#ifndef CMARK_BUFFER_H
#define CMARK_BUFFER_H

#include <stddef.h>
#include <stdarg.h>
#include "config.h"

#ifdef __cplusplus
extern "C" {
#endif

typedef struct {
	unsigned char *ptr;
	int asize, size;
} strbuf;

extern unsigned char strbuf__initbuf[];

extern unsigned char strbuf__oom[];

#define GH_BUF_INIT { strbuf__initbuf, 0, 0 }

/**
 * Initialize a strbuf structure.
 *
 * For the cases where GH_BUF_INIT cannot be used to do static
 * initialization.
 */
void strbuf_init(strbuf *buf, int initial_size);

/**
 * Attempt to grow the buffer to hold at least `target_size` bytes.
 *
 * If the allocation fails, this will return an error.  If mark_oom is true,
 * this will mark the buffer as invalid for future operations; if false,
 * existing buffer content will be preserved, but calling code must handle
 * that buffer was not expanded.
 */
int strbuf_try_grow(strbuf *buf, int target_size, bool mark_oom);

/**
 * Grow the buffer to hold at least `target_size` bytes.
 *
 * If the allocation fails, this will return an error and the buffer will be
 * marked as invalid for future operations, invaliding contents.
 *
 * @return 0 on success or -1 on failure
 */
int strbuf_grow(strbuf *buf, int target_size);

void strbuf_free(strbuf *buf);
void strbuf_swap(strbuf *buf_a, strbuf *buf_b);

/**
 * Test if there have been any reallocation failures with this strbuf.
 *
 * Any function that writes to a strbuf can fail due to memory allocation
 * issues.  If one fails, the strbuf will be marked with an OOM error and
 * further calls to modify the buffer will fail.  Check strbuf_oom() at the
 * end of your sequence and it will be true if you ran out of memory at any
 * point with that buffer.
 *
 * @return false if no error, true if allocation error
 */
bool strbuf_oom(const strbuf *buf);

size_t strbuf_len(const strbuf *buf);

int strbuf_cmp(const strbuf *a, const strbuf *b);

void strbuf_attach(strbuf *buf, unsigned char *ptr, int asize);
unsigned char *strbuf_detach(strbuf *buf);
void strbuf_copy_cstr(char *data, int datasize, const strbuf *buf);

static inline const char *strbuf_cstr(const strbuf *buf)
{
	return (char *)buf->ptr;
}

#define strbuf_at(buf, n) ((buf)->ptr[n])

/*
 * Functions below that return int value error codes will return 0 on
 * success or -1 on failure (which generally means an allocation failed).
 * Using a strbuf where the allocation has failed with result in -1 from
 * all further calls using that buffer.  As a result, you can ignore the
 * return code of these functions and call them in a series then just call
 * strbuf_oom at the end.
 */
int strbuf_set(strbuf *buf, const unsigned char *data, int len);
int strbuf_sets(strbuf *buf, const char *string);
int strbuf_putc(strbuf *buf, int c);
int strbuf_put(strbuf *buf, const unsigned char *data, int len);
int strbuf_puts(strbuf *buf, const char *string);
int strbuf_printf(strbuf *buf, const char *format, ...)
	CMARK_ATTRIBUTE((format (printf, 2, 3)));
int strbuf_vprintf(strbuf *buf, const char *format, va_list ap);
void strbuf_clear(strbuf *buf);

int strbuf_strchr(const strbuf *buf, int c, int pos);
int strbuf_strrchr(const strbuf *buf, int c, int pos);
void strbuf_drop(strbuf *buf, int n);
void strbuf_truncate(strbuf *buf, int len);
void strbuf_rtrim(strbuf *buf);
void strbuf_trim(strbuf *buf);
void strbuf_normalize_whitespace(strbuf *s);
void strbuf_unescape(strbuf *s);

#ifdef __cplusplus
}
#endif

#endif