/****************************************************************************
**
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** This file is part of the plugins of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL21$
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** accordance with the commercial license agreement provided with the
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** use the contact form at http://qt.digia.com/contact-us.
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****************************************************************************/

#ifndef QWINDOWSINPUTCONTEXT_H
#define QWINDOWSINPUTCONTEXT_H

#include "qtwindows_additional.h"

#include <QtCore/QPointer>
#include <qpa/qplatforminputcontext.h>

QT_BEGIN_NAMESPACE

class QInputMethodEvent;

class QWindowsInputContext : public QPlatformInputContext
{
    Q_OBJECT

    struct CompositionContext
    {
        CompositionContext();

        HWND hwnd;
        bool haveCaret;
        QString composition;
        int position;
        bool isComposing;
        QPointer<QObject> focusObject;
    };
public:
    explicit QWindowsInputContext();
    ~QWindowsInputContext();

    bool hasCapability(Capability capability) const Q_DECL_OVERRIDE;
    void reset() Q_DECL_OVERRIDE;
    void update(Qt::InputMethodQueries) Q_DECL_OVERRIDE;
    void invokeAction(QInputMethod::Action, int cursorPosition) Q_DECL_OVERRIDE;
    void setFocusObject(QObject *object) Q_DECL_OVERRIDE;

    static QWindowsInputContext *instance();

    bool startComposition(HWND hwnd);
    bool composition(HWND hwnd, LPARAM lParam);
    bool endComposition(HWND hwnd);

    int reconvertString(RECONVERTSTRING *reconv);

    bool handleIME_Request(WPARAM wparam, LPARAM lparam, LRESULT *result);

private slots:
    void cursorRectChanged();

private:
    void initContext(HWND hwnd, QObject *focusObject);
    void doneContext();
    void startContextComposition();
    void endContextComposition();

    const DWORD m_WM_MSIME_MOUSE;
    static HIMC m_defaultContext;
    CompositionContext m_compositionContext;
    bool m_endCompositionRecursionGuard;
};

QT_END_NAMESPACE

#endif // QWINDOWSINPUTCONTEXT_H
