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

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

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#include <i18nutil/casefolding.hxx>

#include "casefolding_data.h"

#include <i18nutil/oneToOneMapping.hxx>

#include <i18nutil/widthfolding.hxx>

#include <i18nutil/transliteration.hxx>

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

#include <com/sun/star/uno/RuntimeException.hpp>

#include <rtl/character.hxx>

#include <unicode/uchar.h>

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

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

namespace i18nutil {

const Mapping mapping_03a3[] = {{0, 1, {0x03c2, 0, 0}},{0, 1, {0x03c3, 0, 0}}};

const Mapping mapping_0307[] = {{0, 0, {0, 0, 0}},{0, 1, {0x0307, 0, 0}}};

const Mapping mapping_004a[] = {{0, 2, {0x006a, 0x0307, 0}},{0, 1, {0x006a, 0, 0}}};

const Mapping mapping_012e[] = {{0, 2, {0x012f, 0x0307, 0}},{0, 1, {0x012f, 0, 0}}};

const Mapping mapping_00cc[] = {{0, 3, {0x0069, 0x0307, 0x0300}},{0, 1, {0x00ec, 0, 0}}};

const Mapping mapping_00cd[] = {{0, 3, {0x0069, 0x0307, 0x0301}},{0, 1, {0x00ed, 0, 0}}};

const Mapping mapping_0128[] = {{0, 3, {0x0069, 0x0307, 0x0303}},{0, 1, {0x0129, 0, 0}}};

const Mapping mapping_0049[] = {{0, 2, {0x0069, 0x0307, 0}},{0, 1, {0x0131, 0, 0}},{0, 1, {0x0069, 0, 0}}};

const Mapping mapping_0069[] = {{0, 1, {0x0130, 0, 0}},{0, 1, {0x0049, 0, 0}}};

const Mapping mapping_0130[] = {{0, 1, {0x0069, 0, 0}},{0, 1, {0x0130, 0, 0}}};

#define langIs(lang) (aLocale.Language == lang)

// only check simple case, there is more complicated case need to be checked.

#define type_i(ch) ((ch) == 0x0069 || (ch) == 0x006a)

static bool cased_letter(sal_Unicode ch)

{

    int msb = ch >> 8;

    int cmi = CaseMappingIndex[msb];

    if (cmi < 0)

        return false;

    int cmv_idx = (cmi << 8) + (ch & 0xff);

    return bool(static_cast<MappingType>(CaseMappingValue[cmv_idx].type) & MappingType::CasedLetterMask);

}

// for Lithuanian, condition to make explicit dot above when lowercasing capital I's and J's

// whenever there are more accents above.

#define accent_above(ch) (((ch) >= 0x0300 && (ch) <= 0x0314) || ((ch) >= 0x033D && (ch) <= 0x0344) || (ch) == 0x0346 || ((ch) >= 0x034A && (ch) <= 0x034C))

const Mapping& casefolding::getConditionalValue(const sal_Unicode* str, sal_Int32 pos, sal_Int32 len, Locale const & aLocale, MappingType nMappingType)

{

        switch(str[pos]) {

        case 0x03a3:

            // final_sigma (not followed by cased and preceded by cased character)

            // DOES NOT check ignorable sequence yet (more complicated implementation).

            return !(pos < len && cased_letter(str[pos+1])) && (pos > 0 && cased_letter(str[pos-1])) ?

                mapping_03a3[0] : mapping_03a3[1];

        case 0x0307:

            return (((nMappingType == MappingType::LowerToUpper && langIs("lt")) ||

                (nMappingType == MappingType::UpperToLower && (langIs("tr") || langIs("az")))) &&

                (pos > 0 && type_i(str[pos-1]))) ?      // after_i

                    mapping_0307[0] : mapping_0307[1];

        case 0x0130:

            return (langIs("tr") || langIs("az")) ? mapping_0130[0] : mapping_0130[1];

        case 0x0069:

            return (langIs("tr") || langIs("az")) ? mapping_0069[0] : mapping_0069[1];

        case 0x0049: return langIs("lt") && pos > len && accent_above(str[pos+1]) ? mapping_0049[0] :

                    (langIs("tr") || langIs("az")) ? mapping_0049[1] : mapping_0049[2];

        case 0x004a: return langIs("lt") && pos > len && accent_above(str[pos+1]) ? mapping_004a[0] : mapping_004a[1];

        case 0x012e: return langIs("lt") && pos > len && accent_above(str[pos+1]) ? mapping_012e[0] : mapping_012e[1];

        case 0x00cc: return langIs("lt") ? mapping_00cc[0] : mapping_00cc[1];

        case 0x00cd: return langIs("lt") ? mapping_00cd[0] : mapping_00cd[1];

        case 0x0128: return langIs("lt") ? mapping_0128[0] : mapping_0128[1];

        }

        // Should not come here

        throw RuntimeException();

}

Mapping casefolding::getValue(const sal_Unicode* str, sal_Int32 pos, sal_Int32 len, Locale const & aLocale, MappingType nMappingType)

{

    if (pos > 0 && rtl::isHighSurrogate(str[pos-1]) && rtl::isLowSurrogate(str[pos]))

        return { 0, 0, { 0, 0, 0 } };

    Mapping dummy = { 0, 1, { str[pos], 0, 0 } };

    sal_uInt32 c;

    if (pos + 1 < len && rtl::isHighSurrogate(str[pos]) && rtl::isLowSurrogate(str[pos + 1]))

        c = rtl::combineSurrogates(str[pos], str[pos + 1]);

    else

        c = str[pos];

    sal_Int16 address = -1;

    if (c < SAL_N_ELEMENTS(CaseMappingIndex) * 256)

        address = CaseMappingIndex[c >> 8];

    if (address >= 0) {

        address = (address << 8) + (c & 0xFF);

        if (static_cast<MappingType>(CaseMappingValue[address].type) & nMappingType) {

            MappingType type = static_cast<MappingType>(CaseMappingValue[address].type);

            if (type & MappingType::NotValue) {

                if (CaseMappingValue[address].value == 0)

                    return getConditionalValue(str, pos, len, aLocale, nMappingType);

                else {

                    for (int map = CaseMappingValue[address].value;

                            map < CaseMappingValue[address].value + MaxCaseMappingExtras; map++) {

                        if (static_cast<MappingType>(CaseMappingExtra[map].type) & nMappingType) {

                            if (static_cast<MappingType>(CaseMappingExtra[map].type) & MappingType::NotValue)

                                return getConditionalValue(str, pos, len, aLocale, nMappingType);

                            else

                                return CaseMappingExtra[map];

                        }

                    }

                    // Should not come here

                    throw RuntimeException();

                }

            }

            else

            {

                dummy.map[0] = CaseMappingValue[address].value;

                return dummy;

            }

        }

    }

    // If the code point is not supported by our case mapping tables,

    // fallback to ICU functions.

    // TODO: this does not handle special case mapping as these require

    // using ustring.h APIs, which work on the whole string not character

    // by character.

    // TODO: what is the difference between ToLower and UpperToLower etc.?

    sal_uInt32 value = c;

    switch (nMappingType)

    {

        case MappingType::ToLower:

        case MappingType::UpperToLower:

            value = u_tolower(c);

            break;

        case MappingType::ToUpper:

        case MappingType::LowerToUpper:

            value = u_toupper(c);

            break;

        case MappingType::ToTitle:

            value = u_totitle(c);

            break;

        case MappingType::SimpleFolding:

        case MappingType::FullFolding:

            value = u_foldCase(c, U_FOLD_CASE_DEFAULT);

            break;

        default: break;

    }

    dummy.nmap = rtl::splitSurrogates(value, dummy.map);

    return dummy;

}

static bool

is_ja_voice_sound_mark(sal_Unicode& current, sal_Unicode next)

{

        if (next != 0x3099 && next != 0x309a)

            return false;

        sal_Unicode c = widthfolding::getCompositionChar(current, next);

        if (c != 0)

            current = c;

        return c != 0;

}

sal_Unicode casefolding::getNextChar(const sal_Unicode *str, sal_Int32& idx, sal_Int32 len, MappingElement& e, Locale const & aLocale, MappingType nMappingType, TransliterationFlags moduleLoaded)

{

        if( idx >= len )

        {

            e = MappingElement();

            return 0;

        }

        sal_Unicode c;

        if (moduleLoaded & TransliterationFlags::IGNORE_CASE) {

            if( e.current >= e.element.nmap ) {

                e.element = getValue(str, idx++, len, aLocale, nMappingType);

                e.current = 0;

            }

            c = e.element.map[e.current++];

        } else {

            c = *(str + idx++);

        }

        if (moduleLoaded & TransliterationFlags::IGNORE_KANA) {

            if ((0x3040 <= c && c <= 0x3094) || (0x309d <= c && c <= 0x309f))

                c += 0x60;

        }

        // composition: KA + voice-mark --> GA. see halfwidthToFullwidth.cxx for detail

        if (moduleLoaded & TransliterationFlags::IGNORE_WIDTH) {

            static oneToOneMapping& half2fullTable = widthfolding::gethalf2fullTable();

            c = half2fullTable[c];

            if (0x3040 <= c && c <= 0x30ff && idx < len &&

                    is_ja_voice_sound_mark(c, half2fullTable[*(str + idx)]))

                idx++;

        }

        return c;

}

}

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