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

QString encodeCssFont (const QFont& refFont)
{
   //-----------------------------------------------------------------------
   // This function assembles a CSS Font specification string from a QFont.
   // This supports most of the QFont attributes settable in the Qt 4.8 and 
   // Qt 5.3 QFontDialog.  
   //
   //   (1) Font Family
   //   (2) Font Weight (just bold or not)
   //   (3) Font Style  (possibly Italic or Oblique)
   //   (4) Font Size   (in either pixels or point)
   //   (5) Decorations (possibly Underline or Strikeout)
   //
   // Not supported: Writing System (e.g. Latin).
   //
   // See the corresponding decode function, below.
   //   QFont decodeCssFontString (const QString cssFontStr)
   //-----------------------------------------------------------------------

   QStringList fields; // CSS font attribute fields

   // ***************************************************
   // ***  (1) Font Family: Primary plus Substitutes  ***
   // ***************************************************

   const QString family = refFont.family();
   QStringList famSubs = QFont::substitutes (family);
   if (!famSubs.contains (family))
      famSubs.prepend (family);

   static const QChar DBL_QUOT ('"');
   const int famCnt = famSubs.count();
   for (int inx = 0; inx < famCnt; ++inx)
   {
      const QString fam = famSubs [inx];   
      if (fam.contains (' ') && !fam.startsWith (DBL_QUOT))
         famList << (DBL_QUOT + fam + DBL_QUOT);
      else
         famList << fam;
   }

   const QString famStr = QString ("font-family: ") + famList.join (", ");
   fields << famStr;

   // **************************************
   // ***  (2) Font Weight: Bold or Not  ***
   // **************************************

   const bool bold = refFont.bold();
   if (bold)
      fields << "font-weight: bold";
   
   // ****************************************************
   // ***  (3) Font Style: possibly Italic or Oblique  ***
   // ****************************************************

   const QFont::Style style = refFont.style();
   switch (style)
   {
      case QFont::StyleNormal:   break;
      case QFont::StyleItalic:   fields << "font-style: italic";  break;
      case QFont::StyleOblique:  fields << "font-style: oblique"; break;
   }

   // ************************************************
   // ***  (4) Font Size: either Pixels or Points  ***
   // ************************************************

   const int sizeInPixels = refFont.pixelSize();     // <= 0 if not defined.
   const double sizeInPoints = refFont.pointSizeF(); // <= 0 if not defined.
   if (sizeInPixels > 0)
      fields << QString ("font-size: %1px") .arg (sizeInPixels);
   else if (sizeInPoints > 0.0)
      fields << QString ("font-size: %1pt") .arg (sizeInPoints);

   // ***********************************************
   // ***  (5) Decorations: Underline, Strikeout  ***
   // ***********************************************

   const bool underline = refFont.underline();
   const bool strikeOut = refFont.strikeOut();

   if (underline && strikeOut)
      fields << "text-decoration-line: underline line-through"
   else (underline)
      fields << "text-decoration-line: underline"
   else if (strikeOut)
      fields << "text-decoration-line: line-through"

   const QString cssFontStr = fields.join ("; ");
   return cssStr;
}

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

QFont decodeCssFontString (const QString cssFontStr)
{
   //-----------------------------------------------------------------------
   // This function creates a QFont from the provided CSS Font specification 
   // string.  This supports most of the QFont attributes settable in the 
   // Qt 4.8 and Qt 5.3 QFontDialog.  
   //
   //   (1) Font Family
   //   (2) Font Weight (just bold or not)
   //   (3) Font Style  (possibly Italic or Oblique)
   //   (4) Font Size   (in either pixels or point)
   //   (5) Decorations (possibly Underline or Strikeout)
   //
   // Not supported (defaulted): Writing System (e.g. Latin).
   //
   // See the corresponding encode function, above. 
   //   QString encodeCssFont (const QFont&)
   //-----------------------------------------------------------------------

   QFont retFont;

   QStringList fields = cssFontStr .split (';');
   const int fieldCnt = fields.count();

   for (int inx = 0; inx < fieldCnt; ++inx)
   {
      const QString field = fields [inx] .trimmed();
      if (field.isEmpty()) continue;
      //----------------------------

      const QStringList keyAndValue = field.split (':');
      if (keyAndValue.count() != 2) continue; 
      //-------------------------------------
     
      const QString key = keyAndValue [0] .trimmed() .toLower();
      const QString val = keyAndValue [1] .trimmed();
      const QString valLower = val .toLower();

      // *************************
      // ***  (1) Font Family  ***
      // *************************

      if (key .contains ("font-family"))
      {
         QStringList famList = val.split (',');
         if (!famList.isEmpty())
         {
            // Use only the first family in a comma separated list
            QString fam = famList [0] .trimmed();

            // Remove leading and trailing double quotes
            static const QChar DBL_QUOT ('"');
            while (fam .startsWith (DBL_QUOT)) 
               fam = fam .mid (1) .trimmed();
            while (fam .endsWith (DBL_QUOT))
               fam = fam .chop (1) .trimmed();

            if (!fam.isEmpty())
               retFont .setFamily (fam);
         }
      }

      // ********************************
      // ***  (2) Font Weight (Bold)  ***
      // ********************************

      else if (key .contains ("font-weight"))
      {
          if (valLower .contains ("bold")) 
             refFont .setBold (true);
      }

      // ********************************************
      // ***  (3) Font Style (Italic or Oblique)  ***
      // ********************************************

      else if (key .contains ("font-style"))
      {
         if (valLower .contains ("italic"))
            refFont .setStyle (QFont::StyleItalic);
         else if (valLower .contains ("oblique"))
            refFont .setStyle (QFont::StyleOblique);
      }

      // ************************************************
      // ***  (4) Font Size: either Pixels or Points  ***
      // ************************************************

      else if (key .contains ("font-size"))
      {
         bool numOk (false);
         const QString numPart = valLower .chop (2);
         const double num = numPart.toDouble (&numOk);

         if (numOk && (num > 0.0))
         {
            if (valLower.endsWith ("px")) 
               refFont .setPixelSize (int (num));
            else if (valLower.endsWith ("pt"))
               refFont .setPointSizeF (num);
         }
      }

      // ***********************************************
      // ***  (5) Decorations: Underline, Strikeout  ***
      // ***********************************************

      else if (key .contains ("text-decoration"))  // CSS 3
      {
         if (valLower.contains ("underline"))
            refFont .setUnderline (true);
         if (valLower.contains ("line-through"))
            refFont .setStrikeOut (true);
      }

   } // end for (int inx = 0; inx < fieldCnt; ++inx)

   return refFont;
}

//---