#ifndef BUFFER_H_

#define BUFFER_H_

#include "common.h"

#define DEFAULT_BUFFER_CAPACITY (32)

#define MAX_BUFFER_CAPACITY (0x7fffffff)

#define MAX_BUFFER_PREALLOC (1024*1024) //adjust capacity and realloc size and strategy.

typedef struct {

atomic_t m_ref;

int32_t m_len;

int32_t m_cap;

char m_data[0];

} buffer_data_t, *buffer_data_ptr_t;

typedef struct {

buffer_data_ptr_t m_ptr;

} buffer_t;

extern buffer_t buffer_new(size_t cap, const char *init, size_t init_len);

extern bool buffer_append(buffer_t& buffer_ref, const char *data, size_t data_len);

extern bool buffer_clear(buffer_t& buffer_ref);

extern buffer_t& buffer_grab(buffer_t& buffer_ref);

extern void buffer_release(buffer_t& buffer_ref);

extern bool buffer_concat(buffer_t& dest_ref, const buffer_t& src_ref);

extern bool buffer_adjust_len(buffer_t& buffer_ref, size_t add);

extern buffer_t buffer_split(buffer_t& buffer_ref, size_t len);

#define invalid_buffer { NULL }

#define buffer_is_valid(buffer_ref) ((buffer_ref).m_ptr != NULL)

#define buffer_data_ptr(buffer_ref) ((buffer_ref).m_ptr ? (buffer_ref).m_ptr->m_data : NULL)

#define buffer_data_length(buffer_ref) ((buffer_ref).m_ptr ? (buffer_ref).m_ptr->m_len : 0)

#define buffer_write_ptr(buffer_ref) ((buffer_ref).m_ptr ? (buffer_ref).m_ptr->m_data + (buffer_ref).m_ptr->m_len : NULL)

#define buffer_write_size(buffer_ref) ((buffer_ref).m_ptr ? (buffer_ref).m_ptr->m_cap - (buffer_ref).m_ptr->m_len : 0)

#define buffer_make_invalid(buffer_ref) ((buffer_ref).m_ptr = NULL)

#endif