#include <netinet/in.h>
#include <net/if.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <assert.h>
#include <unistd.h>

#include <fcntl.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <stdint.h>
#include <arpa/inet.h>

#define PIXELS 120
#define MSGSIZE (2 + 7 * PIXELS)
#define WIDTH (640)
#define HEIGHT (360)
#define OFFSET_X 1200
#define OFFSET_Y 40
//#define DISPLAY_HOST "100.65.0.2"
#define DISPLAY_HOST "fcda:f100::d"
#define DISPLAY_PORT 5005
#define SIZE WIDTH*HEIGHT*3
#define INPUT_FILE "/tmp/video"
#define RANDOMNESS_LEN (WIDTH*HEIGHT)
#include <pthread.h>
struct mmsghdr msg[RANDOMNESS_LEN/PIXELS];
struct iovec iovec[RANDOMNESS_LEN/PIXELS];
uint8_t buf[RANDOMNESS_LEN/PIXELS][MSGSIZE];
uint64_t randomness[RANDOMNESS_LEN];
int randomness_o =0;
static unsigned long x=123456789, y=362436069, z=521288629;

unsigned long xorshf96(void) {          //period 2^96-1
    unsigned long t;
    x ^= x << 16;
    x ^= x >> 5;
    x ^= x << 1;

   t = x;
   x = y;
   y = z;
   z = t ^ x ^ y;

  return z;
}
void shuffle(uint64_t *array, size_t n)
{
    if (n > 1)
    {
        size_t i;
        for (i = 0; i < n - 1; i++)
        {
          size_t j = i + rand() / (RAND_MAX / (n - i) + 1);
          unsigned long t = array[j];
          array[j] = array[i];
          array[i] = t;
        }
    }
}
void *send_thread(void * ifname){
    int sockfd;
    struct sockaddr_in6 addr;
    sockfd = socket(AF_INET6, SOCK_DGRAM, 0);
    if (sockfd == -1) {
         perror("socket()");
     exit(EXIT_FAILURE);
    }
    struct ifreq ifr;
    memset(&ifr, 0, sizeof(ifr));
    snprintf(ifr.ifr_name, sizeof(ifr.ifr_name),(char *) ifname);
    addr.sin6_family = AF_INET6;
    addr.sin6_port = htons(DISPLAY_PORT);
    inet_pton(AF_INET6, DISPLAY_HOST, &addr.sin6_addr);

    if (connect(sockfd, (struct sockaddr *) &addr, sizeof(addr)) == -1) {
        perror("connect()");
        exit(EXIT_FAILURE);
    }
    int from = 0;
    sleep(1);
    while(1){
    int retval = sendmmsg(sockfd, &msg[from], (RANDOMNESS_LEN/PIXELS)-from, 0);
        if (retval == -1) {
            perror("sendmmsg()");
        }
        from += retval;
    if(from <= (RANDOMNESS_LEN/PIXELS)){
        from = 0;
    }
    }
}
int main(int argc, char *argv[]) {
    printf(argv[1]);
    x=rand();
    y=rand();
    z=rand();
    for(int i = 0; i < RANDOMNESS_LEN; i++) {
        randomness[i] = i;
    }
    shuffle(randomness,RANDOMNESS_LEN);
    for(int i = 0; i < RANDOMNESS_LEN/PIXELS; i++){
        iovec[i].iov_base = buf[i];
        iovec[i].iov_len = MSGSIZE;
        msg[i].msg_hdr.msg_iov = &iovec[i];
        msg[i].msg_hdr.msg_iovlen = 1;
        buf[i][0] = 0x00;
        buf[i][1] = 0x01;
    }
    int fd = open(INPUT_FILE,O_RDONLY);
    printf("fd: %d\n", fd);
    uint8_t * data = mmap(NULL, SIZE, PROT_READ , MAP_SHARED, fd, 0);
    if (data == MAP_FAILED) {
        perror("mmap");
    }
    pthread_t th1,th2,th3,th4;
    pthread_create(&th1, NULL, send_thread, argv[1]);
    while (1) {
        for(int i = 0; i < (int)(RANDOMNESS_LEN/PIXELS); i++){
            for(int j=0; j<PIXELS;j++){
                uint64_t pixel = xorshf96() % RANDOMNESS_LEN;
                uint16_t x = pixel%WIDTH;
                uint16_t y = pixel/WIDTH;
                uint16_t draw_x = OFFSET_X+x;
                uint16_t draw_y = OFFSET_Y+y;
                buf[i][2+j*7+0] = draw_x & 0xff;
                buf[i][2+j*7+1] = (draw_x >> 8) & 0xff;
                buf[i][2+j*7+2] = draw_y & 0xff;
                buf[i][2+j*7+3] = (draw_y >> 8) & 0xff;
                buf[i][2+j*7+4] = *(data+pixel*3+0) & 0xff;
                buf[i][2+j*7+5] = *(data+pixel*3+1) & 0xff;
                buf[i][2+j*7+6] = *(data+pixel*3+2) & 0xff;

            }
        }
    }
    exit(0);
}