#ifndef _PMS7003_H_
#define _PMS7003_H_

#include <Arduino.h>

#define PMS7003_DATA_SIZE 32   // 0x42 + 0x4d  + 28 bytes data + 2 bytes checksum = 32 bytes

typedef struct pms7003_struct {
  uint8_t start_1;          // Start char 1 0x42 (fixed)
  uint8_t start_2;          // Start char 2 0x4d (fixed)
  uint16_t frame_length;    // Frame length = 2x13 + 2 (data + parity)

  uint16_t pm_1_0;          // PM1.0 concentration (CF = 1, standard particles) Unit ug/m^3
  uint16_t pm_2_5;          // PM2.5 concentration (CF = 1, standard particulates) Unit ug/m^3
  uint16_t pm_10_0;         // PM10 concentration (CF = 1, standard particulate matter) Unit ug/m^3

  uint16_t pm_1_0_atmos;    // PM1.0 concentration (in the atmosphere) Unit ug/m^3
  uint16_t pm_2_5_atmos;    // PM2.5 concentration (in the atmosphere) Unit ug/m^3
  uint16_t pm_10_0_atmos;   // PM10 concentration (in the atmosphere) Unit ug/m^3

  uint16_t raw_gt_0_3;      // Particles in 0.1 liter of air > 0.3um
  uint16_t raw_gt_0_5;      // Particles in 0.1 liter of air > 0.5um
  uint16_t raw_gt_1_0;      // Particles in 0.1 liter of air > 1.0um
  uint16_t raw_gt_2_5;      // Particles in 0.1 liter of air > 2.5um
  uint16_t raw_gt_5_0;      // Particles in 0.1 liter of air > 5.0um
  uint16_t raw_gt_10_0;     // Particles in 0.1 liter of air > 10um

  uint8_t version_number;   // Version number
  uint8_t error_code;       // Error code

  uint16_t checksum;        // Sum of each byte from start_1 ... error_code
} PMS7003_STRUCT;

typedef union pms7003_data {
  unsigned char bytes[PMS7003_DATA_SIZE];
  uint16_t words[PMS7003_DATA_SIZE/2];
  PMS7003_STRUCT values;
} PMS7003_DATABUF;


class PMS7003 {
  public:
    bool debug;
    PMS7003();
    void init();
    void init(Stream *serial);
    void updateFrame();
    bool hasNewData();

    uint16_t getPM_1_0();
    uint16_t getPM_2_5();
    uint16_t getPM_10_0();
    uint16_t getPM_1_0_atmos();
    uint16_t getPM_2_5_atmos();
    uint16_t getPM_10_0_atmos();

    uint16_t getRawGreaterThan_0_3();
    uint16_t getRawGreaterThan_0_5();
    uint16_t getRawGreaterThan_1_0();
    uint16_t getRawGreaterThan_2_5();
    uint16_t getRawGreaterThan_5_0();
    uint16_t getRawGreaterThan_10_0();

    uint8_t getHWVersion();
    uint8_t getErrorCode();

  private:
    PMS7003_DATABUF sensorData;
    bool dataReady;
    bool initialized;
    Stream *serial;
    unsigned char lastByte,
                  nextByte;
    int bufferIndex;

    void dumpBytes();
    void convertSensorData();
    bool isValidChecksum();
    uint16_t uint16FromBufferData(unsigned char *buff, int loc);
};

#endif /*_PMS7003_H_*/