/*
    Routines for string processing.

    *_ext_* functions are provided for foreign strings we're not in control of.
*/

#ifndef COM_STR_H
#define COM_STR_H

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

#define COM_STR_GROWABLE (1 << 0)        /* Data can grow and be reallocated. */
#define COM_STR_STACK (1 << 1)           /* Stack residing. */
#define COM_STR_SUB (1 << 2)             /* Substring of an existing one. */
#define COM_STR_NULL_TERMINATED (1 << 3) /* Whether there's NULL at last. */

/* Internal strings are assumed to have vectorizable alignment. */
/* Instead of growing strings on joining we implement ropes. */
typedef struct com_str {
  struct com_str *next;
  /* Actual size is +1, to fit NULL terminator. */
  uint32_t len;
  uint32_t flags;
  char data[] __attribute__((aligned(COM_DEF_ALIGNMENT)));

} com_str;

/* NOTE: Have to be moved to static or global memory. */
#define com_str_lit(p_l) {NULL, sizeof(p_l) - 1, COM_STR_NULL_TERMINATED, (p_l)}

static inline uint32_t com_str_ext_len(char const *s) {
  char const *p = s;
  for (; *p != 0; ++p) {
  }
  return p - s;
}

/* Returns index of a char or -1 if it's not found. */
static inline int32_t com_str_ext_find_char(char const *s, char ch) {
  for (char const *p = s; *p != 0; ++p)
    if (*p == ch)
      return p - s;
  return -1;
}

/* Returns true if string 'a' is prefixed by 'b'. */
static inline bool com_str_ext_prefixed(char const *__restrict a,
                                        struct com_str prefix) {
  uint32_t n = prefix.len;
  char *b = prefix.data;
  while (n && *a && (*a == *b)) {
    ++a;
    ++b;
    --n;
  }
  return n == 0;
}

#endif