#pragma once
// using external voltage reference

#include "esphome/core/component.h"
#include "esphome/components/spi/spi.h"
#include "esphome/components/sensor/sensor.h"

namespace esphome {
namespace ads131m08 {

typedef union {

    int32_t i;
    float f;
    uint16_t u[2];
    uint8_t b[4];
} flex32_t;


/* Adc Structure. Ch can be read as int32 or float*/
struct AdcOutput
{
  uint16_t status;
  flex32_t ch[8];
};

enum ADS131M08_DRDY_STATE
{
  DS_LOGIC_HIGH = 0, // DEFAULT
  DS_HI_Z = 1
};

enum ADS131M08_POWERMODE
{
  PM_VERY_LOW_POWER = 0,
  PM_LOW_POWER = 1,
  PM_HIGH_RESOLUTION = 2 // DEFAULT
};

enum ADS131M08_PGA_GAIN
{
  PGA_1 = 0,
  PGA_2 = 1,
  PGA_4 = 2,
  PGA_8 = 3,
  PGA_16 = 4,
  PGA_32 = 5,
  PGA_64 = 6,
  PGA_128 = 7,
  PGA_INVALID
};

enum ADS131M08_INPUT_CHANNEL_MUX
{
  ICM_AIN0P_AIN0N = 0, // DEFAULT
  ICM_INPUT_SHORTED = 1,
  ICM_POSITIVE_DC_TEST_SIGNAL = 2,
  ICM_NEGATIVE_DC_TEST_SIGNAL = 3,
};

enum ADS131M08_OVERSAMPLING_RATIO
{
  OSR_128 = 0,
  OSR_256 = 1,
  OSR_512 = 2,
  OSR_1024 = 3,      // default
  OSR_2048 = 4,
  OSR_4096 = 5,
  OSR_8192 = 6,
  OSR_16384 = 7
};

enum ADS131M08_WAIT_TIME
{
  WT_128 = 856,
  WT_256 = 1112,
  WT_512 = 1624,
  WT_1024 = 2648,
  WT_2048 = 4696,
  WT_4096 = 8792,
  WT_8192 = 16984,
  WT_16384 = 33368
};

// MODE Register
enum ADS131M08_RESET : uint16_t
{
  MODE_NO_RESET = 0x0000, // DEFAULT
  MODE_RESET_HAPPENED = 0x0400
};

enum ADS131M08_CRC_TYPE : uint16_t
{
  CRC_CCITT_16BIT = 0x0000, // DEFAULT
  CRC_ANSI_16BIT = 0x0800
};

enum ADS131M08_WORD_LENGTH : uint16_t
{
  WLENGTH_16_BITS = 0x0000,
  WLENGTH_24_BITS = 0x0100, // DEFAULT
  WLENGTH_32_BITS_LSB_ZERO_PADDING = 0x0200,  
  WLENGTH_32_BITS_MSB_SIGN_EXTEND = 0x0300
};

enum ADS131M08_TIMEOUT : uint16_t
{
  TIMEOUT_DISABLED = 0x0000, 
  TIMEOUT_ENABLED = 0x0010 // DEFAULT
};

enum ADS131M08_DRDY_SELECTION : uint16_t
{
  DRDY_SEL_MOST_LAGGING = 0x0000, // DEFAULT
  DRDY_SEL_LOGICAL_OR = 0x0004,
  DRDY_SEL_MOST_LEADING_CHAN = 0x0008,
  DRDY_SEL_MOST_LEADING_CHAN = 0x000C
};
enum ADS131M08_DRDY_FORMAT : uint16_t
{
  DRDY_FMT_LEVEL = 0x0000, // Logic low (default)
  DRDY_FMT_PULSE = 0x0001  // Low pulse with a fixed duration
};
// end of MODE Register

// GAIN1 Register 
enum ADS131M08_GAIN1_CHANNEL_PGA : uint16_t {
  PGAGAIN0_1 = 0x0000, // default
  PGAGAIN0_2 = 0x0001,
  PGAGAIN0_4 = 0x0002,
  PGAGAIN0_8 = 0x0003,
  PGAGAIN0_16 = 0x0004,
  PGAGAIN0_32 = 0x0005,
  PGAGAIN0_64 = 0x0006,
  PGAGAIN0_128 = 0x0007,
  PGAGAIN1_1 = 0x0000, // default
  PGAGAIN1_2 = 0x0010,
  PGAGAIN1_4 = 0x0020, 
  PGAGAIN1_8 = 0x0030,
  PGAGAIN1_16 = 0x0040,
  PGAGAIN1_32 = 0x0050,
  PGAGAIN1_64 = 0x0060,
  PGAGAIN1_128 = 0x0070,
  PGAGAIN2_1 = 0x0000, // default
  PGAGAIN2_2 = 0x0100,
  PGAGAIN2_4 = 0x0200,
  PGAGAIN2_8 = 0x0300,
  PGAGAIN2_16 = 0x0400,
  PGAGAIN2_32 = 0x0500,
  PGAGAIN2_64 = 0x0600,
  PGAGAIN2_128 = 0x0700,
  PGAGAIN3_1 = 0x0000, // default
  PGAGAIN3_2 = 0x1000,
  PGAGAIN3_4 = 0x2000,
  PGAGAIN3_8 = 0x3000,
  PGAGAIN3_16 = 0x4000,
  PGAGAIN3_32 = 0x5000, // Set PGA gain to 32 for channel 
  PGAGAIN3_64 = 0x6000,
  PGAGAIN3_128 = 0x7000
};
// end of GAIN1 Register

// GAIN2 Register 
enum ADS131M08_GAIN2_CHANNEL_PGA : uint16_t {
  PGAGAIN4_1 = 0x0000, // default
  PGAGAIN4_2 = 0x0001,
  PGAGAIN4_4 = 0x0002,
  PGAGAIN4_8 = 0x0003,
  PGAGAIN4_16 = 0x0004,
  PGAGAIN4_32 = 0x0005,
  PGAGAIN4_64 = 0x0006,
  PGAGAIN4_128 = 0x0007,
  PGAGAIN5_1 = 0x0000, // default
  PGAGAIN5_2 = 0x0010,
  PGAGAIN5_4 = 0x0020, 
  PGAGAIN5_8 = 0x0030,
  PGAGAIN5_16 = 0x0040,
  PGAGAIN5_32 = 0x0050,
  PGAGAIN5_64 = 0x0060,
  PGAGAIN5_128 = 0x0070,
  PGAGAIN6_1 = 0x0000, // default
  PGAGAIN6_2 = 0x0100,
  PGAGAIN6_4 = 0x0200,
  PGAGAIN6_8 = 0x0300,
  PGAGAIN6_16 = 0x0400,
  PGAGAIN6_32 = 0x0500,
  PGAGAIN6_64 = 0x0600,
  PGAGAIN6_128 = 0x0700,
  PGAGAIN7_1 = 0x0000, // default
  PGAGAIN7_2 = 0x1000,
  PGAGAIN7_4 = 0x2000,
  PGAGAIN7_8 = 0x3000,
  PGAGAIN7_16 = 0x4000,
  PGAGAIN7_32 = 0x5000,
  PGAGAIN7_64 = 0x6000,
  PGAGAIN7_128 = 0x7000
};
// end of GAIN2 Register


// Commands
enum ADS131M08_COMMANDS : uint16_t {
  CMD_NULL = 0x0000,    // No operation; used to read STATUS register
  CMD_RESET = 0x0011,   // RESET the device
  CMD_STANDBY = 0x0022, // Place the device into standby mode
  CMD_WAKEUP = 0x0033,  // Wake up device from standby mode to conversion mode
  CMD_LOCK = 0x0555,    // Lock the interface such that only the NULL, UNLOCK, and RREG commands are valid
  CMD_UNLOCK = 0x0655,  // Unlock the interface after the interface is locked
  CMD_RREG = 0xA000,    // Read register command base; number of registers to read added to lower byte; register address to upper byte
  CMD_WREG = 0x6000,    // Write register command base; number of registers to write added to lower byte; register address to upper byte
};

// Responses
enum ADS131M08_RESPONSES : uint16_t {
  RSP_RESET_OK = 0xFF28,
  RSP_RESET_NOK = 0x0011
};

enum ADS131M08_REG {
  REG_ID = 0x00,
  REG_STATUS = 0x01,
  REG_MODE = 0x02,
  REG_CLOCK = 0x03,
  REG_GAIN1 = 0x04,
  REG_GAIN2 = 0x05,
  REG_CFG = 0x06,
  REG_THRSHLD_MSB = 0x07,
  REG_THRSHLD_LSB = 0x08,
  REG_CH0_CFG = 0x09,
  REG_CH0_OCAL_MSB = 0x0A,
  REG_CH0_OCAL_LSB = 0x0B,
  REG_CH0_GCAL_MSB = 0x0C,
  REG_CH0_GCAL_LSB = 0x0D,
  REG_CH1_CFG = 0x0E,
  REG_CH1_OCAL_MSB = 0x0F,
  REG_CH1_OCAL_LSB = 0x10,
  REG_CH1_GCAL_MSB = 0x11,
  REG_CH1_GCAL_LSB = 0x12,
  REG_CH2_CFG = 0x13,
  REG_CH2_OCAL_MSB= 0x14,
  REG_CH2_OCAL_LSB= 0x15,
  REG_CH2_GCAL_MSB= 0x16,
  REG_CH2_GCAL_LSB= 0x17,
  REG_CH3_CFG = 0x18,
  REG_CH3_OCAL_MSB= 0x19,
  REG_CH3_OCAL_LSB= 0x1A,
  REG_CH3_GCAL_MSB= 0x1B,
  REG_CH3_GCAL_LSB= 0x1C,
  REG_CH4_CFG = 0x1D,
  REG_CH4_OCAL_MSB= 0x1E,
  REG_CH4_OCAL_LSB= 0x1F,
  REG_CH4_GCAL_MSB= 0x20,
  REG_CH4_GCAL_LSB= 0x21,
  REG_CH5_CFG = 0x22,
  REG_CH5_OCAL_MSB= 0x23,
  REG_CH5_OCAL_LSB= 0x24,
  REG_CH5_GCAL_MSB= 0x25,
  REG_CH5_GCAL_LSB= 0x26,
  REG_CH6_CFG = 0x27,
  REG_CH6_OCAL_MSB= 0x28,
  REG_CH6_OCAL_LSB= 0x29,
  REG_CH6_GCAL_MSB= 0x2A,
  REG_CH6_GCAL_LSB= 0x2B,
  REG_CH7_CFG = 0x2C,
  REG_CH7_OCAL_MSB= 0x2D,
  REG_CH7_OCAL_LSB= 0x2E,
  REG_CH7_GCAL_MSB= 0x2F,
  REG_CH7_GCAL_LSB= 0x30,
  REGMAP_CRC = 0x3E,
  };
// Mask READ_REG
static constexpr uint16_t MASK_CMD_READ_REG_ADDRESS = 0x1F80;
static constexpr uint16_t MASK_CMD_READ_REG_BYTES = 0x007F;

// Mask Register STATUS
static constexpr uint16_t MASK_STATUS_LOCK = 0x8000;
static constexpr uint16_t MASK_STATUS_RESYNC = 0x4000;
static constexpr uint16_t MASK_STATUS_REGMAP = 0x2000;
static constexpr uint16_t MASK_STATUS_CRC_ERR = 0x1000;
static constexpr uint16_t MASK_STATUS_CRC_TYPE = 0x0800;
static constexpr uint16_t MASK_STATUS_RESET = 0x0400;
static constexpr uint16_t MASK_STATUS_WLENGTH = 0x0300;
static constexpr uint16_t MASK_STATUS_DRDY7 = 0x0080;
static constexpr uint16_t MASK_STATUS_DRDY6 = 0x0040;
static constexpr uint16_t MASK_STATUS_DRDY5 = 0x0020;
static constexpr uint16_t MASK_STATUS_DRDY4 = 0x0010;
static constexpr uint16_t MASK_STATUS_DRDY3 = 0x0008;
static constexpr uint16_t MASK_STATUS_DRDY2 = 0x0004;
static constexpr uint16_t MASK_STATUS_DRDY1 = 0x0002;
static constexpr uint16_t MASK_STATUS_DRDY0 = 0x0001;

// Mask Register MODE
static constexpr uint16_t MASK_MODE_REG_CRC_EN = 0x2000;
static constexpr uint16_t MASK_MODE_RX_CRC_EN = 0x1000;
static constexpr uint16_t MASK_MODE_CRC_TYPE = 0x0800;
static constexpr uint16_t MASK_MODE_RESET = 0x0400;
static constexpr uint16_t MASK_MODE_WLENGTH = 0x0300;
static constexpr uint16_t MASK_MODE_TIMEOUT = 0x0010;
static constexpr uint16_t MASK_MODE_DRDY_SEL = 0x000C;
static constexpr uint16_t MASK_MODE_DRDY_HiZ = 0x0002;
static constexpr uint16_t MASK_MODE_DRDY_FMT = 0x0001;

// Mask Register CLOCK
static constexpr uint16_t MASK_CLOCK_CH7_EN = 0x8000;
static constexpr uint16_t MASK_CLOCK_CH6_EN = 0x4000;
static constexpr uint16_t MASK_CLOCK_CH5_EN = 0x2000;
static constexpr uint16_t MASK_CLOCK_CH4_EN = 0x1000;
static constexpr uint16_t MASK_CLOCK_CH3_EN = 0x0800;
static constexpr uint16_t MASK_CLOCK_CH2_EN = 0x0400;
static constexpr uint16_t MASK_CLOCK_CH1_EN = 0x0200;
static constexpr uint16_t MASK_CLOCK_CH0_EN = 0x0100;
static constexpr uint16_t MASK_CLOCK_OSR = 0x001C;
static constexpr uint16_t MASK_CLOCK_PWR = 0x0003;
static constexpr uint32_t MASK_CLOCK_ALL_CH_DISABLE = 0x0000;
static constexpr uint32_t MASK_CLOCK_ALL_CH_ENABLE = 0xFF00;
// Mask Register GAIN
static constexpr uint16_t MASK_GAIN_PGAGAIN7 = 0x7000;
static constexpr uint16_t MASK_GAIN_PGAGAIN6 = 0x0700;
static constexpr uint16_t MASK_GAIN_PGAGAIN5 = 0x0070;
static constexpr uint16_t MASK_GAIN_PGAGAIN4 = 0x0007;
static constexpr uint16_t MASK_GAIN_PGAGAIN3 = 0x7000;
static constexpr uint16_t MASK_GAIN_PGAGAIN2 = 0x0700;
static constexpr uint16_t MASK_GAIN_PGAGAIN1 = 0x0070;
static constexpr uint16_t MASK_GAIN_PGAGAIN0 = 0x0007;

// Mask Register CFG
static constexpr uint16_t MASK_CFG_GC_DLY = 0x1E00;
static constexpr uint16_t MASK_CFG_GC_EN = 0x0100;
static constexpr uint16_t MASK_CFG_CD_ALLCH = 0x0080;
static constexpr uint16_t MASK_CFG_CD_NUM = 0x0070;
static constexpr uint16_t MASK_CFG_CD_LEN = 0x000E;
static constexpr uint16_t MASK_CFG_CD_EN = 0x0001;

// Mask Register THRSHLD_MSB - dummy, for completeness
static constexpr uint16_t MASK_THRSHLD_MSB_CD_TH_MSB = 0xFFFF;

// Mask Register THRSHLD_LSB
static constexpr uint16_t MASK_THRSHLD_LSB_CD_TH_LSB = 0xFF00;
static constexpr uint16_t MASK_THRSHLD_LSB_DCBLOCK = 0x000F;

// Mask Register CHX_CFG
static constexpr uint16_t MASK_CHX_CFG_PHASE = 0xFFC0;
static constexpr uint16_t MASK_CHX_CFG_DCBLKX_DIS = 0x0004;
static constexpr uint16_t MASK_CHX_CFG_MUX = 0x0003;

// Mask Register CHX_OCAL_MSB - dummy, for completeness
static constexpr uint16_t MASK_CHX_OCAL_MSB = 0xFFFF;

// Mask Register CHX_OCAL_LSB
static constexpr uint16_t MASK_CHX_OCAL_LSB = 0xFF00;

// Mask Register CHX_GCAL_MSB - dummy, for completeness
static constexpr uint16_t MASK_CHX_GCAL_MSB = 0xFFFF;

// Mask Register CHX_GCAL_LSB
static constexpr uint16_t MASK_CHX_GCAL_LSB = 0xFF00;

//   --------------------------------------------------------------------

// Conversion modes
static constexpr uint16_t CONVERSION_MODE_CONT = 0;
static constexpr uint16_t CONVERSION_MODE_SINGLE = 1;

// Data Format
static constexpr uint16_t DATA_FORMAT_TWO_COMPLEMENT = 0;
static constexpr uint16_t DATA_FORMAT_BINARY = 1;

// Measure Mode
static constexpr uint8_t MEASURE_UNIPOLAR = 1;
static constexpr uint8_t MEASURE_BIPOLAR = 0;

// Clock Type
static constexpr uint8_t CLOCK_EXTERNAL = 1;
static constexpr uint8_t CLOCK_INTERNAL = 0;

// PGA Gain
// static constexpr uint16_t PGA_GAIN_1 = 0;
// static constexpr uint16_t PGA_GAIN_2 = 1;
// static constexpr uint16_t PGA_GAIN_4 = 2;
// static constexpr uint16_t PGA_GAIN_8 = 3;
// static constexpr uint16_t PGA_GAIN_16 = 4;
// static constexpr uint16_t PGA_GAIN_32 = 5;
// static constexpr uint16_t PGA_GAIN_64 = 6;
// static constexpr uint16_t PGA_GAIN_128 = 7;

// Input Filter
static constexpr uint16_t FILTER_SYNC = 0;
static constexpr uint16_t FILTER_FIR = 2;
static constexpr uint16_t FILTER_FIR_IIR = 3;

// Data Mode
static constexpr uint8_t DATA_MODE_24BITS = 0;
static constexpr uint8_t DATA_MODE_32BITS = 1;

// Data Rate
static constexpr uint8_t DATA_RATE_0 = 0;
static constexpr uint8_t DATA_RATE_1 = 1;
static constexpr uint8_t DATA_RATE_2 = 2;
static constexpr uint8_t DATA_RATE_3 = 3;
static constexpr uint8_t DATA_RATE_4 = 4;
static constexpr uint8_t DATA_RATE_5 = 5;
static constexpr uint8_t DATA_RATE_6 = 6;
static constexpr uint8_t DATA_RATE_7 = 7;
static constexpr uint8_t DATA_RATE_8 = 8;
static constexpr uint8_t DATA_RATE_9 = 9;
static constexpr uint8_t DATA_RATE_10 = 10;
static constexpr uint8_t DATA_RATE_11 = 11;
static constexpr uint8_t DATA_RATE_12 = 12;
static constexpr uint8_t DATA_RATE_13 = 13;
static constexpr uint8_t DATA_RATE_14 = 14;
static constexpr uint8_t DATA_RATE_15 = 15;
// Sync Mpdes
static constexpr uint16_t SYNC_CONTINUOUS = 1;
static constexpr uint16_t SYNC_PULSE = 0;

// DIO Config Mode
static constexpr uint8_t DIO_OUTPUT = 1;
static constexpr uint8_t DIO_INPUT = 0;

static constexpr uint8_t SPI_MASTER_DUMMY = 0xFF;
static constexpr uint16_t SPI_MASTER_DUMMY16 = 0xFFFF;
static constexpr uint32_t SPI_MASTER_DUMMY32 = 0xFFFFFFFF;


// end of from datasheet

class ADS131M08Sensor : public sensor::Sensor, public Component 
{
};

class ADS131M08Hub : public Component, public spi::SPIDevice<spi::BIT_ORDER_MSB_FIRST, spi::CLOCK_POLARITY_LOW, spi::CLOCK_PHASE_TRAILING, spi::DATA_RATE_8MHZ> 
{
 public:
 // from datasheet pg. 93:
  const int numFrameWords = 10;      // Number of words in a full ADS131M08 SPI frame 
  unsigned long spiDummyWord[10 /*numFrameWords*/] = {
    0x00000000,
    0x00000000,
    0x00000000,
    0x00000000,
    0x00000000,
    0x00000000,
    0x00000000,
    0x00000000,
    0x00000000,
    0x00000000
  };    // Dummy word frame to write ADC during ADC data reads
  bool firstRead = true;  // Flag to tell us if we are reading ADC data for the first time 
  signed long adcData;    // Location where DMA will store ADC data in memory, length defined elsewhere
  void txf_init();
  bool adcRegisterWrite(unsigned short addrMask, unsigned short data, unsigned char adcWordLength);
  void initialize_ads131m08_datasheet();
  // end of from datasheet

  bool setChannelPGA(uint8_t channel, uint8_t pga);
  void setup() override;
  void loop() override;
  void set_drdy_pin(InternalGPIOPin *pin) { drdy_pin_ = pin; }
  void register_sensor(int channel, ADS131M08Sensor *s) { sensors_[channel] = s; }
  void set_reference_voltage(float reference_voltage) { this->reference_voltage_ = reference_voltage; }  
  void dump_config() override;

  // from tpcorrea
  void begin(uint8_t clk_pin, uint8_t miso_pin, uint8_t mosi_pin, uint8_t cs_pin, uint8_t drdy_pin,  uint8_t reset_pin);
  int8_t isDataReadySoft(uint8_t channel);
  bool isDataReady(void);
  bool isResetStatus(void);
  bool isLockSPI(void);
  bool setDrdyFormat(uint8_t drdyFormat);
  bool setDrdyStateWhenUnavailable(uint8_t drdyState);
  bool setPowerMode(uint8_t powerMode);
  bool setChannelEnable(uint8_t channel, uint16_t enable);
  bool setChannelPGA(uint8_t channel, ADS131M08_PGA_GAIN pga);
  ADS131M08_PGA_GAIN getChannelPGA(uint8_t channel);
  void setGlobalChop(uint16_t global_chop);
  void setGlobalChopDelay(uint16_t delay);
  bool setInputChannelSelection(uint8_t channel, uint8_t input);
  bool setChannelOffsetCalibration(uint8_t channel, int32_t offset);
  bool setChannelGainCalibration(uint8_t channel, uint32_t gain);
  bool setOsr(uint16_t osr);
  void setFullScale(uint8_t channel, float scale);
  float getFullScale(uint8_t channel);
  void reset();
  uint16_t getId();
  uint16_t getModeReg();
  uint16_t getClockReg();
  uint16_t getCfgReg();
  AdcOutput readAdcRaw(void);
  AdcOutput readAdcFloat(void);

 protected:
  float reference_voltage_; 
  InternalGPIOPin *drdy_pin_;
  ADS131M08Sensor *sensors_[8] = {nullptr};
  volatile bool data_ready_{false};
  static void isr(ADS131M08Hub *arg);
  void read_data_();
  void write_register(uint8_t reg, uint16_t value);

};

} // namespace ads131m08
} // namespace esphome