main.cpp

#include "LensIt.h"
#include "WinHandles.h"

AppConfig g_config;
AppState g_app;
HWND g_hwndOverlay = NULL;
HWND g_hwndSettings = NULL;
HWND g_hwndToast = NULL;
BindingMode g_bindingMode = BindingMode::None;
float g_currentZoom = 1.0f;
float g_targetZoom = 1.0f;
float g_camX = 0.0f;
float g_camY = 0.0f;
HICON g_appIcon = NULL;
NOTIFYICONDATA g_nid = { sizeof(NOTIFYICONDATA) };

typedef BOOL(WINAPI* pfnMagSetFullscreenUseBitmapSmoothing)(BOOL);
typedef BOOL(WINAPI* pfnMagSetFullscreenWindowFilterList)(DWORD, int, HWND*);

void LoadAppIcon(HINSTANCE hInstance) {
    int cxSmall = GetSystemMetrics(SM_CXSMICON);
    int cySmall = GetSystemMetrics(SM_CYSMICON);

    g_appIcon = reinterpret_cast<HICON>(LoadImageW(
        hInstance,
        MAKEINTRESOURCE(IDI_APP_ICON),
        IMAGE_ICON,
        cxSmall,
        cySmall,
        LR_DEFAULTCOLOR
    ));

    if (!g_appIcon) {
        g_appIcon = LoadIconW(hInstance, MAKEINTRESOURCE(IDI_APP_ICON));
    }
}

void InitTray(HWND hwnd, HINSTANCE hInstance) {
    (void)hInstance;
    g_nid.hWnd = hwnd;
    g_nid.uID = 1;
    g_nid.uFlags = NIF_ICON | NIF_MESSAGE | NIF_TIP;
    g_nid.uCallbackMessage = WM_APP_TRAYMSG;
    g_nid.hIcon = g_appIcon;
    wcscpy_s(g_nid.szTip, L"LensIt");
    Shell_NotifyIcon(NIM_ADD, &g_nid);
}

static bool s_zoomTimerArmed = false;

void StartZoomTimer() {
    if (!g_hwndOverlay || s_zoomTimerArmed) return;
    s_zoomTimerArmed = SetTimer(g_hwndOverlay, 1, 14, NULL) != 0;
}

void StopZoomTimer() {
    s_zoomTimerArmed = false;
    ProcessOverlayFrame();
    if (g_hwndOverlay) KillTimer(g_hwndOverlay, 1);
}

bool RequiresZoomTimer() {
    if (g_app.isDrawingLine || g_app.isDrawingArrow || g_app.isDrawRectangle || g_app.isDrawingHighlight || g_app.isDrawingBlur) return true;
    if (fabsf(g_currentZoom - g_targetZoom) > 0.001f) return true;
    return false;
}

static LONG WINAPI UnhandledExceptionCleanup(EXCEPTION_POINTERS* pExceptionInfo) {
    (void)pExceptionInfo;
    MagSetFullscreenTransform(1.0f, 0, 0);
    return EXCEPTION_CONTINUE_SEARCH;
}

int APIENTRY WinMain(
    _In_ HINSTANCE hInstance,
    _In_opt_ HINSTANCE hPrevInstance,
    _In_ LPSTR lpCmdLine,
    _In_ int nCmdShow
) {
    (void)hPrevInstance;
    (void)lpCmdLine;
    (void)nCmdShow;

    HANDLE hSingleInstanceMutex = CreateMutexW(NULL, TRUE, L"LensIt_SingleInstance_Mutex");
    if (hSingleInstanceMutex && GetLastError() == ERROR_ALREADY_EXISTS) {
        HWND hExisting = FindWindowW(L"LensItOverlay", NULL);
        if (hExisting) {
            PostMessageW(hExisting, WM_APP_SHOWSETTINGS, 0, 0);
        }
        if (hSingleInstanceMutex) {
            CloseHandle(hSingleInstanceMutex);
        }
        return 0;
    }

    SetProcessDpiAwarenessContext(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2);
    HRESULT hrCo = CoInitializeEx(NULL, COINIT_APARTMENTTHREADED);

    GdiplusStartupInput gdiplusStartupInput;
    ULONG_PTR gdiplusToken;
    GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL);

    LoadAppIcon(hInstance);
    LoadConfig();

    if (!MagInitialize()) {
        GdiplusShutdown(gdiplusToken);
        if (SUCCEEDED(hrCo)) CoUninitialize();
        return 1;
    }

    MagShowSystemCursor(TRUE);
    SetUnhandledExceptionFilter(UnhandledExceptionCleanup);

    HMODULE hMag = GetModuleHandle(L"magnification.dll");
    if (hMag) {
        auto pSetSmoothing = (pfnMagSetFullscreenUseBitmapSmoothing)GetProcAddress(hMag, "MagSetFullscreenUseBitmapSmoothing");
        if (pSetSmoothing) pSetSmoothing(TRUE);
    }

    WNDCLASSEX wcOverlay = { sizeof(WNDCLASSEX), 0, OverlayWndProc, 0, 0, hInstance, g_appIcon, NULL, static_cast<HBRUSH>(GetStockObject(BLACK_BRUSH)), NULL, L"LensItOverlay", g_appIcon };
    RegisterClassEx(&wcOverlay);

    WNDCLASSEX wcSettings = { sizeof(WNDCLASSEX), 0, SettingsWndProc, 0, 0, hInstance, g_appIcon, LoadCursor(NULL, IDC_ARROW), NULL, NULL, L"LensItSettings", g_appIcon };
    RegisterClassEx(&wcSettings);

    WNDCLASSEX wcWelcome = { sizeof(WNDCLASSEX), 0, WelcomeWndProc, 0, 0, hInstance, g_appIcon, LoadCursor(NULL, IDC_ARROW), NULL, NULL, L"LensItWelcome", g_appIcon };
    RegisterClassEx(&wcWelcome);

    WNDCLASSEX wcToast = { sizeof(WNDCLASSEX), 0, ToastWndProc, 0, 0, hInstance, NULL, LoadCursor(NULL, IDC_ARROW), NULL, NULL, L"LensItToast", NULL };
    RegisterClassEx(&wcToast);

    InitToastWindow(hInstance);

    int vScreenX = GetSystemMetrics(SM_XVIRTUALSCREEN);
    int vScreenY = GetSystemMetrics(SM_YVIRTUALSCREEN);
    int screenW = GetSystemMetrics(SM_CXVIRTUALSCREEN);
    int screenH = GetSystemMetrics(SM_CYVIRTUALSCREEN);

    g_hwndOverlay = CreateWindowEx(
        WS_EX_TOPMOST | WS_EX_LAYERED | WS_EX_TRANSPARENT | WS_EX_TOOLWINDOW | WS_EX_NOACTIVATE,
        L"LensItOverlay", L"Overlay", WS_POPUP, vScreenX, vScreenY, screenW, screenH, NULL, NULL, hInstance, NULL
    );

    SetWindowDisplayAffinity(g_hwndOverlay, WDA_EXCLUDEFROMCAPTURE);

    if (hMag) {
        auto pSetFilter = (pfnMagSetFullscreenWindowFilterList)GetProcAddress(hMag, "MagSetFullscreenWindowFilterList");
        if (pSetFilter) {
            HWND hExclude[1] = { g_hwndOverlay };
            pSetFilter(MW_FILTERMODE_EXCLUDE, 1, hExclude);
        }
    }

    ShowWindow(g_hwndOverlay, SW_HIDE);

    RepositionOverlay();
    WM_TASKBARCREATED = RegisterWindowMessageW(L"TaskbarCreated");
    InitTray(g_hwndOverlay, hInstance);

    if (g_config.isFirstRun) {
        ShowWelcomeWindow(hInstance);
    }

    {
        UniqueHook kbdHook(SetWindowsHookEx(WH_KEYBOARD_LL, LowLevelKeyboardProc, hInstance, 0));
        UniqueHook mouseHook(SetWindowsHookEx(WH_MOUSE_LL, LowLevelMouseProc, hInstance, 0));

        MSG msg;
        while (GetMessage(&msg, NULL, 0, 0)) {
            TranslateMessage(&msg);
            DispatchMessage(&msg);
        }
    }

    Shell_NotifyIcon(NIM_DELETE, &g_nid);

    if (g_hwndToast) DestroyWindow(g_hwndToast);
    if (g_hwndSettings) DestroyWindow(g_hwndSettings);
    if (g_hwndOverlay) DestroyWindow(g_hwndOverlay);
    g_hwndSettings = NULL;
    g_hwndOverlay = NULL;
    DestroyOverlayBackbuffer();
    MagSetFullscreenTransform(1.0f, 0, 0);
    MagUninitialize();
    g_app.strokes.clear();
    g_app.currentStroke = Stroke();
    g_app.textDraft = Stroke();
    GdiplusShutdown(gdiplusToken);
    if (SUCCEEDED(hrCo)) CoUninitialize();
    if (g_appIcon) DestroyIcon(g_appIcon);
    SaveConfig();
    if (hSingleInstanceMutex) {
        ReleaseMutex(hSingleInstanceMutex);
        CloseHandle(hSingleInstanceMutex);
    }
    return 0;
}