#include <Arduino.h>
#if defined(LINUX_ARCH_RASPBERRYPI)
#include <wiringPi.h>
#include <wiringPiSPI.h>
#elif defined(ARDUINO_ARCH_ESP8266) || defined(ARDUINO_ARCH_ESP32)
#include <SPI.h>
#endif

#include "cc1101.h"

static const uint8_t cc1101_init[] = {
  // IDX NAME     RESET   COMMENT
  0x2E,  // 00 IOCFG2    29     Tri-State
  0x2E,  // 01 IOCFG1           Tri-State
  0x2E,  // 02 IOCFG0    3F     GDO0 for input
  0x47,  // 03 FIFOTHR          RX filter bandwidth = 325 kHz, FIFOTHR = 0x47
  0xD3,  // 04 SYNC1
  0x91,  // 05 SYNC0
  0x3D,  // 06 PKTLEN    0F
  0x04,  // 07 PKTCTRL1
  0x32,  // 08 PKTCTRL0  45
  0x00,  // 09 ADDR
  0x00,  // 0A CHANNR
  0x06,  // 0B FSCTRL1   0F     152kHz IF Frquency
  0x00,  // 0C FSCTRL0
  0x10,  // 0D FREQ2     1E     Freq   #12  Reg Pos 0C
  0xB0,  // 0E FREQ1     C4        Reg Pos 0D
  0x71,  // 0F FREQ0     EC        Reg Pos 0E
  0x57,  // 10 MDMCFG4   8C     bWidth 325kHz
  0xC4,  // 11 MDMCFG3   22     DataRate
  0x30,  // 12 MDMCFG2   02     Modulation: ASK
  0x23,  // 13 MDMCFG1   22
  0xb9,  // 14 MDMCFG0   F8     ChannelSpace: 350kHz
  0x00,  // 15 DEVIATN   47
  0x07,  // 16 MCSM2     07
  0x00,  // 17 MCSM1     30     Bit 3:2  RXOFF_MODE:  Select what should happen when a packet has been received: 0 = IDLE  3 =  Stay in RX ####
  0x18,  // 18 MCSM0     04     Calibration: RX/TX->IDLE
  0x14,  // 19 FOCCFG    36
  0x6C,  // 1A BSCFG
  0x07,  // 1B AGCCTRL2  03     42 dB instead of 33dB
  0x00,  // 1C AGCCTRL1  40
  0x91,  // 1D AGCCTRL0  91     8dB decision boundery
  0x87,  // 1E WOREVT1
  0x6B,  // 1F WOREVT0
  0xF8,  // 20 WORCTRL
  0xB6,  // 21 FREND1    B6     RX filter bandwidth > 101 kHz, FREND1 = 0xB6
  0x11,  // 22 FREND0    16     0x11 for no PA ramping
  0xE9,  // 23 FSCAL3    A9    E9 ??
  0x2A,  // 24 FSCAL2    0A
  0x00,  // 25 FSCAL1    20    19 ??
  0x1F,  // 26 FSCAL0    0D
  0x41,  // 27 RCCTRL1
  0x00,  // 28 RCCTRL0
};

static const uint8_t patable_power_315[8] = { 0x17, 0x1D, 0x26, 0x69, 0x51, 0x86, 0xCC, 0xC3 };
static const uint8_t patable_power_434[8] = { 0x6C, 0x1C, 0x06, 0x3A, 0x51, 0x85, 0xC8, 0xC0 };
static const uint8_t patable_power_868[8] = { 0x00, 0x17, 0x1D, 0x26, 0x50, 0x86, 0xCD, 0xC0 };
static const uint8_t patable_power_915[8] = { 0x0B, 0x1B, 0x6D, 0x67, 0x50, 0x85, 0xC9, 0xC1 };

// 5 dB default value for factory reset
static const uint8_t patable_power_ook[8] = { 0x00, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };

enum MarcState
  : uint8_t
{
  STATE_SLEEP            = 0x00,
  STATE_IDLE             = 0x01,
  STATE_XOFF             = 0x02,
  STATE_VCOON_MC         = 0x03,
  STATE_REGON_MC         = 0x04,
  STATE_MANCAL           = 0x05,
  STATE_VCOON            = 0x06,
  STATE_REGCON           = 0x07,
  STATE_STARTCAL         = 0x08,
  STATE_BWBOOST          = 0x09,
  STATE_FS_LOCK          = 0x0A,
  STATE_IFADCON          = 0x0B,
  STATE_ENDCAL           = 0x0C,
  STATE_RX               = 0x0D,
  STATE_RX_END           = 0x0E,
  STATE_TX_RST           = 0x0F,
  STATE_TXRX_SWITCH      = 0x10,
  STATE_RXFIFO_OVERFLOW  = 0x11,
  STATE_FSTXON           = 0x12,
  STATE_TX               = 0x13,
  STATE_TX_END           = 0x14,
  STATE_RXTX_SWITCH      = 0x15,
  STATE_TXFIFO_UNDERFLOW = 0x16,
  STATE_MASK             = 0x1F,
};

CC1101::~CC1101()
{
  if (_init_done)
    (void)idle();
}

#if !defined(LINUX_ARCH_RASPBERRYPI)
void CC1101::set_spi_pins(uint8_t mosi, uint8_t miso, uint8_t sck)
{
  _mosi = mosi;
  _miso = miso;
  _sck  = sck;
}

void CC1101::select()
{
  digitalWrite(_ss, LOW);
}

void CC1101::deselect()
{
  digitalWrite(_ss, HIGH);
}

bool CC1101::wait_MISO()
{
  uint8_t miso_count = 255;
  while(digitalRead(_miso) == HIGH && miso_count > 0)
    --miso_count;
  return (miso_count > 0);
}

uint8_t CC1101::spi_putc(const uint8_t value)
{
#if defined(ARDUINO_ARCH_ESP8266) || defined(ARDUINO_ARCH_ESP32)
  return SPI.transfer(value);
#else
  SPDR = value;
  asm volatile("nop");
  while(!(SPSR & _BV(SPIF)));
  return SPDR;
#endif
}
#endif

bool CC1101::spi_begin()
{
#if defined(LINUX_ARCH_RASPBERRYPI)
  //4MHz SPI speed
  return (wiringPiSPISetup(0, 4000000) >= 0);
#elif defined(ARDUINO_ARCH_ESP8266) || defined(ARDUINO_ARCH_ESP32)
  pinMode(_ss, OUTPUT);
  deselect();

  SPI.setDataMode(SPI_MODE0);
  SPI.setBitOrder(MSBFIRST);
  SPI.begin();
  SPI.setClockDivider(SPI_CLOCK_DIV4);
#else
  pinMode(_ss, OUTPUT);
  deselect();

  pinMode(_sck,  OUTPUT);
  pinMode(_mosi, OUTPUT);
  pinMode(_miso, INPUT);

  // SPI init
  SPCR = _BV(SPE) | _BV(MSTR);  // SPI speed = CLK/4
  digitalWrite(_sck,  HIGH);
  digitalWrite(_mosi, LOW);
#endif
  return true;
}

void CC1101::spi_write_register(Register spi_instr, uint8_t value)
{
#if defined(LINUX_ARCH_RASPBERRYPI)
  uint8_t tbuf[2] = {0};
  tbuf[0] = spi_instr | WRITE_SINGLE_BYTE;
  tbuf[1] = value;
  wiringPiSPIDataRW(0, tbuf, 2);
#else
  select();
  wait_MISO();
  spi_putc(spi_instr | WRITE_SINGLE_BYTE);
  spi_putc(value);
  deselect();
#endif
}

uint8_t CC1101::spi_read_register(Register spi_instr)
{
#if defined(LINUX_ARCH_RASPBERRYPI)
  uint8_t rbuf[2] = {0};
  rbuf[0] = spi_instr | READ_SINGLE_BYTE;
  wiringPiSPIDataRW(0, rbuf, 2);
  return rbuf[1];
#else
  select();
  wait_MISO();
  spi_putc(spi_instr | READ_SINGLE_BYTE);
  uint8_t ret = spi_putc(0x00);
  deselect();
  return ret;
#endif
}

uint8_t CC1101::spi_write_strobe(Strobe spi_instr)
{
#if defined(LINUX_ARCH_RASPBERRYPI)
  uint8_t tbuf[1] = {0};
  tbuf[0] = spi_instr;
  wiringPiSPIDataRW(0, tbuf, 1);
  return tbuf[0];
#else
  select();
  wait_MISO();
  uint8_t ret = spi_putc(spi_instr);
  wait_MISO();
  deselect();
  return ret;
#endif
}

void CC1101::spi_read_burst(SPI_RW spi_instr, uint8_t *pArr, uint8_t len)
{
#if defined(LINUX_ARCH_RASPBERRYPI)
  uint8_t rbuf[len + 1];
  rbuf[0] = spi_instr | READ_BURST;
  wiringPiSPIDataRW(0, rbuf, len + 1);
  for (uint8_t i = 0; i < len ;i++ )
    pArr[i] = rbuf[i + 1];
#else
  select();
  wait_MISO();
  spi_putc(spi_instr | READ_BURST);
  for (uint8_t i = 0; i < len ;i++ )
    pArr[i] = spi_putc(0x00);
  deselect();
#endif
}

void CC1101::spi_write_burst(SPI_RW spi_instr, const uint8_t *pArr, uint8_t len)
{
#if defined(LINUX_ARCH_RASPBERRYPI)
  uint8_t tbuf[len + 1];
  tbuf[0] = spi_instr | WRITE_BURST;
  for (uint8_t i = 0; i < len; i++)
    tbuf[i + 1] = pArr[i];
  wiringPiSPIDataRW(0, tbuf, len + 1);
#else
  select();
  wait_MISO();
  spi_putc(spi_instr | WRITE_BURST);
  for (uint8_t i = 0; i < len; i++)
    spi_putc(pArr[i]);
  deselect();
#endif
}

bool CC1101::setup()
{
#if defined(LINUX_ARCH_RASPBERRYPI)
  wiringPiSetup();
#endif
  pinMode(_gdo0, OUTPUT);
  digitalWrite(_gdo0, LOW);
  pinMode(_gdo2, INPUT);

  spi_begin();
  reset();

  //uint8_t partnum = spi_read_register(PARTNUM);
  uint8_t version = spi_read_register(VERSION);
  //checks if valid Chip ID is found. Usualy 0x03 or 0x14. if not -> abort
  if (version == 0x00 || version == 0xFF)
    return false;

  spi_write_burst(WRITE_BURST, cc1101_init, sizeof(cc1101_init));
  if (!register_check())
    return false;
  _init_done = true;
  return true;
}

bool CC1101::setISM(CC1101::ISM_FREQ ism_freq)
{
  uint8_t freq2, freq1, freq0;
  const uint8_t *patable = patable_power_ook;
  switch(ism_freq)
  {
    case CC1101::FREQ_315MHZ:
      freq2 = 0x0C;
      freq1 = 0x1D;
      freq0 = 0x89;
      //patable = patable_power_315;
      break;
    case CC1101::FREQ_434MHZ:
      freq2 = 0x10;
      freq1 = 0xB0;
      freq0 = 0x71;
      //patable = patable_power_434;
      break;
    case CC1101::FREQ_868MHZ:
      freq2 = 0x21;
      freq1 = 0x65;
      freq0 = 0x6A;
      //patable = patable_power_868;
      break;
    case CC1101::FREQ_915MHZ:
      freq2 = 0x23;
      freq1 = 0x31;
      freq0 = 0x3B;
      //patable = patable_power_915;
      break;
    /*
    case CC1101::FREQ_2430MHZ:
      freq2 = 0x5D;
      freq1 = 0x76;
      freq0 = 0x27;
      //patable = patable_power_2430;
      break;
    */
    default:
      return false;
  }

  setPatable(patable);

  // stores the new freq setting for defined ISM band
  spi_write_register(FREQ2, freq2);
  spi_write_register(FREQ1, freq1);
  spi_write_register(FREQ0, freq0);

  return true;
}

void CC1101::setPatable(const uint8_t patable[8])
{
  spi_write_burst(PATABLE_BURST, patable, 8);
}

bool CC1101::register_check()
{
  return (spi_read_register(PKTCTRL0) == cc1101_init[PKTCTRL0]
    && spi_read_register(IOCFG2) == cc1101_init[IOCFG2]);
}

bool CC1101::transmit()
{
  idle();
  setGDO0(LOW);
  spi_write_strobe(STX);
  uint8_t maxloop = 255;
  while (--maxloop && (spi_read_register(MARCSTATE) & STATE_MASK) != STATE_TX)
    delay(1);
  return (maxloop != 0);
}

void CC1101::setGDO0(int value)
{
  digitalWrite(_gdo0, value);
}

bool CC1101::receive()
{
  idle();
  spi_write_strobe(SRX);
  uint8_t maxloop = 255;
  while (--maxloop && (spi_read_register(MARCSTATE) & STATE_MASK) != STATE_RX)
    delay(1);
  return (maxloop != 0);
}

void CC1101::wakeup()
{
  digitalWrite(_ss, LOW);
  delayMicroseconds(10);
  digitalWrite(_ss, HIGH);
  delayMicroseconds(10);
  idle();
}

void CC1101::powerdown()
{
  idle();
  spi_write_strobe(SPWD);
}

void CC1101::idle()
{
  spi_write_strobe(SIDLE);
  uint8_t maxloop = 0xff;
  while (--maxloop && (spi_read_register(MARCSTATE) & STATE_MASK) != STATE_IDLE)
    delay(1);
  delayMicroseconds(100);
}

void CC1101::reset(void)
{
  digitalWrite(_ss, LOW);
  delayMicroseconds(10);
  digitalWrite(_ss, HIGH);
  delayMicroseconds(40);

  spi_write_strobe(SRES);
  delay(1);
}