393 

   394 

   395 /////////////////////////////////////////////////////////////////////////////////////////

   396 

   397 const char KStartSymbol[] = {'(', '<', '[', '{'};

   398 const char KEndSymbol[] = {')', '>', ']', '}'};

   399 

   400 TInt IndexFrom(const char* const aPtr, TInt aLength, TInt aChar)

   401     {

   402     for(TInt i=0; i<aLength; i++)

   403         {

   404         if(aPtr[i] == aChar) return i;

   405         }

   406 

   407     return KErrNotFound;

   408     }

   409 

   410 TBool HavePairedSymbol(const TDesC& aText, TInt aSmileyLength)

   411     {

   412     char stack[5];

   413     TInt pos = 0;

   414     

   415     TInt i = aText.Length() - 1;

   416     const TInt smileyPos = aText.Length() - aSmileyLength;

   417 

   418     for(TInt i=aText.Length()-1; i>=0; i--)

   419         {

   420         TInt index = IndexFrom(KEndSymbol, sizeof(KEndSymbol), aText[i]); // detect end symbol

   421         if(KErrNotFound != index) // push

   422             {

   423             stack[pos++] = KStartSymbol[index];

   424             }

   425         else if(pos) // detect start symbol

   426             {

   427             if(stack[pos-1] == aText[i]) // meet a start symbol

   428                 {

   429                 pos--;

   430                 if(!pos) return (smileyPos > i);

   431                 }

   432             }

   433 

   434         if(smileyPos == i) // smiley combination finished

   435             {

   436             if(!pos) return EFalse;

   437             }

   438         }

   439 

   440     return EFalse;

   441     }

   442 

   443 TBool IsPartOfUrl(const TDesC& aText)

   444     {

   445     const TInt end = aText.Length() - 1;

   446     TInt pos = end;

   447     while(pos > 0)

   448         {

   449         const TUint16 word = aText[--pos];

   450         if(word == ' ' || word == 0x2029)

   451             {

   452             break;

   453             }

   454         }

   455     

   456     TInt length = end - pos;

   457     if(length > 5)

   458         {

   459         TPtrC field(aText.Mid(pos,length));

   460         pos = field.Find(_L(":\\\\"));

   461         if(KErrNotFound == pos) pos = field.Find(_L("://"));

   462         if(KErrNotFound != pos)

   463             {

   464             return ETrue;

   465             }    

   466         }

   467     

   468     return EFalse;

   469     }

   470 

   471 TBool CSmileyModel::IsSmileyBySemanticAnalysis(const TDesC& aText, TInt aSmileyLength)

   472     {

   473     if(HavePairedSymbol(aText, aSmileyLength)) return EFalse;

   474 

   475     if(IsPartOfUrl(aText)) return EFalse;

   476 

   477     return ETrue;

   478     }