#include <stdio.h>
#include "libusb.h"
libusb_device_handle *devh;
char buf[64];
char chip[]     = "\xA1\x12\x00\x52\x11MCU ISP & WCH.CN";
char final[]    = {0xA2, 1, 0, 0};
char key[43]    = {0xA3, 40, 0};
char erase[]    = {0xA4, 1, 0, 8};
char write[64]  = {0xA5, 61, 0, 0, 0, 0, 0, 0};
char verify[64] = {0xA6, 61, 0, 0, 0, 0, 0, 0};
char info[]     = {0xA7, 2, 0, 0x1F, 0};
char xxx[]      = {0xA8, 14, 0, 7, 0, 0xFF, 0xFF, 0xFF, 0xFF, 3, 0, 0, 0, 0xFF, 0x52, 0, 0};

int usb ( unsigned char *data, int olen, int ilen ) {
    int inum, iret, onum, oret;
    if (!devh) {
        libusb_init( NULL );
        devh = libusb_open_device_with_vid_pid( NULL, 0x4348, 0x55E0 );
        libusb_claim_interface( devh, 0 );
    }
    if (olen) {
        oret = libusb_bulk_transfer( devh,    2, data, olen, &onum,  100 );
        iret = libusb_bulk_transfer( devh, 0x82, buf,  ilen, &inum, 1000 );
//      for (int i = 0; i < inum; i++) printf( "%02X ", buf[i] & 0xFF );
    }
    if (!olen || oret || iret) {
        libusb_release_interface( devh, 0 );
        libusb_close( devh );
        libusb_exit( NULL );
        exit( oret | iret );
    } else return inum;
}

int main ( int argc, char **argv ) {
    int a = 0, i, n, s;
    FILE *f;
    if ((f = fopen( argv[1], "rb" )) == NULL) exit( -1 );
//  printf( "chip %d\n",  usb( chip,  sizeof(chip)-1, 6 ));
//  printf( "info %d\n",  usb( info,  sizeof(info),  30 ));
    printf( "xxx %d\n",   usb( xxx,   sizeof(xxx),    6 ));
    printf( "info %d\n",  usb( info,  sizeof(info),  30 ));
    s = buf[22] + buf[23] + buf[24] + buf[25];
    for (i = 3; i < 43; i++) key[i] = s & 0xFF;
    printf( "key %d\n",   usb( key,   sizeof(key),    6 ));
    printf( "erase %d\n", usb( erase, sizeof(erase),  6 ));
    do {
        if (!(n = fread( buf, 1, 56, f ))) break;
        for (i = 0; i < n; i++) if (i % 8 == 7) buf[i] ^= 0x52;
        write[1] = (n + 5) & 0xFF;
        write[3] = a & 0xFF;
        write[4] = (a >> 8) & 0xFF;
        memcpy( write + 8, buf, n );
        printf( "write %d %d %d\n", a, n, usb( write, n + 8, 6 ));
        a += n;
    } while (n == 56);
/*
    a = 0;
    rewind( f );
    do {
        if (!(n = fread( buf, 1, 56, f ))) break;
        for (i = 0; i < n; i++) if (i % 8 == 7) buf[i] ^= 0x52;
        verify[1] = (n + 5) & 0xFF;
        verify[3] = a & 0xFF;
        verify[4] = (a >> 8) & 0xFF;
        memcpy( verify + 8, buf, n );
        printf( "verify %d %d %d\n", a, n, usb( verify, n + 8, 6 ));
        a += n;
    } while (n == 56);
*/
    printf( "final %d\n", usb( final, sizeof(final),  6 ));
    usb( buf, 0, 0 );
}