#include "Frameless.h"
#include "Utilities.h"
#include <QQuickWindow>
#include <dwmapi.h>
#include <qt_windows.h>
#include <windowsx.h>

static inline void setShadow(HWND hwnd) {
    const MARGINS shadow = {1, 0, 0, 0};
    typedef HRESULT(WINAPI * DwmExtendFrameIntoClientAreaPtr)(HWND hWnd, const MARGINS *pMarInset);
    HMODULE module = LoadLibrary(L"dwmapi.dll");
    if (module) {
        DwmExtendFrameIntoClientAreaPtr dwm_extendframe_into_client_area_;
        dwm_extendframe_into_client_area_ =
            reinterpret_cast<DwmExtendFrameIntoClientAreaPtr>(GetProcAddress(module, "DwmExtendFrameIntoClientArea"));
        if (dwm_extendframe_into_client_area_) {
            dwm_extendframe_into_client_area_(hwnd, &shadow);
        }
    }
}

static bool containsCursorToItem(QQuickItem *item) {
    auto window = item->window();
    if ((window == nullptr) || !item || !item->isVisible()) {
        return false;
    }
    auto point = window->mapFromGlobal(QCursor::pos());
    auto rect = QRectF(item->mapToItem(window->contentItem(), QPointF(0, 0)), item->size());
    if (rect.contains(point)) {
        return true;
    }
    return false;
}

Frameless::Frameless(QQuickItem *parent) : QQuickItem{parent} {
    m_isWindows11OrGreater = Utilities::instance()->isWindows11OrGreater();
}

QQuickItem *Frameless::appBar() const {
    return m_appBar;
}

void Frameless::setAppBar(QQuickItem *appBar) {
    if (m_appBar != appBar) {
        m_appBar = appBar;
        emit appBarChanged();
    }
}

QQuickItem *Frameless::maximizeButton() const {
    return m_maximizeButton;
}

void Frameless::setMaximizeButton(QQuickItem *button) {
    if (m_maximizeButton != button) {
        m_maximizeButton = button;
        emit maximizeButtonChanged();
    }
}

QQuickItem *Frameless::minimizedButton() const {
    return m_minimizedButton;
}

void Frameless::setMinimizedButton(QQuickItem *button) {
    if (m_minimizedButton != button) {
        m_minimizedButton = button;
        emit minimizedButtonChanged();
    }
}

QQuickItem *Frameless::closeButton() const {
    return m_closeButton;
}

void Frameless::setCloseButton(QQuickItem *button) {
    if (m_closeButton != button) {
        m_closeButton = button;
        emit closeButtonChanged();
    }
}

bool Frameless::fixSize() const {
    return m_fixSize;
}

void Frameless::setFixSize(bool fix) {
    if (m_fixSize != fix) {
        m_fixSize = fix;
        emit fixSizeChanged();
    }
}

bool Frameless::topmost() const {
    return m_topmost;
}

void Frameless::setTopmost(bool topmost) {
    if (m_topmost != topmost) {
        m_topmost = topmost;
        emit topmostChanged();
    }
}

bool Frameless::disabled() const {
    return m_disabled;
}

void Frameless::setDisabled(bool disabled) {
    if (m_disabled != disabled) {
        m_disabled = disabled;
        emit disabledChanged();
    }
}

void Frameless::setHitTestVisible(QQuickItem *item) {
    if (!m_hitTestList.contains(item)) {
        m_hitTestList.append(item);
    }
}

void Frameless::onDestruction() {
    QGuiApplication::instance()->removeNativeEventFilter(this);
}

void Frameless::componentComplete() {
    if (m_disabled) return;
    int w = window()->width();
    int h = window()->height();
    m_current = window()->winId();
    window()->setFlags((window()->flags()) | Qt::CustomizeWindowHint | Qt::WindowMinimizeButtonHint |
                       Qt::WindowCloseButtonHint);
    if (!m_fixSize) {
        window()->setFlag(Qt::WindowMaximizeButtonHint);
    }
    window()->installEventFilter(this);
    QGuiApplication::instance()->installNativeEventFilter(this);
    if (m_maximizeButton) {
        setHitTestVisible(m_maximizeButton);
    }
    if (m_minimizedButton) {
        setHitTestVisible(m_minimizedButton);
    }
    if (m_closeButton) {
        setHitTestVisible(m_closeButton);
    }
#ifdef Q_OS_WIN
#if (QT_VERSION == QT_VERSION_CHECK(6, 5, 3))
    qWarning() << "Qt's own frameless bug, currently only exist in 6.5.3, please use other versions";
#endif
    HWND hwnd = reinterpret_cast<HWND>(window()->winId());
    DWORD style = ::GetWindowLongPtr(hwnd, GWL_STYLE);
    if (m_fixSize) {
        ::SetWindowLongPtr(hwnd, GWL_STYLE, style | WS_THICKFRAME | WS_CAPTION);
        for (int i = 0; i <= QGuiApplication::screens().count() - 1; ++i) {
            connect(QGuiApplication::screens().at(i), &QScreen::logicalDotsPerInchChanged, this, [=] {
                SetWindowPos(hwnd, nullptr, 0, 0, 0, 0,
                             SWP_NOZORDER | SWP_NOOWNERZORDER | SWP_NOMOVE | SWP_FRAMECHANGED);
            });
        }
    } else {
        ::SetWindowLongPtr(hwnd, GWL_STYLE, style | WS_MAXIMIZEBOX | WS_THICKFRAME | WS_CAPTION);
    }
    SetWindowPos(hwnd, nullptr, 0, 0, 0, 0,
                 SWP_NOZORDER | SWP_NOOWNERZORDER | SWP_NOMOVE | SWP_NOSIZE | SWP_FRAMECHANGED);
    connect(window(), &QQuickWindow::screenChanged, this, [hwnd] {
        ::SetWindowPos(hwnd, nullptr, 0, 0, 0, 0,
                       SWP_NOMOVE | SWP_NOSIZE | SWP_NOZORDER | SWP_FRAMECHANGED | SWP_NOOWNERZORDER);
        ::RedrawWindow(hwnd, nullptr, nullptr, RDW_INVALIDATE | RDW_UPDATENOW);
    });
    if (!window()->property("_hideShadow").toBool()) {
        setShadow(hwnd);
    }
#endif
    auto appBarHeight = m_appBar->height();
    h = qRound(h + appBarHeight);
    if (m_fixSize) {
        window()->setMaximumSize(QSize(w, h));
        window()->setMinimumSize(QSize(w, h));
    } else {
        window()->setMinimumHeight(window()->minimumHeight() + appBarHeight);
        window()->setMaximumHeight(window()->maximumHeight() + appBarHeight);
    }
    window()->resize(QSize(w, h));
    connect(this, &Frameless::topmostChanged, this, [this] { setWindowTopmost(topmost()); });
    setWindowTopmost(topmost());
}

bool Frameless::eventFilter(QObject *obj, QEvent *event) {
#ifndef Q_OS_WIN
    switch (ev->type()) {
    case QEvent::MouseButtonPress:
        if (_edges != 0) {
            QMouseEvent *event = static_cast<QMouseEvent *>(ev);
            if (event->button() == Qt::LeftButton) {
                _updateCursor(_edges);
                window()->startSystemResize(Qt::Edges(_edges));
            }
        } else {
            if (_hitAppBar()) {
                qint64 clickTimer = QDateTime::currentMSecsSinceEpoch();
                qint64 offset = clickTimer - this->_clickTimer;
                this->_clickTimer = clickTimer;
                if (offset < 300) {
                    if (_isMaximized()) {
                        showNormal();
                    } else {
                        showMaximized();
                    }
                } else {
                    window()->startSystemMove();
                }
            }
        }
        break;
    case QEvent::MouseButtonRelease:
        _edges = 0;
        break;
    case QEvent::MouseMove: {
        if (_isMaximized() || _isFullScreen()) {
            break;
        }
        if (_fixSize) {
            break;
        }
        QMouseEvent *event = static_cast<QMouseEvent *>(ev);
        QPoint p =
#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
            event->pos();
#else
            event->position().toPoint();
#endif
        if (p.x() >= _margins && p.x() <= (window()->width() - _margins) && p.y() >= _margins &&
            p.y() <= (window()->height() - _margins)) {
            if (_edges != 0) {
                _edges = 0;
                _updateCursor(_edges);
            }
            break;
        }
        _edges = 0;
        if (p.x() < _margins) {
            _edges |= Qt::LeftEdge;
        }
        if (p.x() > (window()->width() - _margins)) {
            _edges |= Qt::RightEdge;
        }
        if (p.y() < _margins) {
            _edges |= Qt::TopEdge;
        }
        if (p.y() > (window()->height() - _margins)) {
            _edges |= Qt::BottomEdge;
        }
        _updateCursor(_edges);
        break;
    }
    default:
        break;
    }
#endif
    return QObject::eventFilter(obj, event);
}

bool Frameless::nativeEventFilter(const QByteArray &eventType, void *message, qintptr *result) {
#ifdef Q_OS_WIN
    if ((eventType != "windows_generic_MSG") || !message) {
        return false;
    }
    const auto msg = static_cast<const MSG *>(message);
    auto hwnd = msg->hwnd;
    if (!hwnd) {
        return false;
    }
    const quint64 wid = reinterpret_cast<qint64>(hwnd);
    if (wid != m_current) {
        return false;
    }
    const auto uMsg = msg->message;
    const auto wParam = msg->wParam;
    const auto lParam = msg->lParam;
    if (uMsg == WM_WINDOWPOSCHANGING) {
        auto *wp = reinterpret_cast<WINDOWPOS *>(lParam);
        if (wp != nullptr && (wp->flags & SWP_NOSIZE) == 0) {
            wp->flags |= SWP_NOCOPYBITS;
            *result = static_cast<qintptr>(::DefWindowProcW(hwnd, uMsg, wParam, lParam));
            return true;
        }
        return false;
    } else if (uMsg == WM_NCCALCSIZE && wParam == TRUE) {
        bool isMaximum = ::IsZoomed(hwnd);
        if (isMaximum) {
            window()->setProperty("__margins", 7);
        } else {
            window()->setProperty("__margins", 0);
        }
        setMaximizeHovered(false);
        *result = WVR_REDRAW;
        return true;
    } else if (uMsg == WM_NCHITTEST) {
        if (m_isWindows11OrGreater) {
            if (hitMaximizeButton()) {
                if (*result == HTNOWHERE) {
                    *result = HTZOOM;
                }
                setMaximizeHovered(true);
                return true;
            }
            setMaximizeHovered(false);
            setMaximizePressed(false);
        }
        *result = 0;
        POINT nativeGlobalPos{GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam)};
        POINT nativeLocalPos = nativeGlobalPos;
        ::ScreenToClient(hwnd, &nativeLocalPos);
        RECT clientRect{0, 0, 0, 0};
        ::GetClientRect(hwnd, &clientRect);
        auto clientWidth = clientRect.right - clientRect.left;
        auto clientHeight = clientRect.bottom - clientRect.top;
        bool left = nativeLocalPos.x < m_margins;
        bool right = nativeLocalPos.x > clientWidth - m_margins;
        bool top = nativeLocalPos.y < m_margins;
        bool bottom = nativeLocalPos.y > clientHeight - m_margins;
        *result = 0;
        if (!m_fixSize && !isFullScreen() && !isMaximized()) {
            if (left && top) {
                *result = HTTOPLEFT;
            } else if (left && bottom) {
                *result = HTBOTTOMLEFT;
            } else if (right && top) {
                *result = HTTOPRIGHT;
            } else if (right && bottom) {
                *result = HTBOTTOMRIGHT;
            } else if (left) {
                *result = HTLEFT;
            } else if (right) {
                *result = HTRIGHT;
            } else if (top) {
                *result = HTTOP;
            } else if (bottom) {
                *result = HTBOTTOM;
            }
        }
        if (0 != *result) {
            return true;
        }
        if (hitAppBar()) {
            *result = HTCAPTION;
            return true;
        }
        *result = HTCLIENT;
        return true;
    } else if (uMsg == WM_NCPAINT) {
        *result = FALSE;
        return false;
    } else if (uMsg == WM_NCACTIVATE) {
        *result = TRUE;
        return true;
    } else if (m_isWindows11OrGreater && (uMsg == WM_NCLBUTTONDBLCLK || uMsg == WM_NCLBUTTONDOWN)) {
        if (hitMaximizeButton()) {
            QMouseEvent event = QMouseEvent(QEvent::MouseButtonPress, QPoint(), QPoint(), Qt::LeftButton,
                                            Qt::LeftButton, Qt::NoModifier);
            QGuiApplication::sendEvent(m_maximizeButton, &event);
            setMaximizePressed(true);
            return true;
        }
    } else if (m_isWindows11OrGreater && (uMsg == WM_NCLBUTTONUP || uMsg == WM_NCRBUTTONUP)) {
        if (hitMaximizeButton()) {
            QMouseEvent event = QMouseEvent(QEvent::MouseButtonRelease, QPoint(), QPoint(), Qt::LeftButton,
                                            Qt::LeftButton, Qt::NoModifier);
            QGuiApplication::sendEvent(m_maximizeButton, &event);
            setMaximizePressed(false);
            return true;
        }
    } else if (uMsg == WM_NCRBUTTONDOWN) {
        if (wParam == HTCAPTION) {
            auto pos = window()->position();
            auto offset = window()->mapFromGlobal(QCursor::pos());
            showSystemMenu(QPoint(pos.x() + offset.x(), pos.y() + offset.y()));
        }
    } else if (uMsg == WM_KEYDOWN || uMsg == WM_SYSKEYDOWN) {
        const bool altPressed = ((wParam == VK_MENU) || (::GetKeyState(VK_MENU) < 0));
        const bool spacePressed = ((wParam == VK_SPACE) || (::GetKeyState(VK_SPACE) < 0));
        if (altPressed && spacePressed) {
            auto pos = window()->position();
            showSystemMenu(QPoint(pos.x(), qRound(pos.y() + m_appBar->height())));
        }
    } else if (uMsg == WM_SYSCOMMAND) {
        if (wParam == SC_MINIMIZE) {
            if (window()->transientParent()) {
                auto _hwnd = reinterpret_cast<HWND>(window()->transientParent()->winId());
                ::ShowWindow(_hwnd, 2);
            } else {
                auto _hwnd = reinterpret_cast<HWND>(window()->winId());
                ::ShowWindow(_hwnd, 2);
            }
            return true;
        }
        return false;
    }
    return false;
#else
    return false;
#endif
}

bool Frameless::isFullScreen() {
    return window()->visibility() == QWindow::FullScreen;
}

bool Frameless::isMaximized() {
    return window()->visibility() == QWindow::Maximized;
}

void Frameless::setMaximizeHovered(bool val) {
    if (m_maximizeButton) {
        m_maximizeButton->setProperty("hover", val);
    }
}

void Frameless::setMaximizePressed(bool val) {
    if (m_maximizeButton) {
        m_maximizeButton->setProperty("down", val);
    }
}

void Frameless::setWindowTopmost(bool topmost) {
#ifdef Q_OS_WIN
    HWND hwnd = reinterpret_cast<HWND>(window()->winId());
    if (topmost) {
        ::SetWindowPos(hwnd, HWND_TOPMOST, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE);
    } else {
        ::SetWindowPos(hwnd, HWND_NOTOPMOST, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE);
    }
#else
    window()->setFlag(Qt::WindowStaysOnTopHint, topmost);
#endif
}

bool Frameless::hitMaximizeButton() {
    if (containsCursorToItem(m_maximizeButton)) {
        return true;
    }
    return false;
}

bool Frameless::hitAppBar() {
    for (int i = 0; i <= m_hitTestList.size() - 1; ++i) {
        auto item = m_hitTestList.at(i);
        if (containsCursorToItem(item)) {
            return false;
        }
    }
    if ((m_appBar != nullptr) && containsCursorToItem(m_appBar)) {
        return true;
    }
    return false;
}

void Frameless::showSystemMenu(QPoint point) {
#ifdef Q_OS_WIN
    QScreen *screen = window()->screen();
    if (!screen) {
        screen = QGuiApplication::primaryScreen();
    }
    if (!screen) {
        return;
    }
    const QPoint origin = screen->geometry().topLeft();
    auto nativePos = QPointF(QPointF(point - origin) * window()->devicePixelRatio()).toPoint() + origin;
    HWND hwnd = reinterpret_cast<HWND>(window()->winId());
    auto hMenu = ::GetSystemMenu(hwnd, FALSE);
    if (isMaximized() || isFullScreen()) {
        ::EnableMenuItem(hMenu, SC_MOVE, MFS_DISABLED);
        ::EnableMenuItem(hMenu, SC_RESTORE, MFS_ENABLED);
    } else {
        ::EnableMenuItem(hMenu, SC_MOVE, MFS_ENABLED);
        ::EnableMenuItem(hMenu, SC_RESTORE, MFS_DISABLED);
    }
    if (!m_fixSize && !isMaximized() && !isFullScreen()) {
        ::EnableMenuItem(hMenu, SC_SIZE, MFS_ENABLED);
        ::EnableMenuItem(hMenu, SC_MAXIMIZE, MFS_ENABLED);
    } else {
        ::EnableMenuItem(hMenu, SC_SIZE, MFS_DISABLED);
        ::EnableMenuItem(hMenu, SC_MAXIMIZE, MFS_DISABLED);
    }
    const int result =
        ::TrackPopupMenu(hMenu, (TPM_RETURNCMD | (QGuiApplication::isRightToLeft() ? TPM_RIGHTALIGN : TPM_LEFTALIGN)),
                         nativePos.x(), nativePos.y(), 0, hwnd, nullptr);
    if (result) {
        ::PostMessageW(hwnd, WM_SYSCOMMAND, result, 0);
    }
#endif
}