#ifndef _ADAFRUIT_SENSOR_H
#define _ADAFRUIT_SENSOR_H

#if ARDUINO >= 100
 #include "Arduino.h"
 #include "Print.h"
#else
 #include "WProgram.h"
#endif

/* Intentionally modeled after sensors.h in the Android API:
 * https://github.com/android/platform_hardware_libhardware/blob/master/include/hardware/sensors.h */

/* Constants */
#define SENSORS_GRAVITY_EARTH             (9.80665F)              /**< Earth's gravity in m/s^2 */
#define SENSORS_GRAVITY_MOON              (1.6F)                  /**< The moon's gravity in m/s^2 */
#define SENSORS_GRAVITY_SUN               (275.0F)                /**< The sun's gravity in m/s^2 */
#define SENSORS_GRAVITY_STANDARD          (SENSORS_GRAVITY_EARTH)
#define SENSORS_MAGFIELD_EARTH_MAX        (60.0F)                 /**< Maximum magnetic field on Earth's surface */
#define SENSORS_MAGFIELD_EARTH_MIN        (30.0F)                 /**< Minimum magnetic field on Earth's surface */
#define SENSORS_PRESSURE_SEALEVELHPA      (1013.25F)              /**< Average sea level pressure is 1013.25 hPa */
#define SENSORS_DPS_TO_RADS               (0.017453293F)          /**< Degrees/s to rad/s multiplier */
#define SENSORS_GAUSS_TO_MICROTESLA       (100)                   /**< Gauss to micro-Tesla multiplier */

/** Sensor types */
typedef enum
{
  SENSOR_TYPE_ACCELEROMETER         = (1),   /**< Gravity + linear acceleration */
  SENSOR_TYPE_MAGNETIC_FIELD        = (2),
  SENSOR_TYPE_ORIENTATION           = (3),
  SENSOR_TYPE_GYROSCOPE             = (4),
  SENSOR_TYPE_LIGHT                 = (5),
  SENSOR_TYPE_PRESSURE              = (6),
  SENSOR_TYPE_PROXIMITY             = (8),
  SENSOR_TYPE_GRAVITY               = (9),
  SENSOR_TYPE_LINEAR_ACCELERATION   = (10),  /**< Acceleration not including gravity */
  SENSOR_TYPE_ROTATION_VECTOR       = (11),
  SENSOR_TYPE_RELATIVE_HUMIDITY     = (12),
  SENSOR_TYPE_AMBIENT_TEMPERATURE   = (13),
  SENSOR_TYPE_VOLTAGE               = (15),
  SENSOR_TYPE_CURRENT               = (16),
  SENSOR_TYPE_COLOR                 = (17)
} sensors_type_t;

/** struct sensors_vec_s is used to return a vector in a common format. */
typedef struct {
    union {
        float v[3];
        struct {
            float x;
            float y;
            float z;
        };
        /* Orientation sensors */
        struct {
            float azimuth;    /**< Angle between the magnetic north direction and the Y axis, around the Z axis (0<=azimuth<360).  0=North, 90=East, 180=South, 270=West */
            float pitch;      /**< Rotation around X axis (-180<=pitch<=180), with positive values when the z-axis moves toward the y-axis. */
            float roll;       /**< Rotation around Y axis (-90<=roll<=90), with positive values when the x-axis moves towards the z-axis. */
        };
    };
    int8_t status;
    uint8_t reserved[3];
} sensors_vec_t;

/** struct sensors_color_s is used to return color data in a common format. */
typedef struct {
    union {
        float c[3];
        /* RGB color space */
        struct {
            float r;       /**< Red component */
            float g;       /**< Green component */
            float b;       /**< Blue component */
        };
    };
    uint32_t rgba;         /**< 24-bit RGBA value */
} sensors_color_t;

/* Sensor event (36 bytes) */
/** struct sensor_event_s is used to provide a single sensor event in a common format. */
typedef struct
{
    int32_t version;                          /**< must be sizeof(struct sensors_event_t) */
    int32_t sensor_id;                        /**< unique sensor identifier */
    int32_t type;                             /**< sensor type */
    int32_t reserved0;                        /**< reserved */
    int32_t timestamp;                        /**< time is in milliseconds */
    union
    {
        float           data[4];
        sensors_vec_t   acceleration;         /**< acceleration values are in meter per second per second (m/s^2) */
        sensors_vec_t   magnetic;             /**< magnetic vector values are in micro-Tesla (uT) */
        sensors_vec_t   orientation;          /**< orientation values are in degrees */
        sensors_vec_t   gyro;                 /**< gyroscope values are in rad/s */
        float           temperature;          /**< temperature is in degrees centigrade (Celsius) */
        float           distance;             /**< distance in centimeters */
        float           light;                /**< light in SI lux units */
        float           pressure;             /**< pressure in hectopascal (hPa) */
        float           relative_humidity;    /**< relative humidity in percent */
        float           current;              /**< current in milliamps (mA) */
        float           voltage;              /**< voltage in volts (V) */
        sensors_color_t color;                /**< color in RGB component values */
    };
} sensors_event_t;

/* Sensor details (40 bytes) */
/** struct sensor_s is used to describe basic information about a specific sensor. */
typedef struct
{
    char     name[12];                        /**< sensor name */
    int32_t  version;                         /**< version of the hardware + driver */
    int32_t  sensor_id;                       /**< unique sensor identifier */
    int32_t  type;                            /**< this sensor's type (ex. SENSOR_TYPE_LIGHT) */
    float    max_value;                       /**< maximum value of this sensor's value in SI units */
    float    min_value;                       /**< minimum value of this sensor's value in SI units */
    float    resolution;                      /**< smallest difference between two values reported by this sensor */
    int32_t  min_delay;                       /**< min delay in microseconds between events. zero = not a constant rate */
} sensor_t;

class Adafruit_Sensor {
 public:
  // Constructor(s)
  // Adafruit_Sensor();
  void constructor();

  // These must be defined by the subclass
  virtual void getEvent(sensors_event_t*);
  virtual void getSensor(sensor_t*);

  // These helper functions are defined in Adafruit_Sensor.cpp
  size_t  serializeSensor(sensor_t);
  size_t  serializeEvent(sensors_event_t);
  size_t  logSensor(sensor_t);
  size_t  logEvent(sensors_event_t);
  int32_t average(int32_t values[], const size_t len);
  float   average(float values[], const size_t len);
};

#endif