#ifndef GUMBO_STRING_BUFFER_H_
#define GUMBO_STRING_BUFFER_H_

#include <stdbool.h>
#include <stddef.h>

#include "nokogiri_gumbo.h"

#ifdef __cplusplus
extern "C" {
#endif

// A struct representing a mutable, growable string. This consists of a
// heap-allocated buffer that may grow (by doubling) as necessary. When
// converting to a string, this allocates a new buffer that is only as long as
// it needs to be. Note that the internal buffer here is *not* nul-terminated,
// so be sure not to use ordinary string manipulation functions on it.
typedef struct {
  // A pointer to the beginning of the string. NULL if length == 0.
  char* data;

  // The length of the string fragment, in bytes. May be zero.
  size_t length;

  // The capacity of the buffer, in bytes.
  size_t capacity;
} GumboStringBuffer;

// Initializes a new GumboStringBuffer.
void gumbo_string_buffer_init(GumboStringBuffer* output);

// Ensures that the buffer contains at least a certain amount of space. Most
// useful with snprintf and the other length-delimited string functions, which
// may want to write directly into the buffer.
void gumbo_string_buffer_reserve (
  size_t min_capacity,
  GumboStringBuffer* output
);

// Appends a single Unicode codepoint onto the end of the GumboStringBuffer.
// This is essentially a UTF-8 encoder, and may add 1-4 bytes depending on the
// value of the codepoint.
void gumbo_string_buffer_append_codepoint (
  int c,
  GumboStringBuffer* output
);

// Appends a string onto the end of the GumboStringBuffer.
void gumbo_string_buffer_append_string (
  const GumboStringPiece* str,
  GumboStringBuffer* output
);

// Converts this string buffer to const char*, alloctaing a new buffer for it.
char* gumbo_string_buffer_to_string(const GumboStringBuffer* input);

// Reinitialize this string buffer. This clears it by setting length=0. It
// does not zero out the buffer itself.
void gumbo_string_buffer_clear(GumboStringBuffer* input);

// Deallocates this GumboStringBuffer.
void gumbo_string_buffer_destroy(GumboStringBuffer* buffer);

#ifdef __cplusplus
}
#endif

#endif // GUMBO_STRING_BUFFER_H_