// ###############################################  Soil moisture sensor on nRF52840 ################################################### //
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#ifndef APP_UTIL_H__
#define APP_UTIL_H__


/**@brief The interrupt priorities available to the application while the softdevice is active. */
typedef enum {
    APP_IRQ_PRIORITY_HIGH = 1,
    APP_IRQ_PRIORITY_LOW  = 3
} app_irq_priority_t;



    
/**@brief Perform rounded integer division (as opposed to truncating the result).
 *
 * @param[in]   A   Numerator.
 * @param[in]   B   Denominator.
 *
 * @return      Rounded (integer) result of dividing A by B.
 */
#define ROUNDED_DIV(A, B) (((A) + ((B) / 2)) / (B))

/**@brief Check if the integer provided is a power of two.
 *
 * @param[in]   A   Number to be tested.
 *
 * @return      true if value is power of two.
 * @return      false if value not power of two.
 */
#define IS_POWER_OF_TWO(A) ( ((A) != 0) && ((((A) - 1) & (A)) == 0) )

/**@brief Perform integer division, making sure the result is rounded up.
 *
 * @details One typical use for this is to compute the number of objects with size B is needed to
 *          hold A number of bytes.
 *
 * @param[in]   A   Numerator.
 * @param[in]   B   Denominator.
 *
 * @return      Integer result of dividing A by B, rounded up.
 */
#define CEIL_DIV(A, B)      \
    /*lint -save -e573 */   \
    ((((A) - 1) / (B)) + 1) \
    /*lint -restore */




/** @brief Converts the input voltage (in milli volts) into percentage of 3.0 Volts.
 *
 *  @details The calculation is based on a linearized version of the battery's discharge
 *           curve. 3.0V returns 100% battery level. The limit for power failure is 2.1V and
 *           is considered to be the lower boundary.
 *
 *           The discharge curve for CR2032 is non-linear. In this model it is split into
 *           4 linear sections:
 *           - Section 1: 3.0V - 2.9V = 100% - 42% (58% drop on 100 mV)
 *           - Section 2: 2.9V - 2.74V = 42% - 18% (24% drop on 160 mV)
 *           - Section 3: 2.74V - 2.44V = 18% - 6% (12% drop on 300 mV)
 *           - Section 4: 2.44V - 2.1V = 6% - 0% (6% drop on 340 mV)
 *
 *           These numbers are by no means accurate. Temperature and
 *           load in the actual application is not accounted for!
 *
 *  @param[in] mvolts The voltage in mV
 *
 *  @return    Battery level in percent.
*/
static __INLINE uint8_t battery_level_in_percent(const uint16_t mvolts)
{
    uint8_t battery_level;

    if (mvolts >= 3000)
    {
        battery_level = 100;
    }
    else if (mvolts > 2900)
    {
        battery_level = 100 - ((3000 - mvolts) * 58) / 100;
    }
    else if (mvolts > 2740)
    {
        battery_level = 42 - ((2900 - mvolts) * 24) / 160;
    }
    else if (mvolts > 2440)
    {
        battery_level = 18 - ((2740 - mvolts) * 12) / 300;
    }
    else if (mvolts > 2100)
    {
        battery_level = 6 - ((2440 - mvolts) * 6) / 340;
    }
    else
    {
        battery_level = 0;
    }

    return battery_level;
}


#endif // APP_UTIL_H__

/** @} */