/* fixed.h - Q16.16 Fixed-Point Math Library in C89 */

#ifndef FIXED_H
#define FIXED_H

#include <stdint.h>

/* Q16.16 fixed-point type */
typedef int32_t fixed_t;

/* Constants */
#define FIXED_ONE       0x00010000L    /* 1.0 in Q16.16 */
#define FIXED_ZERO      0x00000000L    /* 0.0 in Q16.16 */
#define FIXED_HALF      0x00008000L    /* 0.5 in Q16.16 */
#define FIXED_PI        0x0003243FL    /* π ≈ 3.14159 */
#define FIXED_E         0x0002B7E1L    /* e ≈ 2.71828 */
#define FIXED_MAX       0x7FFFFFFFL    /* Maximum positive value */
#define FIXED_MIN       0x80000000L    /* Minimum negative value */

/* Conversion functions */
fixed_t int_to_fixed(int32_t i);
int32_t fixed_to_int(fixed_t f);
fixed_t float_to_fixed(float f);
float fixed_to_float(fixed_t f);

/* Basic arithmetic operations */
fixed_t fixed_add(fixed_t a, fixed_t b);
fixed_t fixed_sub(fixed_t a, fixed_t b);
fixed_t fixed_mul(fixed_t a, fixed_t b);
fixed_t fixed_div(fixed_t a, fixed_t b);

/* Comparison functions */
int fixed_eq(fixed_t a, fixed_t b);
int fixed_ne(fixed_t a, fixed_t b);
int fixed_lt(fixed_t a, fixed_t b);
int fixed_le(fixed_t a, fixed_t b);
int fixed_gt(fixed_t a, fixed_t b);
int fixed_ge(fixed_t a, fixed_t b);

/* Unary operations */
fixed_t fixed_neg(fixed_t f);
fixed_t fixed_abs(fixed_t f);

/* Advanced math functions */
fixed_t fixed_sqrt(fixed_t f);
fixed_t fixed_sin(fixed_t f);  /* f in radians */
fixed_t fixed_cos(fixed_t f);  /* f in radians */
fixed_t fixed_tan(fixed_t f);  /* f in radians */

/* Utility functions */
fixed_t fixed_min(fixed_t a, fixed_t b);
fixed_t fixed_max(fixed_t a, fixed_t b);
fixed_t fixed_clamp(fixed_t f, fixed_t min, fixed_t max);

#endif /* FIXED_H */