path: root/src/ClientHandle.cpp

#include "Globals.h"  // NOTE: MSVC stupidness requires this to be the same across all modules

#include "ClientHandle.h"
#include "BlockInfo.h"
#include "Server.h"
#include "World.h"
#include "Chunk.h"
#include "Entities/Pickup.h"
#include "Bindings/PluginManager.h"
#include "Entities/Player.h"
#include "Entities/Minecart.h"
#include "Inventory.h"
#include "BlockEntities/BeaconEntity.h"
#include "BlockEntities/ChestEntity.h"
#include "BlockEntities/CommandBlockEntity.h"
#include "BlockEntities/SignEntity.h"
#include "UI/InventoryWindow.h"
#include "UI/CraftingWindow.h"
#include "UI/Window.h"
#include "UI/AnvilWindow.h"
#include "UI/BeaconWindow.h"
#include "UI/EnchantingWindow.h"
#include "Item.h"
#include "Mobs/Monster.h"
#include "ChatColor.h"
#include "Items/ItemHandler.h"
#include "Blocks/BlockHandler.h"
#include "Blocks/BlockBed.h"
#include "Blocks/ChunkInterface.h"
#include "BlockInServerPluginInterface.h"

#include "Root.h"

#include "Protocol/Authenticator.h"
#include "Protocol/Protocol.h"
#include "CompositeChat.h"
#include "Items/ItemSword.h"

#include "mbedtls/md5.h"



/** Maximum number of explosions to send this tick, server will start dropping if exceeded. */
#define MAX_EXPLOSIONS_PER_TICK 20

/** Maximum number of block change interactions a player can perform per tick - exceeding this causes a kick. */
#define MAX_BLOCK_CHANGE_INTERACTIONS 20

/** Maximum number of bytes that a chat message sent by a player may consist of. */
#define MAX_CHAT_MSG_LENGTH 1024

/** Maximum number of chunks to stream per tick. */
#define MAX_CHUNKS_STREAMED_PER_TICK 4





int cClientHandle::s_ClientCount = 0;


float cClientHandle::FASTBREAK_PERCENTAGE;



////////////////////////////////////////////////////////////////////////////////
// cClientHandle:

cClientHandle::cClientHandle(const AString & a_IPString, int a_ViewDistance) :
	m_ForgeHandshake(this),
	m_CurrentViewDistance(a_ViewDistance),
	m_RequestedViewDistance(a_ViewDistance),
	m_IPString(a_IPString),
	m_Player(nullptr),
	m_CachedSentChunk(std::numeric_limits<decltype(m_CachedSentChunk.m_ChunkX)>::max(), std::numeric_limits<decltype(m_CachedSentChunk.m_ChunkZ)>::max()),
	m_HasSentDC(false),
	m_LastStreamedChunkX(std::numeric_limits<decltype(m_LastStreamedChunkX)>::max()),  // bogus chunk coords to force streaming upon login
	m_LastStreamedChunkZ(std::numeric_limits<decltype(m_LastStreamedChunkZ)>::max()),
	m_TicksSinceLastPacket(0),
	m_Ping(1000),
	m_PingID(1),
	m_BlockDigAnimStage(-1),
	m_BlockDigAnimSpeed(0),
	m_BlockDigAnimX(0),
	m_BlockDigAnimY(cChunkDef::Height + 1),  // Invalid Y, so that the coords don't get picked up
	m_BlockDigAnimZ(0),
	m_HasStartedDigging(false),
	m_LastDigBlockX(0),
	m_LastDigBlockY(cChunkDef::Height + 1),  // Invalid Y, so that the coords don't get picked up
	m_LastDigBlockZ(0),
	m_State(csConnected),
	m_NumExplosionsThisTick(0),
	m_NumBlockChangeInteractionsThisTick(0),
	m_UniqueID(0),
	m_HasSentPlayerChunk(false),
	m_Locale("en_GB"),
	m_LastPlacedSign(0, -1, 0),
	m_ProtocolVersion(0)
{
	s_ClientCount++;  // Not protected by CS because clients are always constructed from the same thread
	m_UniqueID = s_ClientCount;

	LOGD("New ClientHandle created at %p", static_cast<void *>(this));
}





cClientHandle::~cClientHandle()
{
	ASSERT(m_State == csDestroyed);  // Has Destroy() been called?

	LOGD("Deleting client \"%s\" at %p", GetUsername().c_str(), static_cast<void *>(this));

	LOGD("ClientHandle at %p deleted", static_cast<void *>(this));
}





void cClientHandle::Destroy(void)
{
	if (!SetState(csDestroyed))
	{
		// Already called
		LOGD("%s: client %p, \"%s\" already destroyed, bailing out", __FUNCTION__, static_cast<void *>(this), m_Username.c_str());
		return;
	}

	LOGD("%s: destroying client %p, \"%s\" @ %s", __FUNCTION__, static_cast<void *>(this), m_Username.c_str(), m_IPString.c_str());

	{
		cCSLock Lock(m_CSOutgoingData);
		m_Protocol.HandleOutgoingData(m_OutgoingData);  // Finalise any encryption.
		m_Link->Send(m_OutgoingData.data(), m_OutgoingData.size());  // Flush remaining data.
		m_Link->Shutdown();  // Cleanly close the connection.
		m_Link.reset();  // Release the strong reference cTCPLink holds to ourself.
	}
}





AString cClientHandle::FormatChatPrefix(
	bool ShouldAppendChatPrefixes, const AString & a_ChatPrefixS,
	const AString & m_Color1, const AString & m_Color2
)
{
	if (ShouldAppendChatPrefixes)
	{
		return Printf("%s[%s] %s", m_Color1.c_str(), a_ChatPrefixS.c_str(), m_Color2.c_str());
	}
	else
	{
		return Printf("%s", m_Color1.c_str());
	}
}





AString cClientHandle::FormatMessageType(bool ShouldAppendChatPrefixes, eMessageType a_ChatPrefix, const AString & a_AdditionalData)
{
	switch (a_ChatPrefix)
	{
		case mtCustom:      return "";
		case mtFailure:     return FormatChatPrefix(ShouldAppendChatPrefixes, "INFO",  cChatColor::Rose,   cChatColor::White);
		case mtInformation: return FormatChatPrefix(ShouldAppendChatPrefixes, "INFO",  cChatColor::Yellow, cChatColor::White);
		case mtSuccess:     return FormatChatPrefix(ShouldAppendChatPrefixes, "INFO",  cChatColor::Green,  cChatColor::White);
		case mtWarning:     return FormatChatPrefix(ShouldAppendChatPrefixes, "WARN",  cChatColor::Rose,   cChatColor::White);
		case mtFatal:       return FormatChatPrefix(ShouldAppendChatPrefixes, "FATAL", cChatColor::Red,    cChatColor::White);
		case mtDeath:       return FormatChatPrefix(ShouldAppendChatPrefixes, "DEATH", cChatColor::Gray,   cChatColor::White);
		case mtJoin:        return FormatChatPrefix(ShouldAppendChatPrefixes, "JOIN",  cChatColor::Yellow, cChatColor::White);
		case mtLeave:       return FormatChatPrefix(ShouldAppendChatPrefixes, "LEAVE", cChatColor::Yellow, cChatColor::White);
		case mtPrivateMessage:
		{
			if (ShouldAppendChatPrefixes)
			{
				return Printf("%s[MSG: %s] %s%s", cChatColor::LightBlue, a_AdditionalData.c_str(), cChatColor::White, cChatColor::Italic);
			}
			else
			{
				return Printf("%s: %s", a_AdditionalData.c_str(), cChatColor::LightBlue);
			}
		}
		case mtMaxPlusOne: break;
	}
	return "";
}





cUUID cClientHandle::GenerateOfflineUUID(const AString & a_Username)
{
	// Online UUIDs are always version 4 (random)
	// We use Version 3 (MD5 hash) UUIDs for the offline UUIDs
	// This guarantees that they will never collide with an online UUID and can be distinguished.
	// This is also consistent with the vanilla offline UUID scheme.

	return cUUID::GenerateVersion3("OfflinePlayer:" + a_Username);
}





bool cClientHandle::IsUUIDOnline(const cUUID & a_UUID)
{
	// Online UUIDs are always version 4 (random)
	// We use Version 3 (MD5 hash) UUIDs for the offline UUIDs
	// This guarantees that they will never collide with an online UUID and can be distinguished.
	return (a_UUID.Version() == 4);
}





void cClientHandle::ProcessProtocolOut()
{
	decltype(m_OutgoingData) OutgoingData;
	{
		cCSLock Lock(m_CSOutgoingData);

		// Bail out when there's nothing to send to avoid TCPLink::Send overhead:
		if (m_OutgoingData.empty())
		{
			return;
		}

		std::swap(OutgoingData, m_OutgoingData);
	}

	// Due to cTCPLink's design of holding a strong pointer to ourself, we need to explicitly reset m_Link.
	// This means we need to check it's not nullptr before trying to send, but also capture the link,
	// to prevent it being reset between the null check and the Send:
	if (auto Link = m_Link; Link != nullptr)
	{
		m_Protocol.HandleOutgoingData(OutgoingData);
		Link->Send(OutgoingData.data(), OutgoingData.size());
	}
}





void cClientHandle::Kick(const AString & a_Reason)
{
	if (m_State >= csAuthenticating)  // Don't log pings
	{
		LOGINFO("Kicking player %s for \"%s\"", m_Username.c_str(), StripColorCodes(a_Reason).c_str());
	}
	SendDisconnect(a_Reason);
}





void cClientHandle::Authenticate(const AString & a_Name, const cUUID & a_UUID, const Json::Value & a_Properties)
{
	{
		cCSLock lock(m_CSState);
		/*
		LOGD("Processing authentication for client %s @ %s (%p), state = %d",
			m_Username.c_str(), m_IPString.c_str(), static_cast<void *>(this), m_State.load()
		);
		//*/

		if (m_State != csAuthenticating)
		{
			return;
		}

		ASSERT(m_Player == nullptr);

		m_Username = a_Name;

		// Only assign UUID and properties if not already pre-assigned (BungeeCord sends those in the Handshake packet):
		if (m_UUID.IsNil())
		{
			m_UUID = a_UUID;
		}
		if (m_Properties.empty())
		{
			m_Properties = a_Properties;
		}

		// Send login success (if the protocol supports it):
		m_Protocol->SendLoginSuccess();

		if (m_ForgeHandshake.m_IsForgeClient)
		{
			m_ForgeHandshake.BeginForgeHandshake(a_Name, a_UUID, a_Properties);
		}
		else
		{
			FinishAuthenticate(a_Name, a_UUID, a_Properties);
		}
	}
}





void cClientHandle::FinishAuthenticate(const AString & a_Name, const cUUID & a_UUID, const Json::Value & a_Properties)
{
	// Serverside spawned player (so data are loaded).
	std::unique_ptr<cPlayer> Player;

	try
	{
		Player = std::make_unique<cPlayer>(shared_from_this());
	}
	catch (const std::exception & Oops)
	{
		LOGWARNING("Error reading player \"%s\": %s", GetUsername().c_str(), Oops.what());
		Kick("Contact an operator.\n\nYour player's save files could not be parsed.\nTo avoid data loss you are prevented from joining.");
		return;
	}

	m_Player = Player.get();

	/*
	LOGD("Created a new cPlayer object at %p for client %s @ %s (%p)",
		static_cast<void *>(m_Player),
		m_Username.c_str(), m_IPString.c_str(), static_cast<void *>(this)
	);
	//*/

	cWorld * World = cRoot::Get()->GetWorld(m_Player->GetLoadedWorldName());
	if (World == nullptr)
	{
		World = cRoot::Get()->GetDefaultWorld();
	}

	// Atomically increment player count (in server thread):
	cRoot::Get()->GetServer()->PlayerCreated();

	if (!cRoot::Get()->GetPluginManager()->CallHookPlayerJoined(*m_Player))
	{
		cRoot::Get()->BroadcastChatJoin(Printf("%s has joined the game", a_Name.c_str()));
		LOGINFO("Player %s has joined the game", a_Name.c_str());
	}

	// TODO: this accesses the world spawn from the authenticator thread
	// World spawn should be sent in OnAddedToWorld.
	// Return a server login packet:
	m_Protocol->SendLogin(*m_Player, *World);

	if (m_Player->GetKnownRecipes().empty())
	{
		SendInitRecipes(0);
	}
	else
	{
		for (const auto KnownRecipe : m_Player->GetKnownRecipes())
		{
			SendInitRecipes(KnownRecipe);
		}
	}

	// Send player list items:
	SendPlayerListAddPlayer(*m_Player);  // Add ourself
	cRoot::Get()->BroadcastPlayerListsAddPlayer(*m_Player);  // Add ourself to everyone else
	cRoot::Get()->SendPlayerLists(m_Player);  // Add everyone else to ourself

	// Send statistics:
	SendStatistics(m_Player->GetStatistics());

	// Delay the first ping until the client "settles down"
	// This should fix #889, "BadCast exception, cannot convert bit to fm" error in client
	m_PingStartTime = std::chrono::steady_clock::now() + std::chrono::seconds(3);  // Send the first KeepAlive packet in 3 seconds

	// Remove the client handle from the server, it will be ticked from its cPlayer object from now on:
	cRoot::Get()->GetServer()->ClientMovedToWorld(this);

	SetState(csDownloadingWorld);
	m_Player->Initialize(std::move(Player), *World);

	// LOGD("Client %s @ %s (%p) has been fully authenticated", m_Username.c_str(), m_IPString.c_str(), static_cast<void *>(this));
}





void cClientHandle::StreamNextChunks(void)
{
	ASSERT(m_Player != nullptr);

	int ChunkPosX = m_Player->GetChunkX();
	int ChunkPosZ = m_Player->GetChunkZ();

	if ((m_LastStreamedChunkX == ChunkPosX) && (m_LastStreamedChunkZ == ChunkPosZ))
	{
		// All chunks are already loaded and the player has not moved, work is done:
		return;
	}

	// Player moved chunks and / or loading is not finished, reset to bogus (GH #4531):
	m_LastStreamedChunkX = std::numeric_limits<decltype(m_LastStreamedChunkX)>::max();
	m_LastStreamedChunkZ = std::numeric_limits<decltype(m_LastStreamedChunkZ)>::max();

	int StreamedChunks = 0;
	Vector3d Position = m_Player->GetEyePosition();
	Vector3d LookVector = m_Player->GetLookVector();

	// Get the look vector and normalize it.
	LookVector.Normalize();

	// High priority: Load the chunks that are in the view-direction of the player (with a radius of 3)
	for (int Range = 0; Range < m_CurrentViewDistance; Range++)
	{
		Vector3d Vector = Position + LookVector * cChunkDef::Width * Range;

		// Get the chunk from the x / z coords.
		int RangeX, RangeZ = 0;
		cChunkDef::BlockToChunk(FloorC(Vector.x), FloorC(Vector.z), RangeX, RangeZ);

		for (int X = 0; X < 7; X++)
		{
			for (int Z = 0; Z < 7; Z++)
			{
				int ChunkX = RangeX + ((X >= 4) ? (3 - X) : X);
				int ChunkZ = RangeZ + ((Z >= 4) ? (3 - Z) : Z);
				cChunkCoords Coords(ChunkX, ChunkZ);

				// Checks if the chunk is in distance
				if ((Diff(ChunkX, ChunkPosX) > m_CurrentViewDistance) || (Diff(ChunkZ, ChunkPosZ) > m_CurrentViewDistance))
				{
					continue;
				}

				// If the chunk already loading / loaded -> skip
				{
					cCSLock Lock(m_CSChunkLists);
					if (
						(m_ChunksToSend.find(Coords) != m_ChunksToSend.end()) ||
						(m_LoadedChunks.find(Coords) != m_LoadedChunks.end())
					)
					{
						continue;
					}
				}

				// Unloaded chunk found -> Send it to the client.
				StreamChunk(ChunkX, ChunkZ, ((Range <= 2) ? cChunkSender::Priority::Critical : cChunkSender::Priority::Medium));

				if (++StreamedChunks == MAX_CHUNKS_STREAMED_PER_TICK)
				{
					return;
				}
			}
		}
	}

	// Low priority: Add all chunks that are in range. (From the center out to the edge)
	for (int d = 0; d <= m_CurrentViewDistance; ++d)  // cycle through (square) distance, from nearest to furthest
	{
		const auto StreamIfUnloaded = [this](const cChunkCoords Chunk)
		{
			// If the chunk already loading / loaded -> skip
			{
				cCSLock Lock(m_CSChunkLists);
				if (
					(m_ChunksToSend.find(Chunk) != m_ChunksToSend.end()) ||
					(m_LoadedChunks.find(Chunk) != m_LoadedChunks.end())
				)
				{
					return false;
				}
			}

			// Unloaded chunk found -> Send it to the client.
			StreamChunk(Chunk.m_ChunkX, Chunk.m_ChunkZ, cChunkSender::Priority::Low);
			return true;
		};

		// For each distance, send the first unloaded chunk in a hollow square centered around current position:
		for (int i = -d; i <= d; ++i)
		{
			if (StreamIfUnloaded({ ChunkPosX + d, ChunkPosZ + i }) || StreamIfUnloaded({ ChunkPosX - d, ChunkPosZ + i }))
			{
				if (++StreamedChunks == MAX_CHUNKS_STREAMED_PER_TICK)
				{
					return;
				}
			}
		}
		for (int i = -d + 1; i < d; ++i)
		{
			if (StreamIfUnloaded({ ChunkPosX + i, ChunkPosZ + d }) || StreamIfUnloaded({ ChunkPosX + i, ChunkPosZ - d }))
			{
				if (++StreamedChunks == MAX_CHUNKS_STREAMED_PER_TICK)
				{
					return;
				}
			}
		}
	}

	// All chunks are loaded -> Sets the last loaded chunk coordinates to current coordinates
	m_LastStreamedChunkX = ChunkPosX;
	m_LastStreamedChunkZ = ChunkPosZ;
}





void cClientHandle::UnloadOutOfRangeChunks(void)
{
	int ChunkPosX = FAST_FLOOR_DIV(static_cast<int>(m_Player->GetPosX()), cChunkDef::Width);
	int ChunkPosZ = FAST_FLOOR_DIV(static_cast<int>(m_Player->GetPosZ()), cChunkDef::Width);

	cChunkCoordsList ChunksToRemove;
	{
		cCSLock Lock(m_CSChunkLists);
		for (auto itr = m_LoadedChunks.begin(); itr != m_LoadedChunks.end();)
		{
			const auto DiffX = Diff((*itr).m_ChunkX, ChunkPosX);
			const auto DiffZ = Diff((*itr).m_ChunkZ, ChunkPosZ);
			if ((DiffX > m_CurrentViewDistance) || (DiffZ > m_CurrentViewDistance))
			{
				ChunksToRemove.push_back(*itr);
				itr = m_LoadedChunks.erase(itr);
			}
			else
			{
				++itr;
			}
		}

		for (auto itr = m_ChunksToSend.begin(); itr != m_ChunksToSend.end();)
		{
			const auto DiffX = Diff((*itr).m_ChunkX, ChunkPosX);
			const auto DiffZ = Diff((*itr).m_ChunkZ, ChunkPosZ);
			if ((DiffX > m_CurrentViewDistance) || (DiffZ > m_CurrentViewDistance))
			{
				itr = m_ChunksToSend.erase(itr);
			}
			else
			{
				++itr;
			}
		}
	}

	for (cChunkCoordsList::iterator itr = ChunksToRemove.begin(); itr != ChunksToRemove.end(); ++itr)
	{
		m_Player->GetWorld()->RemoveChunkClient(itr->m_ChunkX, itr->m_ChunkZ, this);
		SendUnloadChunk(itr->m_ChunkX, itr->m_ChunkZ);
	}

	m_LastUnloadCheck = m_Player->GetWorld()->GetWorldAge();
}





void cClientHandle::StreamChunk(int a_ChunkX, int a_ChunkZ, cChunkSender::Priority a_Priority)
{
	cWorld * World = m_Player->GetWorld();
	ASSERT(World != nullptr);

	if (World->AddChunkClient(a_ChunkX, a_ChunkZ, this))
	{
		{
			cCSLock Lock(m_CSChunkLists);
			m_LoadedChunks.emplace(a_ChunkX, a_ChunkZ);
			m_ChunksToSend.emplace(a_ChunkX, a_ChunkZ);
		}
		World->SendChunkTo(a_ChunkX, a_ChunkZ, a_Priority, this);
	}
}





void cClientHandle::HandleAnimation(const bool a_SwingMainHand)
{
	if (cPluginManager::Get()->CallHookPlayerAnimation(*m_Player, a_SwingMainHand ? 0 : 1))
	{
		// Plugin disagrees, bail out:
		return;
	}

	m_Player->GetWorld()->BroadcastEntityAnimation(*m_Player, a_SwingMainHand ? EntityAnimation::PlayerMainHandSwings : EntityAnimation::PlayerOffHandSwings, this);
}





void cClientHandle::HandleNPCTrade(int a_SlotNum)
{
	// TODO
	LOGWARNING("%s: Not implemented yet", __FUNCTION__);
}





void cClientHandle::HandleOpenHorseInventory()
{
	m_Player->OpenHorseInventory();
}





void cClientHandle::HandlePing(void)
{
	/* TODO: unused function, handles Legacy Server List Ping
	http://wiki.vg/Protocol#Legacy_Server_List_Ping suggests that servers SHOULD handle this packet */

	// Somebody tries to retrieve information about the server
	AString Reply;
	const cServer & Server = *cRoot::Get()->GetServer();

	Printf(Reply, "%s%s%zu%s%zu",
		Server.GetDescription().c_str(),
		cChatColor::Delimiter,
		Server.GetNumPlayers(),
		cChatColor::Delimiter,
		Server.GetMaxPlayers()
	);
	Kick(Reply);
}





bool cClientHandle::HandleLogin()
{
	{
		cCSLock lock(m_CSState);
		if (m_State != csConnected)
		{
			/*
			LOGD("Client %s @ %s (%p, state %d) has disconnected before logging in, bailing out of login",
				a_Username.c_str(), m_IPString.c_str(), static_cast<void *>(this), m_State.load()
			);
			//*/
			return false;
		}

		// LOGD("Handling login for client %s @ %s (%p), state = %d", a_Username.c_str(), m_IPString.c_str(), static_cast<void *>(this), m_State.load());

		// Let the plugins know about this event, they may refuse the player:
		if (cRoot::Get()->GetPluginManager()->CallHookLogin(*this, m_ProtocolVersion, GetUsername()))
		{
			SendDisconnect("Login Rejected!");
			return false;
		}

		m_State = csAuthenticating;
	}  // lock(m_CSState)

	// Schedule for authentication; until then, let the player wait (but do not block)
	cRoot::Get()->GetAuthenticator().Authenticate(GetUniqueID(), GetUsername(), m_Protocol->GetAuthServerID());
	return true;
}





void cClientHandle::HandleCreativeInventory(Int16 a_SlotNum, const cItem & a_HeldItem, eClickAction a_ClickAction)
{
	// This is for creative Inventory changes
	if (!m_Player->IsGameModeCreative())
	{
		LOGWARNING("Got a CreativeInventoryAction packet from user \"%s\" while not in creative mode. Ignoring.", m_Username.c_str());
		return;
	}
	if (m_Player->GetWindow()->GetWindowType() != cWindow::wtInventory)
	{
		LOGWARNING("Got a CreativeInventoryAction packet from user \"%s\" while not in the inventory window. Ignoring.", m_Username.c_str());
		return;
	}

	m_Player->GetWindow()->Clicked(*m_Player, 0, a_SlotNum, a_ClickAction, a_HeldItem);
}





void cClientHandle::HandleCrouch(const bool a_IsCrouching)
{
	m_Player->SetCrouch(a_IsCrouching);
}





void cClientHandle::HandleEnchantItem(UInt8 a_WindowID, UInt8 a_Enchantment)
{
	if (a_Enchantment > 2)
	{
		LOGWARNING("%s attempt to crash the server with invalid enchanting selection (%u)!", GetUsername().c_str(), a_Enchantment);
		Kick("Selected invalid enchantment - hacked client?");
		return;
	}

	// Bail out if something's wrong with the window:
	if (
		(m_Player->GetWindow() == nullptr) ||
		(m_Player->GetWindow()->GetWindowID() != a_WindowID) ||
		(m_Player->GetWindow()->GetWindowType() != cWindow::wtEnchantment)
	)
	{
		Kick("Enchantment with invalid window - hacked client?");
		return;
	}

	cEnchantingWindow * Window = static_cast<cEnchantingWindow *>(m_Player->GetWindow());
	const auto BaseEnchantmentLevel = Window->GetProperty(a_Enchantment);

	// Survival players must be checked they can afford enchantment and have lapis removed:
	if (!m_Player->IsGameModeCreative())
	{
		const auto XpRequired = m_Player->XpForLevel(BaseEnchantmentLevel);
		auto LapisStack = *Window->m_SlotArea->GetSlot(1, *m_Player);  // A copy of the lapis stack.
		const auto LapisRequired = a_Enchantment + 1;

		// Only allow enchantment if the player has sufficient levels and lapis to enchant:
		if ((m_Player->GetCurrentXp() >= XpRequired) && (LapisStack.m_ItemCount >= LapisRequired))
		{
			/** We need to reduce the player's level by the number of lapis required.
			However we need to keep the resulting percentage filled the same. */

			const auto TargetLevel = m_Player->GetXpLevel() - LapisRequired;
			const auto CurrentFillPercent = m_Player->GetXpPercentage();

			// The experience to remove in order to reach the start (0% fill) of the target level.
			const auto DeltaForLevel = -m_Player->GetCurrentXp() + m_Player->XpForLevel(TargetLevel);

			// The experience to add to get the same fill percent.
			const auto DeltaForPercent = CurrentFillPercent * (m_Player->XpForLevel(TargetLevel + 1) - m_Player->XpForLevel(TargetLevel));

			// Apply the experience delta, rounded for greater accuracy:
			m_Player->DeltaExperience(static_cast<int>(std::lround(DeltaForLevel + DeltaForPercent)));

			// Now reduce the lapis in our stack and send it back:
			LapisStack.AddCount(static_cast<char>(-LapisRequired));
			Window->m_SlotArea->SetSlot(1, *m_Player, LapisStack);
		}
		else
		{
			// Not creative and can't afford enchantment, so exit:
			Kick("Selected unavailable enchantment - hacked client?");
			return;
		}
	}

	// Retrieve the enchanted item corresponding to our chosen option (top, middle, bottom)
	cItem EnchantedItem = Window->m_SlotArea->SelectEnchantedOption(a_Enchantment);

	// Set the item slot to our new enchanted item:
	Window->m_SlotArea->SetSlot(0, *m_Player, EnchantedItem);
	m_Player->PermuteEnchantmentSeed();
}





void cClientHandle::HandlePlayerAbilities(bool a_IsFlying, float FlyingSpeed, float WalkingSpeed)
{
	UNUSED(FlyingSpeed);  // Ignore the client values for these
	UNUSED(WalkingSpeed);

	m_Player->SetFlying(a_IsFlying);
}





void cClientHandle::HandlePluginMessage(const AString & a_Channel, const ContiguousByteBufferView a_Message)
{
	if (a_Channel == "REGISTER")
	{
		if (HasPluginChannel(a_Channel))
		{
			SendPluginMessage("UNREGISTER", a_Channel);
			return;  // Can't register again if already taken - kinda defeats the point of plugin messaging!
		}

		RegisterPluginChannels(BreakApartPluginChannels(a_Message));
	}
	else if (a_Channel == "UNREGISTER")
	{
		UnregisterPluginChannels(BreakApartPluginChannels(a_Message));
	}
	else if (a_Channel == "FML|HS")
	{
		m_ForgeHandshake.DataReceived(this, a_Message);
	}
	else if (!HasPluginChannel(a_Channel))
	{
		// Ignore if client sent something but didn't register the channel first
		LOGD("Player %s sent a plugin message on channel \"%s\", but didn't REGISTER it first", GetUsername().c_str(), a_Channel.c_str());
		SendPluginMessage("UNREGISTER", a_Channel);
		return;
	}

	cPluginManager::Get()->CallHookPluginMessage(*this, a_Channel, a_Message);
}





AStringVector cClientHandle::BreakApartPluginChannels(const ContiguousByteBufferView a_PluginChannels)
{
	// Break the string on each NUL character.
	// Note that StringSplit() doesn't work on this because NUL is a special char - string terminator
	size_t len = a_PluginChannels.size();
	size_t first = 0;
	AStringVector res;
	for (size_t i = 0; i < len; i++)
	{
		if (a_PluginChannels[i] != std::byte(0))
		{
			continue;
		}
		if (i > first)
		{
			const auto Part = a_PluginChannels.substr(first, i - first);
			res.emplace_back(reinterpret_cast<const char *>(Part.data()), Part.size());
		}
		first = i + 1;
	}  // for i - a_PluginChannels[]
	if (first < len)
	{
		const auto Part = a_PluginChannels.substr(first, len - first);
		res.emplace_back(reinterpret_cast<const char *>(Part.data()), Part.size());
	}
	return res;
}





void cClientHandle::RegisterPluginChannels(const AStringVector & a_ChannelList)
{
	for (AStringVector::const_iterator itr = a_ChannelList.begin(), end = a_ChannelList.end(); itr != end; ++itr)
	{
		m_PluginChannels.insert(*itr);
	}  // for itr - a_ChannelList[]
}





void cClientHandle::UnregisterPluginChannels(const AStringVector & a_ChannelList)
{
	for (AStringVector::const_iterator itr = a_ChannelList.begin(), end = a_ChannelList.end(); itr != end; ++itr)
	{
		m_PluginChannels.erase(*itr);
	}  // for itr - a_ChannelList[]
}





void cClientHandle::HandleBeaconSelection(unsigned a_PrimaryEffect, unsigned a_SecondaryEffect)
{
	cWindow * Window = m_Player->GetWindow();
	if ((Window == nullptr) || (Window->GetWindowType() != cWindow::wtBeacon))
	{
		return;
	}
	cBeaconWindow * BeaconWindow = static_cast<cBeaconWindow *>(Window);

	if (Window->GetSlot(*m_Player, 0)->IsEmpty())
	{
		return;
	}

	cEntityEffect::eType PrimaryEffect = cEntityEffect::effNoEffect;
	if (a_PrimaryEffect <= static_cast<int>(cEntityEffect::effSaturation))
	{
		PrimaryEffect = static_cast<cEntityEffect::eType>(a_PrimaryEffect);
	}
	cEntityEffect::eType SecondaryEffect = cEntityEffect::effNoEffect;
	if (a_SecondaryEffect <= static_cast<int>(cEntityEffect::effSaturation))
	{
		SecondaryEffect = static_cast<cEntityEffect::eType>(a_SecondaryEffect);
	}

	Window->SetSlot(*m_Player, 0, cItem());
	BeaconWindow->GetBeaconEntity()->SetPrimaryEffect(PrimaryEffect);

	// Valid effect check. Vanilla don't check this, but we do it :)
	if (
		(SecondaryEffect == cEntityEffect::effNoEffect) ||
		(SecondaryEffect == cEntityEffect::effRegeneration) ||
		(SecondaryEffect == BeaconWindow->GetBeaconEntity()->GetPrimaryEffect())
	)
	{
		BeaconWindow->GetBeaconEntity()->SetSecondaryEffect(SecondaryEffect);
	}
	else
	{
		BeaconWindow->GetBeaconEntity()->SetSecondaryEffect(cEntityEffect::effNoEffect);
	}

	m_Player->CloseWindow(true);
}





void cClientHandle::HandleCommandBlockBlockChange(int a_BlockX, int a_BlockY, int a_BlockZ, const AString & a_NewCommand)
{
	if (a_NewCommand.empty())
	{
		Kick("Command block string unexpectedly empty - hacked client?");
		return;
	}
	if ((m_Player == nullptr) || !m_Player->HasPermission("comandblock.set"))
	{
		SendChat("You cannot edit command blocks on this server", mtFailure);
		return;
	}

	cWorld * World = m_Player->GetWorld();
	if (World->AreCommandBlocksEnabled())
	{
		World->SetCommandBlockCommand(a_BlockX, a_BlockY, a_BlockZ, a_NewCommand);
		SendChat("Successfully set command block command", mtSuccess);
	}
	else
	{
		SendChat("Command blocks are not enabled on this server", mtFailure);
	}
}





void cClientHandle::HandleCommandBlockEntityChange(UInt32 a_EntityID, const AString & a_NewCommand)
{
	// TODO
	LOGWARNING("%s: Not implemented yet", __FUNCTION__);
}





void cClientHandle::HandleAnvilItemName(const AString & a_ItemName)
{
	if ((m_Player->GetWindow() == nullptr) || (m_Player->GetWindow()->GetWindowType() != cWindow::wtAnvil))
	{
		return;
	}

	if (a_ItemName.length() <= 30)
	{
		static_cast<cAnvilWindow *>(m_Player->GetWindow())->SetRepairedItemName(a_ItemName, m_Player);
	}
}





void cClientHandle::HandleLeftClick(int a_BlockX, int a_BlockY, int a_BlockZ, eBlockFace a_BlockFace, UInt8 a_Status)
{
	FLOGD("HandleLeftClick: {0}; Face: {1}; Stat: {2}",
		Vector3i{a_BlockX, a_BlockY, a_BlockZ}, a_BlockFace, a_Status
	);

	m_NumBlockChangeInteractionsThisTick++;

	if (!CheckBlockInteractionsRate())
	{
		Kick("Too many blocks were destroyed per unit time - hacked client?");
		return;
	}

	if ((a_Status == DIG_STATUS_STARTED) || (a_Status == DIG_STATUS_FINISHED))
	{
		if (a_BlockFace == BLOCK_FACE_NONE)
		{
			return;
		}

		/* Check for clickthrough-blocks:
		When the user breaks a fire block, the client send the wrong block location.
		We must find the right block with the face direction. */

		int BlockX = a_BlockX;
		int BlockY = a_BlockY;
		int BlockZ = a_BlockZ;
		AddFaceDirection(BlockX, BlockY, BlockZ, a_BlockFace);

		if (cChunkDef::IsValidHeight(BlockY) && cBlockInfo::IsClickedThrough(m_Player->GetWorld()->GetBlock({ BlockX, BlockY, BlockZ })))
		{
			a_BlockX = BlockX;
			a_BlockY = BlockY;
			a_BlockZ = BlockZ;
		}

		if (
			((Diff(m_Player->GetPosX(), static_cast<double>(a_BlockX)) > 6) ||
			(Diff(m_Player->GetPosY(), static_cast<double>(a_BlockY)) > 6) ||
			(Diff(m_Player->GetPosZ(), static_cast<double>(a_BlockZ)) > 6))
		)
		{
			m_Player->GetWorld()->SendBlockTo(a_BlockX, a_BlockY, a_BlockZ, *m_Player);
			return;
		}
	}

	cPluginManager * PlgMgr = cRoot::Get()->GetPluginManager();
	if (m_Player->IsFrozen() || PlgMgr->CallHookPlayerLeftClick(*m_Player, a_BlockX, a_BlockY, a_BlockZ, a_BlockFace, static_cast<char>(a_Status)))
	{
		// A plugin doesn't agree with the action, replace the block on the client and quit:
		m_Player->GetWorld()->SendBlockTo(a_BlockX, a_BlockY, a_BlockZ, *m_Player);
		SendPlayerPosition();  // Prevents the player from falling through the block that was temporarily broken client side.
		return;
	}

	switch (a_Status)
	{
		case DIG_STATUS_DROP_HELD:  // Drop held item
		{
			if (PlgMgr->CallHookPlayerTossingItem(*m_Player))
			{
				// A plugin doesn't agree with the tossing. The plugin itself is responsible for handling the consequences (possible inventory mismatch)
				return;
			}

			m_Player->TossEquippedItem();
			return;
		}

		case DIG_STATUS_SHOOT_EAT:
		{
			cItemHandler * ItemHandler = cItemHandler::GetItemHandler(m_Player->GetEquippedItem());
			if (ItemHandler->IsFood() || ItemHandler->IsDrinkable(m_Player->GetEquippedItem().m_ItemDamage))
			{
				m_Player->AbortEating();
				return;
			}
			else
			{
				if (PlgMgr->CallHookPlayerShooting(*m_Player))
				{
					// A plugin doesn't agree with the action. The plugin itself is responsible for handling the consequences (possible inventory mismatch)
					return;
				}
				// When bow is in off-hand / shield slot
				if (m_Player->GetInventory().GetShieldSlot().m_ItemType == E_ITEM_BOW)
				{
					ItemHandler = cItemHandler::GetItemHandler(m_Player->GetInventory().GetShieldSlot());
				}
				ItemHandler->OnItemShoot(m_Player, {a_BlockX, a_BlockY, a_BlockZ}, a_BlockFace);
			}
			return;
		}

		case DIG_STATUS_STARTED:
		{
			HandleBlockDigStarted(a_BlockX, a_BlockY, a_BlockZ, a_BlockFace);
			return;
		}

		case DIG_STATUS_FINISHED:
		{
			HandleBlockDigFinished(a_BlockX, a_BlockY, a_BlockZ, a_BlockFace);
			return;
		}

		case DIG_STATUS_CANCELLED:
		{
			// Block breaking cancelled by player
			FinishDigAnimation();
			return;
		}

		case DIG_STATUS_DROP_STACK:
		{
			if (PlgMgr->CallHookPlayerTossingItem(*m_Player))
			{
				// A plugin doesn't agree with the tossing. The plugin itself is responsible for handling the consequences (possible inventory mismatch)
				return;
			}
			m_Player->TossEquippedItem(64);  // Toss entire slot - if there aren't enough items, the maximum will be ejected
			return;
		}

		case DIG_STATUS_SWAP_ITEM_IN_HAND:
		{

			cItem EquippedItem = m_Player->GetEquippedItem();
			cItem OffhandItem = m_Player->GetOffHandEquipedItem();

			cInventory & Inventory = m_Player->GetInventory();
			Inventory.SetShieldSlot(EquippedItem);
			Inventory.SetEquippedItem(OffhandItem);

			return;
		}

		default:
		{
			ASSERT(!"Unhandled DIG_STATUS");
			return;
		}
	}  // switch (a_Status)
}





void cClientHandle::HandleBlockDigStarted(int a_BlockX, int a_BlockY, int a_BlockZ, eBlockFace a_BlockFace)
{
	if (m_Player->IsGameModeAdventure())
	{
		// Players in adventure mode can't destroy blocks
		return;
	}

	if (
		m_HasStartedDigging &&
		(a_BlockX == m_LastDigBlockX) &&
		(a_BlockY == m_LastDigBlockY) &&
		(a_BlockZ == m_LastDigBlockZ)
	)
	{
		// It is a duplicate packet, drop it right away
		return;
	}

	BLOCKTYPE DiggingBlock;
	NIBBLETYPE DiggingMeta;
	m_Player->GetWorld()->GetBlockTypeMeta({ a_BlockX, a_BlockY, a_BlockZ }, DiggingBlock, DiggingMeta);

	if (
		m_Player->IsGameModeCreative() &&
		ItemCategory::IsSword(m_Player->GetInventory().GetEquippedItem().m_ItemType) &&
		(DiggingBlock != E_BLOCK_FIRE)
	)
	{
		// Players can't destroy blocks with a sword in the hand.
		return;
	}

	if (
		(Diff(m_Player->GetPosX(), static_cast<double>(a_BlockX)) > 6) ||
		(Diff(m_Player->GetPosY(), static_cast<double>(a_BlockY)) > 6) ||
		(Diff(m_Player->GetPosZ(), static_cast<double>(a_BlockZ)) > 6)
	)
	{
		m_Player->GetWorld()->SendBlockTo(a_BlockX, a_BlockY, a_BlockZ, *m_Player);
		return;
	}

	// Set the last digging coords to the block being dug, so that they can be checked in DIG_FINISHED to avoid dig / aim bug in the client:
	m_HasStartedDigging = true;
	m_LastDigBlockX = a_BlockX;
	m_LastDigBlockY = a_BlockY;
	m_LastDigBlockZ = a_BlockZ;

	if (
		m_Player->IsGameModeCreative() ||         // In creative mode, digging is done immediately
		m_Player->CanInstantlyMine(DiggingBlock)  // Sometimes the player is fast enough to instantly mine
	)
	{
		// Immediately done:
		m_BreakProgress = 1;

		HandleBlockDigFinished(a_BlockX, a_BlockY, a_BlockZ, a_BlockFace);
		return;
	}

	m_BreakProgress = 0;

	// Start dig animation
	// TODO: calculate real animation speed
	// TODO: Send animation packets even without receiving any other packets
	m_BlockDigAnimSpeed = 10;
	m_BlockDigAnimX = a_BlockX;
	m_BlockDigAnimY = a_BlockY;
	m_BlockDigAnimZ = a_BlockZ;
	m_BlockDigAnimStage = 0;
	m_Player->GetWorld()->BroadcastBlockBreakAnimation(static_cast<UInt32>(m_UniqueID), {m_BlockDigAnimX, m_BlockDigAnimY, m_BlockDigAnimZ}, 0, this);

	cWorld * World = m_Player->GetWorld();
	cChunkInterface ChunkInterface(World->GetChunkMap());
	cBlockHandler::For(DiggingBlock).OnDigging(ChunkInterface, *World, *m_Player, {a_BlockX, a_BlockY, a_BlockZ});

	cItemHandler * ItemHandler = cItemHandler::GetItemHandler(m_Player->GetEquippedItem());
	ItemHandler->OnDiggingBlock(World, m_Player, m_Player->GetEquippedItem(), {a_BlockX, a_BlockY, a_BlockZ}, a_BlockFace);
}





void cClientHandle::HandleBlockDigFinished(int a_BlockX, int a_BlockY, int a_BlockZ, eBlockFace a_BlockFace)
{
	if (
		!m_HasStartedDigging ||           // Hasn't received the DIG_STARTED packet
		(m_LastDigBlockX != a_BlockX) ||  // DIG_STARTED has had different pos
		(m_LastDigBlockY != a_BlockY) ||
		(m_LastDigBlockZ != a_BlockZ)
	)
	{
		FLOGD("Prevented a dig / aim bug in the client (finish {0} vs start {1}, HSD: {2})",
			Vector3i{a_BlockX, a_BlockY, a_BlockZ},
			Vector3i{m_LastDigBlockX, m_LastDigBlockY, m_LastDigBlockZ},
			(m_HasStartedDigging ? "True" : "False")
		);
		return;
	}

	FinishDigAnimation();

	BLOCKTYPE DugBlock;
	NIBBLETYPE DugMeta;
	m_Player->GetWorld()->GetBlockTypeMeta({ a_BlockX, a_BlockY, a_BlockZ }, DugBlock, DugMeta);

	if (!m_Player->IsGameModeCreative())
	{
		m_BreakProgress += m_Player->GetMiningProgressPerTick(DugBlock);

		// Check for very fast tools. Maybe instead of FASTBREAK_PERCENTAGE we should check we are within x multiplied by the progress per tick
		if (m_BreakProgress < FASTBREAK_PERCENTAGE)
		{
			LOGD("Break progress of player %s was less than expected: %f < %f\n", m_Player->GetName().c_str(), m_BreakProgress * 100, FASTBREAK_PERCENTAGE * 100);
			// AntiFastBreak doesn't agree with the breaking. Bail out. Send the block back to the client, so that it knows:
			m_Player->GetWorld()->SendBlockTo(a_BlockX, a_BlockY, a_BlockZ, *m_Player);
			m_Player->GetWorld()->SendBlockTo(a_BlockX, a_BlockY + 1, a_BlockZ, *m_Player);  // Strange bug with doors
			SendPlayerPosition();  // Prevents the player from falling through the block that was temporarily broken client side.
			m_Player->SendMessage("FastBreak?");  // TODO Anticheat hook
			return;
		}
	}

	cWorld * World = m_Player->GetWorld();

	if (cRoot::Get()->GetPluginManager()->CallHookPlayerBreakingBlock(*m_Player, a_BlockX, a_BlockY, a_BlockZ, a_BlockFace, DugBlock, DugMeta))
	{
		// A plugin doesn't agree with the breaking. Bail out. Send the block back to the client, so that it knows:
		m_Player->GetWorld()->SendBlockTo(a_BlockX, a_BlockY, a_BlockZ, *m_Player);
		m_Player->GetWorld()->SendBlockTo(a_BlockX, a_BlockY + 1, a_BlockZ, *m_Player);  // Strange bug with doors
		SendPlayerPosition();  // Prevents the player from falling through the block that was temporarily broken client side.
		return;
	}

	if (DugBlock == E_BLOCK_AIR)
	{
		return;
	}

	// Apply hunger:
	m_Player->AddFoodExhaustion(0.025);

	// Damage the tool, but not for 0 hardness blocks:
	m_Player->UseEquippedItem(cBlockInfo::IsOneHitDig(DugBlock) ? cItemHandler::dlaBreakBlockInstant : cItemHandler::dlaBreakBlock);

	cChunkInterface ChunkInterface(World->GetChunkMap());
	Vector3i absPos(a_BlockX, a_BlockY, a_BlockZ);
	if (m_Player->IsGameModeSurvival())
	{
		World->DropBlockAsPickups(absPos, m_Player, &m_Player->GetEquippedItem());
	}
	else
	{
		World->DigBlock(absPos, m_Player);
	}

	World->BroadcastSoundParticleEffect(EffectID::PARTICLE_BLOCK_BREAK, absPos, DugBlock, this);
	cRoot::Get()->GetPluginManager()->CallHookPlayerBrokenBlock(*m_Player, a_BlockX, a_BlockY, a_BlockZ, a_BlockFace, DugBlock, DugMeta);
}





void cClientHandle::FinishDigAnimation()
{
	if (!m_HasStartedDigging)  // Hasn't received the DIG_STARTED packet
	{
		return;
	}

	m_HasStartedDigging = false;
	if (m_BlockDigAnimStage != -1)
	{
		// End dig animation
		m_BlockDigAnimStage = -1;
		// It seems that 10 ends block animation
		m_Player->GetWorld()->BroadcastBlockBreakAnimation(static_cast<UInt32>(m_UniqueID), {m_LastDigBlockX, m_LastDigBlockY, m_LastDigBlockZ}, 10, this);
	}

	m_BlockDigAnimX = -1;
	m_BlockDigAnimY = -1;
	m_BlockDigAnimZ = -1;
}





void cClientHandle::HandleRightClick(int a_BlockX, int a_BlockY, int a_BlockZ, eBlockFace a_BlockFace, int a_CursorX, int a_CursorY, int a_CursorZ, bool a_UsedMainHand)
{
	// This function handles three actions:
	// (1) Place a block;
	// (2) "Use" a block: Interactive with the block, like opening a chest/crafting table/furnace;
	// (3) Use the held item targeting a block. E.g. farming.
	//
	// Sneaking player will not use the block if hand is not empty.
	// Frozen player can do nothing.
	// In Game Mode Spectator, player cannot use item or place block, but can interactive with some block depending on cBlockInfo::IsUseableBySpectator(BlockType)
	//
	// If the action failed, we need to send an update of the placed block or inventory to the client.
	//
	// Actions rejected by plugin will not lead to other attempts.
	// E.g., when opening a chest with a dirt in hand, if the plugin rejects opening the chest, the dirt will not be placed.

	// TODO: We are still consuming the items in main hand. Remove this override when the off-hand consumption is handled correctly.
	a_UsedMainHand = true;
	const cItem & HeldItem = a_UsedMainHand ? m_Player->GetEquippedItem() : m_Player->GetInventory().GetShieldSlot();
	cItemHandler * ItemHandler = cItemHandler::GetItemHandler(HeldItem.m_ItemType);

	// TODO: This distance should be calculated from the point that the cursor pointing at, instead of the center of the block
	// Distance from the block's center to the player's eye height
	auto ClickedBlockPos = Vector3i(a_BlockX, a_BlockY, a_BlockZ);
	auto CursorPos = Vector3i(a_CursorX, a_CursorY, a_CursorZ);
	double Dist = (Vector3d(ClickedBlockPos) + Vector3d(0.5, 0.5, 0.5) - m_Player->GetEyePosition()).Length();
	FLOGD("HandleRightClick: {0}, face {1}, Cursor {2}, Hand: {3}, HeldItem: {4}; Dist: {5:.02f}",
		ClickedBlockPos, a_BlockFace, CursorPos, a_UsedMainHand, ItemToFullString(HeldItem), Dist
	);

	// Check the reach distance:
	// _X 2014-11-25: I've maxed at 5.26 with a Survival client and 5.78 with a Creative client in my tests
	double MaxDist = m_Player->IsGameModeCreative() ? 5.78 : 5.26;
	bool IsWithinReach = (Dist <= MaxDist);
	cWorld * World = m_Player->GetWorld();
	cPluginManager * PlgMgr = cRoot::Get()->GetPluginManager();

	if (
		!PlgMgr->CallHookPlayerRightClick(*m_Player, a_BlockX, a_BlockY, a_BlockZ, a_BlockFace, a_CursorX, a_CursorY, a_CursorZ) &&
		IsWithinReach && !m_Player->IsFrozen()
	)
	{
		BLOCKTYPE BlockType;
		NIBBLETYPE BlockMeta;
		World->GetBlockTypeMeta(ClickedBlockPos, BlockType, BlockMeta);
		const auto & BlockHandler = cBlockHandler::For(BlockType);

		bool Placeable = ItemHandler->IsPlaceable() && !m_Player->IsGameModeAdventure() && !m_Player->IsGameModeSpectator();
		bool BlockUsable = BlockHandler.IsUseable() && (!m_Player->IsGameModeSpectator() || cBlockInfo::IsUseableBySpectator(BlockType));

		if (BlockUsable && !(m_Player->IsCrouched() && !HeldItem.IsEmpty()))
		{
			cChunkInterface ChunkInterface(World->GetChunkMap());
			if (!PlgMgr->CallHookPlayerUsingBlock(*m_Player, a_BlockX, a_BlockY, a_BlockZ, a_BlockFace, a_CursorX, a_CursorY, a_CursorZ, BlockType, BlockMeta))
			{
				// Use a block:
				if (BlockHandler.OnUse(ChunkInterface, *World, *m_Player, ClickedBlockPos, a_BlockFace, CursorPos))
				{
					PlgMgr->CallHookPlayerUsedBlock(*m_Player, a_BlockX, a_BlockY, a_BlockZ, a_BlockFace, a_CursorX, a_CursorY, a_CursorZ, BlockType, BlockMeta);
					return;  // Block use was successful, we're done.
				}

				// Check if the item is place able, for example a torch on a fence:
				if (Placeable)
				{
					// Place a block:
					ItemHandler->OnPlayerPlace(*m_Player, HeldItem, {a_BlockX, a_BlockY, a_BlockZ}, a_BlockFace, {a_CursorX, a_CursorY, a_CursorZ});
				}

				return;
			}
		}
		else if (Placeable)
		{
			// TODO: Double check that we don't need this for using item and for packet out of range
			m_NumBlockChangeInteractionsThisTick++;
			if (!CheckBlockInteractionsRate())
			{
				Kick("Too many blocks were placed / interacted with per unit time - hacked client?");
				return;
			}

			// Place a block:
			ItemHandler->OnPlayerPlace(*m_Player, HeldItem, {a_BlockX, a_BlockY, a_BlockZ}, a_BlockFace, {a_CursorX, a_CursorY, a_CursorZ});
			return;
		}
		else if (!PlgMgr->CallHookPlayerUsingItem(*m_Player, a_BlockX, a_BlockY, a_BlockZ, a_BlockFace, a_CursorX, a_CursorY, a_CursorZ))
		{
			// All plugins agree with using the item.
			// Use an item in hand with a target block.

			cBlockInServerPluginInterface PluginInterface(*World);
			ItemHandler->OnItemUse(World, m_Player, PluginInterface, HeldItem, {a_BlockX, a_BlockY, a_BlockZ}, a_BlockFace);
			PlgMgr->CallHookPlayerUsedItem(*m_Player, a_BlockX, a_BlockY, a_BlockZ, a_BlockFace, a_CursorX, a_CursorY, a_CursorZ);
			return;
		}
	}

	// TODO: delete OnItemUse bool return, delete onCancelRightClick

	// Update the target block including the block above and below for 2 block high things:
	m_Player->SendBlocksAround(a_BlockX, a_BlockY, a_BlockZ, 2);

	// TODO: Send corresponding slot based on hand
	m_Player->GetInventory().SendEquippedSlot();
}





void cClientHandle::HandleChat(const AString & a_Message)
{
	if ((a_Message.size()) > MAX_CHAT_MSG_LENGTH)
	{
		Kick("Please don't exceed the maximum message length of " + std::to_string(MAX_CHAT_MSG_LENGTH));
		return;
	}
	// We no longer need to postpone message processing, because the messages already arrive in the Tick thread

	// If a command, perform it:
	AString Message(a_Message);
	if (cRoot::Get()->GetServer()->Command(*this, Message))
	{
		return;
	}

	// Not a command, broadcast as a message:
	cCompositeChat Msg;
	AString Color = m_Player->GetColor();
	if (Color.length() == 3)
	{
		Color = AString("@") + Color[2];
	}
	else
	{
		Color.clear();
	}
	Msg.AddTextPart("<");
	Msg.ParseText(m_Player->GetPrefix());
	Msg.AddTextPart(m_Player->GetName(), Color);
	Msg.ParseText(m_Player->GetSuffix());
	Msg.AddTextPart("> ");
	Msg.ParseText(Message);
	Msg.UnderlineUrls();
	cRoot::Get()->BroadcastChat(Msg);
}





void cClientHandle::HandlePlayerLook(float a_Rotation, float a_Pitch, bool a_IsOnGround)
{
	m_Player->SetYaw        (a_Rotation);
	m_Player->SetHeadYaw    (a_Rotation);
	m_Player->SetPitch      (a_Pitch);
	m_Player->SetTouchGround(a_IsOnGround);
}





void cClientHandle::HandlePlayerMove(double a_PosX, double a_PosY, double a_PosZ, bool a_IsOnGround)
{
	const Vector3d NewPosition(a_PosX, a_PosY, a_PosZ);
	const Vector3d OldPosition = GetPlayer()->GetPosition();
	const auto PreviousIsOnGround = GetPlayer()->IsOnGround();

#ifdef __clang__
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wfloat-equal"
#endif

	if (
		(OldPosition == NewPosition) &&
		(PreviousIsOnGround == a_IsOnGround)
	)
	{
		// Nothing changed, no need to do anything:
		return;
	}

#ifdef __clang__
#pragma clang diagnostic pop
#endif

	if (m_Player->IsFrozen() || (m_Player->GetHealth() <= 0))
	{
		// "Repair" if the client tries to move while frozen or dead:
		SendPlayerMoveLook();
		return;
	}

	// If the player has moved too far, "repair" them:
	if ((OldPosition - NewPosition).SqrLength() > 100 * 100)
	{
		LOGD("Too far away (%0.2f), \"repairing\" the client", (OldPosition - NewPosition).Length());
		SendPlayerMoveLook();
		return;
	}

	if (cRoot::Get()->GetPluginManager()->CallHookPlayerMoving(*m_Player, OldPosition, NewPosition, PreviousIsOnGround))
	{
		SendPlayerMoveLook();
		return;
	}

	// TODO: should do some checks to see if player is not moving through terrain
	// TODO: Official server refuses position packets too far away from each other, kicking "hacked" clients; we should, too

	m_Player->SetPosition(NewPosition);
	m_Player->SetTouchGround(a_IsOnGround);
	m_Player->UpdateMovementStats(NewPosition - OldPosition, PreviousIsOnGround);
}





void cClientHandle::HandlePlayerMoveLook(double a_PosX, double a_PosY, double a_PosZ, float a_Rotation, float a_Pitch, bool a_IsOnGround)
{
	HandlePlayerMove(a_PosX, a_PosY, a_PosZ, a_IsOnGround);
	HandlePlayerLook(a_Rotation, a_Pitch, a_IsOnGround);
}





void cClientHandle::HandleSlotSelected(Int16 a_SlotNum)
{
	m_Player->GetInventory().SetEquippedSlotNum(a_SlotNum);
	m_Player->GetWorld()->BroadcastEntityEquipment(*m_Player, 0, m_Player->GetInventory().GetEquippedItem(), this);
}





void cClientHandle::HandleSpectate(const cUUID & a_PlayerUUID)
{
	if (!m_Player->IsGameModeSpectator())
	{
		Kick("Tried to use spectator mode when not in game mode spectator.");
		return;
	}

	m_Player->GetWorld()->DoWithPlayerByUUID(a_PlayerUUID, [=](cPlayer & a_ToSpectate)
	{
		m_Player->TeleportToEntity(a_ToSpectate);
		return true;
	});
}





void cClientHandle::HandleSprint(const bool a_IsSprinting)
{
	m_Player->SetSprint(a_IsSprinting);
}





void cClientHandle::HandleStartElytraFlight()
{
	m_Player->SetElytraFlight(true);
}





void cClientHandle::HandleSteerVehicle(float a_Forward, float a_Sideways)
{
	m_Player->SteerVehicle(a_Forward, a_Sideways);
}





void cClientHandle::HandleWindowClose(UInt8 a_WindowID)
{
	m_Player->CloseWindowIfID(static_cast<char>(a_WindowID));
}





void cClientHandle::HandleWindowClick(UInt8 a_WindowID, Int16 a_SlotNum, eClickAction a_ClickAction, const cItem & a_HeldItem)
{
	LOGD("WindowClick: WinID %d, SlotNum %d, action: %s, Item %s x %d",
		a_WindowID, a_SlotNum, ClickActionToString(a_ClickAction),
		ItemToString(a_HeldItem).c_str(), a_HeldItem.m_ItemCount
	);

	cWindow * Window = m_Player->GetWindow();
	if (Window == nullptr)
	{
		LOGWARNING("Player \"%s\" clicked in a non-existent window. Ignoring", m_Username.c_str());
		return;
	}
	m_Player->AddKnownItem(a_HeldItem);
	Window->Clicked(*m_Player, a_WindowID, a_SlotNum, a_ClickAction, a_HeldItem);
}





void cClientHandle::HandleUpdateSign(
	int a_BlockX, int a_BlockY, int a_BlockZ,
	const AString & a_Line1, const AString & a_Line2,
	const AString & a_Line3, const AString & a_Line4
)
{
	if (m_LastPlacedSign.Equals(Vector3i(a_BlockX, a_BlockY, a_BlockZ)))
	{
		m_LastPlacedSign.Set(0, -1, 0);
		m_Player->GetWorld()->SetSignLines(a_BlockX, a_BlockY, a_BlockZ, a_Line1, a_Line2, a_Line3, a_Line4, m_Player);
	}
}





void cClientHandle::HandleUseEntity(UInt32 a_TargetEntityID, bool a_IsLeftClick)
{
	// TODO: Let plugins interfere via a hook

	// If the player is a spectator, let him spectate
	if (m_Player->IsGameModeSpectator() && a_IsLeftClick)
	{
		m_Player->GetWorld()->DoWithEntityByID(a_TargetEntityID, [=](cEntity & a_Entity)
		{
			m_Player->AttachTo(&a_Entity);
			return true;
		});
		return;
	}

	// If it is a right click, call the entity's OnRightClicked() handler:
	if (!a_IsLeftClick)
	{
		cWorld * World = m_Player->GetWorld();
		World->DoWithEntityByID(a_TargetEntityID, [=](cEntity & a_Entity)
			{
				if (
					cPluginManager::Get()->CallHookPlayerRightClickingEntity(*m_Player, a_Entity) ||
					(
						m_Player->IsGameModeSpectator() &&  // Spectators cannot interact with every entity
						(
							!a_Entity.IsMinecart() ||  // They can only interact with minecarts
							(
								(static_cast<cMinecart &>(a_Entity).GetPayload() != cMinecart::mpChest) &&  // And only if the type matches a minecart with a chest or
								(static_cast<cMinecart &>(a_Entity).GetPayload() != cMinecart::mpHopper)    // a minecart with a hopper
							)
						)
					)
				)
				{
					return false;
				}
				a_Entity.OnRightClicked(*m_Player);
				return false;
			}
		);
		return;
	}

	// If it is a left click, attack the entity:
	m_Player->GetWorld()->DoWithEntityByID(a_TargetEntityID, [=](cEntity & a_Entity)
		{
			if (!a_Entity.GetWorld()->IsPVPEnabled())
			{
				// PVP is disabled, disallow players hurting other players:
				if (a_Entity.IsPlayer())
				{
					// Player is hurting another player which is not allowed when PVP is disabled so ignore it
					return true;
				}
			}
			a_Entity.TakeDamage(*m_Player);
			m_Player->AddFoodExhaustion(0.3);
			if (a_Entity.IsPawn())
			{
				m_Player->NotifyNearbyWolves(static_cast<cPawn*>(&a_Entity), true);
			}
			return true;
		}
	);
}





void cClientHandle::HandleUseItem(bool a_UsedMainHand)
{
	// Use the held item without targeting a block: eating, drinking, charging a bow, using buckets
	// In version 1.8.x, this function shares the same packet id with HandleRightClick.
	// In version >= 1.9, there is a new packet id for "Use Item".

	// TODO: We are still consuming the items in main hand. Remove this override when the off-hand consumption is handled correctly.
	a_UsedMainHand = true;
	const cItem & HeldItem = a_UsedMainHand ? m_Player->GetEquippedItem() : m_Player->GetInventory().GetShieldSlot();
	cItemHandler * ItemHandler = cItemHandler::GetItemHandler(HeldItem.m_ItemType);
	cWorld * World = m_Player->GetWorld();
	cPluginManager * PlgMgr = cRoot::Get()->GetPluginManager();

	LOGD("HandleUseItem: Hand: %d; HeldItem: %s", a_UsedMainHand, ItemToFullString(HeldItem).c_str());

	if (PlgMgr->CallHookPlayerRightClick(*m_Player, -1, 255, -1, BLOCK_FACE_NONE, 0, 0, 0))
	{
		return;  // Plugin denied click action
	}

	// Use item in main / off hand
	// TODO: do we need to sync the current inventory with client if it fails?
	if (m_Player->IsFrozen() || m_Player->IsGameModeSpectator())
	{
		return;
	}

	if (ItemHandler->IsFood() || ItemHandler->IsDrinkable(HeldItem.m_ItemDamage))
	{
		if (
			ItemHandler->IsFood() &&
			(m_Player->IsSatiated() || m_Player->IsGameModeCreative()) &&  // Only non-creative or hungry players can eat
			(HeldItem.m_ItemType != E_ITEM_GOLDEN_APPLE) &&  // Golden apple is a special case, it is used instead of eaten
			(HeldItem.m_ItemType != E_ITEM_CHORUS_FRUIT)     // Chorus fruit is a special case, it is used instead of eaten
		)
		{
			// The player is satiated or in creative, and trying to eat
			return;
		}
		if (!PlgMgr->CallHookPlayerEating(*m_Player))
		{
			m_Player->StartEating();
		}
	}
	else
	{
		// Use an item in hand without a target block
		if (!PlgMgr->CallHookPlayerUsingItem(*m_Player, -1, 255, -1, BLOCK_FACE_NONE, 0, 0, 0))
		{
			// All plugins agree with using the item
			cBlockInServerPluginInterface PluginInterface(*World);
			ItemHandler->OnItemUse(World, m_Player, PluginInterface, HeldItem, {-1, 255, -1}, BLOCK_FACE_NONE);
			PlgMgr->CallHookPlayerUsedItem(*m_Player, -1, 255, -1, BLOCK_FACE_NONE, 0, 0, 0);
		}
	}
}





void cClientHandle::HandleRespawn(void)
{
	if (m_Player->GetHealth() > 0)
	{
		Kick("What is not dead may not live again. Hacked client?");
		return;
	}

	m_Player->Respawn();
	cRoot::Get()->GetPluginManager()->CallHookPlayerSpawned(*m_Player);
}





void cClientHandle::HandleKeepAlive(UInt32 a_KeepAliveID)
{
	if (a_KeepAliveID == m_PingID)
	{
		m_Ping = std::chrono::steady_clock::now() - m_PingStartTime;
	}
}





bool cClientHandle::CheckMultiLogin(const AString & a_Username)
{
	// If the multilogin is allowed, skip this check entirely:
	if ((cRoot::Get()->GetServer()->DoesAllowMultiLogin()))
	{
		return true;
	}

	// Check if the player is waiting to be transferred to the World.
	if (cRoot::Get()->GetServer()->IsPlayerInQueue(a_Username))
	{
		Kick("A player of the username is already logged in");
		return false;
	}

	// Check if the player is in any World.
	if (cRoot::Get()->DoWithPlayer(a_Username, [](cPlayer &) { return true; }))
	{
		Kick("A player of the username is already logged in");
		return false;
	}
	return true;
}





bool cClientHandle::HandleHandshake(const AString & a_Username)
{
	if (a_Username.length() > 16)
	{
		Kick("Your username is too long (>16 characters)");
		return false;
	}

	if (cRoot::Get()->GetPluginManager()->CallHookHandshake(*this, a_Username))
	{
		Kick("Entry denied by plugin");
		return false;
	}

	return CheckMultiLogin(a_Username);
}





void cClientHandle::HandleLeaveBed()
{
	cChunkInterface Interface(m_Player->GetWorld()->GetChunkMap());
	cBlockBedHandler::VacateBed(Interface, *m_Player);
}





void cClientHandle::HandleUnmount(void)
{
	m_Player->Detach();
}





void cClientHandle::HandleTabCompletion(const AString & a_Text)
{
	AStringVector Results;
	// Get player name completions.
	if (cRoot::Get()->GetServer()->ShouldAllowMultiWorldTabCompletion())
	{
		Results = cRoot::Get()->GetPlayerTabCompletionMultiWorld(a_Text);
	}
	else
	{
		m_Player->GetWorld()->TabCompleteUserName(a_Text, Results);
	}

	// Get command completions.
	cRoot::Get()->GetPluginManager()->TabCompleteCommand(a_Text, Results, m_Player);
	if (Results.empty())
	{
		return;
	}

	// Sort and send results.
	std::sort(Results.begin(), Results.end());
	SendTabCompletionResults(Results);
}





void cClientHandle::SendData(const ContiguousByteBufferView a_Data)
{
	if (m_HasSentDC)
	{
		// This could crash the client, because they've already unloaded the world etc., and suddenly a wild packet appears (#31)
		return;
	}

	cCSLock Lock(m_CSOutgoingData);
	m_OutgoingData += a_Data;
}





void cClientHandle::RemoveFromWorld(void)
{
	// Remove all associated chunks:
	{
		cCSLock Lock(m_CSChunkLists);
		m_LoadedChunks.clear();
		m_ChunksToSend.clear();
		m_SentChunks.clear();
	}

	// Flush outgoing data:
	ProcessProtocolOut();

	// No need to send Unload Chunk packets, the client unloads automatically.

	// Here, we set last streamed values to bogus ones so everything is resent:
	m_LastStreamedChunkX = std::numeric_limits<decltype(m_LastStreamedChunkX)>::max();
	m_LastStreamedChunkZ = std::numeric_limits<decltype(m_LastStreamedChunkZ)>::max();

	// Restart player unloaded chunk checking and freezing:
	m_CachedSentChunk = cChunkCoords(std::numeric_limits<decltype(m_CachedSentChunk.m_ChunkX)>::max(), std::numeric_limits<decltype(m_CachedSentChunk.m_ChunkZ)>::max());
}





bool cClientHandle::IsPlayerChunkSent()
{
	return m_HasSentPlayerChunk;
}





bool cClientHandle::CheckBlockInteractionsRate(void)
{
	ASSERT(m_Player != nullptr);
	ASSERT(m_Player->GetWorld() != nullptr);

	if (!cRoot::Get()->GetServer()->ShouldLimitPlayerBlockChanges())
	{
		return true;
	}

	return (m_NumBlockChangeInteractionsThisTick <= MAX_BLOCK_CHANGE_INTERACTIONS);
}





void cClientHandle::Tick(float a_Dt)
{
	using namespace std::chrono_literals;

	// anticheat fastbreak
	if (m_HasStartedDigging)
	{
		BLOCKTYPE Block = m_Player->GetWorld()->GetBlock({ m_LastDigBlockX, m_LastDigBlockY, m_LastDigBlockZ });
		m_BreakProgress += m_Player->GetMiningProgressPerTick(Block);
	}

	ProcessProtocolIn();

	if (IsDestroyed())
	{
		return;
	}

	m_TicksSinceLastPacket += 1;
	if (m_TicksSinceLastPacket > 600)  // 30 seconds time-out
	{
		SendDisconnect("Nooooo!! You timed out! D: Come back!");
		return;
	}

	// Freeze the player if they are standing in a chunk not yet sent to the client
	m_HasSentPlayerChunk = false;
	if (m_Player->GetParentChunk() != nullptr)
	{
		// If the chunk is invalid, it has definitely not been sent to the client yet
		if (m_Player->GetParentChunk()->IsValid())
		{
			// Before iterating m_SentChunks, see if the player's coords equal m_CachedSentChunk
			// If so, the chunk has been sent to the client. This is an optimization that saves an iteration of m_SentChunks.
			if (cChunkCoords(m_Player->GetChunkX(), m_Player->GetChunkZ()) == m_CachedSentChunk)
			{
				m_HasSentPlayerChunk = true;
			}
			else
			{
				// This block is entered only when the player moves to a new chunk, invalidating the cached coords.
				// Otherwise the cached coords are used.
				cCSLock Lock(m_CSChunkLists);
				auto itr = std::find(m_SentChunks.begin(), m_SentChunks.end(), cChunkCoords(m_Player->GetChunkX(), m_Player->GetChunkZ()));
				if (itr != m_SentChunks.end())
				{
					m_CachedSentChunk = *itr;
					m_HasSentPlayerChunk = true;
				}
			}
		}
	}

	// If the chunk the player's in was just sent, spawn the player:
	{
		cCSLock lock(m_CSState);
		if (m_HasSentPlayerChunk && (m_State == csDownloadingWorld))
		{
			m_Protocol->SendPlayerMoveLook();
			m_State = csPlaying;

			// Send resource pack (after a MoveLook, because sending it before the initial MoveLook cancels the download screen):
			if (const auto & ResourcePackUrl = cRoot::Get()->GetServer()->GetResourcePackUrl(); !ResourcePackUrl.empty())
			{
				SendResourcePack(ResourcePackUrl);
			}
		}
	}  // lock(m_CSState)

	// Send a ping packet:
	if (m_State == csPlaying)
	{
		const auto Now = std::chrono::steady_clock::now();
		if ((m_PingStartTime + std::chrono::seconds(2)) <= Now)  // 2 second interval between pings
		{
			m_PingID++;
			m_PingStartTime = Now;
			m_Protocol->SendKeepAlive(m_PingID);
		}
	}

	// Send a couple of chunks to the player:
	StreamNextChunks();

	// Unload all chunks that are out of the view distance (every 5 seconds):
	if ((m_Player->GetWorld()->GetWorldAge() - m_LastUnloadCheck) > 5s)
	{
		UnloadOutOfRangeChunks();
	}

	// Handle block break animation:
	if (m_BlockDigAnimStage > -1)
	{
		int lastAnimVal = m_BlockDigAnimStage;
		m_BlockDigAnimStage += static_cast<int>(m_BlockDigAnimSpeed * a_Dt);
		if (m_BlockDigAnimStage > 9000)
		{
			m_BlockDigAnimStage = 9000;
		}
		if (m_BlockDigAnimStage / 1000 != lastAnimVal / 1000)
		{
			m_Player->GetWorld()->BroadcastBlockBreakAnimation(static_cast<UInt32>(m_UniqueID), {m_BlockDigAnimX, m_BlockDigAnimY, m_BlockDigAnimZ}, static_cast<char>(m_BlockDigAnimStage / 1000), this);
		}
	}

	// Reset explosion & block change counters:
	m_NumExplosionsThisTick = 0;
	m_NumBlockChangeInteractionsThisTick = 0;
}





void cClientHandle::ServerTick(float a_Dt)
{
	ProcessProtocolIn();
	ProcessProtocolOut();

	m_TicksSinceLastPacket += 1;
	if (m_TicksSinceLastPacket > 600)  // 30 seconds
	{
		SendDisconnect("Nooooo!! You timed out! D: Come back!");
	}
}





void cClientHandle::SendAttachEntity(const cEntity & a_Entity, const cEntity & a_Vehicle)
{
	m_Protocol->SendAttachEntity(a_Entity, a_Vehicle);
}





void cClientHandle::SendLeashEntity(const cEntity & a_Entity, const cEntity & a_EntityLeashedTo)
{
	m_Protocol->SendLeashEntity(a_Entity, a_EntityLeashedTo);
}





void cClientHandle::SendUnleashEntity(const cEntity & a_Entity)
{
	m_Protocol->SendUnleashEntity(a_Entity);
}





void cClientHandle::SendBlockAction(int a_BlockX, int a_BlockY, int a_BlockZ, char a_Byte1, char a_Byte2, BLOCKTYPE a_BlockType)
{
	m_Protocol->SendBlockAction(a_BlockX, a_BlockY, a_BlockZ, a_Byte1, a_Byte2, a_BlockType);
}





void cClientHandle::SendBlockBreakAnim(UInt32 a_EntityID, int a_BlockX, int a_BlockY, int a_BlockZ, char a_Stage)
{
	m_Protocol->SendBlockBreakAnim(a_EntityID, a_BlockX, a_BlockY, a_BlockZ, a_Stage);
}





void cClientHandle::SendBlockChange(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta)
{
	int ChunkX, ChunkZ = 0;
	cChunkDef::BlockToChunk(a_BlockX, a_BlockZ, ChunkX, ChunkZ);
	cChunkCoords ChunkCoords = cChunkCoords(ChunkX, ChunkZ);

	// Do not send block changes in chunks that weren't sent to the client yet:
	cCSLock Lock(m_CSChunkLists);
	if (std::find(m_SentChunks.begin(), m_SentChunks.end(), ChunkCoords) != m_SentChunks.end())
	{
		Lock.Unlock();
		m_Protocol->SendBlockChange(a_BlockX, a_BlockY, a_BlockZ, a_BlockType, a_BlockMeta);
	}
}





void cClientHandle::SendBlockChanges(int a_ChunkX, int a_ChunkZ, const sSetBlockVector & a_Changes)
{
	ASSERT(!a_Changes.empty());  // We don't want to be sending empty change packets!

	// Do not send block changes in chunks that weren't sent to the client yet:
	{
		cCSLock Lock(m_CSChunkLists);
		if (std::find(m_SentChunks.begin(), m_SentChunks.end(), cChunkCoords(a_ChunkX, a_ChunkZ)) == m_SentChunks.end())
		{
			return;
		}
	}

	// Use a dedicated packet for single changes:
	if (a_Changes.size() == 1)
	{
		const auto & Change = a_Changes[0];
		m_Protocol->SendBlockChange(Change.GetX(), Change.GetY(), Change.GetZ(), Change.m_BlockType, Change.m_BlockMeta);
		return;
	}

	m_Protocol->SendBlockChanges(a_ChunkX, a_ChunkZ, a_Changes);
}





void cClientHandle::SendBossBarAdd(UInt32 a_UniqueID, const cCompositeChat & a_Title, float a_FractionFilled, BossBarColor a_Color, BossBarDivisionType a_DivisionType, bool a_DarkenSky, bool a_PlayEndMusic, bool a_CreateFog)
{
	m_Protocol->SendBossBarAdd(a_UniqueID, a_Title, a_FractionFilled, a_Color, a_DivisionType, a_DarkenSky, a_PlayEndMusic, a_CreateFog);
}





void cClientHandle::SendBossBarUpdateFlags(UInt32 a_UniqueID, bool a_DarkenSky, bool a_PlayEndMusic, bool a_CreateFog)
{
	m_Protocol->SendBossBarUpdateFlags(a_UniqueID, a_DarkenSky, a_PlayEndMusic, a_CreateFog);
}





void cClientHandle::SendBossBarUpdateStyle(UInt32 a_UniqueID, BossBarColor a_Color, BossBarDivisionType a_DivisionType)
{
	m_Protocol->SendBossBarUpdateStyle(a_UniqueID, a_Color, a_DivisionType);
}





void cClientHandle::SendBossBarUpdateTitle(UInt32 a_UniqueID, const cCompositeChat & a_Title)
{
	m_Protocol->SendBossBarUpdateTitle(a_UniqueID, a_Title);
}





void cClientHandle::SendBossBarRemove(UInt32 a_UniqueID)
{
	m_Protocol->SendBossBarRemove(a_UniqueID);
}





void cClientHandle::SendBossBarUpdateHealth(UInt32 a_UniqueID, float a_FractionFilled)
{
	m_Protocol->SendBossBarUpdateHealth(a_UniqueID, a_FractionFilled);
}





void cClientHandle::SendCameraSetTo(const cEntity & a_Entity)
{
	m_Protocol->SendCameraSetTo(a_Entity);
}





void cClientHandle::SendChat(const AString & a_Message, eMessageType a_ChatPrefix, const AString & a_AdditionalData)
{
	cWorld * World = GetPlayer()->GetWorld();
	if (World == nullptr)
	{
		World = cRoot::Get()->GetWorld(GetPlayer()->GetLoadedWorldName());
		if (World == nullptr)
		{
			World = cRoot::Get()->GetDefaultWorld();
		}
	}

	bool ShouldUsePrefixes = World->ShouldUseChatPrefixes();
	AString Message = FormatMessageType(ShouldUsePrefixes, a_ChatPrefix, a_AdditionalData);
	m_Protocol->SendChat(Message.append(a_Message), ctChatBox, ShouldUsePrefixes);
}





void cClientHandle::SendChat(const cCompositeChat & a_Message)
{
	cWorld * World = GetPlayer()->GetWorld();
	if (World == nullptr)
	{
		World = cRoot::Get()->GetWorld(GetPlayer()->GetLoadedWorldName());
		if (World == nullptr)
		{
			World = cRoot::Get()->GetDefaultWorld();
		}
	}

	bool ShouldUsePrefixes = World->ShouldUseChatPrefixes();
	m_Protocol->SendChat(a_Message, ctChatBox, ShouldUsePrefixes);
}





void cClientHandle::SendChatRaw(const AString & a_MessageRaw, eChatType a_Type)
{
	m_Protocol->SendChatRaw(a_MessageRaw, a_Type);
}





void cClientHandle::SendChatAboveActionBar(const AString & a_Message, eMessageType a_ChatPrefix, const AString & a_AdditionalData)
{
	cWorld * World = GetPlayer()->GetWorld();
	if (World == nullptr)
	{
		World = cRoot::Get()->GetWorld(GetPlayer()->GetLoadedWorldName());
		if (World == nullptr)
		{
			World = cRoot::Get()->GetDefaultWorld();
		}
	}

	AString Message = FormatMessageType(World->ShouldUseChatPrefixes(), a_ChatPrefix, a_AdditionalData);
	m_Protocol->SendChat(Message.append(a_Message), ctAboveActionBar);
}





void cClientHandle::SendChatAboveActionBar(const cCompositeChat & a_Message)
{
	m_Protocol->SendChat(a_Message, ctAboveActionBar, GetPlayer()->GetWorld()->ShouldUseChatPrefixes());
}





void cClientHandle::SendChatSystem(const AString & a_Message, eMessageType a_ChatPrefix, const AString & a_AdditionalData)
{
	cWorld * World = GetPlayer()->GetWorld();
	if (World == nullptr)
	{
		World = cRoot::Get()->GetWorld(GetPlayer()->GetLoadedWorldName());
		if (World == nullptr)
		{
			World = cRoot::Get()->GetDefaultWorld();
		}
	}

	auto ShouldUsePrefixes = World->ShouldUseChatPrefixes();
	AString Message = FormatMessageType(ShouldUsePrefixes, a_ChatPrefix, a_AdditionalData);
	m_Protocol->SendChat(Message.append(a_Message), ctSystem, ShouldUsePrefixes);
}





void cClientHandle::SendChatSystem(const cCompositeChat & a_Message)
{
	m_Protocol->SendChat(a_Message, ctSystem, GetPlayer()->GetWorld()->ShouldUseChatPrefixes());
}





void cClientHandle::SendChunkData(int a_ChunkX, int a_ChunkZ, const ContiguousByteBufferView a_ChunkData)
{
	ASSERT(m_Player != nullptr);

	// Check chunks being sent, erase them from m_ChunksToSend:
	bool Found = false;
	{
		cCSLock Lock(m_CSChunkLists);
		auto itr = m_ChunksToSend.find(cChunkCoords{a_ChunkX, a_ChunkZ});
		if (itr != m_ChunksToSend.end())
		{
			m_ChunksToSend.erase(itr);
			Found = true;
		}
	}
	if (!Found)
	{
		// This just sometimes happens. If you have a reliably replicatable situation for this, go ahead and fix it
		// It's not a big issue anyway, just means that some chunks may be compressed several times
		// LOG("Refusing to send    chunk [%d, %d] to client \"%s\" at [%d, %d].", a_ChunkX, a_ChunkZ, m_Username.c_str(), m_Player->GetChunkX(), m_Player->GetChunkZ());
		// 2020 08 21: seems to happen going through nether portals on 1.8.9
		return;
	}

	if (!m_Protocol.VersionRecognitionSuccessful())
	{
		// TODO (#2588): investigate if and why this occurs
		return;
	}

	m_Protocol->SendChunkData(a_ChunkData);

	// Add the chunk to the list of chunks sent to the player:
	{
		cCSLock Lock(m_CSChunkLists);
		m_SentChunks.emplace_back(a_ChunkX, a_ChunkZ);
	}
}





void cClientHandle::SendCollectEntity(const cEntity & a_Collected, const cEntity & a_Collector, unsigned a_Count)
{
	m_Protocol->SendCollectEntity(a_Collected, a_Collector, a_Count);
}





void cClientHandle::SendDestroyEntity(const cEntity & a_Entity)
{
	m_Protocol->SendDestroyEntity(a_Entity);
}





void cClientHandle::SendDetachEntity(const cEntity & a_Entity, const cEntity & a_PreviousVehicle)
{
	m_Protocol->SendDetachEntity(a_Entity, a_PreviousVehicle);
}





void cClientHandle::SendDisconnect(const AString & a_Reason)
{
	LOGD("Sending a DC: \"%s\"", StripColorCodes(a_Reason).c_str());

	m_Protocol.SendDisconnect(*this, a_Reason);
	m_HasSentDC = true;
	Destroy();
}





void cClientHandle::SendEditSign(int a_BlockX, int a_BlockY, int a_BlockZ)
{
	m_LastPlacedSign.Set(a_BlockX, a_BlockY, a_BlockZ);
	m_Protocol->SendEditSign(a_BlockX, a_BlockY, a_BlockZ);
}





void cClientHandle::SendEntityEffect(const cEntity & a_Entity, int a_EffectID, int a_Amplifier, int a_Duration)
{
	m_Protocol->SendEntityEffect(a_Entity, a_EffectID, a_Amplifier, a_Duration);
}





void cClientHandle::SendEntityEquipment(const cEntity & a_Entity, short a_SlotNum, const cItem & a_Item)
{
	m_Protocol->SendEntityEquipment(a_Entity, a_SlotNum, a_Item);
}





void cClientHandle::SendEntityHeadLook(const cEntity & a_Entity)
{
	ASSERT(a_Entity.GetUniqueID() != m_Player->GetUniqueID());  // Must not send for self

	m_Protocol->SendEntityHeadLook(a_Entity);
}





void cClientHandle::SendEntityLook(const cEntity & a_Entity)
{
	ASSERT(a_Entity.GetUniqueID() != m_Player->GetUniqueID());  // Must not send for self

	m_Protocol->SendEntityLook(a_Entity);
}





void cClientHandle::SendEntityMetadata(const cEntity & a_Entity)
{
	m_Protocol->SendEntityMetadata(a_Entity);
}





void cClientHandle::SendEntityPosition(const cEntity & a_Entity)
{
	m_Protocol->SendEntityPosition(a_Entity);
}





void cClientHandle::SendEntityProperties(const cEntity & a_Entity)
{
	m_Protocol->SendEntityProperties(a_Entity);
}





void cClientHandle::SendEntityVelocity(const cEntity & a_Entity)
{
	m_Protocol->SendEntityVelocity(a_Entity);
}





void cClientHandle::SendExplosion(const Vector3f a_Position, const float a_Power)
{
	if (m_NumExplosionsThisTick > MAX_EXPLOSIONS_PER_TICK)
	{
		LOGD("Dropped an explosion!");
		return;
	}

	// Update the statistics:
	m_NumExplosionsThisTick++;

	auto & Random = GetRandomProvider();
	const auto SoundPitchMultiplier = 1.0f + (Random.RandReal() - Random.RandReal()) * 0.2f;

	// Sound:
	SendSoundEffect("entity.generic.explode", a_Position, 4.0f, SoundPitchMultiplier * 0.7f);

	const auto ParticleFormula = a_Power * 0.33f;
	auto Spread = ParticleFormula * 0.5f;
	auto ParticleCount = std::min(static_cast<int>(ParticleFormula * 125), 600);

	// Dark smoke particles:
	SendParticleEffect("largesmoke", a_Position.x, a_Position.y, a_Position.z, 0, 0, 0, Spread, static_cast<int>(ParticleCount));

	Spread = ParticleFormula * 0.35f;
	ParticleCount = std::min(static_cast<int>(ParticleFormula * 550), 1800);

	// Light smoke particles:
	SendParticleEffect("explode", a_Position.x, a_Position.y, a_Position.z, 0, 0, 0, Spread, static_cast<int>(ParticleCount));

	// Shockwave effect:
	m_Protocol->SendExplosion(a_Position, a_Power);
}





void cClientHandle::SendGameMode(eGameMode a_GameMode)
{
	m_Protocol->SendGameMode(a_GameMode);
}





void cClientHandle::SendHealth(void)
{
	m_Protocol->SendHealth();
}





void cClientHandle::SendHeldItemChange(int a_ItemIndex)
{
	m_Protocol->SendHeldItemChange(a_ItemIndex);
}





void cClientHandle::SendHideTitle(void)
{
	m_Protocol->SendHideTitle();
}





void cClientHandle::SendInventorySlot(char a_WindowID, short a_SlotNum, const cItem & a_Item)
{
	m_Protocol->SendInventorySlot(a_WindowID, a_SlotNum, a_Item);
}





void cClientHandle::SendMapData(const cMap & a_Map, int a_DataStartX, int a_DataStartY)
{
	m_Protocol->SendMapData(a_Map, a_DataStartX, a_DataStartY);
}





void cClientHandle::SendParticleEffect(const AString & a_ParticleName, float a_SrcX, float a_SrcY, float a_SrcZ, float a_OffsetX, float a_OffsetY, float a_OffsetZ, float a_ParticleData, int a_ParticleAmount)
{
	m_Protocol->SendParticleEffect(a_ParticleName, a_SrcX, a_SrcY, a_SrcZ, a_OffsetX, a_OffsetY, a_OffsetZ, a_ParticleData, a_ParticleAmount);
}





void cClientHandle::SendParticleEffect(const AString & a_ParticleName, const Vector3f a_Src, const Vector3f a_Offset, float a_ParticleData, int a_ParticleAmount, std::array<int, 2> a_Data)
{
	m_Protocol->SendParticleEffect(a_ParticleName, a_Src, a_Offset, a_ParticleData, a_ParticleAmount, a_Data);
}





void cClientHandle::SendPaintingSpawn(const cPainting & a_Painting)
{
	m_Protocol->SendPaintingSpawn(a_Painting);
}





void cClientHandle::SendEntityAnimation(const cEntity & a_Entity, EntityAnimation a_Animation)
{
	m_Protocol->SendEntityAnimation(a_Entity, a_Animation);
}





void cClientHandle::SendPlayerAbilities()
{
	m_Protocol->SendPlayerAbilities();
}





void cClientHandle::SendPlayerListAddPlayer(const cPlayer & a_Player)
{
	m_Protocol->SendPlayerListAddPlayer(a_Player);
}





void cClientHandle::SendPlayerListHeaderFooter(const cCompositeChat & a_Header, const cCompositeChat & a_Footer)
{
	m_Protocol->SendPlayerListHeaderFooter(a_Header, a_Footer);
}





void cClientHandle::SendPlayerListRemovePlayer(const cPlayer & a_Player)
{
	m_Protocol->SendPlayerListRemovePlayer(a_Player);
}





void cClientHandle::SendPlayerListUpdateDisplayName(const cPlayer & a_Player, const AString & a_CustomName)
{
	m_Protocol->SendPlayerListUpdateDisplayName(a_Player, a_CustomName);
}





void cClientHandle::SendPlayerListUpdateGameMode(const cPlayer & a_Player)
{
	m_Protocol->SendPlayerListUpdateGameMode(a_Player);
}





void cClientHandle::SendPlayerListUpdatePing()
{
	m_Protocol->SendPlayerListUpdatePing();
}





void cClientHandle::SendPlayerMoveLook(void)
{
	/*
	FLOGD("Sending PlayerMoveLook: {0:0.2f}, stance {1:0.2f}, OnGround: {2}",
		m_Player->GetPosition(), m_Player->GetStance(), m_Player->IsOnGround()
	);
	*/
	m_Protocol->SendPlayerMoveLook();
}





void cClientHandle::SendPlayerPosition(void)
{
	m_Protocol->SendPlayerPosition();
}





void cClientHandle::SendPlayerSpawn(const cPlayer & a_Player)
{
	if (a_Player.GetUniqueID() == m_Player->GetUniqueID())
	{
		// Do NOT send this packet to myself
		return;
	}

	LOGD("Spawning player \"%s\" on client \"%s\" @ %s",
		a_Player.GetName().c_str(), GetPlayer()->GetName().c_str(), GetIPString().c_str()
	);

	m_Protocol->SendPlayerSpawn(a_Player);
}





void cClientHandle::SendPluginMessage(const AString & a_Channel, const std::string_view a_Message)
{
	m_Protocol->SendPluginMessage(a_Channel, { reinterpret_cast<const std::byte *>(a_Message.data()), a_Message.size() });
}





void cClientHandle::SendPluginMessage(const AString & a_Channel, const ContiguousByteBufferView a_Message)
{
	m_Protocol->SendPluginMessage(a_Channel, a_Message);
}





void cClientHandle::SendRemoveEntityEffect(const cEntity & a_Entity, int a_EffectID)
{
	m_Protocol->SendRemoveEntityEffect(a_Entity, a_EffectID);
}





void cClientHandle::SendResetTitle()
{
	m_Protocol->SendResetTitle();
}





void cClientHandle::SendRespawn(eDimension a_Dimension, bool a_ShouldIgnoreDimensionChecks)
{
	if (!a_ShouldIgnoreDimensionChecks && (a_Dimension == m_Player->GetWorld()->GetDimension()))
	{
		// The client goes crazy if we send a respawn packet with the dimension of the current world
		// So we send a temporary one first.
		// This is not needed when the player dies, hence the a_ShouldIgnoreDimensionChecks flag.
		// a_ShouldIgnoreDimensionChecks is true only at cPlayer::Respawn, which is called after
		// the player dies.
		eDimension TemporaryDimension = (a_Dimension == dimOverworld) ? dimNether : dimOverworld;
		m_Protocol->SendRespawn(TemporaryDimension);
	}

	m_Protocol->SendRespawn(a_Dimension);
}





void cClientHandle::SendExperience(void)
{
	m_Protocol->SendExperience();
}





void cClientHandle::SendExperienceOrb(const cExpOrb & a_ExpOrb)
{
	m_Protocol->SendExperienceOrb(a_ExpOrb);
}





void cClientHandle::SendResourcePack(const AString & a_ResourcePackUrl)
{
	m_Protocol->SendResourcePack(a_ResourcePackUrl);
}





void cClientHandle::SendScoreboardObjective(const AString & a_Name, const AString & a_DisplayName, Byte a_Mode)
{
	m_Protocol->SendScoreboardObjective(a_Name, a_DisplayName, a_Mode);
}





void cClientHandle::SendScoreUpdate(const AString & a_Objective, const AString & a_Player, cObjective::Score a_Score, Byte a_Mode)
{
	m_Protocol->SendScoreUpdate(a_Objective, a_Player, a_Score, a_Mode);
}





void cClientHandle::SendDisplayObjective(const AString & a_Objective, cScoreboard::eDisplaySlot a_Display)
{
	m_Protocol->SendDisplayObjective(a_Objective, a_Display);
}





void cClientHandle::SendSetSubTitle(const cCompositeChat & a_SubTitle)
{
	m_Protocol->SendSetSubTitle(a_SubTitle);
}





void cClientHandle::SendSetRawSubTitle(const AString & a_SubTitle)
{
	m_Protocol->SendSetRawSubTitle(a_SubTitle);
}





void cClientHandle::SendSetTitle(const cCompositeChat & a_Title)
{
	m_Protocol->SendSetTitle(a_Title);
}





void cClientHandle::SendSetRawTitle(const AString & a_Title)
{
	m_Protocol->SendSetRawTitle(a_Title);
}





void cClientHandle::SendSoundEffect(const AString & a_SoundName, double a_X, double a_Y, double a_Z, float a_Volume, float a_Pitch)
{
	LOG("SendSoundEffect with double args is deprecated, use version with vector position parameter.");
	SendSoundEffect(a_SoundName, {a_X, a_Y, a_Z}, a_Volume, a_Pitch);
}





void cClientHandle::SendSoundEffect(const AString & a_SoundName, Vector3d a_Position, float a_Volume, float a_Pitch)
{
	m_Protocol->SendSoundEffect(a_SoundName, a_Position.x, a_Position.y, a_Position.z, a_Volume, a_Pitch);
}





void cClientHandle::SendSoundParticleEffect(const EffectID a_EffectID, int a_SrcX, int a_SrcY, int a_SrcZ, int a_Data)
{
	m_Protocol->SendSoundParticleEffect(a_EffectID, a_SrcX, a_SrcY, a_SrcZ, a_Data);
}





void cClientHandle::SendSpawnEntity(const cEntity & a_Entity)
{
	m_Protocol->SendSpawnEntity(a_Entity);
}





void cClientHandle::SendSpawnMob(const cMonster & a_Mob)
{
	m_Protocol->SendSpawnMob(a_Mob);
}





void cClientHandle::SendStatistics(const StatisticsManager & a_Manager)
{
	m_Protocol->SendStatistics(a_Manager);
}





void cClientHandle::SendTabCompletionResults(const AStringVector & a_Results)
{
	m_Protocol->SendTabCompletionResults(a_Results);
}





void cClientHandle::SendThunderbolt(int a_BlockX, int a_BlockY, int a_BlockZ)
{
	m_Protocol->SendThunderbolt(a_BlockX, a_BlockY, a_BlockZ);
}





void cClientHandle::SendTitleTimes(int a_FadeInTicks, int a_DisplayTicks, int a_FadeOutTicks)
{
	m_Protocol->SendTitleTimes(a_FadeInTicks, a_DisplayTicks, a_FadeOutTicks);
}





void cClientHandle::SendTimeUpdate(const cTickTimeLong a_WorldAge, const cTickTimeLong a_WorldDate, const bool a_DoDaylightCycle)
{
	m_Protocol->SendTimeUpdate(a_WorldAge, a_WorldDate, a_DoDaylightCycle);
}





void cClientHandle::SendUnloadChunk(int a_ChunkX, int a_ChunkZ)
{
	// Remove the chunk from the list of chunks sent to the client:
	{
		cCSLock Lock(m_CSChunkLists);
		m_SentChunks.remove(cChunkCoords(a_ChunkX, a_ChunkZ));
	}

	m_Protocol->SendUnloadChunk(a_ChunkX, a_ChunkZ);
}





void cClientHandle::SendUpdateBlockEntity(cBlockEntity & a_BlockEntity)
{
	m_Protocol->SendUpdateBlockEntity(a_BlockEntity);
}





void cClientHandle::SendUpdateSign(
	int a_BlockX, int a_BlockY, int a_BlockZ,
	const AString & a_Line1, const AString & a_Line2, const AString & a_Line3, const AString & a_Line4
)
{
	m_Protocol->SendUpdateSign(
		a_BlockX, a_BlockY, a_BlockZ,
		a_Line1, a_Line2, a_Line3, a_Line4
	);
}





void cClientHandle::SendUnlockRecipe(UInt32 a_RecipeId)
{
	m_Protocol->SendUnlockRecipe(a_RecipeId);
}





void cClientHandle::SendInitRecipes(UInt32 a_RecipeId)
{
	m_Protocol->SendInitRecipes(a_RecipeId);
}





void cClientHandle::HandleCraftRecipe(UInt32 a_RecipeId)
{
	auto * Window = m_Player->GetWindow();
	if (Window == nullptr)
	{
		return;
	}

	if (Window->GetWindowType() == cWindow::wtInventory)
	{
		static_cast<cInventoryWindow *>(Window)->LoadRecipe(*m_Player, a_RecipeId);
	}
	else if (Window->GetWindowType() == cWindow::wtWorkbench)
	{
		static_cast<cCraftingWindow *>(Window)->LoadRecipe(*m_Player, a_RecipeId);
	}
}





void cClientHandle::SendWeather(eWeather a_Weather)
{
	m_Protocol->SendWeather(a_Weather);
}





void cClientHandle::SendWholeInventory(const cWindow & a_Window)
{
	m_Protocol->SendWholeInventory(a_Window);
}





void cClientHandle::SendWindowClose(const cWindow & a_Window)
{
	m_Protocol->SendWindowClose(a_Window);
}





void cClientHandle::SendWindowOpen(const cWindow & a_Window)
{
	m_Protocol->SendWindowOpen(a_Window);
}





void cClientHandle::SendWindowProperty(const cWindow & a_Window, size_t a_Property, short a_Value)
{
	m_Protocol->SendWindowProperty(a_Window, a_Property, a_Value);
}





const AString & cClientHandle::GetUsername(void) const
{
	return m_Username;
}





void cClientHandle::SetUsername(AString && a_Username)
{
	m_Username = std::move(a_Username);
}





void cClientHandle::SetViewDistance(int a_ViewDistance)
{
	m_RequestedViewDistance = a_ViewDistance;
	LOGD("%s is requesting ViewDistance of %d!", GetUsername().c_str(), m_RequestedViewDistance);

	cWorld * world = m_Player->GetWorld();
	if (world != nullptr)
	{
		// Set the current view distance based on the requested VD and world max VD:
		m_CurrentViewDistance = Clamp(a_ViewDistance, cClientHandle::MIN_VIEW_DISTANCE, world->GetMaxViewDistance());

		// Restart chunk streaming to respond to new view distance:
		m_LastStreamedChunkX = std::numeric_limits<decltype(m_LastStreamedChunkX)>::max();
		m_LastStreamedChunkZ = std::numeric_limits<decltype(m_LastStreamedChunkZ)>::max();
	}
}





bool cClientHandle::HasPluginChannel(const AString & a_PluginChannel)
{
	return (m_PluginChannels.find(a_PluginChannel) != m_PluginChannels.end());
}





bool cClientHandle::WantsSendChunk(int a_ChunkX, int a_ChunkZ)
{
	if (m_State >= csDestroyed)
	{
		return false;
	}

	cCSLock Lock(m_CSChunkLists);
	return m_ChunksToSend.find(cChunkCoords(a_ChunkX, a_ChunkZ)) != m_ChunksToSend.end();
}





void cClientHandle::AddWantedChunk(int a_ChunkX, int a_ChunkZ)
{
	if (m_State >= csDestroyed)
	{
		return;
	}

	LOGD("Adding chunk [%d, %d] to wanted chunks for client %p", a_ChunkX, a_ChunkZ, static_cast<void *>(this));
	cCSLock Lock(m_CSChunkLists);
	if (m_ChunksToSend.find(cChunkCoords(a_ChunkX, a_ChunkZ)) == m_ChunksToSend.end())
	{
		m_ChunksToSend.emplace(a_ChunkX, a_ChunkZ);
	}
}





void cClientHandle::PacketBufferFull(void)
{
	// Too much data in the incoming queue, the server is probably too busy, kick the client:
	LOGERROR("Too much data in queue for client \"%s\" @ %s, kicking them.", m_Username.c_str(), m_IPString.c_str());
	SendDisconnect("The server is busy; please try again later.");
}





void cClientHandle::PacketUnknown(UInt32 a_PacketType)
{
	LOGERROR("Unknown packet type 0x%x from client \"%s\" @ %s", a_PacketType, m_Username.c_str(), m_IPString.c_str());

	AString Reason;
	Printf(Reason, "Unknown [C->S] PacketType: 0x%x", a_PacketType);
	SendDisconnect(Reason);
}





void cClientHandle::PacketError(UInt32 a_PacketType)
{
	LOGERROR("Protocol error while parsing packet type 0x%02x; disconnecting client \"%s\"", a_PacketType, m_Username.c_str());
	SendDisconnect("Protocol error");
}





void cClientHandle::SocketClosed(void)
{
	// The socket has been closed for any reason
	/*
	LOGD("SocketClosed for client %s @ %s (%p), state = %d, m_Player = %p",
		m_Username.c_str(), m_IPString.c_str(), static_cast<void *>(this), m_State.load(), static_cast<void *>(m_Player)
	);
	//*/

	// Log into console, unless it's a client ping:
	if (!m_Username.empty())
	{
		LOGD("Client %s @ %s disconnected", m_Username.c_str(), m_IPString.c_str());
		cRoot::Get()->GetPluginManager()->CallHookDisconnect(*this, "Player disconnected");
	}

	// Queue self for destruction:
	Destroy();
}





bool cClientHandle::SetState(eState a_NewState)
{
	cCSLock Lock(m_CSState);
	if (a_NewState <= m_State)
	{
		return false;  // Can only advance the state machine
	}
	m_State = a_NewState;
	return true;
}





void cClientHandle::ProcessProtocolIn(void)
{
	// Process received network data:
	decltype(m_IncomingData) IncomingData;
	{
		cCSLock Lock(m_CSIncomingData);

		// Bail out when nothing was received:
		if (m_IncomingData.empty())
		{
			return;
		}

		std::swap(IncomingData, m_IncomingData);
	}

	try
	{
		m_Protocol.HandleIncomingData(*this, IncomingData);
	}
	catch (const std::exception & Oops)
	{
		Kick(Oops.what());
	}
}





void cClientHandle::OnLinkCreated(cTCPLinkPtr a_Link)
{
	m_Link = a_Link;
}





void cClientHandle::OnReceivedData(const char * a_Data, size_t a_Length)
{
	// Reset the timeout:
	m_TicksSinceLastPacket = 0;

	// Queue the incoming data to be processed in the tick thread:
	cCSLock Lock(m_CSIncomingData);
	m_IncomingData.append(reinterpret_cast<const std::byte *>(a_Data), a_Length);
}





void cClientHandle::OnRemoteClosed(void)
{
	/*
	LOGD("Client socket for %s @ %s has been closed.",
		m_Username.c_str(), m_IPString.c_str()
	);
	//*/
	SocketClosed();
}





void cClientHandle::OnError(int a_ErrorCode, const AString & a_ErrorMsg)
{
	LOGD("An error has occurred on client link for %s @ %s: %d (%s). Client disconnected.",
		m_Username.c_str(), m_IPString.c_str(), a_ErrorCode, a_ErrorMsg.c_str()
	);
	SocketClosed();
}