#ifndef _TCP_REASSEMBLY_H
#define _TCP_REASSEMBLY_H

#ifdef __cpluscplus
extern "C"
{
#endif

#include "log.h"

#include <stdint.h>

#define TCP_REASSEMBLE_DEBUG(format, ...) LOG_DEBUG("tcp_reassembly", format, ##__VA_ARGS__)
#define TCP_REASSEMBLE_ERROR(format, ...) LOG_ERROR("tcp_reassembly", format, ##__VA_ARGS__)

/*
 * If retransmission or overlap occurs, the old data packet may have been consumed by the upper-layer plug-in,
 * so the old data packet takes priority and the new data packet will be bypassed.
 */

struct tcp_reassembly_options
{
    uint8_t enable;
    uint32_t max_timeout;  // range: [1, 60000]
    uint32_t max_segments; // 0: unlimited
    uint32_t max_bytes;    // 0: unlimited
};

struct tcp_reassembly_stat
{
    uint64_t curr_segments;
    uint64_t curr_bytes;

    uint64_t insert_segments;
    uint64_t insert_bytes;

    uint64_t remove_segments;
    uint64_t remove_bytes;

    uint64_t consume_segments;
    uint64_t consume_bytes;

    uint64_t retrans_bypass_segments;
    uint64_t retrans_bypass_bytes;

    uint64_t overload_bypass_segments;
    uint64_t overload_bypass_bytes;

    uint64_t timeout_discard_segments;
    uint64_t timeout_discard_bytes;
};

struct tcp_reassembly *tcp_reassembly_new(struct tcp_reassembly_options *opts);
void tcp_reassembly_free(struct tcp_reassembly *assy);

void tcp_reassembly_init(struct tcp_reassembly *assy, uint32_t syn_seq);
void tcp_reassembly_expire(struct tcp_reassembly *assy, uint64_t now);

void tcp_reassembly_insert(struct tcp_reassembly *assy, uint32_t seq, const char *payload, uint32_t len, uint64_t now);
const char *tcp_reassembly_peek(struct tcp_reassembly *assy, uint32_t *len);
void tcp_reassembly_consume(struct tcp_reassembly *assy, uint32_t len);

struct tcp_reassembly_stat *tcp_reassembly_get_stat(struct tcp_reassembly *assy);
void tcp_reassembly_print_stat(struct tcp_reassembly *assy);

#ifdef __cpluscplus
}
#endif

#endif