From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Wed, 6 Feb 2019 00:19:33 -0500
Subject: [PATCH] BlockDestroyEvent

Adds an event for when the server is going to destroy a current block,
potentially causing it to drop. This event can be cancelled to avoid
the block destruction, such as preventing signs from popping when
floating in the air.

This can replace many uses of BlockPhysicsEvent

diff --git a/src/main/java/com/destroystokyo/paper/event/block/BlockDestroyEvent.java b/src/main/java/com/destroystokyo/paper/event/block/BlockDestroyEvent.java
new file mode 100644
index 0000000000000000000000000000000000000000..278f26bed374fe79ff3cd135a76f019bd21906e4
--- /dev/null
+++ b/src/main/java/com/destroystokyo/paper/event/block/BlockDestroyEvent.java
@@ -0,0 +1,123 @@
+package com.destroystokyo.paper.event.block;
+
+import org.bukkit.block.Block;
+import org.bukkit.block.data.BlockData;
+import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
+import org.bukkit.event.block.BlockExpEvent;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Fired anytime the server intends to 'destroy' a block through some triggering reason.
+ * This does not fire anytime a block is set to air, but only with more direct triggers such
+ * as physics updates, pistons, Entities changing blocks, commands set to "Destroy".
+ *
+ * This event is associated with the game playing a sound effect at the block in question, when
+ * something can be described as "intend to destroy what is there",
+ *
+ * Events such as leaves decaying, pistons retracting (where the block is moving), does NOT fire this event.
+ *
+ */
+public class BlockDestroyEvent extends BlockExpEvent implements Cancellable {
+
+    private static final HandlerList handlers = new HandlerList();
+
+    @NotNull private final BlockData newState;
+    private boolean willDrop;
+    private boolean playEffect = true;
+    private BlockData effectBlock;
+
+    private boolean cancelled = false;
+
+    @ApiStatus.Internal
+    public BlockDestroyEvent(@NotNull Block block, @NotNull BlockData newState, @NotNull BlockData effectBlock, int xp, boolean willDrop) {
+        super(block, xp);
+        this.newState = newState;
+        this.effectBlock = effectBlock;
+        this.willDrop = willDrop;
+    }
+
+    /**
+     * Get the effect that will be played when the block is broken.
+     * @return block break effect
+     */
+    @NotNull
+    public BlockData getEffectBlock() {
+        return this.effectBlock;
+    }
+
+    /**
+     * Sets the effect that will be played when the block is broken.
+     * Note: {@link BlockDestroyEvent#playEffect()} must be true in order for this effect to be
+     * played.
+     *
+     * @param effectBlock block effect
+     */
+    public void setEffectBlock(@NotNull BlockData effectBlock) {
+        this.effectBlock = effectBlock;
+    }
+
+    /**
+     * @return The new state of this block (Air, or a Fluid type)
+     */
+    @NotNull
+    public BlockData getNewState() {
+        return newState;
+    }
+
+    /**
+     * @return If the server is going to drop the block in question with this destroy event
+     */
+    public boolean willDrop() {
+        return this.willDrop;
+    }
+
+    /**
+     * @param willDrop If the server is going to drop the block in question with this destroy event
+     */
+    public void setWillDrop(boolean willDrop) {
+        this.willDrop = willDrop;
+    }
+
+    /**
+     * @return If the server is going to play the sound effect for this destruction
+     */
+    public boolean playEffect() {
+        return this.playEffect;
+    }
+
+    /**
+     * @param playEffect If the server should play the sound effect for this destruction
+     */
+    public void setPlayEffect(boolean playEffect) {
+        this.playEffect = playEffect;
+    }
+
+    /**
+     * @return If the event is cancelled, meaning the block will not be destroyed
+     */
+    @Override
+    public boolean isCancelled() {
+        return cancelled;
+    }
+
+    /**
+     * If the event is cancelled, the block will remain in its previous state.
+     * @param cancel true if you wish to cancel this event
+     */
+    @Override
+    public void setCancelled(boolean cancel) {
+        cancelled = cancel;
+    }
+
+    @NotNull
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    @NotNull
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
+}