main.h

#include "nrf5x-compat.h"
#include "ble_stack.h"

#ifndef RANDOM_ROTATE_KEYS
#define RANDOM_ROTATE_KEYS 1
#endif

#ifndef MAX_KEYS
// Maximum number of public keys to rotate
// Can be set during compilation with make MAX_KEYS=10
#define MAX_KEYS 50
#endif

#ifndef KEY_ROTATION_INTERVAL
// Key rotation interval in seconds
#define KEY_ROTATION_INTERVAL 3600 * 3
#endif

#if NRF_SDK_VERSION < 15
    #define PRESCALER_VALUE APP_TIMER_PRESCALER
#else
    #define PRESCALER_VALUE APP_TIMER_CONFIG_RTC_FREQUENCY
#endif

#define RTC_FREQUENCY (32768 / (PRESCALER_VALUE + 1))

// Maximum number of ticks (24-bit counter)
#define MAX_RTC_TICKS 0xFFFFFF

// Maximum time before overflow, in seconds
#define MAX_TIMER_INTERVAL_SECONDS (MAX_RTC_TICKS / RTC_FREQUENCY)

// Force computation of values using macros
#define COMPUTED_RTC_FREQUENCY RTC_FREQUENCY
#define COMPUTED_MAX_TIMER_INTERVAL MAX_TIMER_INTERVAL_SECONDS

// Static assert to ensure that the key rotation interval fits within the max timer interval
_Static_assert(KEY_ROTATION_INTERVAL <= COMPUTED_MAX_TIMER_INTERVAL, "KEY_ROTATION_INTERVAL exceeds max timer interval for the configured RTC frequency.");

// Helper macro to convert values to string
#define _STRINGIFY(x) _STRINGIFY_INTERNAL(x)
#define _STRINGIFY_INTERNAL(x) #x
#pragma message("RTC_FREQUENCY: " _STRINGIFY(COMPUTED_RTC_FREQUENCY))
#pragma message("MAX_TIMER_INTERVAL_SECONDS: " _STRINGIFY(COMPUTED_MAX_TIMER_INTERVAL))