// Copyright (C) 2021 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only

#include <QGuiApplication>
#include <QQmlApplicationEngine>

#include "app_environment.h"
#include "import_qml_components_plugins.h"
#include "import_qml_plugins.h"
#include <windows.h>
#include <dwmapi.h>
#include <QQuickWindow>
#include <windowsx.h>

class MyWindow : public QQuickWindow
{
    bool forceResize = false;
    Q_OBJECT
public:
    MyWindow(QQuickWindow *parent = nullptr) : QQuickWindow(parent) {
        setMaximumSize(QSize(800, 800));
        this->setFlags(Qt::FramelessWindowHint);
        this->setColor("transparent");
    }

    bool nativeEvent(const QByteArray& eventType_, void* message_, qintptr* result_) override
    {
        MSG* MSG_ = static_cast<MSG*>(message_);
        RECT rect{};
        switch (MSG_->message)
        {
        case WM_NCHITTEST:
        {
            GetWindowRect((HWND) winId(), &rect);
            long mouseY = GET_Y_LPARAM(MSG_->lParam);
            if( mouseY > rect.top && mouseY < (rect.bottom - (rect.bottom - rect.top) * 0.9))
            {
                *result_ = HTCAPTION;
                return true;
            }
            break;
        }
        case WM_NCLBUTTONDOWN:
        {
            if(MSG_->wParam == HTCAPTION)
                forceResize = true;
            break;
        }
        case WM_MOVE :
        {
            if(forceResize)
            {
                setPosition(this->x(),this->y() + this->height() * 0.2);
                resize(this->width(),this->height() + 100);
                forceResize = false;
            }
            break;
        }
        case WM_NCCALCSIZE:
        {
            if(MSG_->wParam)
                return true;
        }
        }
        return false;
    }

};
int main(int argc, char *argv[])
{
    qmlRegisterType<MyWindow>("TransparentIssueDemoApp", 1, 0, "MyWindow");
    set_qt_environment();

    QGuiApplication app(argc, argv);

    QQmlApplicationEngine engine;
    const QUrl url(u"qrc:/qt/qml/Main/main.qml"_qs);
    QObject::connect(
        &engine,
        &QQmlApplicationEngine::objectCreated,
        &app,
        [url](QObject *obj, const QUrl &objUrl) {
            if (!obj && url == objUrl)
                QCoreApplication::exit(-1);
        },
        Qt::QueuedConnection);

    engine.addImportPath(QCoreApplication::applicationDirPath() + "/qml");
    engine.addImportPath(":/");
    engine.load(url);

    MyWindow *win = qobject_cast<MyWindow*>(engine.rootObjects().first());
    HWND winH = (HWND) win->winId();

    LONG_PTR CURRENTSTYLE = GetWindowLongPtrA(winH, GWL_STYLE);
    SetWindowLongPtrA(winH, GWL_STYLE, CURRENTSTYLE | WS_THICKFRAME);

    BOOL DARK = TRUE;
    DWM_SYSTEMBACKDROP_TYPE MAINWINDOWTYPE = DWMSBT_MAINWINDOW;
    DwmSetWindowAttribute(winH, DWMWA_USE_IMMERSIVE_DARK_MODE, &DARK, sizeof(DARK));
    DwmSetWindowAttribute(winH, DWMWA_SYSTEMBACKDROP_TYPE, &MAINWINDOWTYPE, sizeof(MAINWINDOWTYPE));

    MARGINS borderlessMargin = { 0, 0, 0, 1 };
    DwmExtendFrameIntoClientArea(winH, &borderlessMargin);
    return app.exec();
}
#include "main.moc"