#pragma once
#include "Protocol.h"
// Adjust these if a new protocol is added or an old one is removed:
#define MCS_CLIENT_VERSIONS "1.8.x-1.12.x"
#define MCS_PROTOCOL_VERSIONS "47, 107, 108, 109, 110, 210, 315, 316, 335, 338, 340"
#define MCS_LATEST_PROTOCOL_VERSION 340
/** Meta-protocol that recognizes multiple protocol versions, creates the specific
protocol version instance and redirects everything to it. */
class cMultiVersionProtocol
{
public:
cMultiVersionProtocol();
/** Translates protocol version number into protocol version text: 49 -> "1.4.4" */
static AString GetVersionTextFromInt(cProtocol::Version a_ProtocolVersion);
/** Returns if we contain a concrete protocol corresponding to the client's protocol version. */
bool VersionRecognitionSuccessful()
{
return m_Protocol != nullptr;
}
/** Convenience overload to enable redirecting sends to the underlying implementation. */
auto & operator->()
{
return m_Protocol;
}
/** The function that's responsible for processing incoming protocol data. */
std::function<void(cClientHandle &, std::string_view)> HandleIncomingData;
/** Sends a disconnect to the client as a result of a recognition error.
This function can be used to disconnect before any protocol has been recognised. */
void SendDisconnect(cClientHandle & a_Client, const AString & a_Reason);
private:
/** Handles data reception in a newly-created client handle that doesn't yet have known protocol.
a_Data contains a view of data that were just received.
Calls TryRecognizeProtocol to populate m_Protocol, and transitions to another mode depending on success. */
void HandleIncomingDataInRecognitionStage(cClientHandle & a_Client, std::string_view a_Data);
/** Handles and responds to unsupported clients sending pings. */
void HandleIncomingDataInOldPingResponseStage(cClientHandle & a_Client, const std::string_view a_Data);
/* Tries to recognize a protocol based on a_Data and m_Buffer contents.
a_Data is replaced with a sub-view, with handshake packet removed. */
void TryRecognizeProtocol(cClientHandle & a_Client, std::string_view & a_Data);
/** Tries to recognize a protocol in the lengthed family (1.7+), based on m_Buffer.
The packet length and type have already been read, type is 0.
Returns a cProtocol_XXX instance if recognized. */
std::unique_ptr<cProtocol> TryRecognizeLengthedProtocol(cClientHandle & a_Client, std::string_view & a_Data);
/** Sends one packet inside a cByteBuffer.
This is used only when handling an outdated server ping. */
static void SendPacket(cClientHandle & a_Client, cByteBuffer & a_OutPacketBuffer);
/** Returns the protocol-specific packet ID given the protocol-agnostic packet enum. */
static UInt32 GetPacketID(cProtocol::ePacketType a_PacketType);
/* Status handler for unrecognised versions. */
void HandlePacketStatusRequest(cClientHandle & a_Client, cByteBuffer & a_Out);
/* Ping handler for unrecognised versions. */
void HandlePacketStatusPing(cClientHandle & a_Client, cByteBuffer & a_Out);
/** The actual protocol implementation.
Created when recognition of the client version succeeds with a version we support. */
std::unique_ptr<cProtocol> m_Protocol;
/** Buffer for received protocol data. */
cByteBuffer m_Buffer;
} ;
