import 'package:dart_periphery/dart_periphery.dart';

class Ads1256 {
  static const int RADD_STATUS = 0x00;
  static const int RADD_MUX = 0x01;
  static const int RADD_ADCON = 0x02;
  static const int RADD_DRATE = 0x03;
  static const int RADD_IO = 0x04;
  static const int RADD_OFC0 = 0x05;
  static const int RADD_OFC1 = 0x06;
  static const int RADD_OFC2 = 0x07;
  static const int RADD_FSC0 = 0x08;
  static const int RADD_FSC1 = 0x09;
  static const int RADD_FSC2 = 0x0A;

  static const int CMD_WAKEUP = 0x00;
  static const int CMD_RDATA = 0x01;
  static const int CMD_RDATAC = 0x03;
  static const int CMD_SDATAC = 0x0f;
  static const int CMD_RREG = 0x10;
  static const int CMD_WREG = 0x50;
  static const int CMD_SELFCAL = 0xF0;
  static const int CMD_SELFOCAL = 0xF1;
  static const int CMD_SELFGCAL = 0xF2;
  static const int CMD_SYSOCAL = 0xF3;
  static const int CMD_SYSGCAL = 0xF4;
  static const int CMD_SYNC = 0xFC;
  static const int CMD_STANDBY = 0xFD;
  static const int CMD_RESET = 0xFE;

  static const int MUXP_AIN0 = 0x00;
  static const int MUXP_AIN1 = 0x10;
  static const int MUXP_AIN2 = 0x20;
  static const int MUXP_AIN3 = 0x30;
  static const int MUXP_AIN4 = 0x40;
  static const int MUXP_AIN5 = 0x50;
  static const int MUXP_AIN6 = 0x60;
  static const int MUXP_AIN7 = 0x70;
  static const int MUXP_AINCOM = 0x80;

  static const int MUXN_AIN0 = 0x00;
  static const int MUXN_AIN1 = 0x01;
  static const int MUXN_AIN2 = 0x02;
  static const int MUXN_AIN3 = 0x03;
  static const int MUXN_AIN4 = 0x04;
  static const int MUXN_AIN5 = 0x05;
  static const int MUXN_AIN6 = 0x06;
  static const int MUXN_AIN7 = 0x07;
  static const int MUXN_AINCOM = 0x08;

  static const int GAIN_1 = 0x00;
  static const int GAIN_2 = 0x01;
  static const int GAIN_4 = 0x02;
  static const int GAIN_8 = 0x03;
  static const int GAIN_16 = 0x04;
  static const int GAIN_32 = 0x05;
  static const int GAIN_64 = 0x06;

  static const int DRATE_30000SPS = 0xF0;
  static const int DRATE_15000SPS = 0xE0;
  static const int DRATE_7500SPS = 0xD0;
  static const int DRATE_3750SPS = 0xC0;
  static const int DRATE_2000SPS = 0xB0;
  static const int DRATE_1000SPS = 0xA1;
  static const int DRATE_500SPS = 0x92;
  static const int DRATE_100SPS = 0x82;
  static const int DRATE_60SPS = 0x72;
  static const int DRATE_50SPS = 0x63;
  static const int DRATE_30SPS = 0x53;
  static const int DRATE_25SPS = 0x43;
  static const int DRATE_15SPS = 0x33;
  static const int DRATE_10SPS = 0x23;
  static const int DRATE_5SPS = 0x13;
  static const int DRATE_2_5SPS = 0x03;

  final SPI _spi; //SPI
  final GPIO _drdy; //GPIO
  final GPIO? _cs; //GPIO

  Ads1256(this._spi, this._drdy, this._cs) {}

  void _sendCommand(int reg) {
    _CSON();
    _waitDRDY();
    _spi.transfer([reg], false);
    _CSON();
  }

  void _writeRegister(int reg, int wdata) {
    _CSON();
    _spi.transfer([CMD_WREG, reg, 0, wdata], false);
    _CSOFF();
  }

  int _readRegister(int reg) {
    var val = _spi.transfer([CMD_RREG, 0, 0], true);
    return val[2];
  }

  void _waitDRDY() {
    while (_drdy.read()){}
  }

  void _CSON() {
    //PORT_CS &= ~(1 << PINDEX_CS);
    _cs?.write(false);
  }

  void _CSOFF() {
    //PORT_CS |= (1 << PINDEX_CS);
    _cs?.write(true);
  }

  void begin(int drate, int gain, bool buffen) {
    _sendCommand(
        CMD_SDATAC); // send out ADS1256_CMD_SDATAC command to stop continous reading mode.
    _writeRegister(RADD_DRATE, drate); // write data rate register
    int bytemask = 7;
    int adcon = _readRegister(RADD_ADCON);
    int byte2send = (adcon & ~bytemask) | gain;
    _writeRegister(RADD_ADCON, byte2send);
    if (buffen) {
      setBufferEnable(_readRegister(RADD_STATUS));
    }
    _sendCommand(CMD_SELFCAL); // perform self calibration
    _waitDRDY();
  }

  /*	STATUS : STATUS REGISTER (ADDRESS 00h)
      Reset Value = x1h
      Bit 3 ORDER: Data Output Bit Order
      0 = Most Significant Bit First (default)
      1 = Least Significant Bit First
      Bit 2 ACAL: Auto-Calibration
      0 = Auto-Calibration Disabled (default)
      1 = Auto-Calibration Enabled
      Bit 1 BUFEN: Analog Input Buffer Enable
      0 = Buffer Disabled (default)
      1 = Buffer Enabled
      Bit 0 DRDY: Data Ready (Read Only)
   */
  int getStatus() {
    _sendCommand(CMD_SDATAC);
    return _readRegister(RADD_STATUS);
  }

  void setBufferEnable(int status) {
    _writeRegister(RADD_STATUS, (status | (0x01 << 1)));
  }

  void resetBufferEnable(int status) {
    _writeRegister(RADD_STATUS, (status & ~(0x01 << 1)));
  }

  void readTest() {
    _CSON();
    var _hml =
        _spi.transfer([CMD_RDATA, CMD_WAKEUP, CMD_WAKEUP, CMD_WAKEUP], false);
    print(_hml);
    _CSOFF();
  }
  void dispose(){
    _spi.dispose(); //SPI
    _drdy.dispose(); //GPIO
    _cs?.dispose(); //GPIO
  }
}