/* Real-time thermal viewer: Win32 window showing live 160x120 frames
   with pseudo-color. Esc or close window to stop. */
#define _WIN32_WINNT 0x0601
#include <windows.h>
#include <stdio.h>
#include <libusb.h>

static libusb_device_handle *g_h;
static unsigned char g_frame[40000];
static CRITICAL_SECTION g_lock;
static volatile int g_new_frame;
static volatile int g_running;
static unsigned char g_bmp[54 + 160 * 120 * 3];
static char g_title[128];

static int sendcmd(libusb_device_handle *h, 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;
    int rc = libusb_bulk_transfer(h, 0x03, cmd, len, &xfer, 2000);
    if (rc) return rc;
    unsigned char resp[0x1000];
    rc = libusb_bulk_transfer(h, 0x82, resp, sizeof(resp), &xfer, 2000);
    return rc;
}

static void render(const unsigned char *data, unsigned mn, unsigned mx) {
    unsigned char *px = g_bmp + 54;
    for (int y = 0; y < 120; ++y) {
        for (int x = 0; x < 160; ++x) {
            int o = (y * 160 + x) * 2 + 28;
            unsigned v = (unsigned)data[o] | ((unsigned)data[o+1] << 8);
            unsigned idx = (v - mn) * 255 / (mx - mn + 1);
            if (idx > 255) idx = 255;
            unsigned char r, g, b;
            if (idx < 64)       { r = 0;   g = (unsigned char)(idx*4);   b = 255; }
            else if (idx < 128) { r = 0;   g = 255; b = (unsigned char)(255-(idx-64)*4); }
            else if (idx < 192) { r = (unsigned char)((idx-128)*4); g = 255; b = 0; }
            else                { r = 255; g = (unsigned char)(255-(idx-192)*4); b = 0; }
            int dst = (119 - y) * 160 * 3 + x * 3;
            px[dst+0] = b; px[dst+1] = g; px[dst+2] = r;
        }
    }
}

static DWORD WINAPI reader_thread(LPVOID p) {
    (void)p;
    unsigned char hdr[64];
    unsigned prev = 0xffffffff;
    int frames = 0;
    int ffc_done = 0;
    while (g_running) {
        int xfer = 0;
        if (libusb_bulk_transfer(g_h, 0x81, hdr, sizeof(hdr), &xfer, 2000) || xfer < 28) continue;
        unsigned m = (unsigned)hdr[0] | ((unsigned)hdr[1]<<8) |
                     ((unsigned)hdr[2]<<16) | ((unsigned)hdr[3]<<24);
        if (m != 0x1bb1b11b) continue;
        unsigned c = (unsigned)hdr[4] | ((unsigned)hdr[5]<<8) |
                     ((unsigned)hdr[6]<<16) | ((unsigned)hdr[7]<<24);
        if (c == prev) continue;
        prev = c;
        if (libusb_bulk_transfer(g_h, 0x81, g_frame, sizeof(g_frame), &xfer, 2000) || xfer < 38400) continue;
        frames++;
        /* switch to type=0 after the 3rd complete frame (device is streaming) */
        if (!ffc_done && frames == 3) {
            sendcmd(g_h, 0x6bb6b672, 1, 8);
            ffc_done = 1;
            Sleep(400);
            continue;
        }
        unsigned mn = 0xffff, mx = 0;
        for (int k = 0; k < 38400; k += 2) {
            unsigned v = (unsigned)g_frame[k] | ((unsigned)g_frame[k+1] << 8);
            if (v < mn) mn = v;
            if (v > mx) mx = v;
        }
        EnterCriticalSection(&g_lock);
        render(g_frame, mn, mx);
        snprintf(g_title, sizeof(g_title), "MAG160C thermal live - frame %u type=%u range [%u..%u]",
                 c, (unsigned)hdr[12], mn, mx);
        g_new_frame = 1;
        LeaveCriticalSection(&g_lock);
    }
    return 0;
}

static LRESULT CALLBACK wndproc(HWND hw, UINT msg, WPARAM wp, LPARAM lp) {
    switch (msg) {
    case WM_PAINT: {
        PAINTSTRUCT ps;
        HDC dc = BeginPaint(hw, &ps);
        HDC mem = CreateCompatibleDC(dc);
        HBITMAP bm = CreateCompatibleBitmap(dc, 160, 120);
        HGDIOBJ old = SelectObject(mem, bm);
        SetDIBitsToDevice(mem, 0, 0, 160, 120, 0, 0, 0, 120, g_bmp + 54,
                          (BITMAPINFO *)(g_bmp + 14), DIB_RGB_COLORS);
        StretchBlt(dc, 0, 0, 640, 480, mem, 0, 0, 160, 120, SRCCOPY);
        SelectObject(mem, old);
        DeleteObject(bm);
        DeleteDC(mem);
        EndPaint(hw, &ps);
        break;
    }
    case WM_ERASEBKGND:
        return 1;
    case WM_KEYDOWN:
        if (wp == VK_ESCAPE) { DestroyWindow(hw); return 0; }
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        return 0;
    }
    return DefWindowProc(hw, msg, wp, lp);
}

int WINAPI WinMain(HINSTANCE inst, HINSTANCE prev, LPSTR cmd, int show) {
    (void)prev; (void)cmd; (void)show;
    libusb_context *ctx = NULL;
    libusb_init(&ctx);
    libusb_device **list = NULL;
    ssize_t cnt = libusb_get_device_list(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);
    }
    if (!g_h) {
        MessageBoxA(NULL, "no MAG160C device found", "MAG160C", MB_ICONERROR);
        return 1;
    }
    libusb_set_configuration(g_h, 2);
    libusb_set_configuration(g_h, 1);
    libusb_claim_interface(g_h, 0);

    sendcmd(g_h, 0x6bb6b66b, 0, 4);
    sendcmd(g_h, 0x6bb6b66c, 0, 4);
    sendcmd(g_h, 0x6bb6b66f, 0, 4);
    sendcmd(g_h, 0x6bb6b672, 0, 8);
    sendcmd(g_h, 0x6bb6b672, 0, 8);
    Sleep(300);
    sendcmd(g_h, 0x6bb6b673, 0, 4);
    Sleep(500);
    /* FFC(1) is issued from the reader thread after the 3rd frame */

    WNDCLASSA wc = {0};
    wc.lpfnWndProc = wndproc;
    wc.hInstance = inst;
    wc.lpszClassName = "ThermalView";
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    RegisterClassA(&wc);
    HWND hw = CreateWindowA("ThermalView", "MAG160C thermal live",
                            WS_OVERLAPPEDWINDOW, 100, 100, 656, 520,
                            NULL, NULL, inst, NULL);

    /* BMP header */
    unsigned sz = 54 + 160*120*3;
    g_bmp[0]='B'; g_bmp[1]='M';
    g_bmp[2]=(unsigned char)sz; g_bmp[3]=(unsigned char)(sz>>8);
    g_bmp[4]=(unsigned char)(sz>>16); g_bmp[5]=(unsigned char)(sz>>24);
    g_bmp[10]=54; g_bmp[14]=40;
    g_bmp[18]=160; g_bmp[19]=0; g_bmp[22]=120; g_bmp[23]=0;
    g_bmp[26]=1; g_bmp[28]=24;

    InitializeCriticalSection(&g_lock);
    g_running = 1;
    ShowWindow(hw, SW_SHOW);

    /* single-threaded: read one frame, render, pump messages */
    int nread = 0;
    unsigned prev2 = 0xffffffff;
    int ffc2 = 0;
    for (;;) {
        MSG msg;
        while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) {
            if (msg.message == WM_QUIT) goto done;
            TranslateMessage(&msg);
            DispatchMessage(&msg);
        }
        {
            unsigned char hdr[64];
            int xfer = 0;
            if (libusb_bulk_transfer(g_h, 0x81, hdr, sizeof(hdr), &xfer, 200) && xfer < 28) continue;
            if (xfer < 28) continue;
            unsigned m = (unsigned)hdr[0] | ((unsigned)hdr[1]<<8) |
                         ((unsigned)hdr[2]<<16) | ((unsigned)hdr[3]<<24);
            if (m != 0x1bb1b11b) continue;
            unsigned c = (unsigned)hdr[4] | ((unsigned)hdr[5]<<8) |
                         ((unsigned)hdr[6]<<16) | ((unsigned)hdr[7]<<24);
            if (c == prev2) continue;
            prev2 = c;
            if (libusb_bulk_transfer(g_h, 0x81, g_frame, sizeof(g_frame), &xfer, 200) || xfer < 38400) continue;
            nread++;
            if (!ffc2 && nread == 3) {
                sendcmd(g_h, 0x6bb6b672, 1, 8);
                ffc2 = 1;
                Sleep(400);
                continue;
            }
            unsigned hist[65536] = {0};
            unsigned nz = 0;
            for (int k = 0; k < 38400; k += 2) {
                unsigned v = (unsigned)g_frame[k] | ((unsigned)g_frame[k+1] << 8);
                if (v == 0) continue;
                hist[v]++;
                nz++;
            }
            unsigned mn = 0, mx = 0;
            unsigned acc = 0;
            unsigned lo = (unsigned)(nz * 2 / 100);
            unsigned hi = (unsigned)(nz * 98 / 100);
            for (unsigned k = 0; k < 65536; ++k) {
                acc += hist[k];
                if (acc >= lo && mn == 0) mn = k;
                if (acc >= hi && mx == 0) { mx = k; break; }
            }
            if (mx <= mn + 50) { mn = 0; mx = 65535; }
            EnterCriticalSection(&g_lock);
            render(g_frame, mn, mx);
            snprintf(g_title, sizeof(g_title),
                     "MAG160C thermal live - frame %u type=%u range [%u..%u]",
                     c, (unsigned)hdr[12], mn, mx);
            LeaveCriticalSection(&g_lock);
            SetWindowTextA(hw, g_title);
            InvalidateRect(hw, NULL, FALSE);
            UpdateWindow(hw);
        }
    }
done:;
    g_running = 0;

    g_running = 0;
    Sleep(300);
    libusb_clear_halt(g_h, 0x03);
    libusb_clear_halt(g_h, 0x82);
    sendcmd(g_h, 0x6bb6b674, 0, 4);
    libusb_close(g_h);
    libusb_exit(ctx);
    return 0;
}