/* Verify the exact frame layout: print lengths and markers of the two
 * bulk reads (header read + data read), and the tail bytes. */
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <windows.h>
#include <libusb.h>

static libusb_context *g_ctx;
static libusb_device_handle *g_h;

static int sendcmd(unsigned magic, unsigned param, int len) {
    unsigned char cmd[8] = {0};
    cmd[0] = (unsigned char)(magic);
    cmd[1] = (unsigned char)(magic >> 8);
    cmd[2] = (unsigned char)(magic >> 16);
    cmd[3] = (unsigned char)(magic >> 24);
    if (len >= 8) {
        cmd[4] = (unsigned char)(param);
        cmd[5] = (unsigned char)(param >> 8);
        cmd[6] = (unsigned char)(param >> 16);
        cmd[7] = (unsigned char)(param >> 24);
    }
    int xfer = 0;
    if (libusb_bulk_transfer(g_h, 0x03, cmd, len, &xfer, 2000)) return -1;
    unsigned char resp[0x1000];
    if (libusb_bulk_transfer(g_h, 0x82, resp, sizeof(resp), &xfer, 2000)) return -1;
    return 0;
}

int main(void) {
    if (libusb_init(&g_ctx)) return 1;
    libusb_device **list = NULL;
    ssize_t cnt = libusb_get_device_list(g_ctx, &list);
    for (ssize_t i = 0; i < cnt && !g_h; ++i) {
        struct libusb_device_descriptor d;
        libusb_get_device_descriptor(list[i], &d);
        if (d.idVendor == 0x833c) libusb_open(list[i], &g_h);
    }
    libusb_free_device_list(list, 1);
    if (!g_h) { printf("no device\n"); return 1; }
    libusb_set_configuration(g_h, 2);
    libusb_set_configuration(g_h, 1);
    libusb_claim_interface(g_h, 0);
    sendcmd(0x6bb6b66b, 0, 4);
    sendcmd(0x6bb6b66c, 0, 4);
    sendcmd(0x6bb6b66f, 0, 4);
    sendcmd(0x6bb6b672, 0, 8);
    Sleep(100);
    sendcmd(0x6bb6b672, 0, 8);
    Sleep(300);
    sendcmd(0x6bb6b673, 0, 4);
    Sleep(700);

    unsigned char hdr[64];
    unsigned char buf[40000];
    unsigned prev = 0xffffffff;
    int frames = 0;
    int ffc_done = 0;

    while (frames < 6) {
        int xfer = 0;
        int rc = libusb_bulk_transfer(g_h, 0x81, hdr, sizeof(hdr), &xfer, 500);
        if (rc || xfer < 28) { printf("hdr rc=%d xfer=%d\n", rc, xfer); Sleep(10); continue; }
        printf("HDR read: xfer=%d marker=%02x %02x %02x %02x\n",
               xfer, hdr[0], hdr[1], hdr[2], hdr[3]);
        unsigned c = (unsigned)hdr[4] | ((unsigned)hdr[5] << 8) |
                     ((unsigned)hdr[6] << 16) | ((unsigned)hdr[7] << 24);
        if (c == prev) { printf("  dup frame %u\n", c); continue; }
        prev = c;
        xfer = 0;
        rc = libusb_bulk_transfer(g_h, 0x81, buf, sizeof(buf), &xfer, 500);
        printf("DATA read: rc=%d xfer=%d\n", rc, xfer);
        if (xfer >= 8) {
            printf("  first8: %02x %02x %02x %02x %02x %02x %02x %02x\n",
                   buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6], buf[7]);
            printf("  last8 : %02x %02x %02x %02x %02x %02x %02x %02x\n",
                   buf[xfer-8], buf[xfer-7], buf[xfer-6], buf[xfer-5],
                   buf[xfer-4], buf[xfer-3], buf[xfer-2], buf[xfer-1]);
        }
        frames++;
        if (!ffc_done && frames == 2) { sendcmd(0x6bb6b672, 1, 8); ffc_done = 1; Sleep(200); }
        /* also print type */
        printf("  type=%u (from hdr[12])\n", (unsigned)hdr[12]);
        /* search for 1b b1 b1 1c in the data buffer */
        int found = -1;
        for (int i = 0; i + 4 <= xfer; ++i)
            if (buf[i]==0x1b && buf[i+1]==0xb1 && buf[i+2]==0xb1 && buf[i+3]==0x1c) { found = i; break; }
        printf("  trailer 1bb1b11c found at offset %d\n", found);
    }
    Sleep(300);
    libusb_clear_halt(g_h, 0x03);
    libusb_clear_halt(g_h, 0x82);
    sendcmd(0x6bb6b674, 0, 4);
    libusb_close(g_h);
    libusb_exit(g_ctx);
    return 0;
}