/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */

/*

 * This file is part of the LibreOffice project.

 *

 * This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/.

 *

 * This file incorporates work covered by the following license notice:

 *

 *   Licensed to the Apache Software Foundation (ASF) under one or more

 *   contributor license agreements. See the NOTICE file distributed

 *   with this work for additional information regarding copyright

 *   ownership. The ASF licenses this file to you under the Apache

 *   License, Version 2.0 (the "License"); you may not use this file

 *   except in compliance with the License. You may obtain a copy of

 *   the License at http://www.apache.org/licenses/LICENSE-2.0 .

 */

#include <com/sun/star/uno/Reference.h>

#include <com/sun/star/linguistic2/SpellFailure.hpp>

#include <com/sun/star/linguistic2/XLinguProperties.hpp>

#include <comphelper/lok.hxx>

#include <comphelper/processfactory.hxx>

#include <cppuhelper/supportsservice.hxx>

#include <cppuhelper/weak.hxx>

#include <com/sun/star/lang/XMultiServiceFactory.hpp>

#include <tools/debug.hxx>

#include <osl/mutex.hxx>

#include <osl/thread.h>

#include <com/sun/star/ucb/XSimpleFileAccess.hpp>

#include <lingutil.hxx>

#include <hunspell.hxx>

#include "sspellimp.hxx"

#include <linguistic/misc.hxx>

#include <linguistic/spelldta.hxx>

#include <i18nlangtag/languagetag.hxx>

#include <svtools/strings.hrc>

#include <unotools/lingucfg.hxx>

#include <unotools/resmgr.hxx>

#include <osl/diagnose.h>

#include <osl/file.hxx>

#include <rtl/ustrbuf.hxx>

#include <rtl/textenc.h>

#include <sal/log.hxx>

#include <numeric>

#include <utility>

#include <vector>

#include <set>

#include <string.h>

using namespace osl;

using namespace com::sun::star;

using namespace com::sun::star::beans;

using namespace com::sun::star::lang;

using namespace com::sun::star::uno;

using namespace com::sun::star::linguistic2;

using namespace linguistic;

// XML-header of SPELLML queries

#if !defined SPELL_XML

constexpr OUStringLiteral SPELL_XML = u"<?xml?>";

#endif

// only available in hunspell >= 1.5

#if !defined MAXWORDLEN

#define MAXWORDLEN 176

#endif

SpellChecker::SpellChecker() :

    m_aEvtListeners(GetLinguMutex()),

    m_bDisposing(false)

{

}

SpellChecker::DictItem::DictItem(OUString i_DName, Locale i_DLoc, rtl_TextEncoding i_DEnc)

    : m_aDName(std::move(i_DName))

    , m_aDLoc(std::move(i_DLoc))

    , m_aDEnc(i_DEnc)

{

}

SpellChecker::~SpellChecker()

{

    if (m_pPropHelper)

    {

        m_pPropHelper->RemoveAsPropListener();

    }

}

PropertyHelper_Spelling & SpellChecker::GetPropHelper_Impl()

{

    if (!m_pPropHelper)

    {

        Reference< XLinguProperties >   xPropSet = GetLinguProperties();

        m_pPropHelper.reset( new PropertyHelper_Spelling( static_cast<XSpellChecker *>(this), xPropSet ) );

        m_pPropHelper->AddAsPropListener();   //! after a reference is established

    }

    return *m_pPropHelper;

}

Sequence< Locale > SAL_CALL SpellChecker::getLocales()

{

    MutexGuard  aGuard( GetLinguMutex() );

    // this routine should return the locales supported by the installed

    // dictionaries.

    if (m_DictItems.empty())

    {

        SvtLinguConfig aLinguCfg;

        // get list of extension dictionaries-to-use

        // (or better speaking: the list of dictionaries using the

        // new configuration entries).

        std::vector< SvtLinguConfigDictionaryEntry > aDics;

        uno::Sequence< OUString > aFormatList;

        aLinguCfg.GetSupportedDictionaryFormatsFor( u"SpellCheckers"_ustr,

                u"org.openoffice.lingu.MySpellSpellChecker"_ustr, aFormatList );

        for (auto const& format : aFormatList)

        {

            std::vector< SvtLinguConfigDictionaryEntry > aTmpDic(

                    aLinguCfg.GetActiveDictionariesByFormat(format) );

            aDics.insert( aDics.end(), aTmpDic.begin(), aTmpDic.end() );

        }

        //!! for compatibility with old dictionaries (the ones not using extensions

        //!! or new configuration entries, but still using the dictionary.lst file)

        //!! Get the list of old style spell checking dictionaries to use...

        std::vector< SvtLinguConfigDictionaryEntry > aOldStyleDics(

                GetOldStyleDics( "DICT" ) );

        // to prefer dictionaries with configuration entries we will only

        // use those old style dictionaries that add a language that

        // is not yet supported by the list of new style dictionaries

        MergeNewStyleDicsAndOldStyleDics( aDics, aOldStyleDics );

        if (!aDics.empty())

        {

            uno::Reference< lang::XMultiServiceFactory > xServiceFactory(comphelper::getProcessServiceFactory());

            uno::Reference< ucb::XSimpleFileAccess > xAccess(xServiceFactory->createInstance(u"com.sun.star.ucb.SimpleFileAccess"_ustr), uno::UNO_QUERY);

            // get supported locales from the dictionaries-to-use...

            std::set<OUString> aLocaleNamesSet;

            for (auto const& dict : aDics)

            {

                const uno::Sequence< OUString > aLocaleNames( dict.aLocaleNames );

                uno::Sequence< OUString > aLocations( dict.aLocations );

                SAL_WARN_IF(

                    aLocaleNames.hasElements() && !aLocations.hasElements(),

                    "lingucomponent", "no locations");

                if (aLocations.hasElements())

                {

                    if (xAccess.is() && xAccess->exists(aLocations[0]))

                    {

                        for (auto const& locale : aLocaleNames)

                        {

                            if (!comphelper::LibreOfficeKit::isAllowlistedLanguage(locale))

                                continue;

                            aLocaleNamesSet.insert(locale);

                        }

                    }

                    else

                    {

                        SAL_WARN(

                            "lingucomponent",

                            "missing <" << aLocations[0] << ">");

                    }

                }

            }

            // ... and add them to the resulting sequence

            m_aSuppLocales.realloc( aLocaleNamesSet.size() );

            std::transform(

                aLocaleNamesSet.begin(), aLocaleNamesSet.end(), m_aSuppLocales.getArray(),

                [](auto const& localeName) { return LanguageTag::convertToLocale(localeName); });

            //! For each dictionary and each locale we need a separate entry.

            //! If this results in more than one dictionary per locale than (for now)

            //! it is undefined which dictionary gets used.

            //! In the future the implementation should support using several dictionaries

            //! for one locale.

            sal_uInt32 nDictSize = std::accumulate(aDics.begin(), aDics.end(), sal_uInt32(0),

                [](const sal_uInt32 nSum, const SvtLinguConfigDictionaryEntry& dict) {

                    return nSum + dict.aLocaleNames.getLength(); });

            // add dictionary information

            m_DictItems.reserve(nDictSize);

            for (auto const& dict : aDics)

            {

                if (dict.aLocaleNames.hasElements() &&

                    dict.aLocations.hasElements())

                {

                    const uno::Sequence< OUString > aLocaleNames( dict.aLocaleNames );

                    // currently only one language per dictionary is supported in the actual implementation...

                    // Thus here we work-around this by adding the same dictionary several times.

                    // Once for each of its supported locales.

                    for (auto const& localeName : aLocaleNames)

                    {

                        // also both files have to be in the same directory and the

                        // file names must only differ in the extension (.aff/.dic).

                        // Thus we use the first location only and strip the extension part.

                        OUString aLocation = dict.aLocations[0];

                        sal_Int32 nPos = aLocation.lastIndexOf( '.' );

                        aLocation = aLocation.copy( 0, nPos );

                        m_DictItems.emplace_back(aLocation, LanguageTag::convertToLocale(localeName), RTL_TEXTENCODING_DONTKNOW);

                    }

                }

            }

            DBG_ASSERT( nDictSize == m_DictItems.size(), "index mismatch?" );

        }

        else

        {

            // no dictionary found so register no dictionaries

            m_aSuppLocales.realloc(0);

        }

    }

    return m_aSuppLocales;

}

sal_Bool SAL_CALL SpellChecker::hasLocale(const Locale& rLocale)

{

    MutexGuard  aGuard( GetLinguMutex() );

    bool bRes = false;

    if (!m_aSuppLocales.hasElements())

        getLocales();

    for (auto const& suppLocale : m_aSuppLocales)

    {

        if (rLocale == suppLocale)

        {

            bRes = true;

            break;

        }

    }

    return bRes;

}

#define SPELL_NON_ASCII_APOSTROPHE 1 << 10

sal_Int16 SpellChecker::GetSpellFailure(const OUString &rWord, const Locale &rLocale, int& rInfo)

{

    if (rWord.getLength() > MAXWORDLEN)

        return -1;

    Hunspell * pMS = nullptr;

    rtl_TextEncoding eEnc = RTL_TEXTENCODING_DONTKNOW;

    // initialize a myspell object for each dictionary once

    // (note: mutex is held higher up in isValid)

    sal_Int16 nRes = -1;

    // first handle smart quotes both single and double

    OUStringBuffer rBuf(rWord);

    sal_Int32 n = rBuf.getLength();

    sal_Unicode c;

    sal_Int32 extrachar = 0;

    const bool bDoNotConvertApostrophe = bool(rInfo & SPELL_NON_ASCII_APOSTROPHE);

    bool bHasNonASCIIApostrophe = false;

    rInfo = 0;

    for (sal_Int32 ix=0; ix < n; ix++)

    {

        c = rBuf[ix];

        if ((c == 0x201C) || (c == 0x201D))

            rBuf[ix] = u'"';

        else if (!bDoNotConvertApostrophe && ((c == 0x2018) || (c == 0x2019)))

        {

            rBuf[ix] = u'\'';

            bHasNonASCIIApostrophe = true;

        }

        // recognize words with Unicode ligatures and ZWNJ/ZWJ characters (only

        // with 8-bit encoded dictionaries. For UTF-8 encoded dictionaries

        // set ICONV and IGNORE aff file options, if needed.)

        else if ((c == 0x200C) || (c == 0x200D) ||

            ((c >= 0xFB00) && (c <= 0xFB04)))

                extrachar = 1;

    }

    OUString nWord(rBuf.makeStringAndClear());

    if (n)

    {

        for (auto& currDict : m_DictItems)

        {

            pMS = nullptr;

            eEnc = RTL_TEXTENCODING_DONTKNOW;

            if (rLocale == currDict.m_aDLoc)

            {

                if (!currDict.m_pDict)

                {

                    OUString dicpath = currDict.m_aDName + ".dic";

                    OUString affpath = currDict.m_aDName + ".aff";

                    OUString dict;

                    OUString aff;

                    osl::FileBase::getSystemPathFromFileURL(dicpath,dict);

                    osl::FileBase::getSystemPathFromFileURL(affpath,aff);

#if defined(_WIN32)

                    // workaround for Windows specific problem that the

                    // path length in calls to 'fopen' is limited to somewhat

                    // about 120+ characters which will usually be exceed when

                    // using dictionaries as extensions. (Hunspell waits UTF-8 encoded

                    // path with \\?\ long path prefix.)

                    OString aTmpaff = Win_AddLongPathPrefix(OUStringToOString(aff, RTL_TEXTENCODING_UTF8));

                    OString aTmpdict = Win_AddLongPathPrefix(OUStringToOString(dict, RTL_TEXTENCODING_UTF8));

#else

                    OString aTmpaff(OU2ENC(aff,osl_getThreadTextEncoding()));

                    OString aTmpdict(OU2ENC(dict,osl_getThreadTextEncoding()));

#endif

                    currDict.m_pDict = std::make_unique<Hunspell>(aTmpaff.getStr(),aTmpdict.getStr());

#if defined(H_DEPRECATED)

                    currDict.m_aDEnc = getTextEncodingFromCharset(currDict.m_pDict->get_dict_encoding().c_str());

#else

                    currDict.m_aDEnc = getTextEncodingFromCharset(currDict.m_pDict->get_dic_encoding());

#endif

                }

                pMS  = currDict.m_pDict.get();

                eEnc = currDict.m_aDEnc;

            }

            if (pMS)

            {

                // we don't want to work with a default text encoding since following incorrect

                // results may occur only for specific text and thus may be hard to notice.

                // Thus better always make a clean exit here if the text encoding is in question.

                // Hopefully something not working at all will raise proper attention quickly. ;-)

                DBG_ASSERT( eEnc != RTL_TEXTENCODING_DONTKNOW, "failed to get text encoding! (maybe incorrect encoding string in file)" );

                if (eEnc == RTL_TEXTENCODING_DONTKNOW)

                    return -1;

                OString aWrd(OU2ENC(nWord,eEnc));

#if defined(H_DEPRECATED)

                bool bVal = pMS->spell(std::string(aWrd), &rInfo);

#else

                bool bVal = pMS->spell(aWrd.getStr(), &rInfo) != 0;

#endif

                if (!bVal) {

                    if (extrachar && (eEnc != RTL_TEXTENCODING_UTF8)) {

                        OUStringBuffer aBuf(nWord);

                        n = aBuf.getLength();

                        for (sal_Int32 ix=n-1; ix >= 0; ix--)

                        {

                          switch (aBuf[ix]) {

                            case 0xFB00: aBuf.remove(ix, 1); aBuf.insert(ix, "ff"); break;

                            case 0xFB01: aBuf.remove(ix, 1); aBuf.insert(ix, "fi"); break;

                            case 0xFB02: aBuf.remove(ix, 1); aBuf.insert(ix, "fl"); break;

                            case 0xFB03: aBuf.remove(ix, 1); aBuf.insert(ix, "ffi"); break;

                            case 0xFB04: aBuf.remove(ix, 1); aBuf.insert(ix, "ffl"); break;

                            case 0x200C:

                            case 0x200D: aBuf.remove(ix, 1); break;

                          }

                        }

                        OUString aWord(aBuf.makeStringAndClear());

                        OString bWrd(OU2ENC(aWord, eEnc));

#if defined(H_DEPRECATED)

                        bVal = pMS->spell(std::string(bWrd), &rInfo);

#else

                        bVal = pMS->spell(bWrd.getStr(), &rInfo) != 0;

#endif

                        if (bVal) return -1;

                    }

                    nRes = SpellFailure::SPELLING_ERROR;

                } else {

                    return -1;

                }

                pMS = nullptr;

            }

        }

    }

    // checked with apostrophe conversion

    if ( bHasNonASCIIApostrophe )

        rInfo |= SPELL_NON_ASCII_APOSTROPHE;

    return nRes;

}

sal_Bool SAL_CALL SpellChecker::isValid( const OUString& rWord, const Locale& rLocale,

            const css::uno::Sequence< css::beans::PropertyValue >& rProperties )

{

    MutexGuard  aGuard( GetLinguMutex() );

    if (rLocale == Locale()  ||  rWord.isEmpty())

        return true;

    if (!hasLocale( rLocale ))

        return true;

    // return sal_False to process SPELLML requests (they are longer than the header)

    if (rWord.match(SPELL_XML, 0) && (rWord.getLength() > 10)) return false;

    // Get property values to be used.

    // These are be the default values set in the SN_LINGU_PROPERTIES

    // PropertySet which are overridden by the supplied ones from the

    // last argument.

    // You'll probably like to use a simpler solution than the provided

    // one using the PropertyHelper_Spell.

    PropertyHelper_Spelling& rHelper = GetPropHelper();

    rHelper.SetTmpPropVals( rProperties );

    int nInfo = 0; // return compound information, disable apostrophe conversion

    sal_Int16 nFailure = GetSpellFailure( rWord, rLocale, nInfo );

    // it contains non-ASCII apostrophe, and it was bad with ASCII conversion:

    // check the word with the original apostrophe character(s), too

    if ( nFailure != -1 && nInfo & SPELL_NON_ASCII_APOSTROPHE ) {

        nInfo = SPELL_NON_ASCII_APOSTROPHE; // disable apostrophe conversion

        nFailure = GetSpellFailure( rWord, rLocale, nInfo );

    }

    if (nFailure != -1 && !rWord.match(SPELL_XML, 0))

    {

        LanguageType nLang = LinguLocaleToLanguage( rLocale );

        // postprocess result for errors that should be ignored

        const bool bIgnoreError =

                (!rHelper.IsSpellUpperCase()  && IsUpper( rWord, nLang )) ||

                (!rHelper.IsSpellWithDigits() && HasDigits( rWord ));

        if (bIgnoreError)

            nFailure = -1;

    }

//#define SPELL_COMPOUND 1 << 0

    // valid word, but it's a rule-based compound word

    if ( nFailure == -1 && (nInfo & SPELL_COMPOUND) )

    {

        bool bHasHyphen = rWord.indexOf('-') > -1;

        if ( (bHasHyphen && !rHelper.IsSpellHyphenatedCompound()) ||

             (!bHasHyphen && !rHelper.IsSpellClosedCompound()) )

        {

            return false;

        }

    }

    return (nFailure == -1);

}

Reference< XSpellAlternatives >

    SpellChecker::GetProposals( const OUString &rWord, const Locale &rLocale )

{

    // Retrieves the return values for the 'spell' function call in case

    // of a misspelled word.

    // Especially it may give a list of suggested (correct) words:

    Reference< XSpellAlternatives > xRes;

    // note: mutex is held by higher up by spell which covers both

    Hunspell* pMS = nullptr;

    rtl_TextEncoding eEnc = RTL_TEXTENCODING_DONTKNOW;

    // first handle smart quotes (single and double)

    OUStringBuffer rBuf(rWord);

    sal_Int32 n = rBuf.getLength();

    sal_Unicode c;

    for (sal_Int32 ix=0; ix < n; ix++)

    {

        c = rBuf[ix];

        if ((c == 0x201C) || (c == 0x201D))

            rBuf[ix] = u'"';

        if ((c == 0x2018) || (c == 0x2019))

            rBuf[ix] = u'\'';

    }

    OUString nWord(rBuf.makeStringAndClear());

    if (n)

    {

        LanguageType nLang = LinguLocaleToLanguage( rLocale );

        int numsug = 0;

        Sequence< OUString > aStr( 0 );

        for (const auto& currDict : m_DictItems)

        {

            pMS = nullptr;

            eEnc = RTL_TEXTENCODING_DONTKNOW;

            if (rLocale == currDict.m_aDLoc)

            {

                pMS  = currDict.m_pDict.get();

                eEnc = currDict.m_aDEnc;

            }

            if (pMS)

            {

                OString aWrd(OU2ENC(nWord,eEnc));

#if defined(H_DEPRECATED)

                std::vector<std::string> suglst = pMS->suggest(std::string(aWrd));

                if (!suglst.empty())

                {

                    aStr.realloc(numsug + suglst.size());

                    OUString *pStr = aStr.getArray();

                    for (size_t ii = 0; ii < suglst.size(); ++ii)

                    {

                        pStr[numsug + ii] = OUString(suglst[ii].c_str(), suglst[ii].size(), eEnc);

                    }

                    numsug += suglst.size();

                }

#else

                char ** suglst = nullptr;

                int count = pMS->suggest(&suglst, aWrd.getStr());

                if (count)

                {

                    aStr.realloc( numsug + count );

                    OUString *pStr = aStr.getArray();

                    for (int ii=0; ii < count; ++ii)

                    {

                        OUString cvtwrd(suglst[ii],strlen(suglst[ii]),eEnc);

                        pStr[numsug + ii] = cvtwrd;

                    }

                    numsug += count;

                }

                pMS->free_list(&suglst, count);

#endif

            }

        }

        // now return an empty alternative for no suggestions or the list of alternatives if some found

        xRes = SpellAlternatives::CreateSpellAlternatives( rWord, nLang, SpellFailure::SPELLING_ERROR, aStr );

        return xRes;

    }

    return xRes;

}

Reference< XSpellAlternatives > SAL_CALL SpellChecker::spell(

        const OUString& rWord, const Locale& rLocale,

        const css::uno::Sequence< css::beans::PropertyValue >& rProperties )

{

    MutexGuard  aGuard( GetLinguMutex() );

    if (rLocale == Locale()  ||  rWord.isEmpty())

        return nullptr;

    if (!hasLocale( rLocale ))

        return nullptr;

    Reference< XSpellAlternatives > xAlt;

    if (!isValid( rWord, rLocale, rProperties ))

    {

        xAlt =  GetProposals( rWord, rLocale );

    }

    return xAlt;

}

sal_Bool SAL_CALL SpellChecker::addLinguServiceEventListener(

        const Reference< XLinguServiceEventListener >& rxLstnr )

{

    MutexGuard  aGuard( GetLinguMutex() );

    bool bRes = false;

    if (!m_bDisposing && rxLstnr.is())

    {

        bRes = GetPropHelper().addLinguServiceEventListener( rxLstnr );

    }

    return bRes;

}

sal_Bool SAL_CALL SpellChecker::removeLinguServiceEventListener(

        const Reference< XLinguServiceEventListener >& rxLstnr )

{

    MutexGuard  aGuard( GetLinguMutex() );

    bool bRes = false;

    if (!m_bDisposing && rxLstnr.is())

    {

        bRes = GetPropHelper().removeLinguServiceEventListener( rxLstnr );

    }

    return bRes;

}

OUString SAL_CALL SpellChecker::getServiceDisplayName(const Locale& rLocale)

{

    std::locale loc(Translate::Create("svt", LanguageTag(rLocale)));

    return Translate::get(STR_DESCRIPTION_HUNSPELL, loc);

}

void SAL_CALL SpellChecker::initialize( const Sequence< Any >& rArguments )

{

    MutexGuard  aGuard( GetLinguMutex() );

    if (m_pPropHelper)

        return;

    sal_Int32 nLen = rArguments.getLength();

    if (2 == nLen)

    {

        Reference< XLinguProperties >   xPropSet;

        rArguments.getConstArray()[0] >>= xPropSet;

        // rArguments.getConstArray()[1] >>= xDicList;

        //! Pointer allows for access of the non-UNO functions.

        //! And the reference to the UNO-functions while increasing

        //! the ref-count and will implicitly free the memory

        //! when the object is no longer used.

        m_pPropHelper.reset( new PropertyHelper_Spelling( static_cast<XSpellChecker *>(this), xPropSet ) );

        m_pPropHelper->AddAsPropListener();   //! after a reference is established

    }

    else {

        OSL_FAIL( "wrong number of arguments in sequence" );

    }

}

void SAL_CALL SpellChecker::dispose()

{

    MutexGuard  aGuard( GetLinguMutex() );

    if (!m_bDisposing)

    {

        m_bDisposing = true;

        EventObject aEvtObj( static_cast<XSpellChecker *>(this) );

        m_aEvtListeners.disposeAndClear( aEvtObj );

        if (m_pPropHelper)

        {

            m_pPropHelper->RemoveAsPropListener();

            m_pPropHelper.reset();

        }

    }

}

void SAL_CALL SpellChecker::addEventListener( const Reference< XEventListener >& rxListener )

{

    MutexGuard  aGuard( GetLinguMutex() );

    if (!m_bDisposing && rxListener.is())

        m_aEvtListeners.addInterface( rxListener );

}

void SAL_CALL SpellChecker::removeEventListener( const Reference< XEventListener >& rxListener )

{

    MutexGuard  aGuard( GetLinguMutex() );

    if (!m_bDisposing && rxListener.is())

        m_aEvtListeners.removeInterface( rxListener );

}

// Service specific part

OUString SAL_CALL SpellChecker::getImplementationName()

{

    return u"org.openoffice.lingu.MySpellSpellChecker"_ustr;

}

sal_Bool SAL_CALL SpellChecker::supportsService( const OUString& ServiceName )

{

    return cppu::supportsService(this, ServiceName);

}

Sequence< OUString > SAL_CALL SpellChecker::getSupportedServiceNames()

{

    return { SN_SPELLCHECKER };

}

extern "C" SAL_DLLPUBLIC_EXPORT css::uno::XInterface*

lingucomponent_SpellChecker_get_implementation(

    css::uno::XComponentContext* , css::uno::Sequence<css::uno::Any> const&)

{

    return cppu::acquire(new SpellChecker());

}

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