/*
 * Copyright 2014  Martin Gräßlin <mgraesslin@kde.org>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) version 3, or any
 * later version accepted by the membership of KDE e.V. (or its
 * successor approved by the membership of KDE e.V.), which shall
 * act as a proxy defined in Section 6 of version 3 of the license.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 */
#ifndef KDECORATION2_DECORATED_CLIENT_H
#define KDECORATION2_DECORATED_CLIENT_H

#include <kdecoration2/kdecoration2_export.h>
#include "decorationdefines.h"

#include <QObject>
#include <QPointer>
#include <QtGui/qwindowdefs.h>
#include <QIcon>
#include <QPalette>
#include <QFont>

#include <memory>

namespace KDecoration2
{

class Decoration;
class DecorationBridge;
class DecoratedClientPrivate;

/**
 * @brief The Client which gets decorated.
 *
 * The DecoratedClient provides access to all the properties relevant for decorating the Client.
 * Each DecoratedClient is bound to one Decoration and each Decoration is bound to this one
 * DecoratedClient.
 *
 * The DecoratedClient only exports properties, it does not provide any means to change the state.
 * To change state one needs to call the methods on Decoration. This is as the backend might
 * disallow state changes. Therefore any changes should be bound to the change signals of the
 * DecoratedClient and not be bound to state changes of input elements (such as a button).
 */
class KDECORATIONS2_EXPORT DecoratedClient : public QObject
{
    Q_OBJECT
    /**
     * The Decoration of this DecoratedClient
     **/
    Q_PROPERTY(KDecoration2::Decoration *decoration READ decoration CONSTANT)
    /**
     * Whether the DecoratedClient is active (has focus) or is inactive.
     **/
    Q_PROPERTY(bool active READ isActive NOTIFY activeChanged)
    /**
     * The caption of the DecoratedClient.
     **/
    Q_PROPERTY(QString caption READ caption NOTIFY captionChanged)
    /**
     * The virtual desktop of the DecoratedClient. The special value @c -1 means on all
     * desktops. For this prefer using the property onAllDesktops.
     **/
    Q_PROPERTY(int desktop READ desktop NOTIFY desktopChanged)
    /**
     * Whether the DecoratedClient is on all desktops or on just one.
     **/
    Q_PROPERTY(bool onAllDesktops READ isOnAllDesktops NOTIFY onAllDesktopsChanged)
    /**
     * Whether the DecoratedClient is shaded. Shaded means that the actual content is
     * not visible, only the Decoration is visible.
     **/
    Q_PROPERTY(bool shaded READ isShaded NOTIFY shadedChanged)
    /**
     * The icon of the DecoratedClient. This can be used as the icon for the window menu button.
     **/
    Q_PROPERTY(QIcon icon READ icon NOTIFY iconChanged)
    /**
     * Whether the DecoratedClient is maximized. A DecoratedClient is maximized if it is both
     * maximizedHorizontally and maximizedVertically. The Decoration of a maximized DecoratedClient
     * should only consist of the title bar area.
     **/
    Q_PROPERTY(bool maximized READ isMaximized NOTIFY maximizedChanged)
    /**
     * Whether the DecoratedClient is maximized horizontally. A horizontally maximized DecoratedClient
     * uses the maximal possible width.
     **/
    Q_PROPERTY(bool maximizedHorizontally READ isMaximizedHorizontally NOTIFY maximizedHorizontallyChanged)
    /**
     * Whether the DecoratedClient is maximized vertically. A vertically maximized DecoratedClient
     * uses the maximal possible height.
     **/
    Q_PROPERTY(bool maximizedVertically READ isMaximizedVertically NOTIFY maximizedVerticallyChanged)
    /**
     * Whether the DecoratedClient is set to be kept above other DecoratedClients. There can be multiple
     * DecoratedClients which are set to be kept above.
     **/
    Q_PROPERTY(bool keepAbove READ isKeepAbove NOTIFY keepAboveChanged)
    /**
     * Whether the DecoratedClient is set to be kept below other DecoratedClients. There can be multiple
     * DecoratedClients which are set to be kept below.
     **/
    Q_PROPERTY(bool keepBelow READ isKeepBelow NOTIFY keepBelowChanged)

    /**
     * Whether the DecoratedClient can be closed. If this property is @c false a DecorationButton
     * for closing the DecoratedClient should be disabled.
     **/
    Q_PROPERTY(bool closeable READ isCloseable NOTIFY closeableChanged)
    /**
     * Whether the DecoratedClient can be maximized. If this property is @c false a DecorationButton
     * for maximizing the DecoratedClient should be disabled.
     **/
    Q_PROPERTY(bool maximizeable READ isMaximizeable NOTIFY maximizeableChanged)
    /**
     * Whether the DecoratedClient can be minimized. If this property is @c false a DecorationButton
     * for minimizing the DecoratedClient should be disabled.
     **/
    Q_PROPERTY(bool minimizeable READ isMinimizeable NOTIFY minimizeableChanged)
    /**
     * Whether the DecoratedClient provides context help.
     * The Decoration should only show a context help button if this property is @c true.
     **/
    Q_PROPERTY(bool providesContextHelp READ providesContextHelp NOTIFY providesContextHelpChanged)
    /**
     * Whether the DecoratedClient is a modal dialog.
     **/
    Q_PROPERTY(bool modal READ isModal CONSTANT)
    /**
     * Whether the DecoratedClient can be shaded. If this property is @c false a DecorationButton
     * for shading the DecoratedClient should be disabled.
     **/
    Q_PROPERTY(bool shadeable READ isShadeable NOTIFY shadeableChanged)
    /**
     * Whether the DecoratedClient can be moved.
     **/
    Q_PROPERTY(bool moveable READ isMoveable NOTIFY moveableChanged)
    /**
     * Whether the DecoratedClient can be resized.
     **/
    Q_PROPERTY(bool resizeable READ isResizeable NOTIFY resizeableChanged)

    /**
     * The width of the DecoratedClient.
     **/
    Q_PROPERTY(int width READ width NOTIFY widthChanged)
    /**
     * The height of the DecoratedClient.
     **/
    Q_PROPERTY(int height READ height NOTIFY heightChanged)
    /**
     * The palette this DecoratedClient uses. The palette might be different for each
     * DecoratedClient and the Decoration should honor the palette.
     **/
    Q_PROPERTY(QPalette palette READ palette NOTIFY paletteChanged)
    /**
     * The Edges which are adjacent to a screen edge. E.g. for a maximized DecoratedClient this
     * will include all Edges. The Decoration can use this information to hide borders.
     **/
    Q_PROPERTY(Qt::Edges adjacentScreenEdges READ adjacentScreenEdges NOTIFY adjacentScreenEdgesChanged)
    /**
     * Whether the DecoratedClient has an application menu
     * @since 5.9
     */
    Q_PROPERTY(bool hasApplicationMenu READ hasApplicationMenu NOTIFY hasApplicationMenuChanged)
    /**
     * Whether the application menu for this DecoratedClient is currently shown to the user
     * The Decoration can use this information to highlight the respective button.
     * @since 5.9
     */
    Q_PROPERTY(bool applicationMenuActive READ isApplicationMenuActive NOTIFY applicationMenuActiveChanged)

    // TODO: properties for windowId and decorationId?

public:
    DecoratedClient() = delete;
    ~DecoratedClient();
    bool isActive() const;
    QString caption() const;
    int desktop() const;
    bool isOnAllDesktops() const;
    bool isShaded() const;
    QIcon icon() const;
    bool isMaximized() const;
    bool isMaximizedHorizontally() const;
    bool isMaximizedVertically() const;
    bool isKeepAbove() const;
    bool isKeepBelow() const;

    bool isCloseable() const;
    bool isMaximizeable() const;
    bool isMinimizeable() const;
    bool providesContextHelp() const;
    bool isModal() const;
    bool isShadeable() const;
    bool isMoveable() const;
    bool isResizeable() const;

    Qt::Edges adjacentScreenEdges() const;

    WId windowId() const;
    WId decorationId() const;

    int width() const;
    int height() const;

    QPointer<Decoration> decoration() const;
    QPalette palette() const;
    /**
     * Used to get colors in QPalette.
     * @param group The color group
     * @param role The color role
     * @return palette().color(group, role)
     * @since 5.3
     **/
    QColor color(QPalette::ColorGroup group, QPalette::ColorRole role) const;
    /**
     * Used to get additional colors that are not in QPalette.
     * @param group The color group
     * @param role The color role
     * @return The color if provided for combination of group and role, otherwise invalid QColor.
     * @since 5.3
     **/
    QColor color(ColorGroup group, ColorRole role) const;

    /**
     * Whether the DecoratedClient has an application menu
     * @since 5.9
     */
    bool hasApplicationMenu() const;
    /**
     * Whether the application menu for this DecoratedClient is currently shown to the user
     * The Decoration can use this information to highlight the respective button.
     * @since 5.9
     */
    bool isApplicationMenuActive() const;

    /**
     * Request the application menu to be shown to the user
     * @param actionId The DBus menu ID of the action that should be highlighted, 0 for none.
     */
    void showApplicationMenu(int actionId);

Q_SIGNALS:
    void activeChanged(bool);
    void captionChanged(QString);
    void desktopChanged(int);
    void onAllDesktopsChanged(bool);
    void shadedChanged(bool);
    void iconChanged(QIcon);
    void maximizedChanged(bool);
    void maximizedHorizontallyChanged(bool);
    void maximizedVerticallyChanged(bool);
    void keepAboveChanged(bool);
    void keepBelowChanged(bool);

    void closeableChanged(bool);
    void maximizeableChanged(bool);
    void minimizeableChanged(bool);
    void providesContextHelpChanged(bool);
    void shadeableChanged(bool);
    void moveableChanged(bool);
    void resizeableChanged(bool);

    void widthChanged(int);
    void heightChanged(int);
    void paletteChanged(const QPalette &palette);
    void adjacentScreenEdgesChanged(Qt::Edges edges);

    void hasApplicationMenuChanged(bool);
    void applicationMenuActiveChanged(bool);

private:
    friend class Decoration;
    DecoratedClient(Decoration *parent, DecorationBridge *bridge);
    const std::unique_ptr<DecoratedClientPrivate> d;
};

} // namespace

#endif
