#include <string.h>
#include <pthread.h>
#include <assert.h>
#include <unistd.h>
#include <MESA/MESA_prof_load.h>
#include <net/if.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <net/if_arp.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include <net/if.h>
#include <arpa/inet.h>
#include <errno.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <netinet/ether.h>

#include "log.h"
#include "uthash.h"
#include "bfd.h"
#include "sf_status.h"
#include "utils.h"
#include "health_check.h"

#define     BUF_SIZE                4096
#define     SEND_MAX                1
#define     PACKET_SIZE             64
#define     HC_DEV_NAME_LEN         16
#define     HC_LOCAL_ADDRESS_LEN    64
#define TIMESPEC_TO_MSEC(ts) ((ts).tv_sec * 1000 + (ts).tv_nsec / 1000000)

struct session_table
{
    // handler;
    struct session_iterm *root_by_id;
    pthread_rwlock_t rwlock;
};

struct session_iterm
{
    uint64_t session_id;                // key

    struct health_check policy;         // value1: deep copy
    int is_active;                      // value2
    uuid_t sf_uuid;                     // value3
    int vsys_id;                        // value4

    UT_hash_handle hh1; /* handle for first hash table */
};

struct session_table_addr
{
    // handler;
    struct node_addr *htable;
    pthread_rwlock_t rwlock;
};

struct node_addr
{
    char address[64]; // key

    uint8_t mac[ETH_ALEN];
    int ref_cnt;                // reference 

    UT_hash_handle hh; /* handle for first hash table */
};

static uint64_t g_session_id;
static struct session_table g_handle;
static struct session_table_addr g_handle_bfd;
static struct session_table_addr g_handle_none;
static struct sf_status *g_sf_status = NULL;

int next_check_wait_ms = 300;
int enable = 1;
int icmp_cycle_time_s = 10;
char path[BFD_PATHLEN];
char hc_dev_name[HC_DEV_NAME_LEN];
char local_address[HC_LOCAL_ADDRESS_LEN];
char gateway_address[HC_LOCAL_ADDRESS_LEN];
uint8_t default_gw_mac[ETH_ALEN];

static int get_mac_by_addr(char *addr, uint8_t *buf);
static int health_check_session_foreach();

static int health_check_method_table_set_mac(struct session_table_addr *table, char *addr, uint8_t *mac)
{
    struct node_addr *tmp = NULL;

    pthread_rwlock_wrlock(&(table->rwlock));
    HASH_FIND_STR(table->htable, addr, tmp);
    if (tmp == NULL) {
        pthread_rwlock_unlock(&(table->rwlock));
        return 1;
    }

    memcpy(tmp->mac, mac, ETH_ALEN);
    pthread_rwlock_unlock(&(table->rwlock));
    return 0;
}

static int health_check_method_table_get_mac(struct session_table_addr *table, char *addr, uint8_t *out_mac)
{
    struct node_addr *tmp = NULL;

    pthread_rwlock_rdlock(&(table->rwlock));
    HASH_FIND_STR(table->htable, addr, tmp);
    if (tmp == NULL) {
        pthread_rwlock_unlock(&(table->rwlock));
        return 1;
    }

    memcpy(out_mac, tmp->mac, ETH_ALEN);
    pthread_rwlock_unlock(&(table->rwlock));
    return 0;
}

static int health_check_method_table_del(struct session_table_addr *table, char *addr)
{
    struct node_addr *tmp = NULL;

    pthread_rwlock_wrlock(&(table->rwlock));
    HASH_FIND_STR(table->htable, addr, tmp);
    if (tmp == NULL) {
        pthread_rwlock_unlock(&(table->rwlock));
        return 0;
    }

    if (--tmp->ref_cnt) {
        pthread_rwlock_unlock(&(table->rwlock));
        return 1;
    }

    HASH_DEL(table->htable, tmp);
    free(tmp);
    tmp = NULL;
    pthread_rwlock_unlock(&(table->rwlock));
    return 0;
}

static int health_check_method_table_add(struct session_table_addr *table, char *addr)
{
    struct node_addr *tmp = NULL;

    pthread_rwlock_wrlock(&(table->rwlock));
    HASH_FIND_STR(table->htable, addr, tmp);
    if (tmp) {
        tmp->ref_cnt++;
    }
    else {
        tmp = (struct node_addr *)calloc(1, sizeof(struct node_addr));
        assert(tmp);
        snprintf(tmp->address, sizeof(tmp->address), addr);
        tmp->ref_cnt++;
        HASH_ADD_STR(table->htable, address, tmp);
    }
    pthread_rwlock_unlock(&(table->rwlock));
    return 0;
}

#define CHECKSUM_CARRY(x) (x = (x >> 16) + (x & 0xffff), (~(x + (x >> 16)) & 0xffff))
static inline int checksum(uint16_t *data, int len)
{
    int sum = 0;
    int nleft = len;
    uint16_t ans = 0;
    uint16_t *w = data;

    while (nleft > 1)
    {
        sum += *w++;
        nleft -= 2;
    }

    if (nleft == 1)
    {
        *(char *)(&ans) = *(char *)w;
        sum += ans;
    }

    return sum;
}

static int send_icmp_pkt(char *addr)
{
    int sockfd;
    char packet[PACKET_SIZE] = {0};
    struct ifreq ifr;
    struct icmp *icmp = (struct icmp *)packet;
    struct sockaddr_in dest_addr;

    sockfd = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
    if (sockfd < 0)
        return 1;

    dest_addr.sin_family = AF_INET;
    dest_addr.sin_port = 0;
    if (inet_pton(AF_INET, addr, &(dest_addr.sin_addr)) <= 0) {
        close(sockfd);
        LOG_ERROR("unable to send icmp packet, address[%s] invalid!", addr);
        return 1;
    }

    memset(&ifr, 0, sizeof(ifr));
    snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s", hc_dev_name);
    if (setsockopt(sockfd, SOL_SOCKET, SO_BINDTODEVICE, (void *)&ifr, sizeof(ifr)) < 0) {
        close(sockfd);
        LOG_ERROR("unable to send icmp packet, device[%s] bind failed!", hc_dev_name);
        return 1;
    }

    icmp->icmp_type = ICMP_ECHO;
    icmp->icmp_code = 0;
    icmp->icmp_id = htons(getpid());
    icmp->icmp_seq = 0;
    icmp->icmp_cksum = 0;
    int sum = checksum((uint16_t *)icmp, PACKET_SIZE);
    icmp->icmp_cksum = CHECKSUM_CARRY(sum);

    for(int i=0; i<SEND_MAX; i++){
        sendto(sockfd, packet, PACKET_SIZE, 0, (struct sockaddr *)&dest_addr, sizeof(dest_addr));
    }

    close(sockfd);
    return 0;
}

static void *_listen_arp_table(void *arg)
{
    struct sockaddr_nl sa;
    int nl_sock;
    char buf[BUF_SIZE];
    struct in_addr ipaddr;
    uint8_t *mac = NULL;
    char str_addr[INET_ADDRSTRLEN] = {0};
    uint8_t init_mac[ETH_ALEN] = {0};

start:
    nl_sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
    if (nl_sock < 0) {
        LOG_ERROR("listen_arp_table: unable to create socket!");
        return NULL;
    }

    memset(&sa, 0, sizeof(sa));
    sa.nl_family = AF_NETLINK;
    sa.nl_groups = RTMGRP_NEIGH;

    if (bind(nl_sock, (struct sockaddr *)&sa, sizeof(sa)) != 0) {
        close(nl_sock);
        LOG_ERROR("listen_arp_table: unable to bind!");
        return NULL;
    }

    while (1) {
        int len = recv(nl_sock, buf, sizeof(buf), 0);
        if (len < 0) {
            close(nl_sock);
            goto start;
        }

        struct nlmsghdr *nh;
        for (nh = (struct nlmsghdr *)buf; NLMSG_OK(nh, len); nh = NLMSG_NEXT(nh, len)) {
            if (nh->nlmsg_type == NLMSG_DONE)
                break;

            if (nh->nlmsg_type == NLMSG_ERROR) {
                close(nl_sock);
                goto start;
            }

            struct ndmsg *nd = (struct ndmsg *)NLMSG_DATA(nh);
            struct rtattr *rth = (struct rtattr *)RTM_RTA(nd);
            int rtl = RTM_PAYLOAD(nh);

            memset(&ipaddr, 0, sizeof(ipaddr));
            mac = NULL;
            for (; RTA_OK(rth, rtl); rth = RTA_NEXT(rth, rtl)) {
                if (rth->rta_type == NDA_DST) {
                    memcpy(&ipaddr, RTA_DATA(rth), sizeof(struct in_addr));
                } else if (rth->rta_type == NDA_LLADDR) {
                    mac = (uint8_t *)RTA_DATA(rth);
                }
            }

            if (inet_ntop(AF_INET, &ipaddr, str_addr, INET_ADDRSTRLEN) != NULL) {
                if (mac == NULL) {
                    health_check_method_table_set_mac(&g_handle_bfd, str_addr, init_mac);
                    health_check_method_table_set_mac(&g_handle_none, str_addr, init_mac);
                }
                else {
                    health_check_method_table_set_mac(&g_handle_bfd, str_addr, mac);
                    health_check_method_table_set_mac(&g_handle_none, str_addr, mac);
                }
            }
        }
    }

    close(nl_sock);
    return 0;
}

static int listen_arp_table()
{    
    pthread_t pid;
    pthread_create(&pid, NULL, _listen_arp_table, NULL);
    pthread_detach(pid);
    return pid;
}

static void *_send_icmp_cycle(void *arg)
{
    struct node_addr *node = NULL;
    struct node_addr *tmp = NULL;

    while (1) {
        pthread_rwlock_rdlock(&g_handle_none.rwlock);
        HASH_ITER(hh, g_handle_none.htable, node, tmp) {
            send_icmp_pkt(node->address);
        }
        pthread_rwlock_unlock(&g_handle_none.rwlock);

        sleep(icmp_cycle_time_s);
    }
}

static int send_icmp_cycle()
{
    pthread_t pid;
    pthread_create(&pid, NULL, _send_icmp_cycle, NULL);
    pthread_detach(pid);
    return pid;
}

void health_check_session_init(const char *profile, struct kafka *kfk)
{
    char default_gw_mac_str[32] = { 0 };
    memset(&g_handle, 0, sizeof(g_handle));
    pthread_rwlock_init(&g_handle.rwlock, NULL);
    memset(&g_handle_bfd, 0, sizeof(g_handle_bfd));
    pthread_rwlock_init(&g_handle_bfd.rwlock, NULL);
    memset(&g_handle_none, 0, sizeof(g_handle_none));
    pthread_rwlock_init(&g_handle_none.rwlock, NULL);
    MESA_load_profile_int_def(profile, "bfdd", "enable", &enable, 1);
    MESA_load_profile_int_def(profile, "bfdd", "icmp_cycle_time_s", &icmp_cycle_time_s, 10);
    MESA_load_profile_string_def(profile, "bfdd", "path", path, sizeof(path), "/var/run/frr/bfdd.vty");
    MESA_load_profile_string_def(profile, "bfdd", "device", hc_dev_name, sizeof(hc_dev_name), "eth0");
    MESA_load_profile_string_def(profile, "bfdd", "local_address", local_address, sizeof(local_address), "127.0.0.1");
    MESA_load_profile_string_nodef(profile, "bfdd", "gateway", gateway_address, sizeof(gateway_address));
    MESA_load_profile_string_def(profile, "bfdd", "default_gw_mac", default_gw_mac_str, sizeof(default_gw_mac_str), "aa:aa:aa:aa:aa:aa");

    if (enable == 0)
    {
        str_to_mac(default_gw_mac_str, default_gw_mac);
        return;
    }

    g_sf_status = sf_status_create(profile, kfk);
    if (strlen(gateway_address) > 0) {
        health_check_method_table_add(&g_handle_none, gateway_address);
    }
    health_check_session_foreach();
    listen_arp_table();
    send_icmp_cycle();
}

static int health_check_session_recover_cfg(struct bfd_vtysh_client *client)
{
    int ret = 0;
    struct session_iterm *tmp = NULL;
    struct session_iterm *node = NULL;
    HASH_ITER(hh1, g_handle.root_by_id, node, tmp) {
        if (node->policy.method != HEALTH_CHECK_METHOD_BFD)
            continue;

        ret = bfd_vtysh_add_dev(client, node->policy.address, node->policy.retires, node->policy.interval_ms);
        if (ret != 0)
            return -1;
    }
    return 0;
}

static void health_check_session_init_bfd_client(struct bfd_vtysh_client *client)
{
    memset(client, 0, sizeof(*client));
    snprintf(client->path, sizeof(client->path), path);
    client->pre_config = bfd_vtysh_pre_config;
}

static void health_check_session_recover_bfd(struct bfd_vtysh_client *client)
{
    memset(client, 0, sizeof(*client));
    snprintf(client->path, sizeof(client->path), path);
    client->pre_config = bfd_vtysh_pre_config;
    client->recover_config = health_check_session_recover_cfg;
}

static int bfd_rule_add(const struct health_check *policy)
{
    int ret = 0;
    struct bfd_vtysh_client client;

    health_check_session_init_bfd_client(&client);
    bfd_vtysh_connect(&client);
    ret = bfd_vtysh_add_dev(&client, policy->address, policy->retires, policy->interval_ms);
    if (ret != 0)
        LOG_ERROR("bfd vtysh add dev address [%s] failed!", policy->address);
    bfd_vtysh_close(&client);
    return ret;
}

static int bfd_rule_del(const struct health_check *policy)
{
    int ret = 0;
    struct bfd_vtysh_client client;

    health_check_session_init_bfd_client(&client);
    bfd_vtysh_connect(&client);
    ret = bfd_vtysh_del_dev(&client, policy->address);
    if (ret != 0) {
        LOG_ERROR("bfd vtysh delete dev address [%s] failed!", policy->address);
    }
    bfd_vtysh_close(&client);
    return ret;
}

static struct session_iterm *health_check_session_get(uint64_t session_id)
{
    struct session_iterm *tmp = NULL;
    HASH_FIND(hh1, g_handle.root_by_id, &session_id, sizeof(session_id), tmp);
    return tmp;
}

static uint64_t health_check_get_session_id()
{
    struct session_iterm *tmp = NULL;
    uint64_t tmp_session_id = g_session_id;

    while(1) {
        g_session_id++;
        if (g_session_id == 0)
            g_session_id++;
        if (tmp_session_id == g_session_id)
            return 0;
        tmp = health_check_session_get(g_session_id);
        if (tmp)
            continue;
        break;
    }
    return g_session_id;
}

// return  >0 : session id
// return  0 : fail
// struct health_check *policy : need deep copy
uint64_t health_check_session_add(uuid_t *sf_uuid, int vsys_id, const struct health_check *policy)
{
    uint64_t session_id = 0;
    uint8_t mac[ETH_ALEN] = {0};
    struct session_iterm *tmp = NULL;

    if (enable == 0)
    {
        return 1;
    }

    pthread_rwlock_wrlock(&g_handle.rwlock);
    session_id = health_check_get_session_id();
    if (session_id == 0) {
        pthread_rwlock_unlock(&g_handle.rwlock);
        LOG_ERROR("health check get session id failed!");
        return 0;
    }

    tmp = (struct session_iterm *)calloc(1, sizeof(struct session_iterm));
    assert(tmp);

    tmp->vsys_id = vsys_id;
    tmp->session_id = session_id;
    uuid_copy(tmp->sf_uuid, *sf_uuid);
    memcpy(&tmp->policy, policy, sizeof(struct health_check));
    
    HASH_ADD(hh1, g_handle.root_by_id, session_id, sizeof(tmp->session_id), tmp);
    pthread_rwlock_unlock(&g_handle.rwlock);

    if (policy->method == HEALTH_CHECK_METHOD_BFD) {
        health_check_method_table_add(&g_handle_bfd, tmp->policy.address);
        bfd_rule_add(policy);
    }
    else if (policy->method == HEALTH_CHECK_METHOD_NONE) {
        health_check_method_table_add(&g_handle_none, tmp->policy.address);
        send_icmp_pkt(tmp->policy.address);
        get_mac_by_addr(tmp->policy.address, mac);
        health_check_method_table_set_mac(&g_handle_none, tmp->policy.address, mac);
    }

    char sf_uuid_str[UUID_STRING_SIZE] = {0};
    uuid_unparse(*sf_uuid, sf_uuid_str);
    LOG_DEBUG("health check session table insert: profile id [%s] session id [%lu] address [%s] success", sf_uuid_str, session_id, policy->address);
    return session_id;
}

// return  0 : success
// return -1 : key not exist
int health_check_session_del(uint64_t session_id, uuid_t *sf_uuid, int vsys_id)
{
    int ret = 0;
    struct session_iterm *tmp = NULL;

    if (enable == 0)
    {
        return 0;
    }

    pthread_rwlock_wrlock(&g_handle.rwlock);
    tmp = health_check_session_get(session_id);
    if (!tmp) {
        pthread_rwlock_unlock(&g_handle.rwlock);
        LOG_DEBUG("health check session table delete: session id [%lu] not exists", session_id);
        return -1;
    }

    if (tmp->policy.method == HEALTH_CHECK_METHOD_BFD) {
        ret = health_check_method_table_del(&g_handle_bfd, tmp->policy.address);
        if (ret != 0)
            goto end;
        bfd_rule_del(&tmp->policy);
    }
    else if (tmp->policy.method == HEALTH_CHECK_METHOD_NONE) {
        ret = health_check_method_table_del(&g_handle_none, tmp->policy.address);
    }

end:
    HASH_DELETE(hh1, g_handle.root_by_id, tmp);
    struct sf_status_key key = {0};
    key.vsys_id = vsys_id;
    uuid_copy(key.sf_uuid, *sf_uuid);
    sf_status_delete(g_sf_status, &key);
    pthread_rwlock_unlock(&g_handle.rwlock);
    free(tmp);
    tmp = NULL;

    char sf_uuid_str[UUID_STRING_SIZE] = {0};
    uuid_unparse(*sf_uuid, sf_uuid_str);
    LOG_DEBUG("health check session table delete: profile id [%s] session id [%lu] success", sf_uuid_str, session_id);
    return 0;
}

// return  1 : active
// return  0 : inactive
// return -1 : key not exist
int health_check_session_get_status(uint64_t session_id)
{
    int status = 0;
    struct session_iterm *tmp = NULL;

    if (enable == 0)
    {
        return 1;
    }

    pthread_rwlock_rdlock(&g_handle.rwlock);
    HASH_FIND(hh1, g_handle.root_by_id, &session_id, sizeof(session_id), tmp);
    if (!tmp) {
        LOG_DEBUG("health check session table get status: session id [%lu] not exists", session_id);
        pthread_rwlock_unlock(&g_handle.rwlock);
        return -1;
    }

    status = tmp->is_active;
    pthread_rwlock_unlock(&g_handle.rwlock);
    LOG_DEBUG("health check session id[%lu] get status [%d]", session_id, status);
    return status;
}

// return  0 : success
// return -1 : key not exist
int health_check_session_set_status(uint64_t session_id, int is_active)
{
    struct session_iterm *tmp = NULL;

    if (enable == 0)
    {
        return 0;
    }

    pthread_rwlock_wrlock(&g_handle.rwlock);
    HASH_FIND(hh1, g_handle.root_by_id, &session_id, sizeof(session_id), tmp);
    if (!tmp) {
        LOG_DEBUG("health check session table set status: session id [%lu] not exists", session_id);
        pthread_rwlock_unlock(&g_handle.rwlock);
        return -1;
    }

    tmp->is_active = is_active;
    pthread_rwlock_unlock(&g_handle.rwlock);
    return 0;
}

static int get_mac_by_addr(char *addr, uint8_t *buf)
{
    int sfd, ret;
    struct arpreq arp_req;
    struct sockaddr_in *sin;

    sin = (struct sockaddr_in *)&(arp_req.arp_pa);

    memset(&arp_req, 0, sizeof(arp_req));
    sin->sin_family = AF_INET;
    inet_pton(AF_INET, addr, &(sin->sin_addr));
    snprintf(arp_req.arp_dev, IFNAMSIZ, hc_dev_name);

    sfd = socket(AF_INET, SOCK_DGRAM, 0);
    if (sfd == -1)
        return -1;

    ret = ioctl(sfd, SIOCGARP, &arp_req);
    if (ret == 0)
        memcpy(buf, arp_req.arp_ha.sa_data, ETH_ALEN);

    LOG_DEBUG("IP:%s, MAC: %02x:%02x:%02x:%02x:%02x:%02x",
                addr, buf[0], buf[1], buf[2], buf[3], buf[4], buf[5]);
    close(sfd);
    return 0;
}

static void *_health_check_session_foreach(void *arg)
{
    int is_active = 0;
    int ouput_interval_ms = sf_status_get_ouput_interval_ms(g_sf_status);
    struct bfd_vtysh_client client;
    struct session_iterm *tmp = NULL;
    struct session_iterm *node = NULL;
    uint8_t mac[ETH_ALEN] = {0};
    uint8_t init_mac[ETH_ALEN] = {0};
    struct sockaddr_in addr;

    struct timespec current_time;
    struct timespec last_output_time;

    clock_gettime(CLOCK_MONOTONIC, &current_time);
    last_output_time = current_time;

    health_check_session_init_bfd_client(&client);
    bfd_vtysh_connect(&client);

    while(1) {
        pthread_rwlock_wrlock(&g_handle.rwlock);
        HASH_ITER(hh1, g_handle.root_by_id, node, tmp) {
            if (node->policy.method != HEALTH_CHECK_METHOD_BFD)
                continue;

            if (inet_pton(AF_INET, node->policy.address, &(addr.sin_addr)) > 0) {
                is_active = bfd_vtysh_get_dev_active(&client, node->policy.address);
                if (is_active == -1) {
                    bfd_vtysh_close(&client);
                    health_check_session_recover_bfd(&client);
                    bfd_vtysh_connect(&client);
                    is_active = bfd_vtysh_get_dev_active(&client, node->policy.address);
                    if (is_active == -1)
                        is_active = 0;
                }
            }
            else {
                is_active = 0;
            }

            struct sf_status_key key = {0};
            key.vsys_id = node->vsys_id;
            uuid_copy(key.sf_uuid, node->sf_uuid);
            sf_status_update(g_sf_status, &key, is_active, 0);
            if (node->is_active != is_active) {
                node->is_active = is_active;
                if (node->is_active == 1) {
                    memset(mac, 0, ETH_ALEN);
                    get_mac_by_addr(node->policy.address, mac);
                    health_check_method_table_set_mac(&g_handle_bfd, node->policy.address, mac);
                }
                else {
                    health_check_method_table_set_mac(&g_handle_bfd, node->policy.address, init_mac);
                }
            }
            if (next_check_wait_ms > node->policy.interval_ms)
                next_check_wait_ms = node->policy.interval_ms;
        }
        pthread_rwlock_unlock(&g_handle.rwlock);

        clock_gettime(CLOCK_MONOTONIC, &current_time);
        int next_output_wait_ms = ouput_interval_ms - (TIMESPEC_TO_MSEC(current_time) - TIMESPEC_TO_MSEC(last_output_time));
        if (next_output_wait_ms <= 0)
        {
            next_output_wait_ms = 0;
        }

        if (next_output_wait_ms >= next_check_wait_ms)
        {
            usleep(next_check_wait_ms * 1000);
        }
        else
        {
            usleep(next_output_wait_ms * 1000);

            clock_gettime(CLOCK_MONOTONIC, &current_time);
            sf_status_output(g_sf_status);
            last_output_time = current_time;

            usleep((next_check_wait_ms - next_output_wait_ms) * 1000);
        }
    }
    bfd_vtysh_close(&client);
    return NULL;
}

static int health_check_session_foreach()
{    
    pthread_t pid;
    pthread_create(&pid, NULL, _health_check_session_foreach, NULL);
    pthread_detach(pid);
    return pid;
}

static const char *health_check_method_str(enum health_check_method method)
{
    switch (method) {
        case HEALTH_CHECK_METHOD_NONE:
            return "HEALTH_CHECK_METHOD_NONE";
        case HEALTH_CHECK_METHOD_IN_BAND_BFD:
            return "HEALTH_CHECK_METHOD_IN_BAND_BFD";
        case HEALTH_CHECK_METHOD_BFD:
            return "HEALTH_CHECK_METHOD_BFD";
        case HEALTH_CHECK_METHOD_HTTP:
            return "HEALTH_CHECK_METHOD_HTTP";
        default:
            return NULL;
    }
}

// return  0 : success
// return -1 : key not exist
int health_check_session_get_mac(uint64_t session_id, u_char mac_buff[])
{
    const char *str_method = NULL;
    struct session_iterm *tmp = NULL;
    uint8_t mac[ETH_ALEN] = {0};
    uint8_t init_mac[ETH_ALEN] = {0};
    char sf_uuid_str[UUID_STRING_SIZE] = {0};

    if (enable == 0)
    {
        memcpy(mac_buff, default_gw_mac, ETH_ALEN);
        return 0;
    }
    pthread_rwlock_rdlock(&g_handle.rwlock);
    HASH_FIND(hh1, g_handle.root_by_id, &session_id, sizeof(session_id), tmp);
    if (!tmp) {
        LOG_DEBUG("health check session get mac: session id [%lu] not exists", session_id);
        pthread_rwlock_unlock(&g_handle.rwlock);
        return -1;
    }

    uuid_unparse(tmp->sf_uuid, sf_uuid_str);
    str_method = health_check_method_str(tmp->policy.method);
    if (tmp->policy.method == HEALTH_CHECK_METHOD_BFD && tmp->is_active == 0) {
        LOG_DEBUG("health check session id [%lu] profile id [%s] health check method [%s] active is down", session_id, sf_uuid_str, str_method);
        pthread_rwlock_unlock(&g_handle.rwlock);
        return -1;
    }

    if (tmp->policy.method == HEALTH_CHECK_METHOD_BFD) {
        health_check_method_table_get_mac(&g_handle_bfd, tmp->policy.address, mac);
    }
    else if (tmp->policy.method == HEALTH_CHECK_METHOD_NONE) {
        health_check_method_table_get_mac(&g_handle_none, tmp->policy.address, mac);
    }

    if (memcmp(mac, init_mac, ETH_ALEN) == 0) {
        if (strlen(gateway_address) == 0) {
            LOG_DEBUG("health check session id [%lu] profile id [%s] health check method [%s] get mac [null]", session_id, sf_uuid_str, str_method);
            pthread_rwlock_unlock(&g_handle.rwlock);
            return -1;
        }

        health_check_method_table_get_mac(&g_handle_none, gateway_address, mac);
        if (memcmp(mac, init_mac, ETH_ALEN) == 0) {
            LOG_DEBUG("health check session id [%lu] profile id [%s] health check method [%s] get mac [null]", session_id, sf_uuid_str, str_method);
            pthread_rwlock_unlock(&g_handle.rwlock);
            return -1;
        }
    }
    memcpy(mac_buff, mac, ETH_ALEN);
    LOG_DEBUG("health check session id [%lu] profile id [%s] health check method [%s] get mac [%02x:%02x:%02x:%02x:%02x:%02x]", session_id, sf_uuid_str, str_method, mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
    pthread_rwlock_unlock(&g_handle.rwlock);
    return 0;
}