PaperMC/nms-patches/BlockDoor.patch

--- a/net/minecraft/server/BlockDoor.java
+++ b/net/minecraft/server/BlockDoor.java
@@ -2,6 +2,8 @@
 
 import java.util.Random;
 
+import org.bukkit.event.block.BlockRedstoneEvent; // CraftBukkit
+
 public class BlockDoor extends Block {
 
     public static final BlockStateDirection FACING = BlockFacingHorizontal.FACING;
@@ -137,9 +139,23 @@
                     this.b(world, blockposition, iblockdata, 0);
                 }
             } else {
-                boolean flag1 = world.isBlockIndirectlyPowered(blockposition) || world.isBlockIndirectlyPowered(blockposition3);
 
-                if (block != this && (flag1 || block.getBlockData().n()) && flag1 != ((Boolean) iblockdata2.get(BlockDoor.POWERED)).booleanValue()) {
+                // CraftBukkit start
+                org.bukkit.World bworld = world.getWorld();
+                org.bukkit.block.Block bukkitBlock = bworld.getBlockAt(blockposition.getX(), blockposition.getY(), blockposition.getZ());
+                org.bukkit.block.Block blockTop = bworld.getBlockAt(blockposition3.getX(), blockposition3.getY(), blockposition3.getZ());
+
+                int power = bukkitBlock.getBlockPower();
+                int powerTop = blockTop.getBlockPower();
+                if (powerTop > power) power = powerTop;
+                int oldPower = (Boolean) iblockdata2.get(BlockDoor.POWERED) ? 15 : 0;
+
+                if (oldPower == 0 ^ power == 0) {
+                    BlockRedstoneEvent eventRedstone = new BlockRedstoneEvent(bukkitBlock, oldPower, power);
+                    world.getServer().getPluginManager().callEvent(eventRedstone);
+
+                    boolean flag1 = eventRedstone.getNewCurrent() > 0;
+                    // CraftBukkit end
                     world.setTypeAndData(blockposition3, iblockdata2.set(BlockDoor.POWERED, Boolean.valueOf(flag1)), 2);
                     if (flag1 != ((Boolean) iblockdata.get(BlockDoor.OPEN)).booleanValue()) {
                         world.setTypeAndData(blockposition, iblockdata.set(BlockDoor.OPEN, Boolean.valueOf(flag1)), 2);