#include <pcap/pcap.h>
#include <pthread.h>
#include <unistd.h>

#include "stellar.h"
#include "file_scan.h"
#include "packet_io.h"
#include "packet_utils.h"
#include "packet_queue.h"
#include "packet_io_dumpfile.h"

#define MAX_PACKET_QUEUE_SIZE (4096 * 1000)

struct packet_io_dumpfile
{
    uint8_t nr_threads;
    char dumpfile_dir[256];

    pcap_t *pcap;
    struct packet_queue *queue[MAX_THREAD_NUM];
    struct packet_io_stat stat;
    uint64_t io_thread_need_exit;
    uint64_t io_thread_is_runing;
};

/******************************************************************************
 * Private API
 ******************************************************************************/

static void pcap_handle(u_char *user, const struct pcap_pkthdr *h, const u_char *bytes)
{
    struct packet_io_dumpfile *handle = (struct packet_io_dumpfile *)user;

    struct packet *pkt = packet_new(h->caplen);
    if (pkt == NULL)
    {
        PACKET_IO_LOG_ERROR("unable to alloc packet");
        return;
    }

    memcpy((char *)pkt->data_ptr, bytes, h->caplen);
    packet_parse(pkt, pkt->data_ptr, h->caplen);

    uint64_t hash = packet_get_hash(pkt, LDBC_METHOD_HASH_INT_IP_AND_EXT_IP, 0);
    struct packet_queue *queue = handle->queue[hash % handle->nr_threads];
    packet_queue_push(queue, pkt);

    if (ATOMIC_READ(&handle->io_thread_need_exit))
    {
        PACKET_IO_LOG_STATE("dumpfile io thread need exit");
        pcap_breakloop(handle->pcap);
    }
}

static int dumpfile_handle(const char *file, void *arg)
{
    struct packet_io_dumpfile *handle = (struct packet_io_dumpfile *)arg;

    PACKET_IO_LOG_STATE("dumpfile %s inprocessing", file)

    handle->pcap = pcap_open_offline(file, NULL);
    if (handle->pcap == NULL)
    {
        PACKET_IO_LOG_ERROR("unable to open pcap file: %s", file);
        return -1;
    }
    pcap_loop(handle->pcap, -1, pcap_handle, (u_char *)handle);
    pcap_close(handle->pcap);

    PACKET_IO_LOG_STATE("dumpfile %s processed", file)

    return 0;
}

static void *dumpfile_thread_cycle(void *arg)
{
    struct packet_io_dumpfile *handle = (struct packet_io_dumpfile *)arg;

    ATOMIC_SET(&handle->io_thread_is_runing, 1);
    PACKET_IO_LOG_STATE("dumpfile io thread is running");

    file_scan(handle->dumpfile_dir, dumpfile_handle, arg);

    PACKET_IO_LOG_STATE("dumpfile io thread is exiting");
    ATOMIC_SET(&handle->io_thread_is_runing, 0);

    return NULL;
}

/******************************************************************************
 * Public API
 ******************************************************************************/

struct packet_io_dumpfile *packet_io_dumpfile_new(struct packet_io_dumpfile_opts *opts)
{
    pthread_t tid;
    struct packet_io_dumpfile *handle = (struct packet_io_dumpfile *)calloc(1, sizeof(struct packet_io_dumpfile));
    if (handle == NULL)
    {
        PACKET_IO_LOG_ERROR("unable to allocate memory for packet_io_dumpfile");
        return NULL;
    }

    handle->nr_threads = opts->nr_threads;
    strncpy(handle->dumpfile_dir, opts->dumpfile_dir, sizeof(handle->dumpfile_dir));

    for (uint16_t i = 0; i < handle->nr_threads; i++)
    {
        handle->queue[i] = packet_queue_new(MAX_PACKET_QUEUE_SIZE);
        if (handle->queue[i] == NULL)
        {
            PACKET_IO_LOG_ERROR("unable to create packet queue");
            goto error_out;
        }
    }

    if (pthread_create(&tid, NULL, dumpfile_thread_cycle, (void *)handle) != 0)
    {
        PACKET_IO_LOG_ERROR("unable to create packet io thread");
        goto error_out;
    }

    return handle;

error_out:
    packet_io_dumpfile_free(handle);
    return NULL;
}

void packet_io_dumpfile_free(struct packet_io_dumpfile *handle)
{
    if (handle)
    {
        ATOMIC_SET(&handle->io_thread_need_exit, 1);

        while (ATOMIC_READ(&handle->io_thread_is_runing))
        {
            usleep(1000);
        }

        for (uint16_t i = 0; i < handle->nr_threads; i++)
        {
            packet_queue_free(handle->queue[i]);
        }
        free(handle);
        handle = NULL;
    }
}

struct packet_io_stat *packet_io_dumpfile_stat(struct packet_io_dumpfile *handle)
{
    return &handle->stat;
}

int packet_io_dumpfile_init(struct packet_io_dumpfile *handle, uint16_t thread_id)
{
    return 0;
}

int packet_io_dumpfile_recv(struct packet_io_dumpfile *handle, uint16_t thread_id, struct packet *pkts, int nr_pkts)
{
    struct packet_queue *queue = handle->queue[thread_id];
    struct packet *pkt = NULL;
    int nr_parsed = 0;

    for (int i = 0; i < nr_pkts; i++)
    {
        packet_queue_pop(queue, &pkt);
        if (pkt == NULL)
        {
            break;
        }
        else
        {
            ATOMIC_ADD(&handle->stat.rx_pkts, 1);
            ATOMIC_ADD(&handle->stat.rx_bytes, packet_get_len(pkt));

            struct packet *temp = &pkts[nr_parsed++];
            memset(temp, 0, sizeof(struct packet));
            packet_parse(temp, pkt->data_ptr, pkt->data_len);
            packet_set_io_ctx(temp, pkt);
            packet_set_type(temp, PACKET_TYPE_DATA);
            packet_set_action(temp, PACKET_ACTION_FORWARD);
        }
    }

    return nr_parsed;
}

void packet_io_dumpfile_send(struct packet_io_dumpfile *handle, uint16_t thread_id, struct packet *pkts, int nr_pkts)
{
    struct packet *pkt = NULL;
    for (int i = 0; i < nr_pkts; i++)
    {
        pkt = &pkts[i];

        if (packet_get_action(pkt) == PACKET_ACTION_DROP)
        {
            ATOMIC_ADD(&handle->stat.drop_pkts, 1);
            ATOMIC_ADD(&handle->stat.drop_bytes, packet_get_len(pkt));
        }
        else
        {
            ATOMIC_ADD(&handle->stat.tx_pkts, 1);
            ATOMIC_ADD(&handle->stat.tx_bytes, packet_get_len(pkt));
        }

        packet_free((struct packet *)packet_get_io_ctx(pkt));
        packet_free(pkt);
    }
}