/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the Qt Designer of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:GPL-EXCEPT$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3 as published by the Free Software
** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "qdesigner_stackedbox_p.h"
#include "qdesigner_command_p.h"
#include "qdesigner_propertycommand_p.h"
#include "orderdialog_p.h"
#include "promotiontaskmenu_p.h"
#include "widgetfactory_p.h"

#include <QtDesigner/QDesignerFormWindowInterface>

#include <QtWidgets/QToolButton>
#include <QtWidgets/QAction>
#include <QtGui/qevent.h>
#include <QtWidgets/QMenu>
#include <QtWidgets/QStackedWidget>
#include <QtCore/QDebug>

QT_BEGIN_NAMESPACE

static QToolButton *createToolButton(QWidget *parent, Qt::ArrowType at, const QString &name) {
    QToolButton *rc =  new QToolButton();
    rc->setAttribute(Qt::WA_NoChildEventsForParent, true);
    rc->setParent(parent);
    rc->setObjectName(name);
    rc->setArrowType(at);
    rc->setAutoRaise(true);
    rc->setSizePolicy(QSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed));
    rc->setFixedSize(QSize(15, 15));
    return rc;
}

// ---------------  QStackedWidgetPreviewEventFilter
QStackedWidgetPreviewEventFilter::QStackedWidgetPreviewEventFilter(QStackedWidget *parent) :
    QObject(parent),
    m_buttonToolTipEnabled(false), // Not on preview
    m_stackedWidget(parent),
    m_prev(createToolButton(m_stackedWidget, Qt::LeftArrow,  QStringLiteral("__qt__passive_prev"))),
    m_next(createToolButton(m_stackedWidget, Qt::RightArrow, QStringLiteral("__qt__passive_next")))
{
    connect(m_prev, &QAbstractButton::clicked, this, &QStackedWidgetPreviewEventFilter::prevPage);
    connect(m_next, &QAbstractButton::clicked, this, &QStackedWidgetPreviewEventFilter::nextPage);

    updateButtons();
    m_stackedWidget->installEventFilter(this);
    m_prev->installEventFilter(this);
    m_next->installEventFilter(this);
}

void QStackedWidgetPreviewEventFilter::install(QStackedWidget *stackedWidget)
{
    new QStackedWidgetPreviewEventFilter(stackedWidget);
}

void QStackedWidgetPreviewEventFilter::updateButtons()
{
    m_prev->move(m_stackedWidget->width() - 31, 1);
    m_prev->show();
    m_prev->raise();

    m_next->move(m_stackedWidget->width() - 16, 1);
    m_next->show();
    m_next->raise();
}

void QStackedWidgetPreviewEventFilter::prevPage()
{
    if (QDesignerFormWindowInterface *fw = QDesignerFormWindowInterface::findFormWindow(stackedWidget())) {
        fw->clearSelection();
        fw->selectWidget(stackedWidget(), true);
    }
    const int count = m_stackedWidget->count();
    if (count > 1) {
        int newIndex = m_stackedWidget->currentIndex() - 1;
        if (newIndex < 0)
            newIndex = count - 1;
        gotoPage(newIndex);
    }
}

void QStackedWidgetPreviewEventFilter::nextPage()
{
    if (QDesignerFormWindowInterface *fw = QDesignerFormWindowInterface::findFormWindow(stackedWidget())) {
        fw->clearSelection();
        fw->selectWidget(stackedWidget(), true);
    }
    const int count = m_stackedWidget->count();
    if (count > 1)
        gotoPage((m_stackedWidget->currentIndex() + 1) % count);
}

bool QStackedWidgetPreviewEventFilter::eventFilter(QObject *watched, QEvent *event)
{
    if (watched->isWidgetType()) {
        if (watched == m_stackedWidget) {
            switch (event->type()) {
            case QEvent::LayoutRequest:
                updateButtons();
                break;
            case QEvent::ChildAdded:
            case QEvent::ChildRemoved:
            case QEvent::Resize:
            case QEvent::Show:
                updateButtons();
                break;
            default:
                break;
            }
        }
        if (m_buttonToolTipEnabled && (watched == m_next || watched == m_prev)) {
            switch (event->type()) {
            case QEvent::ToolTip:
                updateButtonToolTip(watched); // Tooltip includes page number, so, refresh on demand
                break;
            default:
                break;
            }
        }
    }
    return QObject::eventFilter(watched, event);
}

void QStackedWidgetPreviewEventFilter::gotoPage(int page)
{
    m_stackedWidget->setCurrentIndex(page);
    updateButtons();
}

static inline QString stackedClassName(QStackedWidget *w)
{
    if (const QDesignerFormWindowInterface *fw = QDesignerFormWindowInterface::findFormWindow(w))
        return qdesigner_internal::WidgetFactory::classNameOf(fw->core(), w);
    return QStringLiteral("Stacked widget");
}

void QStackedWidgetPreviewEventFilter::updateButtonToolTip(QObject *o)
{
    if (o == m_prev) {
        const QString msg = tr("Go to previous page of %1 '%2' (%3/%4).").arg(stackedClassName(m_stackedWidget)).arg(m_stackedWidget->objectName()).arg(m_stackedWidget->currentIndex() + 1).arg(m_stackedWidget->count());
        m_prev->setToolTip(msg);
    } else {
        if (o == m_next) {
            const QString msg = tr("Go to next page of %1 '%2' (%3/%4).").arg(stackedClassName(m_stackedWidget)).arg(m_stackedWidget->objectName()).arg(m_stackedWidget->currentIndex() + 1).arg(m_stackedWidget->count());
            m_next->setToolTip(msg);
        }
    }
}

// ---------------  QStackedWidgetEventFilter
QStackedWidgetEventFilter::QStackedWidgetEventFilter(QStackedWidget *parent) :
    QStackedWidgetPreviewEventFilter(parent),
    m_actionPreviousPage(new QAction(tr("Previous Page"), this)),
    m_actionNextPage(new QAction(tr("Next Page"), this)),
    m_actionDeletePage(new QAction(tr("Delete"), this)),
    m_actionInsertPage(new QAction(tr("Before Current Page"), this)),
    m_actionInsertPageAfter(new QAction(tr("After Current Page"), this)),
    m_actionChangePageOrder(new QAction(tr("Change Page Order..."), this)),
    m_pagePromotionTaskMenu(new qdesigner_internal::PromotionTaskMenu(0, qdesigner_internal::PromotionTaskMenu::ModeSingleWidget, this))
{
    setButtonToolTipEnabled(true);
    connect(m_actionPreviousPage, &QAction::triggered, this, &QStackedWidgetEventFilter::prevPage);
    connect(m_actionNextPage, &QAction::triggered, this, &QStackedWidgetEventFilter::nextPage);
    connect(m_actionDeletePage, &QAction::triggered, this, &QStackedWidgetEventFilter::removeCurrentPage);
    connect(m_actionInsertPage, &QAction::triggered, this, &QStackedWidgetEventFilter::addPage);
    connect(m_actionInsertPageAfter, &QAction::triggered, this, &QStackedWidgetEventFilter::addPageAfter);
    connect(m_actionChangePageOrder, &QAction::triggered, this, &QStackedWidgetEventFilter::changeOrder);
}

void QStackedWidgetEventFilter::install(QStackedWidget *stackedWidget)
{
    new QStackedWidgetEventFilter(stackedWidget);
}

QStackedWidgetEventFilter *QStackedWidgetEventFilter::eventFilterOf(const QStackedWidget *stackedWidget)
{
    // Look for 1st order children only..otherwise, we might get filters of nested widgets
    const QObjectList children = stackedWidget->children();
    const QObjectList::const_iterator cend = children.constEnd();
    for (QObjectList::const_iterator it = children.constBegin(); it != cend; ++it) {
        QObject *o = *it;
        if (!o->isWidgetType())
            if (QStackedWidgetEventFilter *ef = qobject_cast<QStackedWidgetEventFilter *>(o))
                return ef;
    }
    return 0;
}

QMenu *QStackedWidgetEventFilter::addStackedWidgetContextMenuActions(const QStackedWidget *stackedWidget, QMenu *popup)
{
    QStackedWidgetEventFilter *filter = eventFilterOf(stackedWidget);
    if (!filter)
        return 0;
    return filter->addContextMenuActions(popup);
}

void QStackedWidgetEventFilter::removeCurrentPage()
{
    if (stackedWidget()->currentIndex() == -1)
        return;

    if (QDesignerFormWindowInterface *fw = QDesignerFormWindowInterface::findFormWindow(stackedWidget())) {
        qdesigner_internal::DeleteStackedWidgetPageCommand *cmd = new qdesigner_internal::DeleteStackedWidgetPageCommand(fw);
        cmd->init(stackedWidget());
        fw->commandHistory()->push(cmd);
    }
}

void QStackedWidgetEventFilter::changeOrder()
{
    QDesignerFormWindowInterface *fw = QDesignerFormWindowInterface::findFormWindow(stackedWidget());

    if (!fw)
        return;

    const QWidgetList oldPages = qdesigner_internal::OrderDialog::pagesOfContainer(fw->core(), stackedWidget());
    const int pageCount = oldPages.size();
    if (pageCount < 2)
        return;

    qdesigner_internal::OrderDialog dlg(fw);
    dlg.setPageList(oldPages);
    if (dlg.exec() == QDialog::Rejected)
        return;

    const QWidgetList newPages = dlg.pageList();
    if (newPages == oldPages)
        return;

    fw->beginCommand(tr("Change Page Order"));
    for(int i=0; i < pageCount; ++i) {
        if (newPages.at(i) == stackedWidget()->widget(i))
            continue;
        qdesigner_internal::MoveStackedWidgetCommand *cmd = new qdesigner_internal::MoveStackedWidgetCommand(fw);
        cmd->init(stackedWidget(), newPages.at(i), i);
        fw->commandHistory()->push(cmd);
    }
    fw->endCommand();
}

void QStackedWidgetEventFilter::addPage()
{
    if (QDesignerFormWindowInterface *fw = QDesignerFormWindowInterface::findFormWindow(stackedWidget())) {
        qdesigner_internal::AddStackedWidgetPageCommand *cmd = new qdesigner_internal::AddStackedWidgetPageCommand(fw);
        cmd->init(stackedWidget(), qdesigner_internal::AddStackedWidgetPageCommand::InsertBefore);
        fw->commandHistory()->push(cmd);
    }
}

void QStackedWidgetEventFilter::addPageAfter()
{
    if (QDesignerFormWindowInterface *fw = QDesignerFormWindowInterface::findFormWindow(stackedWidget())) {
        qdesigner_internal::AddStackedWidgetPageCommand *cmd = new qdesigner_internal::AddStackedWidgetPageCommand(fw);
        cmd->init(stackedWidget(), qdesigner_internal::AddStackedWidgetPageCommand::InsertAfter);
        fw->commandHistory()->push(cmd);
    }
}

void QStackedWidgetEventFilter::gotoPage(int page) {
    // Are we on a form or in a preview?
    if (QDesignerFormWindowInterface *fw = QDesignerFormWindowInterface::findFormWindow(stackedWidget())) {
        qdesigner_internal::SetPropertyCommand *cmd = new  qdesigner_internal::SetPropertyCommand(fw);
        cmd->init(stackedWidget(), QStringLiteral("currentIndex"), page);
        fw->commandHistory()->push(cmd);
        fw->emitSelectionChanged(); // Magically prevent an endless loop triggered by auto-repeat.
        updateButtons();
    } else {
        QStackedWidgetPreviewEventFilter::gotoPage(page);
    }
}

QMenu *QStackedWidgetEventFilter::addContextMenuActions(QMenu *popup)
{
    QMenu *pageMenu = 0;
    const int count = stackedWidget()->count();
    const bool hasSeveralPages = count > 1;
    m_actionDeletePage->setEnabled(count);
    if (count) {
        const QString pageSubMenuLabel = tr("Page %1 of %2").arg(stackedWidget()->currentIndex() + 1).arg(count);
        pageMenu = popup->addMenu(pageSubMenuLabel);
        pageMenu->addAction(m_actionDeletePage);
        // Set up promotion menu for current widget.
        if (QWidget *page =  stackedWidget()->currentWidget ()) {
            m_pagePromotionTaskMenu->setWidget(page);
            m_pagePromotionTaskMenu->addActions(QDesignerFormWindowInterface::findFormWindow(stackedWidget()),
                                                qdesigner_internal::PromotionTaskMenu::SuppressGlobalEdit,
                                                pageMenu);
        }
        QMenu *insertPageMenu = popup->addMenu(tr("Insert Page"));
        insertPageMenu->addAction(m_actionInsertPageAfter);
        insertPageMenu->addAction(m_actionInsertPage);
    } else {
        QAction *insertPageAction = popup->addAction(tr("Insert Page"));
        connect(insertPageAction, &QAction::triggered, this, &QStackedWidgetEventFilter::addPage);
    }
    popup->addAction(m_actionNextPage);
    m_actionNextPage->setEnabled(hasSeveralPages);
    popup->addAction(m_actionPreviousPage);
    m_actionPreviousPage->setEnabled(hasSeveralPages);
    popup->addAction(m_actionChangePageOrder);
    m_actionChangePageOrder->setEnabled(hasSeveralPages);
    popup->addSeparator();
    return pageMenu;
}

// --------  QStackedWidgetPropertySheet

static const char *pagePropertyName = "currentPageName";

QStackedWidgetPropertySheet::QStackedWidgetPropertySheet(QStackedWidget *object, QObject *parent) :
    QDesignerPropertySheet(object, parent),
    m_stackedWidget(object)
{
    createFakeProperty(QLatin1String(pagePropertyName), QString());
}

bool QStackedWidgetPropertySheet::isEnabled(int index) const
{
    if (propertyName(index) != QLatin1String(pagePropertyName))
        return QDesignerPropertySheet::isEnabled(index);
    return  m_stackedWidget->currentWidget() != 0;
}

void QStackedWidgetPropertySheet::setProperty(int index, const QVariant &value)
{
    if (propertyName(index) == QLatin1String(pagePropertyName)) {
        if (QWidget *w = m_stackedWidget->currentWidget())
            w->setObjectName(value.toString());
    } else {
        QDesignerPropertySheet::setProperty(index, value);
    }
}

QVariant QStackedWidgetPropertySheet::property(int index) const
{
    if (propertyName(index) == QLatin1String(pagePropertyName)) {
        if (const QWidget *w = m_stackedWidget->currentWidget())
            return w->objectName();
        return QString();
    }
    return QDesignerPropertySheet::property(index);
}

bool QStackedWidgetPropertySheet::reset(int index)
{
    if (propertyName(index) == QLatin1String(pagePropertyName)) {
        setProperty(index, QString());
        return true;
    }
    return QDesignerPropertySheet::reset(index);
}

bool QStackedWidgetPropertySheet::checkProperty(const QString &propertyName)
{
    return propertyName != QLatin1String(pagePropertyName);
}

QT_END_NAMESPACE
