/*********************************************************************************
 *
 *  lora_aprs_node_pico is a LoRa APRS KISS modem with additional PE1RXF telemetry
 *  capabilities. It runs on a Raspberry Pi Pico.
 *
 * (C)2023 M.T. Konstapel https://meezenest.nl/mees
 *
 * This file is part of lora_aprs_node_pico.
 *
 *    lora_aprs_node_pico is free software: you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation, either version 3 of the License, or
 *    (at your option) any later version.
 *
 *    lora_aprs_node_pico 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 General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with lora_aprs_node_pico. If not, see <https://www.gnu.org/licenses/>.
 *
 **********************************************************************************/
#ifndef LORA_H
#define LORA_H

// // #include <Arduino.h>
// #include <SPI.h>

#include "pico/stdlib.h"
#include "pico/binary_info.h"
#include "hardware/gpio.h"
#include "hardware/spi.h"
#include "string.h"
#include "Print.h"

#define PIN_MISO 16
#define PIN_CS   8
#define PIN_SCK  18
#define PIN_MOSI 19

#define SPI_PORT spi0
#define READ_BIT 0x80

#define LORA_DEFAULT_SPI           spi0
#define LORA_DEFAULT_SPI_FREQUENCY 8E6
#define LORA_DEFAULT_SS_PIN        8
#define LORA_DEFAULT_RESET_PIN     11
#define LORA_DEFAULT_DIO0_PIN      10
#define LORA_DEFAULT_DIO1_PIN      9
#endif

#define PA_OUTPUT_RFO_PIN          0
#define PA_OUTPUT_PA_BOOST_PIN     1

static void __empty();

//class LoRaClass : public Stream {
class LoRaClass : public Print {
public:
  LoRaClass();

  int begin(long frequency);
  void end();

  int beginPacket(int implicitHeader = false);
  int endPacket(bool async = false);

  int parsePacket(int size = 0);
  int packetRssi();
  float packetSnr();
  long packetFrequencyError();

  int rssi();

  // from Print
  virtual size_t write(uint8_t byte);
  virtual size_t write(const uint8_t *buffer, size_t size);

  // from Stream
  virtual int available();
  virtual int read();
  virtual int peek();
  virtual void flush();


  void onReceive(void(*callback)(int));
  void onTxDone(void(*callback)());

  void receive(int size = 0);

  void idle();
  void sleep();

  // size_t print(const char* c);

  void setTxPower(int level, int outputPin = PA_OUTPUT_PA_BOOST_PIN);
  void setFrequency(long frequency);
  void setSpreadingFactor(int sf);
  void setSignalBandwidth(long sbw);
  void setCodingRate4(int denominator);
  void setPreambleLength(long length);
  void setSyncWord(int sw);
  void enableCrc();
  void disableCrc();
  void enableInvertIQ();
  void disableInvertIQ();
  
  void setOCP(uint8_t mA); // Over Current Protection control
  
  void setGain(uint8_t gain); // Set LNA gain

  // deprecated
  void crc() { enableCrc(); }
  void noCrc() { disableCrc(); }

  uint8_t random();

  void setPins(int ss = LORA_DEFAULT_SS_PIN, int reset = LORA_DEFAULT_RESET_PIN, int dio0 = LORA_DEFAULT_DIO0_PIN);
  void setSPI(spi_inst_t& spi);
  void setSPIFrequency(uint32_t frequency);

  void dumpRegisters();

private:
  void explicitHeaderMode();
  void implicitHeaderMode();

  void handleDio0Rise();
  bool isTransmitting();

  int getSpreadingFactor();
  long getSignalBandwidth();

  void setLdoFlag();

  uint8_t readRegister(uint8_t address);
  void writeRegister(uint8_t address, uint8_t value);
  uint8_t singleTransfer(uint8_t address, uint8_t value);

  static void onDio0Rise(uint, uint32_t);

private:
  // SPISettings _spiSettings;
  spi_inst_t* _spi;
  int _ss;
  int _reset;
  int _dio0;
  long _frequency;
  int _packetIndex;
  int _implicitHeaderMode;
  void (*_onReceive)(int);
  void (*_onTxDone)();
};

extern LoRaClass LoRa;

// #endif