FirmataTransport.h

#pragma once
/*
  FirmataTransport.h
  Copyright (c) 2025 Phil Schatzmann. All right reserved.
 
  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.
 
  This library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  Lesser General Public License for more details.
 
  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifdef USE_FIRMATA
#include "api/Stream.h"
#include <atomic>
#include <cstdint>
#include <functional>
#include <map>
#include <mutex>
#include <thread>
#include <vector>
 
namespace arduino {
 
struct FirmataDigitalMessage {
  uint8_t port;
  uint16_t value;
};
 
struct FirmataAnalogMessage {
  uint8_t pin;
  int value;
};
 
struct FirmataSysexMessage {
  uint8_t command;
  std::vector<uint8_t> data;
};
 
class FirmataTransport {
 public:
  using DigitalHandler = std::function<void(const FirmataDigitalMessage&)>;
  using AnalogHandler = std::function<void(const FirmataAnalogMessage&)>;
  using SysexHandler = std::function<void(const FirmataSysexMessage&)>;
 
  ~FirmataTransport();
 
  bool begin(Stream& stream);
 
  void end();
 
  operator bool() const { return running_.load(); }
 
  void writeBytes(const uint8_t* data, size_t len);
  void writeByte(uint8_t b) { writeBytes(&b, 1); }
 
  void onDigitalMessage(DigitalHandler handler) {
    digital_handler_ = std::move(handler);
  }
 
  void onAnalogMessage(AnalogHandler handler) {
    analog_handler_ = std::move(handler);
  }
 
  void addSysexHandler(uint8_t command, SysexHandler handler);
 
  void removeSysexHandler(uint8_t command);
 
 private:
  Stream* stream_ = nullptr;
  std::atomic<bool> running_{false};
  std::thread thread_;
  std::mutex write_mutex_;
 
  DigitalHandler digital_handler_;
  AnalogHandler analog_handler_;
  std::mutex sysex_handlers_mutex_;
  std::map<uint8_t, SysexHandler> sysex_handlers_;
 
  void readerLoop();
};
 
}  // namespace arduino
 
#endif  // USE_FIRMATA