/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** Contact: Nokia Corporation (qt-info@nokia.com)
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** This file is part of the QtGui module of the Qt Toolkit.
**
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** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
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** additional rights.  These rights are described in the Nokia Qt LGPL
** Exception version 1.1, included in the file LGPL_EXCEPTION.txt in this
** package.
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** Nokia at qt-info@nokia.com.
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****************************************************************************/

#include "qwininputcontext_p.h"
#include "qinputcontext_p.h"

#include "qfont.h"
#include "qwidget.h"
#include "qapplication.h"
#include "qlibrary.h"
#include "qevent.h"
#include "qtextformat.h"

//#define Q_IME_DEBUG

/* Active Input method support on Win95/98/NT */
#include <objbase.h>
#include <initguid.h>

#ifdef Q_IME_DEBUG
#include "qdebug.h"
#endif

#if defined(Q_OS_WINCE)
extern void qt_wince_show_SIP(bool show);   // defined in qguifunctions_wince.cpp
#endif

QT_BEGIN_NAMESPACE

extern bool qt_sendSpontaneousEvent(QObject*, QEvent*);


DEFINE_GUID(IID_IActiveIMMApp,
0x08c0e040, 0x62d1, 0x11d1, 0x93, 0x26, 0x0, 0x60, 0xb0, 0x67, 0xb8, 0x6e);



DEFINE_GUID(CLSID_CActiveIMM,
0x4955DD33, 0xB159, 0x11d0, 0x8F, 0xCF, 0x0, 0xAA, 0x00, 0x6B, 0xCC, 0x59);



DEFINE_GUID(IID_IActiveIMMMessagePumpOwner,
0xb5cf2cfa, 0x8aeb, 0x11d1, 0x93, 0x64, 0x0, 0x60, 0xb0, 0x67, 0xb8, 0x6e);



interface IEnumRegisterWordW;
interface IEnumInputContext;


bool qt_sendSpontaneousEvent(QObject*, QEvent*);


#define IFMETHOD HRESULT STDMETHODCALLTYPE

interface IActiveIMMApp : public IUnknown
{
public:
    virtual IFMETHOD AssociateContext(HWND hWnd, HIMC hIME, HIMC __RPC_FAR *phPrev) = 0;
    virtual IFMETHOD dummy_ConfigureIMEA() = 0;
    virtual IFMETHOD ConfigureIMEW(HKL hKL, HWND hWnd, DWORD dwMode, REGISTERWORDW __RPC_FAR *pData) = 0;
    virtual IFMETHOD CreateContext(HIMC __RPC_FAR *phIMC) = 0;
    virtual IFMETHOD DestroyContext(HIMC hIME) = 0;
    virtual IFMETHOD dummy_EnumRegisterWordA() = 0;
    virtual IFMETHOD EnumRegisterWordW(HKL hKL, LPWSTR szReading, DWORD dwStyle, LPWSTR szRegister, LPVOID pData,
        IEnumRegisterWordW __RPC_FAR *__RPC_FAR *pEnum) = 0;
    virtual IFMETHOD dummy_EscapeA() = 0;
    virtual IFMETHOD EscapeW(HKL hKL, HIMC hIMC, UINT uEscape, LPVOID pData, LRESULT __RPC_FAR *plResult) = 0;
    virtual IFMETHOD dummy_GetCandidateListA() = 0;
    virtual IFMETHOD GetCandidateListW(HIMC hIMC, DWORD dwIndex, UINT uBufLen, CANDIDATELIST __RPC_FAR *pCandList,
        UINT __RPC_FAR *puCopied) = 0;
    virtual IFMETHOD dummy_GetCandidateListCountA() = 0;
    virtual IFMETHOD GetCandidateListCountW(HIMC hIMC, DWORD __RPC_FAR *pdwListSize, DWORD __RPC_FAR *pdwBufLen) = 0;
    virtual IFMETHOD GetCandidateWindow(HIMC hIMC, DWORD dwIndex, CANDIDATEFORM __RPC_FAR *pCandidate) = 0;
    virtual IFMETHOD dummy_GetCompositionFontA() = 0;
    virtual IFMETHOD GetCompositionFontW(HIMC hIMC, LOGFONTW __RPC_FAR *plf) = 0;
    virtual IFMETHOD dummy_GetCompositionStringA() = 0;
    virtual IFMETHOD GetCompositionStringW(HIMC hIMC, DWORD dwIndex, DWORD dwBufLen, LONG __RPC_FAR *plCopied, LPVOID pBuf) = 0;
    virtual IFMETHOD GetCompositionWindow(HIMC hIMC, COMPOSITIONFORM __RPC_FAR *pCompForm) = 0;
    virtual IFMETHOD GetContext(HWND hWnd, HIMC __RPC_FAR *phIMC) = 0;
    virtual IFMETHOD dummy_GetConversionListA() = 0;
    virtual IFMETHOD GetConversionListW(HKL hKL, HIMC hIMC, LPWSTR pSrc, UINT uBufLen, UINT uFlag,
        CANDIDATELIST __RPC_FAR *pDst, UINT __RPC_FAR *puCopied) = 0;
    virtual IFMETHOD GetConversionStatus(HIMC hIMC, DWORD __RPC_FAR *pfdwConversion, DWORD __RPC_FAR *pfdwSentence) = 0;
    virtual IFMETHOD GetDefaultIMEWnd(HWND hWnd, HWND __RPC_FAR *phDefWnd) = 0;
    virtual IFMETHOD dummy_GetDescriptionA() = 0;
    virtual IFMETHOD GetDescriptionW(HKL hKL, UINT uBufLen, LPWSTR szDescription, UINT __RPC_FAR *puCopied) = 0;
    virtual IFMETHOD dummy_GetGuideLineA() = 0;
    virtual IFMETHOD GetGuideLineW(HIMC hIMC, DWORD dwIndex, DWORD dwBufLen, LPWSTR pBuf, DWORD __RPC_FAR *pdwResult) = 0;
    virtual IFMETHOD dummy_GetIMEFileNameA() = 0;
    virtual IFMETHOD GetIMEFileNameW(HKL hKL, UINT uBufLen, LPWSTR szFileName, UINT __RPC_FAR *puCopied) = 0;
    virtual IFMETHOD GetOpenStatus(HIMC hIMC) = 0;
    virtual IFMETHOD GetProperty(HKL hKL, DWORD fdwIndex, DWORD __RPC_FAR *pdwProperty) = 0;
    virtual IFMETHOD dummy_GetRegisterWordStyleA() = 0;
    virtual IFMETHOD GetRegisterWordStyleW(HKL hKL, UINT nItem, STYLEBUFW __RPC_FAR *pStyleBuf, UINT __RPC_FAR *puCopied) = 0;
    virtual IFMETHOD GetStatusWindowPos(HIMC hIMC, POINT __RPC_FAR *pptPos) = 0;
    virtual IFMETHOD GetVirtualKey(HWND hWnd, UINT __RPC_FAR *puVirtualKey) = 0;
    virtual IFMETHOD dummy_InstallIMEA() = 0;
    virtual IFMETHOD InstallIMEW(LPWSTR szIMEFileName, LPWSTR szLayoutText, HKL __RPC_FAR *phKL) = 0;
    virtual IFMETHOD IsIME(HKL hKL) = 0;
    virtual IFMETHOD dummy_IsUIMessageA() = 0;
    virtual IFMETHOD IsUIMessageW(HWND hWndIME, UINT msg, WPARAM wParam, LPARAM lParam) = 0;
    virtual IFMETHOD NotifyIME(HIMC hIMC, DWORD dwAction, DWORD dwIndex, DWORD dwValue) = 0;
    virtual IFMETHOD dummy_RegisterWordA() = 0;
    virtual IFMETHOD RegisterWordW(HKL hKL, LPWSTR szReading, DWORD dwStyle, LPWSTR szRegister) = 0;
    virtual IFMETHOD ReleaseContext(HWND hWnd, HIMC hIMC) = 0;
    virtual IFMETHOD SetCandidateWindow(HIMC hIMC, CANDIDATEFORM __RPC_FAR *pCandidate) = 0;
    virtual IFMETHOD SetCompositionFontA(HIMC hIMC, LOGFONTA __RPC_FAR *plf) = 0;
    virtual IFMETHOD SetCompositionFontW(HIMC hIMC, LOGFONTW __RPC_FAR *plf) = 0;
    virtual IFMETHOD dummy_SetCompositionStringA() = 0;
    virtual IFMETHOD SetCompositionStringW(HIMC hIMC, DWORD dwIndex, LPVOID pComp, DWORD dwCompLen,
        LPVOID pRead, DWORD dwReadLen) = 0;
    virtual IFMETHOD SetCompositionWindow(HIMC hIMC, COMPOSITIONFORM __RPC_FAR *pCompForm) = 0;
    virtual IFMETHOD SetConversionStatus(HIMC hIMC, DWORD fdwConversion, DWORD fdwSentence) = 0;
    virtual IFMETHOD SetOpenStatus(HIMC hIMC, BOOL fOpen) = 0;
    virtual IFMETHOD SetStatusWindowPos(HIMC hIMC, POINT __RPC_FAR *pptPos) = 0;
    virtual IFMETHOD SimulateHotKey(HWND hWnd, DWORD dwHotKeyID) = 0;
    virtual IFMETHOD dummy_UnregisterWordA() = 0;
    virtual IFMETHOD UnregisterWordW(HKL hKL, LPWSTR szReading, DWORD dwStyle, LPWSTR szUnregister) = 0;
    virtual IFMETHOD Activate(BOOL fRestoreLayout) = 0;
    virtual IFMETHOD Deactivate(void) = 0;
    virtual IFMETHOD OnDefWindowProc(HWND hWnd, UINT Msg, WPARAM wParam, LPARAM lParam, LRESULT __RPC_FAR *plResult) = 0;
    virtual IFMETHOD FilterClientWindows(ATOM __RPC_FAR *aaClassList, UINT uSize) = 0;
    virtual IFMETHOD dummy_GetCodePageA() = 0;
    virtual IFMETHOD GetLangId(HKL hKL, LANGID __RPC_FAR *plid) = 0;
    virtual IFMETHOD AssociateContextEx(HWND hWnd, HIMC hIMC, DWORD dwFlags) = 0;
    virtual IFMETHOD DisableIME(DWORD idThread) = 0;
    virtual IFMETHOD dummy_GetImeMenuItemsA() = 0;
    virtual IFMETHOD GetImeMenuItemsW(HIMC hIMC, DWORD dwFlags, DWORD dwType, /*IMEMENUITEMINFOW*/ void __RPC_FAR *pImeParentMenu,
        /*IMEMENUITEMINFOW*/ void __RPC_FAR *pImeMenu, DWORD dwSize, DWORD __RPC_FAR *pdwResult) = 0;
    virtual IFMETHOD EnumInputContext(DWORD idThread, IEnumInputContext __RPC_FAR *__RPC_FAR *ppEnum) = 0;
};

interface IActiveIMMMessagePumpOwner : public IUnknown
{
public:
    virtual IFMETHOD Start(void) = 0;
    virtual IFMETHOD End(void) = 0;
    virtual IFMETHOD OnTranslateMessage(const MSG __RPC_FAR *pMsg) = 0;
    virtual IFMETHOD Pause(DWORD __RPC_FAR *pdwCookie) = 0;
    virtual IFMETHOD Resume(DWORD dwCookie) = 0;
};


static IActiveIMMApp *aimm = 0;
static IActiveIMMMessagePumpOwner *aimmpump = 0;
static QString *imeComposition = 0;
static int        imePosition    = -1;
bool qt_use_rtl_extensions = false;
static bool haveCaret = false;

#ifndef LGRPID_INSTALLED
#define LGRPID_INSTALLED          0x00000001  // installed language group ids
#define LGRPID_SUPPORTED          0x00000002  // supported language group ids
#endif

#ifndef LGRPID_ARABIC
#define LGRPID_WESTERN_EUROPE        0x0001   // Western Europe & U.S.
#define LGRPID_CENTRAL_EUROPE        0x0002   // Central Europe
#define LGRPID_BALTIC                0x0003   // Baltic
#define LGRPID_GREEK                 0x0004   // Greek
#define LGRPID_CYRILLIC              0x0005   // Cyrillic
#define LGRPID_TURKISH               0x0006   // Turkish
#define LGRPID_JAPANESE              0x0007   // Japanese
#define LGRPID_KOREAN                0x0008   // Korean
#define LGRPID_TRADITIONAL_CHINESE   0x0009   // Traditional Chinese
#define LGRPID_SIMPLIFIED_CHINESE    0x000a   // Simplified Chinese
#define LGRPID_THAI                  0x000b   // Thai
#define LGRPID_HEBREW                0x000c   // Hebrew
#define LGRPID_ARABIC                0x000d   // Arabic
#define LGRPID_VIETNAMESE            0x000e   // Vietnamese
#define LGRPID_INDIC                 0x000f   // Indic
#define LGRPID_GEORGIAN              0x0010   // Georgian
#define LGRPID_ARMENIAN              0x0011   // Armenian
#endif

static DWORD WM_MSIME_MOUSE = 0;

QWinInputContext::QWinInputContext(QObject *parent)
    : QInputContext(parent), recursionGuard(false)
{
    if (QSysInfo::WindowsVersion < QSysInfo::WV_2000) {
        // try to get the Active IMM COM object on Win95/98/NT, where english versions don't
        // support the regular Windows input methods.
        if (CoCreateInstance(CLSID_CActiveIMM, NULL, CLSCTX_INPROC_SERVER,
            IID_IActiveIMMApp, (LPVOID *)&aimm) != S_OK) {
            aimm = 0;
        }
        if (aimm && (aimm->QueryInterface(IID_IActiveIMMMessagePumpOwner, (LPVOID *)&aimmpump) != S_OK ||
                        aimm->Activate(true) != S_OK)) {
            aimm->Release();
            aimm = 0;
            if (aimmpump)
                aimmpump->Release();
            aimmpump = 0;
        }
        if (aimmpump)
            aimmpump->Start();
    }

#ifndef Q_OS_WINCE
    QSysInfo::WinVersion ver = QSysInfo::windowsVersion();
    if (ver & QSysInfo::WV_NT_based  && ver >= QSysInfo::WV_VISTA) {
        // Since the IsValidLanguageGroup/IsValidLocale functions always return true on 
        // Vista, check the Keyboard Layouts for enabling RTL. 
        UINT nLayouts = GetKeyboardLayoutList(0, 0);
        if (nLayouts) {
            HKL *lpList = new HKL[nLayouts];
            GetKeyboardLayoutList(nLayouts, lpList);
            for (int i = 0; i<(int)nLayouts; i++) {
                WORD plangid = PRIMARYLANGID((quintptr)lpList[i]);
                if (plangid == LANG_ARABIC 
                    || plangid ==  LANG_HEBREW
                    || plangid ==  LANG_FARSI
#ifdef LANG_SYRIAC
                    || plangid ==  LANG_SYRIAC
#endif
                    ) {
                        qt_use_rtl_extensions = true;
                        break;
                }
            }
            delete []lpList;
        }
    } else {
	    // figure out whether a RTL language is installed
    	typedef BOOL(WINAPI *PtrIsValidLanguageGroup)(DWORD,DWORD);
    	PtrIsValidLanguageGroup isValidLanguageGroup = (PtrIsValidLanguageGroup)QLibrary::resolve(QLatin1String("kernel32"), "IsValidLanguageGroup");
    	if (isValidLanguageGroup) {
        	qt_use_rtl_extensions = isValidLanguageGroup(LGRPID_ARABIC, LGRPID_INSTALLED)
	            	                 || isValidLanguageGroup(LGRPID_HEBREW, LGRPID_INSTALLED);
    	}
    	qt_use_rtl_extensions |= IsValidLocale(MAKELCID(MAKELANGID(LANG_ARABIC, SUBLANG_DEFAULT), SORT_DEFAULT), LCID_INSTALLED)
        	                  || IsValidLocale(MAKELCID(MAKELANGID(LANG_HEBREW, SUBLANG_DEFAULT), SORT_DEFAULT), LCID_INSTALLED)
#ifdef LANG_SYRIAC
            	              || IsValidLocale(MAKELCID(MAKELANGID(LANG_SYRIAC, SUBLANG_DEFAULT), SORT_DEFAULT), LCID_INSTALLED)
#endif
                	          || IsValidLocale(MAKELCID(MAKELANGID(LANG_FARSI, SUBLANG_DEFAULT), SORT_DEFAULT), LCID_INSTALLED);
    }
#else
    qt_use_rtl_extensions = false;
#endif

    WM_MSIME_MOUSE = QT_WA_INLINE(RegisterWindowMessage(L"MSIMEMouseOperation"), RegisterWindowMessageA("MSIMEMouseOperation"));
}

QWinInputContext::~QWinInputContext()
{
    // release active input method if we have one
    if (aimm) {
        aimmpump->End();
        aimmpump->Release();
        aimm->Deactivate();
        aimm->Release();
        aimm = 0;
        aimmpump = 0;
    }
    delete imeComposition;
    imeComposition = 0;
}

static HWND getDefaultIMEWnd(HWND wnd)
{
    HWND ime_wnd;
    if(aimm)
        aimm->GetDefaultIMEWnd(wnd, &ime_wnd);
    else
        ime_wnd = ImmGetDefaultIMEWnd(wnd);
    return ime_wnd;
}

static HIMC getContext(HWND wnd)
{
    HIMC imc;
    if (aimm)
        aimm->GetContext(wnd, &imc);
    else
        imc = ImmGetContext(wnd);

    return imc;
}

static void releaseContext(HWND wnd, HIMC imc)
{
    if (aimm)
        aimm->ReleaseContext(wnd, imc);
    else
        ImmReleaseContext(wnd, imc);
}

static void notifyIME(HIMC imc, DWORD dwAction, DWORD dwIndex, DWORD dwValue)
{
    if (!imc)
        return;
    if (aimm)
        aimm->NotifyIME(imc, dwAction, dwIndex, dwValue);
    else
        ImmNotifyIME(imc, dwAction, dwIndex, dwValue);
}

static LONG getCompositionString(HIMC himc, DWORD dwIndex, LPVOID lpbuf, DWORD dBufLen, bool *unicode = 0)
{
    LONG len = 0;
    if (unicode)
        *unicode = true;
    if (aimm)
        aimm->GetCompositionStringW(himc, dwIndex, dBufLen, &len, lpbuf);
    else
    {
        if(QSysInfo::WindowsVersion != QSysInfo::WV_95) {
            len = ImmGetCompositionStringW(himc, dwIndex, lpbuf, dBufLen);
        }
#if !defined(Q_OS_WINCE)
        else {
            len = ImmGetCompositionStringA(himc, dwIndex, lpbuf, dBufLen);
            if (unicode)
                *unicode = false;
        }
#endif
    }
    return len;
}

static int getCursorPosition(HIMC himc)
{
    return getCompositionString(himc, GCS_CURSORPOS, 0, 0);
}

static QString getString(HIMC himc, DWORD dwindex, int *selStart = 0, int *selLength = 0)
{
    static char *buffer = 0;
    static int buflen = 0;

    int len = getCompositionString(himc, dwindex, 0, 0) + 1;
    if (!buffer || len > buflen) {
        delete [] buffer;
        buflen = qMin(len, 256);
        buffer = new char[buflen];
    }

    bool unicode = true;
    len = getCompositionString(himc, dwindex, buffer, buflen, &unicode);

    if (selStart) {
        static char *attrbuffer = 0;
        static int attrbuflen = 0;
        int attrlen = getCompositionString(himc, dwindex, 0, 0) + 1;
        if (!attrbuffer || attrlen> attrbuflen) {
            delete [] attrbuffer;
            attrbuflen = qMin(attrlen, 256);
            attrbuffer = new char[attrbuflen];
        }
        attrlen = getCompositionString(himc, GCS_COMPATTR, attrbuffer, attrbuflen);
        *selStart = attrlen+1;
        *selLength = -1;
        for (int i = 0; i < attrlen; i++) {
            if (attrbuffer[i] & ATTR_TARGET_CONVERTED) {
                *selStart = qMin(*selStart, i);
                *selLength = qMax(*selLength, i);
            }
        }
        *selLength = qMax(0, *selLength - *selStart + 1);
    }

    if (len <= 0)
        return QString();
    if (unicode) {
        return QString((QChar *)buffer, len/sizeof(QChar));
    }
    else {
        buffer[len] = 0;
        WCHAR *wc = new WCHAR[len+1];
        int l = MultiByteToWideChar(CP_ACP, MB_PRECOMPOSED,
            buffer, len, wc, len+1);
        QString res = QString((QChar *)wc, l);
        delete [] wc;
        return res;
    }
}

void QWinInputContext::TranslateMessage(const MSG *msg)
{
    if (!aimmpump || aimmpump->OnTranslateMessage(msg) != S_OK)
        ::TranslateMessage(msg);
}

LRESULT QWinInputContext::DefWindowProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    LRESULT retval;
    if (!aimm || aimm->OnDefWindowProc(hwnd, msg, wParam, lParam, &retval) != S_OK)
    {
        QT_WA({
            retval = ::DefWindowProc(hwnd, msg, wParam, lParam);
        } , {
            retval = ::DefWindowProcA(hwnd,msg, wParam, lParam);
        });
    }
    return retval;
}


void QWinInputContext::update()
{
    QWidget *w = focusWidget();
    if(!w)
        return;

    Q_ASSERT(w->testAttribute(Qt::WA_WState_Created));
    HIMC imc = getContext(w->effectiveWinId());

    if (!imc)
        return;

    QFont f = qvariant_cast<QFont>(w->inputMethodQuery(Qt::ImFont));
    HFONT hf;
    hf = f.handle();

    QT_WA({
        LOGFONT lf;
        if (GetObject(hf, sizeof(lf), &lf))
            if (aimm)
                aimm->SetCompositionFontW(imc, &lf);
            else
                ImmSetCompositionFont(imc, &lf);
    } , {
        LOGFONTA lf;
        if (GetObjectA(hf, sizeof(lf), &lf))
            if (aimm)
                aimm->SetCompositionFontA(imc, &lf);
            else
                ImmSetCompositionFontA(imc, &lf);
    });

    QRect r = w->inputMethodQuery(Qt::ImMicroFocus).toRect();

    // The ime window positions are based on the WinId with active focus.
    QWidget *imeWnd = QWidget::find(::GetFocus());
    if (imeWnd && !aimm) {
        QPoint pt (r.topLeft());
        pt = w->mapToGlobal(pt);
        pt = imeWnd->mapFromGlobal(pt);
        r.moveTo(pt);
    }

    COMPOSITIONFORM cf;
    // ### need X-like inputStyle config settings
    cf.dwStyle = CFS_FORCE_POSITION;
    cf.ptCurrentPos.x = r.x();
    cf.ptCurrentPos.y = r.y();

    CANDIDATEFORM candf;
    candf.dwIndex = 0;
    candf.dwStyle = CFS_EXCLUDE;
    candf.ptCurrentPos.x = r.x();
    candf.ptCurrentPos.y = r.y() + r.height();
    candf.rcArea.left = r.x();
    candf.rcArea.top = r.y();
    candf.rcArea.right = r.x() + r.width();
    candf.rcArea.bottom = r.y() + r.height();

    if(haveCaret)
        SetCaretPos(r.x(), r.y());

    if (aimm) {
        aimm->SetCompositionWindow(imc, &cf);
        aimm->SetCandidateWindow(imc, &candf);
    } else {
        ImmSetCompositionWindow(imc, &cf);
        ImmSetCandidateWindow(imc, &candf);
    }

    releaseContext(w->effectiveWinId(), imc);
}


bool QWinInputContext::endComposition()
{
    QWidget *fw = focusWidget();
#ifdef Q_IME_DEBUG
    qDebug("endComposition! fw = %s", fw ? fw->className() : "(null)");
#endif
    bool result = true;
    if(imePosition == -1 || recursionGuard)
        return result;

    // Googles Pinyin Input Method likes to call endComposition again
    // when we call notifyIME with CPS_CANCEL, so protect ourselves
    // against that.
    recursionGuard = true;

    if (fw) {
        Q_ASSERT(fw->testAttribute(Qt::WA_WState_Created));
        HIMC imc = getContext(fw->effectiveWinId());
        notifyIME(imc, NI_COMPOSITIONSTR, CPS_CANCEL, 0);
        releaseContext(fw->effectiveWinId(), imc);
        if(haveCaret) {
            DestroyCaret();
            haveCaret = false;
        }
    }

    if (!fw)
        fw = qApp->focusWidget();

    if (fw) {
        QInputMethodEvent e;
        result = qt_sendSpontaneousEvent(fw, &e);
    }

    if (imeComposition)
        imeComposition->clear();
    imePosition = -1;

    recursionGuard = false;

    return result;
}

void QWinInputContext::reset()
{
    QWidget *fw = focusWidget();

#ifdef Q_IME_DEBUG
    qDebug("sending accept to focus widget %s", fw ? fw->className() : "(null)");
#endif

    if (fw && imePosition != -1) {
        QInputMethodEvent e;
        if (imeComposition)
            e.setCommitString(*imeComposition);
         imePosition = -1;
         qt_sendSpontaneousEvent(fw, &e);
    }

    if (imeComposition)
        imeComposition->clear();
    imePosition = -1;

    if (fw) {
        Q_ASSERT(fw->testAttribute(Qt::WA_WState_Created));
        HIMC imc = getContext(fw->effectiveWinId());
        notifyIME(imc, NI_COMPOSITIONSTR, CPS_CANCEL, 0);
        releaseContext(fw->effectiveWinId(), imc);
    }

}


bool QWinInputContext::startComposition()
{
#ifdef Q_IME_DEBUG
    qDebug("startComposition");
#endif

    if (!imeComposition)
        imeComposition = new QString();

    QWidget *fw = focusWidget();
    if (fw) {
        Q_ASSERT(fw->testAttribute(Qt::WA_WState_Created));
        imePosition = 0;
        haveCaret = CreateCaret(fw->effectiveWinId(), 0, 1, 1);
        HideCaret(fw->effectiveWinId());
        update();
    }
    return fw != 0;
}

enum StandardFormat {
    PreeditFormat,
    SelectionFormat
};

bool QWinInputContext::composition(LPARAM lParam)
{
#ifdef Q_IME_DEBUG
    QString str;
    if (lParam & GCS_RESULTSTR)
        str += "RESULTSTR ";
    if (lParam & GCS_COMPSTR)
        str += "COMPSTR ";
    if (lParam & GCS_COMPATTR)
        str += "COMPATTR ";
    if (lParam & GCS_CURSORPOS)
        str += "CURSORPOS ";
    if (lParam & GCS_COMPCLAUSE)
        str += "COMPCLAUSE ";
    if (lParam & CS_INSERTCHAR)
       str += "INSERTCHAR ";
    if (lParam & CS_NOMOVECARET)
       str += "NOMOVECARET ";
    qDebug("composition, lParam=(%x) %s imePosition=%d", lParam, str.latin1(), imePosition);
#endif

    bool result = true;

    if(!lParam)
        // bogus event
        return true;

    QWidget *fw = qApp->focusWidget();
    if (fw) {
        Q_ASSERT(fw->testAttribute(Qt::WA_WState_Created));
        HIMC imc = getContext(fw->effectiveWinId());
        QInputMethodEvent e;
        if (lParam & (GCS_COMPSTR | GCS_COMPATTR | GCS_CURSORPOS)) {
            if (imePosition == -1)
                // need to send a start event
                startComposition();

            // some intermediate composition result
            int selStart, selLength;
            *imeComposition = getString(imc, GCS_COMPSTR, &selStart, &selLength);
            imePosition = getCursorPosition(imc);
            if (lParam & CS_INSERTCHAR  && lParam & CS_NOMOVECARET) {
                // make korean work correctly. Hope this is correct for all IMEs
                selStart = 0;
                selLength = imeComposition->length();
            }
    	    if(selLength == 0)
                selStart = 0;

           QList<QInputMethodEvent::Attribute> attrs;
           if (selStart > 0)
               attrs << QInputMethodEvent::Attribute(QInputMethodEvent::TextFormat, 0, selStart,
                                            standardFormat(PreeditFormat));
           if (selLength)
               attrs << QInputMethodEvent::Attribute(QInputMethodEvent::TextFormat, selStart, selLength,
                                            standardFormat(SelectionFormat));
           if (selStart + selLength < imeComposition->length())
               attrs << QInputMethodEvent::Attribute(QInputMethodEvent::TextFormat, selStart + selLength,
                                            imeComposition->length() - selStart - selLength,
                                            standardFormat(PreeditFormat));
           if(imePosition >= 0)
               attrs << QInputMethodEvent::Attribute(QInputMethodEvent::Cursor, imePosition, selLength ? 0 : 1, QVariant());

           e = QInputMethodEvent(*imeComposition, attrs);
        }
        if (lParam & GCS_RESULTSTR) {
            if(imePosition == -1)
                startComposition();
            // a fixed result, return the converted string
            *imeComposition = getString(imc, GCS_RESULTSTR);
            imePosition = -1;
            e.setCommitString(*imeComposition);
            imeComposition->clear();
        }
        result = qt_sendSpontaneousEvent(fw, &e);
        update();
        releaseContext(fw->effectiveWinId(), imc);
    }
#ifdef Q_IME_DEBUG
    qDebug("imecomposition: cursor pos at %d, str=%x", imePosition, str[0].unicode());
#endif
    return result;
}

static HIMC defaultContext = 0;

// checks whether widget is a popup
inline bool isPopup(QWidget *w)
{
    if (w && (w->windowFlags() & Qt::Popup) == Qt::Popup)
        return true;
    else 
        return false;
}
// checks whether widget is in a popup
inline bool isInPopup(QWidget *w)
{
    if (w && (isPopup(w) ||  isPopup(w->window())))
        return true;
    else 
        return false;
}

// find the parent widget, which is a non popup toplevel
// this is valid only if the widget is/in a popup
inline QWidget *findParentforPopup(QWidget *w)
{
    QWidget *e = QWidget::find(w->effectiveWinId());
    // check if this or its parent is a popup
    while (isInPopup(e)) {
        e = e->window()->parentWidget();
        if (!e) 
            break;
        e = QWidget::find(e->effectiveWinId());
    }
    if (e)
        return e->window();
    else
        return 0;
}

// enables or disables the ime 
inline void enableIme(QWidget *w,  bool value) 
{
    if (value) {
        // enable ime
        if (defaultContext)
            ImmAssociateContext(w->effectiveWinId(), defaultContext);
#ifdef Q_OS_WINCE
        if (qApp->autoSipEnabled())
            qt_wince_show_SIP(true);
#endif
    } else {
        // disable ime
        HIMC oldimc = ImmAssociateContext(w->effectiveWinId(), 0);
        if (!defaultContext)
            defaultContext = oldimc;
#ifdef Q_OS_WINCE
        if (qApp->autoSipEnabled())
            qt_wince_show_SIP(false);
#endif
    }
}


void QInputContextPrivate::updateImeStatus(QWidget *w, bool hasFocus)
{
    if (!w)
        return;
    bool e = w->testAttribute(Qt::WA_InputMethodEnabled) && w->isEnabled();
    bool hasIme = e && hasFocus;
#ifdef Q_IME_DEBUG
    qDebug("%s HasFocus = %d hasIme = %d e = %d ", w->className(), hasFocus, hasIme, e);
#endif
    if (hasFocus || e) {
        if (isInPopup(w))
            QWinInputContext::enablePopupChild(w, hasIme);
        else
            QWinInputContext::enable(w, hasIme);
    }
}

void QWinInputContext::enablePopupChild(QWidget *w, bool e)
{
    if (aimm) {
        enable(w, e);
        return;
    }

    if (!w || !isInPopup(w))
        return;
#ifdef Q_IME_DEBUG
    qDebug("enablePopupChild: w=%s, enable = %s", w ? w->className() : "(null)" , e ? "true" : "false");
#endif
    QWidget *parent = findParentforPopup(w);
    if (parent) {
        // update ime status of the normal toplevel parent of the popup
        enableIme(parent, e);
    }
    QWidget *toplevel = w->window();
    if (toplevel) {
        // update ime status of the toplevel popup
        enableIme(toplevel, e);
    }
}

void QWinInputContext::enable(QWidget *w, bool e)
{
    if(w) {
#ifdef Q_IME_DEBUG
        qDebug("enable: w=%s, enable = %s", w ? w->className() : "(null)" , e ? "true" : "false");
#endif
        if (!w->testAttribute(Qt::WA_WState_Created))
            return;
        if(aimm) {
            HIMC oldimc;
            if (!e) {
                aimm->AssociateContext(w->effectiveWinId(), 0, &oldimc);
                if (!defaultContext)
                    defaultContext = oldimc;
            } else if (defaultContext) {
                aimm->AssociateContext(w->effectiveWinId(), defaultContext, &oldimc);
            }
        } else {
            // update ime status on the widget
            QWidget *p = QWidget::find(w->effectiveWinId());
            if (p)
                enableIme(p, e);
        }
    }
}

void QWinInputContext::setFocusWidget(QWidget *w)
{
    QInputContext::setFocusWidget(w);
    update();
}

bool QWinInputContext::isComposing() const
{
    return imeComposition && !imeComposition->isEmpty();
}

void QWinInputContext::mouseHandler(int pos, QMouseEvent *e)
{
    if(e->type() != QEvent::MouseButtonPress)
        return;

    if (pos < 0 || pos > imeComposition->length())
        reset();

    // Probably should pass the correct button, but it seems to work fine like this.
    DWORD button = MK_LBUTTON;

    QWidget *fw = focusWidget();
    if (fw) {
        Q_ASSERT(fw->testAttribute(Qt::WA_WState_Created));
        HIMC himc = getContext(fw->effectiveWinId());
        HWND ime_wnd = getDefaultIMEWnd(fw->effectiveWinId());
        SendMessage(ime_wnd, WM_MSIME_MOUSE, MAKELONG(MAKEWORD(button, pos == 0 ? 2 : 1), pos), (LPARAM)himc);
        releaseContext(fw->effectiveWinId(), himc);
    }
    //qDebug("mouseHandler: got value %d pos=%d", ret,pos);
}

QString QWinInputContext::language()
{
    return QString();
}

QT_END_NAMESPACE