/**
 * General purpose, platform agnostic, reusable utils
 */

#ifndef COMMON_UTILS_UTILS_H
#define COMMON_UTILS_UTILS_H

#include <stdbool.h>
#include <stdint.h>

#include "base16.h"
#include "datetime.h"
#include "hexdump.h"

/** Convert a value to BCD struct */
static inline bcd_t num2bcd(uint8_t value)
{
    return (bcd_t) {.ones=value % 10, .tens=value / 10};
}

/** Convert unpacked BCD to value */
static inline uint8_t bcd2num(uint8_t tens, uint8_t ones)
{
    return tens * 10 + ones;
}

/**
 * Append to a buffer.
 *
 * In case the buffer capacity is reached, it stays unchanged (up to the terminator) and NULL is returned.
 *
 * @param buf - buffer position to append at; if NULL is given, the function immediately returns NULL.
 * @param appended - string to append
 * @param pcap - pointer to a capacity variable
 * @return the new end of the string (null byte); use as 'buf' for following appends
 */
char *append(char *buf, const char *appended, size_t *pcap);

/**
 * Test if a file descriptor is valid (e.g. when cleaning up after a failed select)
 *
 * @param fd - file descriptor number
 * @return is valid
 */
bool fd_is_valid(int fd);

/**
 * parse user-provided string as boolean
 *
 * @param str
 * @return 0 false, 1 true, -1 invalid
 */
int parse_boolean_arg(const char *str);

/** Check equality of two strings; returns bool */
#define streq(a, b) (strcmp((const char*)(a), (const char*)(b)) == 0)

/** Check prefix equality of two strings; returns bool */
#define strneq(a, b, n) (strncmp((const char*)(a), (const char*)(b), (n)) == 0)

/** Check if a string starts with a substring; returns bool */
#define strstarts(a, b) strneq((a), (b), (int)strlen((b)))

#ifndef MIN
/** Get min of two numbers */
#define MIN(a, b) ((a) > (b) ? (b) : (a))
#endif

#ifndef MAX
/** Get max of two values */
#define MAX(a, b) ((a) > (b) ? (a) : (b))
#endif

#ifndef STR
#define STR_HELPER(x) #x
/** Stringify a token */
#define STR(x) STR_HELPER(x)
#endif

#endif //COMMON_UTILS_UTILS_H