#ifndef UTIL_H
#define UTIL_H

#include <stdlib.h>
#include <string.h>

#include "types.h"

/**
 * Concatenate string src to the end of dst.
 */
static inline usize strlcat(char *dst, const char *src, usize dsize) {
    usize dst_len = strlen(dst);
    usize src_len = strlen(src);

    /* If destination buffer is already full or too small, can't append */
    if (dst_len >= dsize) {
        return dst_len + src_len; /* Return what length would be */
    }

    /* Calculate remaining space in destination */
    usize remaining = dsize - dst_len - 1; /* -1 for null terminator */

    if (remaining > 0) {
        /* Use strncat to append, but limit to remaining space */
        strncat(dst, src, remaining);
    }
    /* Return total length that would be created */
    return dst_len + src_len;
}

/* Copy a string safely */
static inline void strndup(char *dst, const char *src, size_t maxlen) {
    if (!dst || !src)
        return;

    size_t srclen  = strlen(src);
    size_t copylen = srclen < maxlen - 1 ? srclen : maxlen - 1;

    memcpy(dst, src, copylen);
    dst[copylen] = '\0';
}

/* Like `strstr` but find the _last_ occurrence. */
static inline char *strrstr(const char *haystack, const char *needle) {
    if (*needle == '\0') {
        return (char *)haystack + strlen(haystack);
    }
    char *result = NULL;
    char *p      = strstr(haystack, needle);

    while (p != NULL) {
        result = p;
        p      = strstr(p + 1, needle);
    }
    return result;
}

#endif