Raise exam/level file version, compress XML level content

- due to new instrument support
- but compression gives almost 20 times file reduction

src/dialogs/tlevelselector.cpp

@@ -247,17 +247,27 @@ Tlevel TlevelSelector::getLevelFromFile(QFile &file) {
   level.name.clear();;
   if (file.open(QIODevice::ReadOnly)) {
         QDataStream in(&file);
-        in.setVersion(QDataStream::Qt_5_2);
         quint32 lv; // level version identifier
         in >> lv;
         bool wasLevelValid = true;
         bool wasLevelFile = true;
         auto levelVer = Tlevel::levelVersionNr(lv);
         if (levelVer == 1 || levelVer == 2) { // *.nel with binary data
+            in.setVersion(QDataStream::Qt_4_7);
             wasLevelValid = getLevelFromStream(in, level, lv);
-        } else if (levelVer > 2 && levelVer <= 4) { // *.nel in XML
+        } else if (levelVer > 2 && levelVer <= 5) { // *.nel in XML, from version 5 compressed
             Tlevel::EerrorType er;
-            QXmlStreamReader xml(in.device());
+            QXmlStreamReader xml;
+            if (levelVer >= 5) { // compressed level
+                in.setVersion(QDataStream::Qt_5_9);
+                auto arrayXML = file.readAll();
+                arrayXML.remove(0, 4);
+                auto unZipXml = qUncompress(arrayXML);
+                xml.addData(unZipXml);
+            } else { // bare text (XML)
+                in.setVersion(QDataStream::Qt_5_2);
+                xml.setDevice(in.device());
+            }
             if (!xml.readNextStartElement()) // open first XML node
               er = Tlevel::e_noLevelInXml;
             else
@@ -278,25 +288,26 @@ Tlevel TlevelSelector::getLevelFromFile(QFile &file) {
             return level;
         }
         file.close();
-         if (!wasLevelFile) {
-              auto m = QLatin1String("<br><font size=\"4\"><b>")
-                  + tr("File: %1 \n is not Nootka level file!").arg(file.fileName()).replace(QLatin1String("\n"), QLatin1String("<br>"))
-                  + QLatin1String("</b></font>");
-              emit warnMessage(m, Qt::red);
-              level.name.clear();
-              return level;
-         } else if (!wasLevelValid) {
-              auto m = QLatin1String("<br><font size=\"4\"><b>")
-              + tr("Level file\n %1 \n was corrupted and repaired!\n Check please, if its parameters are as expected.").arg(file.fileName())
-                  .replace(QLatin1String("\n"), QLatin1String("<br>")) + QLatin1String("</font>");
-              emit warnMessage(m, Qt::yellow);
-         }
-
-         if (wasLevelFile) {
-           if (level.clef.type() == Tclef::Bass_F_8down) {
-             qDebug() << "[TlevelSelector] OBSOLETE bass dropped clef detected. Converting level to ordinary bass clef.";
-             level.convFromDropedBass();
-           }
+
+        if (!wasLevelFile) {
+            auto m = QLatin1String("<br><font size=\"4\"><b>")
+                + tr("File: %1 \n is not Nootka level file!").arg(file.fileName()).replace(QLatin1String("\n"), QLatin1String("<br>"))
+                + QLatin1String("</b></font>");
+            emit warnMessage(m, Qt::red);
+            level.name.clear();
+            return level;
+        } else if (!wasLevelValid) {
+            auto m = QLatin1String("<br><font size=\"4\"><b>")
+            + tr("Level file\n %1 \n was corrupted and repaired!\n Check please, if its parameters are as expected.").arg(file.fileName())
+                .replace(QLatin1String("\n"), QLatin1String("<br>")) + QLatin1String("</font>");
+            emit warnMessage(m, Qt::yellow);
+        }
+
+        if (wasLevelFile) {
+          if (level.clef.type() == Tclef::Bass_F_8down) {
+            qDebug() << "[TlevelSelector] OBSOLETE bass dropped clef detected. Converting level to ordinary bass clef.";
+            level.convFromDropedBass();
+          }
         }
   } else {
       if (!file.fileName().isEmpty()) // skip empty file names (ignored by user)

src/libs/core/exam/texam.cpp

@@ -35,7 +35,9 @@
 
 
 /*static*/
-/** Versions history:
+/**
+ * Versions history:
+ *
  * 1. 0x95121702;
  *
  * 2. 0x95121704; (2012.07)
@@ -49,11 +51,15 @@
  *
  * 5. 0x9512170A (05.02.2018)
  *    - new instruments, melodies in Music XML, new mistake types - it can not be compatible with older versions
+ *
+ * 6. 0x9512170C (09.06.2021)
+ *    - ukulele support - opening with previous versions would cause problems
+ *
  */
 
 const qint32 Texam::examVersion = 0x95121702;
 const qint32 Texam::examVersion2 = 0x95121704;
-const qint32 Texam::currentVersion = 0x9512170A; // version 5
+const qint32 Texam::currentVersion = 0x9512170C; // version 5
 
 const quint16 Texam::maxAnswerTime = 65500;
 
@@ -236,7 +242,10 @@ Texam::EerrorType Texam::loadFromFile(const QString& fileName) {
 
       bool isExamFileOk = true;
       if (examVersionNr(ev) > 3) {
-          in.setVersion(QDataStream::Qt_5_2);
+          if (examVersionNr(ev) > 5)
+            in.setVersion(QDataStream::Qt_5_9);
+          else
+            in.setVersion(QDataStream::Qt_5_2);
           QByteArray arrayXML = file.readAll();
           arrayXML.remove(0, 4);
           QByteArray unZipXml = qUncompress(arrayXML);
@@ -416,7 +425,7 @@ Texam::EerrorType Texam::saveToFile(const QString& fileName) {
   QFile file(m_fileName);
   if (file.open(QIODevice::WriteOnly)) {
       QDataStream out(&file);
-      out.setVersion(QDataStream::Qt_5_2);
+      out.setVersion(QDataStream::Qt_5_9);
       out << currentVersion;
       QByteArray arrayXML;
       QXmlStreamWriter xml(&arrayXML);
@@ -427,7 +436,6 @@ Texam::EerrorType Texam::saveToFile(const QString& fileName) {
       xml.writeEndDocument();
 
       out << qCompress(arrayXML);
-  //     out << arrayXML;
 
       file.close();
   } else {

src/libs/core/exam/tlevel.cpp

@@ -31,7 +31,9 @@
 
 
 /*static-------------------------------------------------------------------------------------------*/
-/** Versions history:
+/**
+ * Versions history:
+ *
  * 1. 0x95121701
  *
  * 2. 0x95121703 (02.12.2013)
@@ -41,10 +43,13 @@
  * 3. 0x95121705 (22.06.2014) - XML stream - universal version
  *
  * 4. 0x95121707 (05.02.2018) - rhythms, new instruments, melodies in Music XML
+ *
+ * 5. 0x95121709 (09.06.2021) - compression and ukulele support
+ *
  */
 
 const qint32 Tlevel::levelVersion = 0x95121701;
-const qint32 Tlevel::currentVersion = 0x95121707;
+const qint32 Tlevel::currentVersion = 0x95121709; // Version 5
 
 
 int Tlevel::levelVersionNr(qint32 ver) {
@@ -596,12 +601,14 @@ bool Tlevel::saveToFile(Tlevel& level, const QString& levelFile) {
   QFile file(levelFile);
   if (file.open(QIODevice::WriteOnly)) {
       QDataStream out(&file);
-      out.setVersion(QDataStream::Qt_5_2);
+      out.setVersion(QDataStream::Qt_5_9);
       out << currentVersion;
-      QXmlStreamWriter xml(&file);
+      QByteArray arrayXML;
+      QXmlStreamWriter xml(&arrayXML);
+//       QXmlStreamWriter xml(&file);
 
-      xml.setAutoFormatting(true);
-      xml.setAutoFormattingIndent(2);
+//       xml.setAutoFormatting(true);
+//       xml.setAutoFormattingIndent(2);
       xml.writeStartDocument();
       xml.writeComment(QStringLiteral("\nXML file of Nootka exam level.\n"
                        "https://nootka.sourceforge.io\n"
@@ -610,6 +617,8 @@ bool Tlevel::saveToFile(Tlevel& level, const QString& levelFile) {
       level.writeToXml(xml);
       xml.writeEndDocument();
 
+      out << qCompress(arrayXML);
+
       file.close();
       return true;
   } else