HardwareI2C_FIR.h

#pragma once
/*
  HardwareI2C_FIR.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/HardwareI2C.h"
#include "FirmataTransport.h"
#include <condition_variable>
#include <deque>
#include <memory>
#include <mutex>
#include <vector>
 
namespace arduino {
 
class HardwareI2C_FIRMATA : public HardwareI2C {
 public:
  HardwareI2C_FIRMATA() = default;
  ~HardwareI2C_FIRMATA();
 
  bool begin(Stream &stream);
  bool begin(FirmataTransport &transport);
 
  void begin() override;
  void begin(uint8_t address) override;  // I2C slave mode: unsupported, no-op
  void end() override;
 
  void setClock(uint32_t freq) override;  // no-op, see class note
 
  void beginTransmission(uint8_t address) override;
  size_t write(uint8_t data) override;
  size_t write(const uint8_t *data, size_t len) override;
  uint8_t endTransmission(bool stopBit) override;
  uint8_t endTransmission(void) override;
 
  size_t requestFrom(uint8_t address, size_t len, bool stopBit) override;
  size_t requestFrom(uint8_t address, size_t len) override;
 
  int available() override;
  int peek() override;
  int read() override;
  void flush() override {}
 
  void onReceive(void (*)(int)) override {}   // slave mode unsupported
  void onRequest(void (*)(void)) override {}  // slave mode unsupported
 
  void setTimeout(unsigned long timeout_ms) { timeout_ms_ = timeout_ms; }
 
  operator bool() { return is_open; }
 
 protected:
  FirmataTransport *transport_ = nullptr;             // non-owning
  std::unique_ptr<FirmataTransport> owned_transport_;  // set by begin(Stream&)
  bool is_open = false;
  unsigned long timeout_ms_ = 1000;
 
  uint8_t current_address_ = 0;
  std::vector<uint8_t> tx_buffer_;
 
  std::mutex rx_mutex_;
  std::condition_variable rx_cv_;
  std::deque<uint8_t> rx_buffer_;
  bool request_pending_ = false;
 
  void handleSysex(const FirmataSysexMessage &msg);
};
 
}  // namespace arduino
 
#endif  // USE_FIRMATA