cuberite-2a/src/Blocks/BlockPiston.h

#pragma once

#include "BlockHandler.h"

#include <unordered_set>


class cWorld;


class cBlockPistonHandler :
	public cBlockHandler
{
public:
	cBlockPistonHandler(BLOCKTYPE a_BlockType);

	virtual void OnDestroyed(cChunkInterface & a_ChunkInterface, cWorldInterface & a_WorldInterface, int a_BlockX, int a_BlockY, int a_BlockZ) override;

	virtual void ConvertToPickups(cItems & a_Pickups, NIBBLETYPE a_BlockMeta) override;

	virtual bool GetPlacementBlockTypeMeta(
		cChunkInterface & a_ChunkInterface, cPlayer * a_Player,
		int a_BlockX, int a_BlockY, int a_BlockZ, eBlockFace a_BlockFace,
		int a_CursorX, int a_CursorY, int a_CursorZ,
		BLOCKTYPE & a_BlockType, NIBBLETYPE & a_BlockMeta
	) override;

	static NIBBLETYPE RotationPitchToMetaData(double a_Rotation, double a_Pitch)
	{
		if (a_Pitch >= 50)
		{
			return 0x1;
		}
		else if (a_Pitch <= -50)
		{
			return 0x0;
		}
		else
		{
			a_Rotation += 90 + 45;  // So its not aligned with axis

			if (a_Rotation > 360)
			{
				a_Rotation -= 360;
			}
			if ((a_Rotation >= 0) && (a_Rotation < 90))
			{
				return 0x4;
			}
			else if ((a_Rotation >= 180) && (a_Rotation < 270))
			{
				return 0x5;
			}
			else if ((a_Rotation >= 90) && (a_Rotation < 180))
			{
				return 0x2;
			}
			else
			{
				return 0x3;
			}
		}
	}

	static eBlockFace MetaDataToDirection(NIBBLETYPE a_MetaData)
	{
		switch (a_MetaData & 0x7)  // We only want the bottom three bits (4th controls extended-ness))
		{
			case 0x0: return BLOCK_FACE_YM;
			case 0x1: return BLOCK_FACE_YP;
			case 0x2: return BLOCK_FACE_ZM;
			case 0x3: return BLOCK_FACE_ZP;
			case 0x4: return BLOCK_FACE_XM;
			case 0x5: return BLOCK_FACE_XP;
			default:
			{
				ASSERT(!"Invalid Metadata");
				return BLOCK_FACE_NONE;
			}
		}
	}

	/** Converts piston block's metadata into a unit vector representing the direction in which the piston will extend. */
	static Vector3i MetadataToOffset(NIBBLETYPE a_PistonMeta);

	static void ExtendPiston(Vector3i a_BlockPos, cWorld * a_World);
	static void RetractPiston(Vector3i a_BlockPos, cWorld * a_World);

	virtual ColourID GetMapBaseColourID(NIBBLETYPE a_Meta) override
	{
		UNUSED(a_Meta);
		return 11;
	}

	/** Returns true if the piston (with the specified meta) is extended */
	static inline bool IsExtended(NIBBLETYPE a_PistonMeta) { return ((a_PistonMeta & 0x8) != 0x0); }

private:

	typedef std::unordered_set<Vector3i, VectorHasher<int>> Vector3iSet;

	/** Returns true if the piston (specified by blocktype) is a sticky piston */
	static inline bool IsSticky(BLOCKTYPE a_BlockType) { return (a_BlockType == E_BLOCK_STICKY_PISTON); }

	/** Returns true if the specified block can be pushed by a piston (and left intact) */
	static inline bool CanPush(BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta)
	{
		switch (a_BlockType)
		{
			case E_BLOCK_ANVIL:
			case E_BLOCK_BARRIER:
			case E_BLOCK_BEACON:
			case E_BLOCK_BEDROCK:
			case E_BLOCK_BREWING_STAND:
			case E_BLOCK_CHAIN_COMMAND_BLOCK:
			case E_BLOCK_CHEST:
			case E_BLOCK_COMMAND_BLOCK:
			case E_BLOCK_DAYLIGHT_SENSOR:
			case E_BLOCK_DISPENSER:
			case E_BLOCK_DROPPER:
			case E_BLOCK_ENCHANTMENT_TABLE:
			case E_BLOCK_END_GATEWAY:
			case E_BLOCK_END_PORTAL:
			case E_BLOCK_END_PORTAL_FRAME:
			// Notice the lack of an E_BLOCK_ENDER_CHEST here; its because ender chests can totally be pushed / pulled in MCS :)
			case E_BLOCK_FURNACE:
			case E_BLOCK_LIT_FURNACE:
			case E_BLOCK_INVERTED_DAYLIGHT_SENSOR:
			case E_BLOCK_HOPPER:
			case E_BLOCK_JUKEBOX:
			case E_BLOCK_MOB_SPAWNER:
			case E_BLOCK_NETHER_PORTAL:
			case E_BLOCK_NOTE_BLOCK:
			case E_BLOCK_OBSIDIAN:
			case E_BLOCK_PISTON_EXTENSION:
			case E_BLOCK_REPEATING_COMMAND_BLOCK:
			case E_BLOCK_STANDING_BANNER:
			case E_BLOCK_STRUCTURE_BLOCK:
			case E_BLOCK_TRAPPED_CHEST:
			case E_BLOCK_WALL_BANNER:
			{
				return false;
			}
			case E_BLOCK_STICKY_PISTON:
			case E_BLOCK_PISTON:
			{
				// A piston can only be pushed if retracted:
				return !IsExtended(a_BlockMeta);
			}
		}
		return true;
	}

	/** Tries to push a block and increases the pushed blocks variable. Returns true if the block is pushable */
	static bool CanPushBlock(
		const Vector3i & a_BlockPos, cWorld * a_World, bool a_RequirePushable,
		Vector3iSet & a_BlocksPushed, const Vector3i & a_PushDir
	);

	/** Moves a list of blocks in a specific direction */
	static void PushBlocks(const Vector3iSet & a_BlocksToPush,
		cWorld * a_World, const Vector3i & a_PushDir
	);
} ;





class cBlockPistonHeadHandler :
	public cBlockHandler
{
	typedef cBlockHandler super;

public:
	cBlockPistonHeadHandler(void);

	virtual void OnDestroyedByPlayer(cChunkInterface & a_ChunkInterface, cWorldInterface & a_WorldInterface, cPlayer * a_Player, int a_BlockX, int a_BlockY, int a_BlockZ) override;

	virtual void ConvertToPickups(cItems & a_Pickups, NIBBLETYPE a_BlockMeta) override
	{
		// No pickups
		// Also with 1.7, the item forms of these technical blocks have been removed, so giving someone this will crash their client...
	}
} ;