Implemented coral and coral fans

this implementation is very rough due to having to hack around lots more MCPE bullshit, and currently doesn't allow dynamic coral types; but it's there. We'll clean this up after 1.13 migration is done.

src/block/WallCoralFan.php

@@ -0,0 +1,78 @@
+<?php
+
+/*
+ *
+ *  ____            _        _   __  __ _                  __  __ ____
+ * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \
+ * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
+ * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/
+ * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_|
+ *
+ * This program 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, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * @author PocketMine Team
+ * @link http://www.pocketmine.net/
+ *
+ *
+*/
+
+declare(strict_types=1);
+
+namespace pocketmine\block;
+
+use pocketmine\block\utils\BlockDataSerializer;
+use pocketmine\block\utils\HorizontalFacingTrait;
+use pocketmine\data\bedrock\CoralTypeIdMap;
+use pocketmine\item\Item;
+use pocketmine\item\ItemFactory;
+use pocketmine\item\ItemIds;
+use pocketmine\math\Axis;
+use pocketmine\math\Facing;
+use pocketmine\math\Vector3;
+use pocketmine\player\Player;
+use pocketmine\world\BlockTransaction;
+
+final class WallCoralFan extends BaseCoral{
+	use HorizontalFacingTrait;
+
+	public function readStateFromData(int $id, int $stateMeta) : void{
+		$this->facing = BlockDataSerializer::readCoralFacing($stateMeta >> 2);
+		$this->dead = ($stateMeta & BlockLegacyMetadata::CORAL_FAN_HANG_FLAG_DEAD) !== 0;
+	}
+
+	public function writeStateToMeta() : int{
+		return (BlockDataSerializer::writeCoralFacing($this->facing) << 2) | ($this->dead ? BlockLegacyMetadata::CORAL_FAN_HANG_FLAG_DEAD : 0);
+	}
+
+	public function getStateBitmask() : int{
+		return 0b1110;
+	}
+
+	public function asItem() : Item{
+		return ItemFactory::getInstance()->get(
+			$this->dead ? ItemIds::CORAL_FAN_DEAD : ItemIds::CORAL_FAN,
+			CoralTypeIdMap::getInstance()->toId($this->coralType)
+		);
+	}
+
+	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
+		$axis = Facing::axis($face);
+		if(($axis !== Axis::X && $axis !== Axis::Z) || !$blockClicked->isSolid()){
+			return false;
+		}
+		$this->facing = $face;
+		return parent::place($tx, $item, $blockReplace, $blockClicked, $face, $clickVector, $player);
+	}
+
+	public function onNearbyBlockChange() : void{
+		$world = $this->pos->getWorld();
+		if(!$world->getBlock($this->pos->getSide(Facing::opposite($this->facing)))->isSolid()){
+			$world->useBreakOn($this->pos);
+		}else{
+			parent::onNearbyBlockChange();
+		}
+	}
+}