// Copyright (C) 2020 Uwe Kindler
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-2.1-or-later OR GPL-3.0-or-later

#pragma once

#include "ads_globals.h"

#include "autohidetab.h"

#include <QScrollArea>

class QXmlStreamWriter;

namespace ADS {

struct AutoHideSideBarPrivate;
class DockContainerWidgetPrivate;
class DockContainerWidget;
class AutoHideTab;
class AutoHideDockContainer;
class DockingStateReader;

/**
 * Side tab bar widget that is shown at the edges of a dock container.
 * The tab bar is only visible, if it contains visible content, that means if
 * it contains visible tabs. If it is empty or all tabs are hidden, then the
 * side bar is also hidden. As soon as one single tab becomes visible, this
 * tab bar will be shown.
 * The CAutoHideSideBar uses a QScrollArea here, to enable proper resizing.
 * If the side bar contains many tabs, then the tabs are simply clipped - this
 * is the same like in visual studio
 */
class ADS_EXPORT AutoHideSideBar : public QScrollArea
{
    Q_OBJECT
    Q_PROPERTY(int sideBarLocation READ sideBarLocation)
    Q_PROPERTY(Qt::Orientation orientation READ orientation)
    Q_PROPERTY(int spacing READ spacing WRITE setSpacing)

private:
    AutoHideSideBarPrivate* d; ///< private data (pimpl)
    friend struct AutoHideSideBarPrivate;
    friend class DockWidgetSideTab;
    friend DockContainerWidgetPrivate;
    friend DockContainerWidget;

protected:
    virtual bool eventFilter(QObject *watched, QEvent *event) override;

    /**
     * Saves the state into the given stream
     */
    void saveState(QXmlStreamWriter &stream) const;

    /**
     * Inserts the given dock widget tab at the given position.
     * An Index value of -1 appends the side tab at the end.
     */
    void insertTab(int index, AutoHideTab *sideTab);

public:
    using Super = QScrollArea;

    /**
     * Default Constructor
     */
    AutoHideSideBar(DockContainerWidget *parent, SideBarLocation area);

    /**
     * Virtual Destructor
     */
    virtual ~AutoHideSideBar();

    /**
     * Removes the given DockWidgetSideTab from the tabbar
     */
    void removeTab(AutoHideTab *sideTab);

    /**
     * Insert dock widget into the side bar. The function creates the auto hide dock container,
     * inserts the auto hide tab
     */
    AutoHideDockContainer *insertDockWidget(int index, DockWidget *dockWidget);

    /**
     * Removes the auto hide widget from this side bar
     */
    void removeAutoHideWidget(AutoHideDockContainer *autoHideWidget);

    /**
     * Adds the given AutoHideWidget to this sidebar. If the AutoHideWidget is in another sidebar,
     * then it will be removed from this sidebar.
     */
    void addAutoHideWidget(AutoHideDockContainer *autoHideWidget, int index = TabDefaultInsertIndex);

    /**
     * Returns orientation of side tab.
     */
    Qt::Orientation orientation() const;

    /**
     * Get the side tab widget at position, returns nullptr if it's out of bounds.
     */
    AutoHideTab *tab(int index) const;

    /**
     * Returns the tab at the given position.
     * Returns -1 if the position is left of the first tab and count() if the position is right
     * of the last tab. Returns InvalidTabIndex (-2) to indicate an invalid value.
     */
    int tabAt(const QPoint &pos) const;

    /**
     * Returns the tab insertion index for the given mouse cursor position.
     */
    int tabInsertIndexAt(const QPoint &pos) const;

    /**
     * Returns the index of the given tab.
     */
    int indexOfTab(const AutoHideTab &tab) const;

    /**
     * Gets the count of the tab widgets.
     */
    int count() const;

    /**
     * Returns the number of visible tabs to its parent widget.
     */
    int visibleTabCount() const;

    /**
     * Returns true, if the sidebar contains visible tabs to its parent widget.
     * The function returns as soon as it finds the first visible tab. That means, if you just want
     * to find out if there are visible tabs then this function is quicker than visibleTabCount().
     */
    bool hasVisibleTabs() const;

    /**
     * Getter for side tab bar area property
     */
    SideBarLocation sideBarLocation() const;

    /**
     * Overrides the minimumSizeHint() function of QScrollArea
     * The minimumSizeHint() is bigger than the sizeHint () for the scroll
     * area because even if the scrollbars are invisible, the required speace
     * is reserved in the minimumSizeHint(). This override simply returns sizeHint();
     */
    virtual QSize minimumSizeHint() const override;

    /**
     * The function provides a sizeHint that matches the height of the internal viewport.
     */
    virtual QSize sizeHint() const override;

    /**
     * Getter for spacing property - returns the spacing of the tabs
     */
    int spacing() const;

    /**
     * Setter for spacing property - sets the spacing
     */
    void setSpacing(int spacing);

    /**
     * Returns the dock container that hosts this sideBar()
     */
    DockContainerWidget *dockContainer() const;
};

} // namespace ADS