Implement SaplingGrowTreeEvent and BlockEvent.FarmlandTrampleEvent (#146)

* Implement SaplingGrowTreeEvent and BlockEvent.FarmlandTrampleEvent

* Requested changes

* Has result

* Fix imports

* Fix checkstyle

Co-authored-by: JFronny <33260128+JFronny@users.noreply.github.com>
Co-authored-by: Glitch <glitchieproductionsofficial@gmail.com>

Author: 3 people

patchwork-events-world/src/main/java/net/minecraftforge/event/world/ChunkEvent.java

@@ -31,7 +31,7 @@
  * If a method utilizes this {@link net.minecraftforge.eventbus.api.Event} as
  * its parameter, the method will receive every child event of this class.<br>
  * <br>
- * {@link #Chunk} contains the Chunk this event is affecting.<br>
+ * {@link #chunk} contains the Chunk this event is affecting.<br>
  * <br>
  * All children of this event are fired on the
  * {@link MinecraftForge#EVENT_BUS}.<br>

patchwork-events-world/src/main/java/net/minecraftforge/event/world/SaplingGrowTreeEvent.java

@@ -0,0 +1,65 @@
+/*
+ * Minecraft Forge, Patchwork Project
+ * Copyright (c) 2016-2020, 2019-2020
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation version 2.1
+ * of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+package net.minecraftforge.event.world;
+
+import java.util.Random;
+
+import net.minecraft.block.BlockState;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.IWorld;
+
+/**
+ * SaplingGrowTreeEvent is fired when a sapling grows into a tree.
+ *
+ * <p>This event is fired during sapling growth in
+ * {@link net.minecraft.block.SaplingBlock#generate(IWorld, BlockPos, BlockState, Random)}.
+ *
+ * <p>{@link #pos} contains the coordinates of the growing sapling.
+ * {@link #rand} contains an instance of Random for use.
+ *
+ * <p>This event is not cancellable.
+ *
+ * <p>This event has a result.
+ * This result determines if the sapling is allowed to grow.
+ */
+
+public class SaplingGrowTreeEvent extends WorldEvent {
+	private final BlockPos pos;
+	private final Random rand;
+
+	public SaplingGrowTreeEvent(IWorld world, Random rand, BlockPos pos) {
+		super(world);
+		this.rand = rand;
+		this.pos = pos;
+	}
+
+	public BlockPos getPos() {
+		return pos;
+	}
+
+	public Random getRand() {
+		return rand;
+	}
+
+	@Override
+	public boolean hasResult() {
+		return true;
+	}
+}

patchwork-events-world/src/main/java/net/patchworkmc/impl/event/world/WorldEvents.java

@@ -21,13 +21,16 @@
 
 import java.util.Collections;
 import java.util.List;
+import java.util.Random;
 
 import javax.annotation.Nullable;
 
 import net.minecraftforge.common.MinecraftForge;
 import net.minecraftforge.event.world.ChunkEvent;
 import net.minecraftforge.event.world.ChunkWatchEvent;
+import net.minecraftforge.event.world.SaplingGrowTreeEvent;
 import net.minecraftforge.event.world.WorldEvent;
+import net.minecraftforge.eventbus.api.Event;
 
 import net.minecraft.entity.EntityCategory;
 import net.minecraft.server.network.ServerPlayerEntity;
@@ -105,4 +108,10 @@ public void onInitialize() {
 		// Fire ChunkEvent.Unload on server side
 		ServerChunkEvents.CHUNK_UNLOAD.register((server, chunk) -> MinecraftForge.EVENT_BUS.post(new ChunkEvent.Unload(chunk)));
 	}
+
+	public static boolean onSaplingGrowTree(IWorld world, Random rand, BlockPos pos) {
+		SaplingGrowTreeEvent event = new SaplingGrowTreeEvent(world, rand, pos);
+		MinecraftForge.EVENT_BUS.post(event);
+		return event.getResult() != Event.Result.DENY;
+	}
 }

patchwork-events-world/src/main/java/net/patchworkmc/mixin/event/world/MixinSaplingBlock.java

@@ -0,0 +1,44 @@
+/*
+ * Minecraft Forge, Patchwork Project
+ * Copyright (c) 2016-2020, 2019-2020
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation version 2.1
+ * of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+package net.patchworkmc.mixin.event.world;
+
+import java.util.Random;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+import net.minecraft.block.BlockState;
+import net.minecraft.block.SaplingBlock;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.IWorld;
+
+import net.patchworkmc.impl.event.world.WorldEvents;
+
+@Mixin(SaplingBlock.class)
+public class MixinSaplingBlock {
+	@Inject(method = "generate", at = @At(value = "INVOKE", target = "Lnet/minecraft/block/sapling/SaplingGenerator;generate(Lnet/minecraft/world/IWorld;Lnet/minecraft/util/math/BlockPos;Lnet/minecraft/block/BlockState;Ljava/util/Random;)Z"), cancellable = true)
+	private void onGenerateTree(IWorld world, BlockPos pos, BlockState state, Random random, CallbackInfo ci) {
+		if (!WorldEvents.onSaplingGrowTree(world, random, pos)) {
+			ci.cancel();
+		}
+	}
+}

patchwork-events-world/src/main/resources/patchwork-events-world.mixins.json

@@ -5,6 +5,7 @@
   "mixins": [
     "MixinChunkGenerator",
     "MixinMinecraftServer",
+    "MixinSaplingBlock",
     "MixinServerWorld",
     "MixinSpawnHelper",
     "MixinThreadedAnvilChunkStorage"

patchwork-extensions-block/src/main/java/net/minecraftforge/event/world/BlockEvent.java

@@ -24,6 +24,7 @@
 import net.minecraftforge.common.extensions.IForgeBlockState;
 import net.minecraftforge.eventbus.api.Event;
 
+import net.minecraft.entity.Entity;
 import net.minecraft.item.ItemStack;
 import net.minecraft.util.DefaultedList;
 import net.minecraft.block.BlockState;
@@ -166,4 +167,32 @@ public PlayerEntity getHarvester() {
 			return harvester;
 		}
 	}
+
+	/**
+	 * Fired when when farmland gets trampled
+	 * This event is cancellable.
+	 */
+	public static class FarmlandTrampleEvent extends BlockEvent {
+		private final Entity entity;
+		private final float fallDistance;
+
+		public FarmlandTrampleEvent(World world, BlockPos pos, BlockState state, float fallDistance, Entity entity) {
+			super(world, pos, state);
+			this.entity = entity;
+			this.fallDistance = fallDistance;
+		}
+
+		public Entity getEntity() {
+			return entity;
+		}
+
+		public float getFallDistance() {
+			return fallDistance;
+		}
+
+		@Override
+		public boolean isCancelable() {
+			return true;
+		}
+	}
 }

patchwork-extensions-block/src/main/java/net/patchworkmc/impl/extensions/block/BlockHarvestManager.java

@@ -35,6 +35,7 @@
 import net.minecraft.block.RedstoneOreBlock;
 import net.minecraft.block.SpawnerBlock;
 import net.minecraft.block.entity.BlockEntity;
+import net.minecraft.entity.Entity;
 import net.minecraft.entity.player.PlayerEntity;
 import net.minecraft.item.ItemStack;
 import net.minecraft.network.packet.s2c.play.BlockEntityUpdateS2CPacket;
@@ -170,4 +171,13 @@ public static float fireBlockHarvesting(DefaultedList<ItemStack> drops, World wo
 		MinecraftForge.EVENT_BUS.post(event);
 		return event.getDropChance();
 	}
+
+	public static boolean onFarmlandTrample(World world, BlockPos pos, BlockState state, float fallDistance, Entity entity) {
+		// TODO: In forge, the possibility of trampling is handled by IForgeEntity.canTrample
+		// Maybe there's a good way to reconcile that to not break any Fabric mods trying to
+		// manipulate crop trampling, but for now I just let the vanilla check do it's thing.
+		BlockEvent.FarmlandTrampleEvent event = new BlockEvent.FarmlandTrampleEvent(world, pos, state, fallDistance, entity);
+		MinecraftForge.EVENT_BUS.post(event);
+		return !event.isCanceled();
+	}
 }

patchwork-extensions-block/src/main/java/net/patchworkmc/mixin/extensions/block/MixinFarmlandBlock.java

@@ -24,16 +24,26 @@
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
 
+import net.minecraft.block.Block;
 import net.minecraft.block.BlockState;
 import net.minecraft.block.FarmlandBlock;
+import net.minecraft.entity.Entity;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.Direction;
 import net.minecraft.world.BlockView;
+import net.minecraft.world.World;
+
+import net.patchworkmc.impl.extensions.block.BlockHarvestManager;
 
 @Mixin(FarmlandBlock.class)
-public class MixinFarmlandBlock {
+public class MixinFarmlandBlock extends Block {
+	public MixinFarmlandBlock() {
+		super(null);
+	}
+
 	@Inject(method = "hasCrop", cancellable = true, at = @At("HEAD"))
 	private static void onHasCrop(BlockView world, BlockPos pos, CallbackInfoReturnable<Boolean> cir) {
 		final BlockState ourState = world.getBlockState(pos);
@@ -44,4 +54,12 @@ private static void onHasCrop(BlockView world, BlockPos pos, CallbackInfoReturna
 			cir.cancel();
 		}
 	}
+
+	@Inject(method = "onLandedUpon", at = @At(value = "INVOKE", target = "Lnet/minecraft/block/FarmlandBlock;setToDirt(Lnet/minecraft/block/BlockState;Lnet/minecraft/world/World;Lnet/minecraft/util/math/BlockPos;)V"), cancellable = true)
+	private void onSetToDirt(World world, BlockPos pos, Entity entity, float distance, CallbackInfo ci) {
+		if (!BlockHarvestManager.onFarmlandTrample(world, pos, world.getBlockState(pos), distance, entity)) {
+			super.onLandedUpon(world, pos, entity, distance);
+			ci.cancel();
+		}
+	}
 }

patchwork-god-classes/src/main/java/net/minecraftforge/common/ForgeHooks.java

@@ -28,6 +28,7 @@
 import net.minecraftforge.event.ForgeEventFactory;
 import net.minecraftforge.eventbus.api.Event;
 
+import net.minecraft.block.BlockState;
 import net.minecraft.world.dimension.DimensionType;
 import net.minecraft.entity.Entity;
 import net.minecraft.entity.ItemEntity;
@@ -142,4 +143,8 @@ public static LootTable loadLootTable(Gson gson, Identifier name, JsonObject dat
 	public static String readPoolName(JsonObject json) {
 		return LootHooks.readPoolName(json);
 	}
+
+	public static boolean onFarmlandTrample(World world, BlockPos pos, BlockState state, float fallDistance, Entity entity) {
+		return BlockHarvestManager.onFarmlandTrample(world, pos, state, fallDistance, entity);
+	}
 }

patchwork-god-classes/src/main/java/net/minecraftforge/event/ForgeEventFactory.java

@@ -19,6 +19,8 @@
 
 package net.minecraftforge.event;
 
+import java.util.Random;
+
 import javax.annotation.Nullable;
 
 import net.minecraftforge.common.capabilities.CapabilityDispatcher;
@@ -38,18 +40,19 @@
 import net.minecraft.loot.LootTable;
 import net.minecraft.util.Identifier;
 import net.minecraft.util.hit.HitResult;
+import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.IWorld;
 import net.minecraft.world.MobSpawnerLogic;
 import net.minecraft.world.World;
 import net.minecraft.block.BlockState;
 import net.minecraft.item.ItemStack;
 import net.minecraft.util.DefaultedList;
-import net.minecraft.util.math.BlockPos;
 
 import net.patchworkmc.impl.capability.CapabilityEvents;
 import net.patchworkmc.impl.event.entity.EntityEvents;
 import net.patchworkmc.impl.event.entity.PlayerEvents;
 import net.patchworkmc.impl.event.loot.LootEvents;
+import net.patchworkmc.impl.event.world.WorldEvents;
 import net.patchworkmc.impl.extensions.block.BlockHarvestManager;
 
 /*
@@ -87,6 +90,10 @@ public static LootTable loadLootTable(Identifier name, LootTable table, LootMana
 		return LootEvents.loadLootTable(name, table, lootTableManager);
 	}
 
+	public static boolean saplingGrowTree(IWorld world, Random rand, BlockPos pos) {
+		return WorldEvents.onSaplingGrowTree(world, rand, pos);
+	}
+
 	// Forge might remove BlockEvent.HarvestDropsEvent, which is replaced by the new loot modifier.
 	@Deprecated
 	public static float fireBlockHarvesting(DefaultedList<ItemStack> drops, World world, BlockPos pos, BlockState state, int fortune, float dropChance, boolean silkTouch, PlayerEntity player) {