/*

* Copyright (c) 2002-2005 Nokia Corporation and/or its subsidiary(-ies). 

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description:         Japanese Find Utilities implementation file.

*

*/

// INCLUDE FILES

#include "FindUtilJapanese.h"

#include <jplangutil.h>

// CONSTANTS

_LIT(KDesWildCard, "*");

const TInt KLitTab('\t');

const TInt KLitSpace(' ');

const TInt KLitHyphen('-');

const TInt KLitQuestion('?');

const TInt KLitWildCard('*');

const TInt KLitFullWidthSpace(0x3000);

const TInt KLitFullWidthHyphen(0x2015);

const TInt KLitFullWidthQuestion(0xff1f);

const TInt KLitFullWidthWildCard(0xff0a);

const TInt KLitStartHiragana(0x3041);

const TInt KLitEndHiragana(0x3096);

const TInt KLitStartKatakana(0x30A1);

const TInt KLitLineFeed(8233);

const TInt KMaxWordLength = 200;

const TUint KFullWidthSpace = 0x3000;

// ============================ MEMBER FUNCTIONS ===============================

// -----------------------------------------------------------------------------

// CFindUtilJapanese::CFindUtilJapanese

// C++ default constructor can NOT contain any code, that

// might leave.

// -----------------------------------------------------------------------------

//

CFindUtilJapanese::CFindUtilJapanese()

    {

    }

// Destructor

CFindUtilJapanese::~CFindUtilJapanese()

    {

    }

// -----------------------------------------------------------------------------

// CFindUtilJapanese::IsFindWordSeparator

// (other items were commented in a header).

// -----------------------------------------------------------------------------

//

TBool CFindUtilJapanese::IsFindWordSeparator(TChar aCh)

    {

    return aCh == KLitSpace || aCh == KLitHyphen || aCh == KLitTab ||

        aCh == KLitFullWidthSpace || aCh == KLitFullWidthHyphen ||

        aCh == KLitLineFeed;

    }

// -----------------------------------------------------------------------------

// CFindUtilJapanese::RemoveWordSeparatorsAndWildChars

// (other items were commented in a header).

// -----------------------------------------------------------------------------

//

void CFindUtilJapanese::RemoveWordSeparatorsAndWildChars( TDes16& aSearchPtr )

    {

    TInt len = aSearchPtr.Length();

    for ( TInt ii(0); ii < len; ii++ )

        {

        if ( IsFindWordSeparator(static_cast<TChar>(aSearchPtr[ii])) || 

            aSearchPtr[ii] == KLitWildCard || aSearchPtr[ii] == KLitQuestion ||

            aSearchPtr[ii] == KLitFullWidthWildCard || 

            aSearchPtr[ii] == KLitFullWidthQuestion)

            {

            aSearchPtr.Delete(ii, 1);

            len--;

            continue;

            }

        }

    }

inline TBool IsFindWordSeparator(TChar aCh)

    {

    return (aCh == ' '|| aCh == '-' || aCh == '\t' || aCh==KFullWidthSpace);

    }

void ReplaceCharacters(TDes &aDes, const TDesC &aChars, TChar aReplacement)

    //

    // Running time O(aDes.Length() * aChars.Length())

    // Does not change length of the string.

    // 

    {

    TInt src = 0;

    TInt srclength = aDes.Length();

    while(src < srclength)

        {

        TChar c = aDes[src];

        if (aChars.LocateF(c) != KErrNotFound)

            aDes[src] = TUint16(aReplacement);

        ++src;

        }

    }

// -----------------------------------------------------------------------------

// CFindUtilJapanese::MyFindC

// (other items were commented in a header).

// This method is called by MatchRefineL().

// -----------------------------------------------------------------------------

//

TInt CFindUtilJapanese::MyFindC(const TDesC &aItemString, const TDesC &aSearchText)

    {

    TBuf<KMaxWordLength> searchText;

    TBuf<KMaxWordLength> itemString;

    searchText.Append(aSearchText);

    // The replacecharacters are to disable regexp matching provided

    // by MatchC().

    _LIT(KQuestion,"?");

    _LIT(KStar,"*");

    ReplaceCharacters(searchText, KQuestion, TChar('\t'));

    ReplaceCharacters(searchText, KStar, TChar('\r'));

    searchText.Append(KStar);

    if (aItemString.Length() < KMaxWordLength)

        {

        itemString.Append(aItemString);

        }

    else

        {

        itemString.Append(aItemString.Left(KMaxWordLength));

        }

    ReplaceCharacters(itemString, KQuestion, TChar('\t'));

    ReplaceCharacters(itemString, KStar, TChar('\r'));

    CnvKatakana(searchText);

    CnvKatakana(itemString);

    TInt length = itemString.Length();

    for(int i=0;i<length;i++)

        {

        if (i==0 || IsFindWordSeparator(aItemString[i-1]))

            {

            if (itemString.Mid(i).MatchC(searchText) != KErrNotFound)

                {

                return i;

                }

            }

        }

    return KErrNotFound;

    }

// -----------------------------------------------------------------------------

// CFindUtilJapanese::IsMatch

// (other items were commented in a header).

// This method is called by MatchRefineL(). 

// This method separates by 4 characters, and this method calls MyFindC().

// -----------------------------------------------------------------------------

//

TBool CFindUtilJapanese::IsMatch( const TDesC& aItemString, const TDesC& aSearchText)

    {

    TPtrC itemptr(aItemString);

    TPtrC searchptr(aSearchText);

    TBool match = EFalse;

    FOREVER 

        {

        // Loop invariant: itemptr is next character from ' ' or '-'

        // Loop invariant: seachptr is at beginning of searched item

        TInt val = MyFindC(itemptr,searchptr);

        if (val == 0)

            {

            match = ETrue;

            break;

            }

        if (val != KErrNotFound && IsFindWordSeparator(itemptr[val-1]))

            {

            match = ETrue;

            break;

            }

        // find the word separator characters from list item

        const TInt maxFindChar = 4;

        TChar findchar = KFullWidthSpace;

        TInt findindex;

        for (findindex=0; findindex < maxFindChar; findindex++)

            {

            switch(findindex)

                {

                case 0: findchar = (' ');  break;   // space

                case 1: findchar = KFullWidthSpace; break;   // full space

                case 2: findchar = ('-');  break;   // minus

                case 3: findchar = ('\t'); break;   // tab

                }

            const TInt findpos = itemptr.LocateF(findchar);

            if (findpos != KErrNotFound)

                {

                itemptr.Set(itemptr.Mid(findpos+1));

                break;

                }

            }

        if (findindex >= maxFindChar)

            {

            match = EFalse;

            break;

            }

        if (itemptr.Length() == 0)

            {

            match = EFalse;

            break;

            }

        }

    return match;

    }

// -----------------------------------------------------------------------------

// CFindUtilJapanese::CnvKatakana

// (other items were commented in a header).

// -----------------------------------------------------------------------------

//

void CFindUtilJapanese::CnvKatakana(TDes& aDes)

    {

    TInt len = aDes.Length();

    for (TInt i(0); i < len; i++)

        {

        TUint16& ch = aDes[i];

        if (ch >= KLitStartHiragana && ch <= KLitEndHiragana)

            {

            ch += (KLitStartKatakana - KLitStartHiragana);

            }

        }

    }

// -----------------------------------------------------------------------------

// CFindUtilJapanese::Match

// (other items were commented in a header).

// -----------------------------------------------------------------------------

//

TBool CFindUtilJapanese::Match(const TDesC& aContactsField, const TDesC& aWord)

    {

    if (!aContactsField.Length())

        {

        return EFalse;

        }

    TBuf<KMaxWordLength> searchText(aWord);

    TBuf<KMaxWordLength> itemString(aContactsField);

    searchText.Append(KDesWildCard);

    CnvKatakana(searchText);

    CnvKatakana(itemString);

    if (itemString.MatchC(searchText) != KErrNotFound)

        {

        return ETrue;

        }

    return EFalse;

    }

// -----------------------------------------------------------------------------

// CFindUtilJapanese::MatchRefineL

// (other items were commented in a header).

// -----------------------------------------------------------------------------

//

TBool CFindUtilJapanese::MatchRefineL( const TDesC& aItemString, const TDesC &aSearchText)

    {

    if ( aItemString.Length() == 0 )

        {

        return EFalse;

        }

    if ( aSearchText.Length() == 0 )

        {

        return ETrue;

        }

    return IsMatch(aItemString, aSearchText);

    }

// -----------------------------------------------------------------------------

// CFindUtilJapanese::IsWordValidForMatching

// (other items were commented in a header).

// -----------------------------------------------------------------------------

//

TBool CFindUtilJapanese::IsWordValidForMatching(const TDesC& /*aWord*/)

    {

    return ETrue;

    }

// -----------------------------------------------------------------------------

// CFindUtilJapanese::MatchAdaptiveRefineL

// (other items were commented in a header).

// -----------------------------------------------------------------------------

//  

TBool CFindUtilJapanese::MatchAdaptiveRefineL( const TDesC& /*aItemString*/, 

	                                           const TDesC& /*aSearchText*/,

	                                           HBufC*& /*aNextChars*/ )

	{	

  	return EFalse;	

	}

// ---------------------------------------------------------

// Match arithmetic for accurate search, special conversion 

// for aItemString is implemented with MFindStringConverter

// before the final match

// ---------------------------------------------------------

//

TBool CFindUtilJapanese::MatchRefineL( const TDesC& /*aItemString*/, const TDesC& /*aSearchText*/, 

                                       TMatchPolicy /*aPolicy*/, MFindStringConverter* /*aConverter*/)

    {

    return EFalse;

    }	

// ========================== OTHER EXPORTED FUNCTIONS =========================

// -----------------------------------------------------------------------------

// FindUtilFactoryFunctionL

// Factory function at first ordinal

// Returns: MFindUtil: It returns MFindUtil I/F.

// -----------------------------------------------------------------------------

//

EXPORT_C MFindUtil* FindUtilFactoryFunctionL()

    {

    return new( ELeave ) CFindUtilJapanese();

    }

//  End of File