Implement cauldrons (#5163)

the following things are currently not implemented:

- particle/sound effects when an entity extinguishes itself
- particle/sound effects when mixing different stuff in a cauldron
- powder snow cauldron

both of these things are contingent on #5169, but for the time being, the PR is functionally complete and I want to move on to something else without being stalled by the particle+sound problem (which I haven't yet decided how to solve).

src/block/FillableCauldron.php

@@ -0,0 +1,132 @@
+<?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\SupportType;
+use pocketmine\data\runtime\RuntimeDataReader;
+use pocketmine\data\runtime\RuntimeDataWriter;
+use pocketmine\item\Item;
+use pocketmine\math\AxisAlignedBB;
+use pocketmine\math\Facing;
+use pocketmine\world\sound\Sound;
+use function min;
+
+abstract class FillableCauldron extends Transparent{
+	public const MIN_FILL_LEVEL = 1;
+	public const MAX_FILL_LEVEL = 6;
+
+	private int $fillLevel = self::MIN_FILL_LEVEL;
+
+	public function getRequiredStateDataBits() : int{
+		return 3;
+	}
+
+	protected function describeState(RuntimeDataReader|RuntimeDataWriter $w) : void{
+		$w->boundedInt(3, self::MIN_FILL_LEVEL, self::MAX_FILL_LEVEL, $this->fillLevel);
+	}
+
+	public function getFillLevel() : int{ return $this->fillLevel; }
+
+	/** @return $this */
+	public function setFillLevel(int $fillLevel) : self{
+		if($fillLevel < self::MIN_FILL_LEVEL || $fillLevel > self::MAX_FILL_LEVEL){
+			throw new \InvalidArgumentException("Fill level must be in range " . self::MIN_FILL_LEVEL . " ... " . self::MAX_FILL_LEVEL);
+		}
+		$this->fillLevel = $fillLevel;
+		return $this;
+	}
+
+	protected function recalculateCollisionBoxes() : array{
+		$result = [
+			AxisAlignedBB::one()->trim(Facing::UP, 11 / 16) //bottom of the cauldron
+		];
+
+		foreach(Facing::HORIZONTAL as $f){ //add the frame parts around the bowl
+			$result[] = AxisAlignedBB::one()->trim($f, 14 / 16);
+		}
+		return $result;
+	}
+
+	public function getSupportType(int $facing) : SupportType{
+		return $facing === Facing::UP ? SupportType::EDGE() : SupportType::NONE();
+	}
+
+	protected function withFillLevel(int $fillLevel) : Block{
+		return $fillLevel === 0 ? VanillaBlocks::CAULDRON() : $this->setFillLevel(min(self::MAX_FILL_LEVEL, $fillLevel));
+	}
+
+	/**
+	 * @param Item[] &$returnedItems
+	 */
+	protected function addFillLevels(int $amount, Item $usedItem, Item $returnedItem, array &$returnedItems) : void{
+		if($this->fillLevel >= self::MAX_FILL_LEVEL){
+			return;
+		}
+		$this->position->getWorld()->setBlock($this->position, $this->withFillLevel($this->fillLevel + $amount));
+		$this->position->getWorld()->addSound($this->position->add(0.5, 0.5, 0.5), $this->getFillSound());
+
+		$usedItem->pop();
+		$returnedItems[] = $returnedItem;
+	}
+
+	/**
+	 * @param Item[] &$returnedItems
+	 */
+	protected function removeFillLevels(int $amount, Item $usedItem, Item $returnedItem, array &$returnedItems) : void{
+		if($this->fillLevel < $amount){
+			return;
+		}
+
+		$this->position->getWorld()->setBlock($this->position, $this->withFillLevel($this->fillLevel - $amount));
+		$this->position->getWorld()->addSound($this->position->add(0.5, 0.5, 0.5), $this->getEmptySound());
+
+		$usedItem->pop();
+		$returnedItems[] = $returnedItem;
+	}
+
+	/**
+	 * Returns the sound played when adding levels to the cauldron liquid.
+	 */
+	abstract public function getFillSound() : Sound;
+
+	/**
+	 * Returns the sound played when removing levels from the cauldron liquid.
+	 */
+	abstract public function getEmptySound() : Sound;
+
+	/**
+	 * @param Item[] &$returnedItems
+	 */
+	protected function mix(Item $usedItem, Item $returnedItem, array &$returnedItems) : void{
+		$this->position->getWorld()->setBlock($this->position, VanillaBlocks::CAULDRON());
+		//TODO: sounds and particles
+
+		$usedItem->pop();
+		$returnedItems[] = $returnedItem;
+	}
+
+	public function asItem() : Item{
+		return VanillaBlocks::CAULDRON()->asItem();
+	}
+}