// =================================================================================================

// eModbus: Copyright 2020 by Michael Harwerth, Bert Melis and the contributors to eModbus

// MIT license - see license.md for details

// =================================================================================================

#ifndef _MODBUS_SERVER_H

#define _MODBUS_SERVER_H

#include "options.h"

#include <map>

#include <vector>

#include <functional>

#if USE_MUTEX

#include <mutex> // NOLINT

#endif

#include "ModbusTypeDefs.h"

#include "ModbusError.h"

#include "ModbusMessage.h"

#if USE_MUTEX

using std::mutex;

using std::lock_guard;

#endif

// Standard response variants for "no response" and "echo the request"

const ModbusMessage NIL_RESPONSE (std::vector<uint8_t>{0xFF, 0xF0});

const ModbusMessage ECHO_RESPONSE(std::vector<uint8_t>{0xFF, 0xF1});

// MBSworker: function signature for worker functions to handle single serverID/functionCode combinations

using MBSworker = std::function<ModbusMessage(ModbusMessage msg)>;

using MBSExResponseWorker = std::function<ModbusMessage(ModbusMessage responseMsg, ModbusMessage requestMsg)>;

class ModbusServer {

public:

// registerWorker: register a worker function for a certain serverID/FC combination

// If there is one already, it will be overwritten!

void registerWorker(uint8_t serverID, uint8_t functionCode, MBSworker worker);

// getWorker: if a worker function is registered, return its address, nullptr otherwise

MBSworker getWorker(uint8_t serverID, uint8_t functionCode);

// unregisterWorker; remove again all or part of the registered workers for a given server ID

// Returns true if the worker was found and removed

bool unregisterWorker(uint8_t serverID, uint8_t functionCode = 0);

// isServerFor: if a worker function is registered for the given serverID, return true

bool isServerFor(uint8_t serverID, uint8_t functionCode);

// isServerFor: short version to look up if the server is known at all

bool isServerFor(uint8_t serverID);

// getMessageCount: read number of messages processed

uint32_t getMessageCount();

// getErrorCount: read number of errors responded

uint32_t getErrorCount();

// resetCounts: set both message and error counts to zero

void resetCounts();

// Local request to the server

ModbusMessage localRequest(ModbusMessage msg);

// listServer: print out all server/FC combinations served

void listServer();

protected:

// Constructor

ModbusServer();

// Destructor

virtual ~ModbusServer();

// Prevent copy construction or assignment

ModbusServer(ModbusServer& other) = delete;

ModbusServer& operator=(ModbusServer& other) = delete;

std::map<uint8_t, std::map<uint8_t, MBSworker>> workerMap; // map on serverID->functionCode->worker function

uint32_t messageCount; // Number of Requests processed

uint32_t errorCount; // Number of errors responded

#if USE_MUTEX

mutex m; // mutex to cover changes to messageCount and errorCount

#endif

};

#endif