/*
 *  Copyright (C) 2010 Andriy Rysin (rysin@kde.org)
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */


#ifndef X11_HELPER_H_
#define X11_HELPER_H_

#include <QtGui/QKeySequence>
#include <QtCore/QString>
#include <QtCore/QStringList>
#include <QtGui/QWidget>


class XEventNotifier : public QWidget {
    Q_OBJECT

Q_SIGNALS:
    void layoutChanged();
    void layoutMapChanged();

public:
    XEventNotifier(QWidget* parent=NULL);
    virtual ~XEventNotifier() {}

    virtual void start();
    virtual void stop();

protected:
    bool x11Event(XEvent * e);
    virtual bool processOtherEvents(XEvent* e);
    virtual bool processXkbEvents(XEvent* e);

private:
    int registerForXkbEvents(Display* display);
    bool isXkbEvent(XEvent* event);
    bool isGroupSwitchEvent(XEvent* event);
    bool isLayoutSwitchEvent(XEvent* event);

    int xkbOpcode;
};

class XkbConfig {
public:
    QString keyboardModel;
    QStringList layouts;
    QStringList variants;
    QStringList options;

    bool isValid() { return ! layouts.empty(); }
};


class LayoutUnit {
public:
    static const int MAX_LABEL_LENGTH;

    //TODO: move these to private?
    QString layout;
    QString variant;

    LayoutUnit() {}
    explicit LayoutUnit(const QString& fullLayoutName);
    LayoutUnit(const QString& layout_, const QString& variant_) {
        layout = layout_;
        variant = variant_;
    }
    /*explicit*/ LayoutUnit(const LayoutUnit& layoutUnit) {
        layout = layoutUnit.layout;
        variant = layoutUnit.variant;
        displayName = layoutUnit.displayName;
        shortcut = layoutUnit.shortcut;
    }

    QString getRawDisplayName() const { return displayName; }
    QString getDisplayName() const { return !displayName.isEmpty() ? displayName :  layout; }
    void setDisplayName(const QString& name) { displayName = name; }

    void setShortcut(const QKeySequence& shortcut) { this->shortcut = shortcut; }
    QKeySequence getShortcut() const { return shortcut; }

    bool isEmpty() const { return layout.isEmpty(); }
    bool isValid() const { return ! isEmpty(); }
    bool operator==(const LayoutUnit& layoutItem) const {
        return layout==layoutItem.layout && variant==layoutItem.variant;
    }
    bool operator!=(const LayoutUnit& layoutItem) const {
        return ! (*this == layoutItem);
    }
    QString toString() const;

private:
    QString displayName;
    QKeySequence shortcut;
};

class LayoutSet {
public:
    QList<LayoutUnit> layouts;
    LayoutUnit currentLayout;

    LayoutSet() {}

    LayoutSet(const LayoutSet& currentLayouts) {
        this->layouts = currentLayouts.layouts;
        this->currentLayout = currentLayouts.currentLayout;
    }

    bool isValid() const {
        return currentLayout.isValid() && layouts.contains(currentLayout);
    }

    bool operator == (const LayoutSet& currentLayouts) const {
        return this->layouts == currentLayouts.layouts
            && this->currentLayout == currentLayouts.currentLayout;
    }

    LayoutSet& operator = (const LayoutSet& currentLayouts) {
        this->layouts = currentLayouts.layouts;
        this->currentLayout = currentLayouts.currentLayout;
        return *this;
    }

    QString toString() const {
        QString str(currentLayout.toString());
        str += ": ";
        foreach(const LayoutUnit& layoutUnit, layouts) {
            str += layoutUnit.toString() + " ";
        }
        return str;
    }

    static QString toString(const QList<LayoutUnit>& layoutUnits) {
        QString str;
        foreach(const LayoutUnit& layoutUnit, layoutUnits) {
            str += layoutUnit.toString() + ",";
        }
        return str;
    }
};

class X11Helper
{
public:
    static int MAX_GROUP_COUNT;
    static int ARTIFICIAL_GROUP_LIMIT_COUNT;

    static const char* LEFT_VARIANT_STR;
    static const char* RIGHT_VARIANT_STR;

    static bool xkbSupported(int* xkbOpcode);

    static void switchToNextLayout();
    static void scrollLayouts(int delta);
    static bool isDefaultLayout();
    static bool setDefaultLayout();
    static bool setLayout(const LayoutUnit& layout);
    static LayoutUnit getCurrentLayout();
    static LayoutSet getCurrentLayouts();
    static QList<LayoutUnit> getLayoutsList();
    static QStringList getLayoutsListAsString(const QList<LayoutUnit>& layoutsList);

    enum FetchType { ALL, LAYOUTS_ONLY, MODEL_ONLY };
    static bool getGroupNames(Display* dpy, XkbConfig* xkbConfig, FetchType fetchType);

private:
    static unsigned int getGroup();
    static bool setGroup(unsigned int group);
};

#endif /* X11_HELPER_H_ */