#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <inttypes.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>

#include <net/if.h>
#include <linux/can.h>
#include <linux/can/raw.h>

#include <hexagram/capture.h>

static void usage(int argc, char **argv, const char *message, ...) {
    if (message) {
        va_list args;

        va_start(args, message);
        vfprintf(stderr, message, args);
        va_end(args);
    }

    fprintf(stderr, "usage: %s canif [file.can]\n", argv[0]);

    exit(1);
}

static int capture_replay(hexagram_capture *capture, int sock) {
    ssize_t len;
    uint32_t timestamp[2],
             usec_last = 0;
    struct can_frame frame;

    while (1) {
        if ((len = hexagram_capture_read(capture,
                                         &timestamp[0],
                                         &timestamp[1],
                                         &frame)) < 0) {
            goto error_io;
        } else if (len == 0) {
            break;
        }

        if (usec_last) {
            usleep((useconds_t)(timestamp[1] - usec_last));
        }

        if (write(sock, &frame, sizeof(struct can_frame)) < 0) {
            goto error_io;
        }

        usec_last = timestamp[1];
    }

    return 0;

error_io:
    return -1;
}

int main(int argc, char **argv) {
    struct sockaddr_can addr;
    struct ifreq ifr;
    int sock;

    hexagram_capture *capture;

    if (argc == 2) {
        if ((capture = hexagram_capture_open_fd(fileno(stdin), O_RDONLY)) == NULL) {
            goto error_capture_open;
        }
    } else if (argc == 3) {
        if ((capture = hexagram_capture_open_file(argv[2], O_RDONLY)) == NULL) {
            perror("hexagram_capture_open_file()");

            goto error_capture_open;
        }
    } else {
        usage(argc, argv, NULL);
        exit(1);
    }

    if ((sock = socket(PF_CAN, SOCK_RAW, CAN_RAW)) < 0) {
        perror("socket()");

        goto error_socket;
    }

    strcpy(ifr.ifr_name, argv[1]);

    ioctl(sock, SIOCGIFINDEX, &ifr);

    addr.can_family  = AF_CAN;
    addr.can_ifindex = ifr.ifr_ifindex;

    if (bind(sock, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
        perror("bind()");

        goto error_bind;
    }

    if (capture_replay(capture, sock) < 0) {
        perror("capture_replay()");

        goto error_capture_replay;
    }

    close(sock);

    if (argc == 3) {
        hexagram_capture_close(capture);
    }

    return 0;

error_capture_replay:
error_bind:
    close(sock);

error_socket:
    if (argc == 3) {
        hexagram_capture_close(capture);
    }

error_capture_open:
    return 1;
}