/*
  This file is part of KDDockWidgets.

  SPDX-FileCopyrightText: 2019-2020 Klarälvdalens Datakonsult AB, a KDAB Group company <info@kdab.com>
  Author: Sérgio Martins <sergio.martins@kdab.com>

  SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only

  Contact KDAB at <info@kdab.com> for commercial licensing options.
*/

/**
 * @file
 * @brief A class that is QWidget when building for QtWidgets, and QObject when building for QtQuick.
 *
 * Allows to have the same code base supporting both stacks.
 *
 * @author Sérgio Martins \<sergio.martins@kdab.com\>
 */

#include "QWidgetAdapter.h"
#include "FloatingWindow_p.h"

#include <QResizeEvent>
#include <QMouseEvent>
#include <QQmlComponent>
#include <QQuickItem>
#include <QQmlEngine>

using namespace KDDockWidgets;

QWidgetAdapter::QWidgetAdapter(QQuickItem *parent, Qt::WindowFlags flags)
    : QQuickItem(parent)
    , m_windowFlags(flags)
{
    this->setParent(parent); // also set parentItem

    connect(this, &QQuickItem::widthChanged, this, [this] {
        onResize(size());
        updateGeometry();
    });

    connect(this, &QQuickItem::heightChanged, this, [this] {
        onResize(size());
        updateGeometry();
    });

    setSize(QSize(800, 800));
}

QWidgetAdapter::~QWidgetAdapter()
{
}

void QWidgetAdapter::raiseAndActivate()
{
    if (QWindow *w = windowHandle()) {
        w->raise();
        w->requestActivate();
    }
}

void QWidgetAdapter::setWindowOpacity(qreal level)
{
     if (QWindow *w = windowHandle())
         w->setOpacity(level);
}

bool QWidgetAdapter::onResize(QSize) { return false; }
void QWidgetAdapter::onLayoutRequest() {}
void QWidgetAdapter::onMousePress() {}
void QWidgetAdapter::onMouseMove(QPoint) {}
void QWidgetAdapter::onMouseRelease() {}
void QWidgetAdapter::onCloseEvent(QCloseEvent *) {}

void QWidgetAdapter::itemChange(QQuickItem::ItemChange change, const QQuickItem::ItemChangeData &data)
{
    QQuickItem::itemChange(change, data);

    // Emulate the QWidget behaviour as QQuickItem doesn't receive some QEvents.
    switch (change) {
    case QQuickItem::ItemParentHasChanged: {
        QEvent ev(QEvent::ParentChange);
        qApp->sendEvent(this, &ev); // Not calling event() directly, otherwise it would skip event filters
        Q_EMIT parentChanged();
        break;
    }
    case QQuickItem::ItemVisibleHasChanged: {
        QEvent ev(isVisible() ? QEvent::Show : QEvent::Hide);
        event(&ev);
        break;
    }
    default:
        break;
    }
}

void QWidgetAdapter::geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry)
{
    // Send a few events manually, since QQuickItem doesn't do it for us.
    QQuickItem::geometryChanged(newGeometry, oldGeometry);

    // Not calling event() directly, otherwise it would skip event filters

    if (newGeometry.size() != oldGeometry.size()) {
        QEvent ev(QEvent::Resize);
        qApp->sendEvent(this, &ev);
    }

    if (newGeometry.topLeft() != oldGeometry.topLeft()) {
        QEvent ev(QEvent::Move);
        qApp->sendEvent(this, &ev);
    }
}

void QWidgetAdapter::raise()
{
    if (QWindow *w = windowHandle())
        w->raise();
}

QSize QWidgetAdapter::minimumSize() const
{
    const QSize min = property("kddockwidgets_min_size").toSize();
    return min.expandedTo({KDDOCKWIDGETS_MIN_WIDTH, KDDOCKWIDGETS_MIN_HEIGHT});
}

QSize QWidgetAdapter::maximumSize() const
{
    const QSize max = property("kddockwidgets_max_size").toSize();
    const QSize defaultMax(KDDOCKWIDGETS_MAX_WIDTH, KDDOCKWIDGETS_MAX_HEIGHT);
    return max.isEmpty() ? defaultMax
                         : max.boundedTo(defaultMax);
}

WId QWidgetAdapter::winId() const
{
    if (QWindow *w = windowHandle())
        return w->winId();

    return -1;
}

FloatingWindow * QWidgetAdapter::floatingWindow() const
{
    if (auto fw = qobject_cast<FloatingWindow*>(window()))
        return fw;

    return nullptr;
}

QRect QWidgetAdapter::geometry() const
{
    return KDDockWidgets::Private::geometry(this);
}

QRect QWidgetAdapter::rect() const
{
    return QRectF(0, 0, width(), height()).toRect();
}

QPoint QWidgetAdapter::pos() const
{
    return geometry().topLeft();
}

void QWidgetAdapter::show()
{
    setVisible(true);
}

void QWidgetAdapter::setFixedHeight(int height)
{
    setHeight(height);
}

void QWidgetAdapter::setFixedWidth(int width)
{
    setWidth(width);
}

void QWidgetAdapter::setGeometry(QRect rect)
{
    setWidth(rect.width());
    setHeight(rect.height());
    move(rect.topLeft());
}

QRect QWidgetAdapter::frameGeometry() const
{
    if (QWindow *w = windowHandle())
        return w->frameGeometry();

    return geometry();
}

void QWidgetAdapter::grabMouse()
{
    QQuickItem::grabMouse();
}

void QWidgetAdapter::releaseMouse()
{
    QQuickItem::ungrabMouse();
}

void QWidgetAdapter::setMinimumSize(QSize sz)
{
    if (minimumSize() != sz) {
        setProperty("kddockwidgets_min_size", sz);
        updateGeometry();
    }
}

void QWidgetAdapter::setMaximumSize(QSize sz)
{
    if (minimumSize() != sz) {
        setProperty("kddockwidgets_min_size", sz);
        updateGeometry();
    }
}

void QWidgetAdapter::setMaximumSize(int w, int h)
{
    QWidgetAdapter::setMaximumSize(QSize(w, h));
}

void QWidgetAdapter::setMinimumSize(int w, int h)
{
    QWidgetAdapter::setMinimumSize(QSize(w, h));
}

void QWidgetAdapter::updateGeometry()
{
    Q_EMIT geometryUpdated();
}

void QWidgetAdapter::resize(QSize sz)
{
    setWidth(sz.width());
    setHeight(sz.height());
}

void QWidgetAdapter::resize(int w, int h)
{
    resize({w, h});
}

bool QWidgetAdapter::isMaximized() const
{
    if (QWindow *w = windowHandle())
        return w->windowStates() & Qt::WindowMaximized;

    return false;
}

bool KDDockWidgets::QWidgetAdapter::isActiveWindow() const
{
    if (QWindow *w = windowHandle())
        return w->isActive();

    return false;
}

void QWidgetAdapter::showMaximized()
{
    if (QWindow *w = windowHandle())
        w->showMaximized();
}

void QWidgetAdapter::showMinimized()
{
    if (QWindow *w = windowHandle())
        w->showMinimized();
}

void QWidgetAdapter::showNormal()
{
     if (QWindow *w = windowHandle())
         w->showNormal();
}

QWindow *QWidgetAdapter::windowHandle() const
{
    return QQuickItem::window();
}

QWidgetAdapter *QWidgetAdapter::window() const
{
    // We return the top-most QWidgetAdapter

    if (QWidgetAdapter *w = parentWidget())
        return w->window();

    return const_cast<QWidgetAdapter *>(this);
}

QWidgetAdapter *QWidgetAdapter::parentWidget() const
{
    QQuickItem *p = parentItem();
    while (p) {
        if (auto qa = qobject_cast<QWidgetAdapter*>(p))
            return qa;

        p = p->parentItem();
    }

    return nullptr;
}

QPoint QWidgetAdapter::mapToGlobal(QPoint pt) const
{
    return QQuickItem::mapToGlobal(pt).toPoint();
}

QPoint QWidgetAdapter::mapFromGlobal(QPoint pt) const
{
    return QQuickItem::mapFromGlobal(pt).toPoint();
}

QPoint QWidgetAdapter::mapTo(const QQuickItem *parent, const QPoint &pos) const
{
    if (!parent)
        return {};

    return parent->mapFromGlobal(QQuickItem::mapToGlobal(pos)).toPoint();
}

bool QWidgetAdapter::testAttribute(Qt::WidgetAttribute attr) const
{
    return m_widgetAttributes & attr;
}

void QWidgetAdapter::setAttribute(Qt::WidgetAttribute attr, bool enable)
{
    if (enable)
        m_widgetAttributes |= attr;
    else
        m_widgetAttributes &= ~attr;
}

void QWidgetAdapter::setWindowTitle(const QString &title)
{
    if (QWindow *window = windowHandle())
        window->setTitle(title);
}

void QWidgetAdapter::setWindowIcon(const QIcon &icon)
{
    if (QWindow *window = windowHandle())
        window->setIcon(icon);
}

bool QWidgetAdapter::close()
{
    QCloseEvent ev;
    onCloseEvent(&ev);

    if (ev.isAccepted()) {
        setVisible(false);
        return true;
    }

    return false;
}

QQuickItem *QWidgetAdapter::childAt(QPoint p) const
{
    return QQuickItem::childAt(p.x(), p.y());
}

void QWidgetAdapter::move(QPoint pt)
{
    move(pt.x(), pt.y());
}

void QWidgetAdapter::move(int x, int y)
{
    setX(x);
    setY(y);
    setAttribute(Qt::WA_Moved);
}

void QWidgetAdapter::setParent(QQuickItem *p)
{
    QQuickItem::setParent(p);
    QQuickItem::setParentItem(p);
}

void QWidgetAdapter::activateWindow()
{
    if (QWindow *w = windowHandle())
        w->requestActivate();
}

void QWidgetAdapter::setSizePolicy(QSizePolicy sp)
{
    m_sizePolicy = sp;
}

QSizePolicy QWidgetAdapter::sizePolicy() const
{
    return m_sizePolicy;
}

QSize QWidgetAdapter::sizeHint() const
{
    return m_sizeHint;
}

void QWidgetAdapter::setWindowFlag(int flag, bool enable)
{
    Q_UNUSED(flag);
    Q_UNUSED(enable);
}

Qt::WindowFlags QWidgetAdapter::windowFlags() const
{
    return m_windowFlags;
}

/** static */
QQuickItem *QWidgetAdapter::createItem(QQmlEngine *engine, const QString &filename)
{
    QQmlComponent component(engine, filename);
    QObject *obj = component.create();
    if (!obj) {
        qWarning() << Q_FUNC_INFO << component.errorString();
        return nullptr;
    }

    return qobject_cast<QQuickItem*>(obj);
}

void QWidgetAdapter::makeItemFillParent(QQuickItem *item)
{
    // This is equivalent to "anchors.fill: parent

    if (!item) {
        qWarning() << Q_FUNC_INFO << "Invalid item";
        return;
    }

    QQuickItem *parentItem = item->parentItem();
    if (!parentItem) {
        qWarning() << Q_FUNC_INFO << "Invalid parentItem for" << item;
        return;
    }

    QObject *anchors = item->property("anchors").value<QObject*>();
    if (!anchors) {
        qWarning() << Q_FUNC_INFO << "Invalid anchors for" << item;
        return;
    }

    anchors->setProperty("fill", QVariant::fromValue(parentItem));
}

void QWidgetAdapter::setFlag(Qt::WindowType f, bool on)
{
    if (on) {
        m_windowFlags |= f;
    } else {
        m_windowFlags &= ~f;
    }
}

Qt::FocusPolicy QWidgetAdapter::focusPolicy() const
{
    return m_focusPolicy;
}

void QWidgetAdapter::setFocusPolicy(Qt::FocusPolicy policy)
{
    m_focusPolicy = policy;
}

void QWidgetAdapter::setFocus(Qt::FocusReason reason)
{
    QQuickItem::setFocus(true, reason);
}

void QWidgetAdapter::render(QPainter *)
{
    qWarning() << Q_FUNC_INFO << "Implement me";
}

QQuickItem* KDDockWidgets::Private::widgetForWindow(QWindow *window)
{
    if (!window)
        return nullptr;

    return window->property("kddockwidgets_qwidget").value<QQuickItem*>();
}

LayoutGuestWidget::~LayoutGuestWidget() = default;