootableInventory getAPILootableInventory() {
+        return this;
+    }
+
+    @Override
+    default World getNMSWorld() {
+        return getTileEntity().getWorld();
+    }
+
+    default Block getBlock() {
+        final BlockPosition position = getTileEntity().getPosition();
+        final Chunk bukkitChunk = getTileEntity().getWorld().getChunkAtWorldCoords(position).bukkitChunk;
+        return bukkitChunk.getBlock(position.getX(), position.getY(), position.getZ());
+    }
+
+    @Override
+    default CraftLootableInventoryData getLootableData() {
+        return getTileEntity().getLootableData();
+    }
+}
diff --git a/src/main/java/com/destroystokyo/paper/loottable/CraftLootableEntityInventory.java b/src/main/java/com/destroystokyo/paper/loottable/CraftLootableEntityInventory.java
new file mode 100644
index 0000000000..1150dee01e
--- /dev/null
+++ b/src/main/java/com/destroystokyo/paper/loottable/CraftLootableEntityInventory.java
@@ -0,0 +1,31 @@
+package com.destroystokyo.paper.loottable;
+
+import net.minecraft.server.World;
+import org.bukkit.entity.Entity;
+
+public interface CraftLootableEntityInventory extends LootableEntityInventory, CraftLootableInventory {
+
+    net.minecraft.server.Entity getHandle();
+
+    @Override
+    default LootableInventory getAPILootableInventory() {
+        return this;
+    }
+
+    default Entity getEntity() {
+        return getHandle().getBukkitEntity();
+    }
+
+    @Override
+    default World getNMSWorld() {
+        return getHandle().getWorld();
+    }
+
+    @Override
+    default CraftLootableInventoryData getLootableData() {
+        if (getHandle() instanceof CraftLootableInventory) {
+            return ((CraftLootableInventory) getHandle()).getLootableData();
+        }
+        return null;
+    }
+}
diff --git a/src/main/java/com/destroystokyo/paper/loottable/CraftLootableInventory.java b/src/main/java/com/destroystokyo/paper/loottable/CraftLootableInventory.java
new file mode 100644
index 0000000000..b72232093b
--- /dev/null
+++ b/src/main/java/com/destroystokyo/paper/loottable/CraftLootableInventory.java
@@ -0,0 +1,62 @@
+package com.destroystokyo.paper.loottable;
+
+import java.util.UUID;
+
+public interface CraftLootableInventory extends CraftLootable, LootableInventory {
+
+    CraftLootableInventoryData getLootableData();
+    LootableInventory getAPILootableInventory();
+
+    @Override
+    default boolean isRefillEnabled() {
+        return getNMSWorld().paperConfig.autoReplenishLootables;
+    }
+
+    @Override
+    default boolean hasBeenFilled() {
+        return getLastFilled() != -1;
+    }
+
+    @Override
+    default boolean hasPlayerLooted(UUID player) {
+        return getLootableData().hasPlayerLooted(player);
+    }
+
+    @Override
+    default Long getLastLooted(UUID player) {
+        return getLootableData().getLastLooted(player);
+    }
+
+    @Override
+    default boolean setHasPlayerLooted(UUID player, boolean looted) {
+        final boolean hasLooted = hasPlayerLooted(player);
+        if (hasLooted != looted) {
+            getLootableData().setPlayerLootedState(player, looted);
+        }
+        return hasLooted;
+    }
+
+    @Override
+    default boolean hasPendingRefill() {
+        long nextRefill = getLootableData().getNextRefill();
+        return nextRefill != -1 && nextRefill > getLootableData().getLastFill();
+    }
+
+    @Override
+    default long getLastFilled() {
+        return getLootableData().getLastFill();
+    }
+
+    @Override
+    default long getNextRefill() {
+        return getLootableData().getNextRefill();
+    }
+
+    @Override
+    default long setNextRefill(long refillAt) {
+        if (refillAt < -1) {
+            refillAt = -1;
+        }
+        return getLootableData().setNextRefill(refillAt);
+    }
+}
diff --git a/src/main/java/com/destroystokyo/paper/loottable/CraftLootableInventoryData.java b/src/main/java/com/destroystokyo/paper/loottable/CraftLootableInventoryData.java
new file mode 100644
index 0000000000..8547205456
--- /dev/null
+++ b/src/main/java/com/destroystokyo/paper/loottable/CraftLootableInventoryData.java
@@ -0,0 +1,179 @@
+package com.destroystokyo.paper.loottable;
+
+import com.destroystokyo.paper.PaperWorldConfig;
+import net.minecraft.server.*;
+import org.bukkit.entity.Player;
+import org.bukkit.loot.LootTable;
+
+import javax.annotation.Nullable;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Random;
+import java.util.UUID;
+
+public class CraftLootableInventoryData {
+
+    private static final Random RANDOM = new Random();
+
+    private long lastFill = -1;
+    private long nextRefill = -1;
+    private int numRefills = 0;
+    private Map<UUID, Long> lootedPlayers;
+    private final CraftLootableInventory lootable;
+
+    public CraftLootableInventoryData(CraftLootableInventory lootable) {
+        this.lootable = lootable;
+    }
+
+    long getLastFill() {
+        return this.lastFill;
+    }
+
+    long getNextRefill() {
+        return this.nextRefill;
+    }
+
+    long setNextRefill(long nextRefill) {
+        long prev = this.nextRefill;
+        this.nextRefill = nextRefill;
+        return prev;
+    }
+
+    public boolean shouldReplenish(@Nullable EntityHuman player) {
+        LootTable table = this.lootable.getLootTable();
+
+        // No Loot Table associated
+        if (table == null) {
+            return false;
+        }
+
+        // ALWAYS process the first fill
+        if (this.lastFill == -1) {
+            return true;
+        }
+
+        // Only process refills when a player is set
+        if (player == null) {
+            return false;
+        }
+
+        // Chest is not scheduled for refill
+        if (this.nextRefill == -1) {
+            return false;
+        }
+
+        final PaperWorldConfig paperConfig = this.lootable.getNMSWorld().paperConfig;
+
+        // Check if max refills has been hit
+        if (paperConfig.maxLootableRefills != -1 && this.numRefills >= paperConfig.maxLootableRefills) {
+            return false;
+        }
+
+        // Refill has not been reached
+        if (this.nextRefill > System.currentTimeMillis()) {
+            return false;
+        }
+
+
+        final Player bukkitPlayer = (Player) player.getBukkitEntity();
+        LootableInventoryReplenishEvent event = new LootableInventoryReplenishEvent(bukkitPlayer, lootable.getAPILootableInventory());
+        if (paperConfig.restrictPlayerReloot && hasPlayerLooted(player.getUniqueID())) {
+            event.setCancelled(true);
+        }
+        return event.callEvent();
+    }
+    public void processRefill(@Nullable EntityHuman player) {
+        this.lastFill = System.currentTimeMillis();
+        final PaperWorldConfig paperConfig = this.lootable.getNMSWorld().paperConfig;
+        if (paperConfig.autoReplenishLootables) {
+            int min = paperConfig.lootableRegenMin;
+            int max = paperConfig.lootableRegenMax;
+            this.nextRefill = this.lastFill + (min + RANDOM.nextInt(max - min + 1)) * 1000L;
+            this.numRefills++;
+            if (paperConfig.changeLootTableSeedOnFill) {
+                this.lootable.setLootTableSeed(0);
+            }
+            if (player != null) { // This means that numRefills can be incremented without a player being in the lootedPlayers list - Seems to be EntityMinecartChest specific
+                this.setPlayerLootedState(player.getUniqueID(), true);
+            }
+        } else {
+            this.lootable.clearLootTable();
+        }
+    }
+
+
+    public void loadNbt(NBTTagCompound base) {
+        if (!base.hasKeyOfType("Paper.LootableData", 10)) { // 10 = compound
+            return;
+        }
+        NBTTagCompound comp = base.getCompound("Paper.LootableData");
+        if (comp.hasKey("lastFill")) {
+            this.lastFill = comp.getLong("lastFill");
+        }
+        if (comp.hasKey("nextRefill")) {
+            this.nextRefill = comp.getLong("nextRefill");
+        }
+
+        if (comp.hasKey("numRefills")) {
+            this.numRefills = comp.getInt("numRefills");
+        }
+        if (comp.hasKeyOfType("lootedPlayers", 9)) { // 9 = list
+            NBTTagList list = comp.getList("lootedPlayers", 10); // 10 = compound
+            final int size = list.size();
+            if (size > 0) {
+                this.lootedPlayers = new HashMap<>(list.size());
+            }
+            for (int i = 0; i < size; i++) {
+                final NBTTagCompound cmp = list.getCompound(i);
+                lootedPlayers.put(cmp.getUUID("UUID"), cmp.getLong("Time"));
+            }
+        }
+    }
+    public void saveNbt(NBTTagCompound base) {
+        NBTTagCompound comp = new NBTTagCompound();
+        if (this.nextRefill != -1) {
+            comp.setLong("nextRefill", this.nextRefill);
+        }
+        if (this.lastFill != -1) {
+            comp.setLong("lastFill", this.lastFill);
+        }
+        if (this.numRefills != 0) {
+            comp.setInt("numRefills", this.numRefills);
+        }
+        if (this.lootedPlayers != null && !this.lootedPlayers.isEmpty()) {
+            NBTTagList list = new NBTTagList();
+            for (Map.Entry<UUID, Long> entry : this.lootedPlayers.entrySet()) {
+                NBTTagCompound cmp = new NBTTagCompound();
+                cmp.setUUID("UUID", entry.getKey());
+                cmp.setLong("Time", entry.getValue());
+                list.add(cmp);
+            }
+            comp.set("lootedPlayers", list);
+        }
+
+        if (!comp.isEmpty()) {
+            base.set("Paper.LootableData", comp);
+        }
+    }
+
+    void setPlayerLootedState(UUID player, boolean looted) {
+        if (looted && this.lootedPlayers == null) {
+            this.lootedPlayers = new HashMap<>();
+        }
+        if (looted) {
+            if (!this.lootedPlayers.containsKey(player)) {
+                this.lootedPlayers.put(player, System.currentTimeMillis());
+            }
+        } else if (this.lootedPlayers != null) {
+            this.lootedPlayers.remove(player);
+        }
+    }
+
+    boolean hasPlayerLooted(UUID player) {
+        return this.lootedPlayers != null && this.lootedPlayers.containsKey(player);
+    }
+
+    Long getLastLooted(UUID player) {
+        return lootedPlayers != null ? lootedPlayers.get(player) : null;
+    }
+}
diff --git a/src/main/java/net/minecraft/server/EntityMinecartContainer.java b/src/main/java/net/minecraft/server/EntityMinecartContainer.java
index 91b38fd64b..7120f00b6a 100644
--- a/src/main/java/net/minecraft/server/EntityMinecartContainer.java
+++ b/src/main/java/net/minecraft/server/EntityMinecartContainer.java
@@ -5,18 +5,25 @@ import java.util.Random;
 import javax.annotation.Nullable;
 // CraftBukkit start
 import java.util.List;
+// Paper start
+import com.destroystokyo.paper.loottable.CraftLootableInventoryData;
+import com.destroystokyo.paper.loottable.CraftLootableInventory;
+import com.destroystokyo.paper.loottable.LootableInventory;
+import org.bukkit.Bukkit;
+import org.bukkit.craftbukkit.util.CraftNamespacedKey;
+// Paper end
 import org.bukkit.Location;
 import org.bukkit.craftbukkit.entity.CraftHumanEntity;
 import org.bukkit.entity.HumanEntity;
 import org.bukkit.inventory.InventoryHolder;
 // CraftBukkit end
 
-public abstract class EntityMinecartContainer extends EntityMinecartAbstract implements ITileInventory, ILootable {
+public abstract class EntityMinecartContainer extends EntityMinecartAbstract implements ITileInventory, ILootable, CraftLootableInventory { // Paper
 
     private NonNullList<ItemStack> items;
     private boolean b;
-    private MinecraftKey c;
-    public long d; // CraftBukkit private -> public
+    private MinecraftKey c; private MinecraftKey getLootTableKey() { return c; } private void setLootTable(MinecraftKey key) { c = key; } // Paper - OBFHELPER
+    public long d; public long getSeed() { return d; } public void setSeed(long seed) { d = seed; } // Paper - OBFHELPER // CraftBukkit private -> public
 
     // CraftBukkit start
     public List<HumanEntity> transaction = new java.util.ArrayList<HumanEntity>();
@@ -168,12 +175,13 @@ public abstract class EntityMinecartContainer extends EntityMinecartAbstract imp
 
     protected void b(NBTTagCompound nbttagcompound) {
         super.b(nbttagcompound);
+        lootableData.saveNbt(nbttagcompound); // Paper
         if (this.c != null) {
             nbttagcompound.setString("LootTable", this.c.toString());
             if (this.d != 0L) {
                 nbttagcompound.setLong("LootTableSeed", this.d);
             }
-        } else {
+        } if (true) { // Paper - Always save the items, Table may stick around
             ContainerUtil.a(nbttagcompound, this.items);
         }
 
@@ -181,11 +189,12 @@ public abstract class EntityMinecartContainer extends EntityMinecartAbstract imp
 
     protected void a(NBTTagCompound nbttagcompound) {
         super.a(nbttagcompound);
+        lootableData.loadNbt(nbttagcompound); // Paper
         this.items = NonNullList.a(this.getSize(), ItemStack.a);
         if (nbttagcompound.hasKeyOfType("LootTable", 8)) {
             this.c = new MinecraftKey(nbttagcompound.getString("LootTable"));
             this.d = nbttagcompound.getLong("LootTableSeed");
-        } else {
+        } if (true) { // Paper - always load the items, table may still remain
             ContainerUtil.b(nbttagcompound, this.items);
         }
 
@@ -234,10 +243,10 @@ public abstract class EntityMinecartContainer extends EntityMinecartAbstract imp
     }
 
     public void f(@Nullable EntityHuman entityhuman) {
-        if (this.c != null && this.world.getMinecraftServer() != null) {
+        if (lootableData.shouldReplenish(entityhuman) && this.world.getMinecraftServer() != null) { // Paper
             LootTable loottable = this.world.getMinecraftServer().aP().a(this.c);
 
-            this.c = null;
+            lootableData.processRefill(entityhuman); // Paper
             Random random;
 
             if (this.d == 0L) {
@@ -270,4 +279,39 @@ public abstract class EntityMinecartContainer extends EntityMinecartAbstract imp
     public MinecraftKey Q_() {
         return this.c;
     }
+
+    // Paper start
+    @Override
+    public org.bukkit.loot.LootTable getLootTable() {
+        return getLootTableKey() != null ? Bukkit.getLootTable(CraftNamespacedKey.fromMinecraft(getLootTableKey())) : null;
+    }
+
+    @Override
+    public void setLootTable(org.bukkit.loot.LootTable table, long seed) {
+        setLootTable(table);
+        setSeed(seed);
+    }
+
+    @Override
+    public void setLootTable(org.bukkit.loot.LootTable table) {
+        MinecraftKey newKey = (table == null) ? null : CraftNamespacedKey.toMinecraft(table.getKey());
+        setLootTable(newKey);
+    }
+    private final CraftLootableInventoryData lootableData = new CraftLootableInventoryData(this);
+
+    @Override
+    public CraftLootableInventoryData getLootableData() {
+        return lootableData;
+    }
+
+    @Override
+    public LootableInventory getAPILootableInventory() {
+        return (LootableInventory) this.getBukkitEntity();
+    }
+
+    @Override
+    public World getNMSWorld() {
+        return this.world;
+    }
+    // Paper end
 }
diff --git a/src/main/java/net/minecraft/server/TileEntityLootable.java b/src/main/java/net/minecraft/server/TileEntityLootable.java
index fbda02b321..e0f87a3533 100644
--- a/src/main/java/net/minecraft/server/TileEntityLootable.java
+++ b/src/main/java/net/minecraft/server/TileEntityLootable.java
@@ -1,12 +1,20 @@
 package net.minecraft.server;
 
+// Paper start
+import com.destroystokyo.paper.loottable.CraftLootableInventoryData;
+import com.destroystokyo.paper.loottable.CraftLootableInventory;
+import com.destroystokyo.paper.loottable.LootableInventory;
+import org.bukkit.Bukkit;
+import org.bukkit.craftbukkit.util.CraftNamespacedKey;
+// Paper end
+
 import java.util.Random;
 import javax.annotation.Nullable;
 
-public abstract class TileEntityLootable extends TileEntityContainer implements ILootable {
+public abstract class TileEntityLootable extends TileEntityContainer implements ILootable, CraftLootableInventory { // Paper
 
-    protected MinecraftKey g;
-    protected long h;
+    protected MinecraftKey g; private MinecraftKey getLootTableKey() { return g; } private void setLootTable(MinecraftKey key) { g = key; } // Paper - OBFHELPER
+    protected long h; public long getSeed() { return h; } public void setSeed(long seed) { h = seed; } // Paper - OBFHELPER
     protected IChatBaseComponent i;
 
     protected TileEntityLootable(TileEntityTypes<?> tileentitytypes) {
@@ -23,16 +31,18 @@ public abstract class TileEntityLootable extends TileEntityContainer implements
     }
 
     protected boolean d(NBTTagCompound nbttagcompound) {
+        lootableData.loadNbt(nbttagcompound); // Paper
         if (nbttagcompound.hasKeyOfType("LootTable", 8)) {
             this.g = new MinecraftKey(nbttagcompound.getString("LootTable"));
             this.h = nbttagcompound.getLong("LootTableSeed");
-            return true;
+            return false; // Paper - always load the items, table may still remain
         } else {
             return false;
         }
     }
 
     protected boolean e(NBTTagCompound nbttagcompound) {
+        lootableData.saveNbt(nbttagcompound); // Paper
         if (this.g == null) {
             return false;
         } else {
@@ -41,15 +51,15 @@ public abstract class TileEntityLootable extends TileEntityContainer implements
                 nbttagcompound.setLong("LootTableSeed", this.h);
             }
 
-            return true;
+            return false; // Paper - always save the items, table may still remain
         }
     }
 
     public void d(@Nullable EntityHuman entityhuman) {
-        if (this.g != null && this.world.getMinecraftServer() != null) {
+        if (lootableData.shouldReplenish(entityhuman) && this.world.getMinecraftServer() != null) { // Paper
             LootTable loottable = this.world.getMinecraftServer().aP().a(this.g);
 
-            this.g = null;
+            lootableData.processRefill(entityhuman); // Paper
             Random random;
 
             if (this.h == 0L) {
@@ -152,4 +162,39 @@ public abstract class TileEntityLootable extends TileEntityContainer implements
     protected abstract NonNullList<ItemStack> q();
 
     protected abstract void a(NonNullList<ItemStack> nonnulllist);
+    // Paper start - LootTable API
+    @Override
+    public org.bukkit.loot.LootTable getLootTable() {
+        return getLootTableKey() != null ? Bukkit.getLootTable(CraftNamespacedKey.fromMinecraft(getLootTableKey())) : null;
+    }
+
+    @Override
+    public void setLootTable(org.bukkit.loot.LootTable table, long seed) {
+        setLootTable(table);
+        setSeed(seed);
+    }
+
+    @Override
+    public void setLootTable(org.bukkit.loot.LootTable table) {
+        MinecraftKey newKey = (table == null) ? null : CraftNamespacedKey.toMinecraft(table.getKey());
+        setLootTable(newKey);
+    }
+    private final CraftLootableInventoryData lootableData = new CraftLootableInventoryData(this);
+
+    @Override
+    public CraftLootableInventoryData getLootableData() {
+        return lootableData;
+    }
+
+    @Override
+    public LootableInventory getAPILootableInventory() {
+        return (LootableInventory) getBukkitWorld().getBlockAt(MCUtil.toLocation(world, getPosition())).getState();
+    }
+
+    @Override
+    public World getNMSWorld() {
+        return world;
+    }
+    // Paper end
+
 }
diff --git a/src/main/java/org/bukkit/craftbukkit/block/CraftBlockEntityState.java b/src/main/java/org/bukkit/craftbukkit/block/CraftBlockEntityState.java
index ac9b4297b2..0558cafe31 100644
--- a/src/main/java/org/bukkit/craftbukkit/block/CraftBlockEntityState.java
+++ b/src/main/java/org/bukkit/craftbukkit/block/CraftBlockEntityState.java
@@ -61,7 +61,7 @@ public class CraftBlockEntityState<T extends TileEntity> extends CraftBlockState
     }
 
     // gets the wrapped TileEntity
-    protected T getTileEntity() {
+    public T getTileEntity() { // Paper - protected -> public
         return tileEntity;
     }
 
diff --git a/src/main/java/org/bukkit/craftbukkit/block/CraftChest.java b/src/main/java/org/bukkit/craftbukkit/block/CraftChest.java
index dff5bb5171..e7b719b43d 100644
--- a/src/main/java/org/bukkit/craftbukkit/block/CraftChest.java
+++ b/src/main/java/org/bukkit/craftbukkit/block/CraftChest.java
@@ -1,6 +1,7 @@
 package org.bukkit.craftbukkit.block;
 
 import net.minecraft.server.BlockChest;
+import com.destroystokyo.paper.loottable.CraftLootableBlockInventory; // Paper
 import net.minecraft.server.BlockPosition;
 import net.minecraft.server.Blocks;
 import net.minecraft.server.ITileInventory;
@@ -15,7 +16,7 @@ import org.bukkit.craftbukkit.inventory.CraftInventory;
 import org.bukkit.craftbukkit.inventory.CraftInventoryDoubleChest;
 import org.bukkit.inventory.Inventory;
 
-public class CraftChest extends CraftLootable<TileEntityChest> implements Chest {
+public class CraftChest extends CraftLootable<TileEntityChest> implements Chest, CraftLootableBlockInventory { // Paper
 
     public CraftChest(final Block block) {
         super(block, TileEntityChest.class);
diff --git a/src/main/java/org/bukkit/craftbukkit/block/CraftLootable.java b/src/main/java/org/bukkit/craftbukkit/block/CraftLootable.java
index 34bcc49cf9..7ff7d33f06 100644
--- a/src/main/java/org/bukkit/craftbukkit/block/CraftLootable.java
+++ b/src/main/java/org/bukkit/craftbukkit/block/CraftLootable.java
@@ -1,5 +1,6 @@
 package org.bukkit.craftbukkit.block;
 
+import com.destroystokyo.paper.loottable.CraftLootableBlockInventory;
 import net.minecraft.server.MinecraftKey;
 import net.minecraft.server.TileEntityLootable;
 import org.bukkit.Bukkit;
@@ -11,7 +12,7 @@ import org.bukkit.craftbukkit.util.CraftNamespacedKey;
 import org.bukkit.loot.LootTable;
 import org.bukkit.loot.Lootable;
 
-public abstract class CraftLootable<T extends TileEntityLootable> extends CraftContainer<T> implements Nameable, Lootable {
+public abstract class CraftLootable<T extends TileEntityLootable> extends CraftContainer<T> implements Nameable, Lootable, CraftLootableBlockInventory {
 
     public CraftLootable(Block block, Class<T> tileEntityClass) {
         super(block, tileEntityClass);
@@ -69,7 +70,7 @@ public abstract class CraftLootable<T extends TileEntityLootable> extends CraftC
         setLootTable(getLootTable(), seed);
     }
 
-    private void setLootTable(LootTable table, long seed) {
+    public void setLootTable(LootTable table, long seed) { // Paper - public
         MinecraftKey key = (table == null) ? null : CraftNamespacedKey.toMinecraft(table.getKey());
         getSnapshot().a(key, seed); // PAIL setLootTable
     }
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftMinecartChest.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftMinecartChest.java
index 1b5b266c05..3d5225e9f2 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftMinecartChest.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftMinecartChest.java
@@ -1,5 +1,6 @@
 package org.bukkit.craftbukkit.entity;
 
+import com.destroystokyo.paper.loottable.CraftLootableEntityInventory; // Paper
 import net.minecraft.server.EntityMinecartChest;
 
 import org.bukkit.craftbukkit.CraftServer;
@@ -9,7 +10,7 @@ import org.bukkit.entity.minecart.StorageMinecart;
 import org.bukkit.inventory.Inventory;
 
 @SuppressWarnings("deprecation")
-public class CraftMinecartChest extends CraftMinecartContainer implements StorageMinecart {
+public class CraftMinecartChest extends CraftMinecartContainer implements StorageMinecart, CraftLootableEntityInventory { // Paper
     private final CraftInventory inventory;
 
     public CraftMinecartChest(CraftServer server, EntityMinecartChest entity) {
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftMinecartContainer.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftMinecartContainer.java
index 8ce9737451..7e11993aa6 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftMinecartContainer.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftMinecartContainer.java
@@ -47,7 +47,7 @@ public abstract class CraftMinecartContainer extends CraftMinecart implements Lo
         return getHandle().d; // PAIL rename lootTableSeed
     }
 
-    private void setLootTable(LootTable table, long seed) {
+    public void setLootTable(LootTable table, long seed) {
         MinecraftKey newKey = (table == null) ? null : CraftNamespacedKey.toMinecraft(table.getKey());
         getHandle().a(newKey, seed);
     }
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftMinecartHopper.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftMinecartHopper.java
index f29365c948..c51de47433 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftMinecartHopper.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftMinecartHopper.java
@@ -1,5 +1,6 @@
 package org.bukkit.craftbukkit.entity;
 
+import com.destroystokyo.paper.loottable.CraftLootableEntityInventory; // Paper
 import net.minecraft.server.EntityMinecartHopper;
 
 import org.bukkit.craftbukkit.CraftServer;
@@ -8,7 +9,7 @@ import org.bukkit.entity.EntityType;
 import org.bukkit.entity.minecart.HopperMinecart;
 import org.bukkit.inventory.Inventory;
 
-public final class CraftMinecartHopper extends CraftMinecartContainer implements HopperMinecart {
+public final class CraftMinecartHopper extends CraftMinecartContainer implements HopperMinecart, CraftLootableEntityInventory { // Paper
     private final CraftInventory inventory;
 
     public CraftMinecartHopper(CraftServer server, EntityMinecartHopper entity) {
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftMob.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftMob.java
index eb643cff3a..a3789c86b0 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftMob.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftMob.java
@@ -1,6 +1,7 @@
 package org.bukkit.craftbukkit.entity;
 
 import net.minecraft.server.EntityInsentient;
+import net.minecraft.server.MinecraftKey;
 import org.bukkit.Bukkit;
 import org.bukkit.NamespacedKey;
 import org.bukkit.craftbukkit.CraftServer;
@@ -46,6 +47,13 @@ public abstract class CraftMob extends CraftLivingEntity implements Mob {
         getHandle().bI = (table == null) ? null : CraftNamespacedKey.toMinecraft(table.getKey()); // PAIL rename lootTableKey
     }
 
+    // Paper start
+    public void setLootTable(LootTable table, long seed) {
+        setLootTable(table);
+        setSeed(seed);
+    }
+    // Paper end
+
     @Override
     public LootTable getLootTable() {
         if (getHandle().bI == null) {
-- 
2.18.0