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#ifndef _INTMATH_H_
#define _INTMATH_H_

/**
 * \brief Compute the absolute value of the difference between two integers.
 * \param a  The first integer.
 * \param b  The second integer.
 * \return  The absolute difference.
 */
#define ABS_DIFF(a,b) ((a) < (b) ? (b) - (a) : (a) - (b))

/*------------------------------------------------------------------------------
 *         Exported functions
 *------------------------------------------------------------------------------*/

#include <stdint.h>

/**
 *  Returns the minimum value between two integers.
 *  \param a First integer to compare
 *  \param b Second integer to compare
 */
static inline int32_t min_u32(uint32_t a, uint32_t b)
{
	return a < b ? a : b;
}

/**
 *  Returns the absolute value of an integer.
 *  \param value Integer value
 */
static inline uint32_t abs_u32(int32_t value)
{
	return value > 0 ? value : -value;
}

/**
 *  Computes and returns x to the power of y.
 *  \param x Value
 *  \param y Power
 */
static inline uint32_t power_u32(uint32_t x, uint32_t y)
{
        uint32_t result = 1;
        while (y > 0) {
                result *= x;
                y--;
        }
        return result;
}

/** ISO/IEC 14882:2003(E) - 5.6 Multiplicative operators:
 * The binary / operator yields the quotient, and the binary % operator yields the remainder
 * from the division of the first expression by the second.
 * If the second operand of / or % is zero the behavior is undefined; otherwise (a/b)*b + a%b is equal to a.
 * If both operands are nonnegative then the remainder is nonnegative;
 * if not, the sign of the remainder is implementation-defined 74).
 */
static inline int fixed_mod(int a, int b)
{
	int rem = a % b;
	while (rem < 0)
		rem += b;

	return rem;
}

#endif /* _INTMATH_H_ */