Untangle saving TTI files into new file

The saving code is an attempt to be page function and page coding
agnostic so the same code can save (G)POP, (G)DRCS and MOT pages in
the future.

loadsave will be the home of page loading, URL exporting and also for
importing and exporting of other teletext file formats.

document.cpp

@@ -147,34 +147,6 @@ void TeletextDocument::loadDocument(QFile *inFile)
 	subPageSelected();
 }
 
-void TeletextDocument::saveDocument(QTextStream *outStream)
-{
-	if (!m_description.isEmpty())
-		*outStream << "DE," << m_description << endl;
-	//TODO DS and SP commands
-
-	int subPageNumber = m_subPages.size()>1;
-
-	for (auto &subPage : m_subPages) {
-		subPage->savePage(outStream, m_pageNumber, subPageNumber++);
-		if ((subPage->fastTextLinkPageNumber(0) & 0x0ff) != 0x0ff) {
-			*outStream << "FL,";
-			for (int i=0; i<6; i++) {
-				// Stored as page link with relative magazine number, convert to absolute page number for display
-				int absoluteLinkPageNumber = subPage->fastTextLinkPageNumber(i) ^ (m_pageNumber & 0x700);
-				// Fix magazine 0 to 8
-				if ((absoluteLinkPageNumber & 0x700) == 0x000)
-					absoluteLinkPageNumber |= 0x800;
-
-				*outStream << QString("%1").arg(absoluteLinkPageNumber, 3, 16, QChar('0'));
-				if (i<5)
-					*outStream << ',';
-			}
-			*outStream << endl;
-		}
-	}
-}
-
 void TeletextDocument::selectSubPageIndex(int newSubPageIndex, bool forceRefresh)
 {
 	// forceRefresh overrides "beyond the last subpage" check, so inserting a subpage after the last one still shows - dangerous workaround?

document.h

@@ -48,8 +48,8 @@ public:
 //	void setPacketCoding(PacketCodingEnum);
 
 	void loadDocument(QFile *);
-	void saveDocument(QTextStream *);
 	int numberOfSubPages() const { return m_subPages.size(); }
+	LevelOnePage* subPage(int p) const { return m_subPages[p]; }
 	LevelOnePage* currentSubPage() const { return m_subPages[m_currentSubPageIndex]; }
 	int currentSubPageIndex() const { return m_currentSubPageIndex; }
 	void selectSubPageIndex(int, bool=false);

levelonepage.cpp

@@ -42,7 +42,7 @@ LevelOnePage::LevelOnePage(const PageBase &other)
 	localEnhance.reserve(208);
 	clearPage();
 
-	for (int i=PageBase::C4ErasePage; i<=PageBase::C11SerialMagazine; i++)
+	for (int i=PageBase::C4ErasePage; i<=PageBase::C14NOS; i++)
 		setControlBit(i, other.controlBit(i));
 	for (int i=0; i<90; i++)
 		if (other.packetNeededArrayIndex(i))
@@ -55,12 +55,12 @@ void LevelOnePage::clearPage()
 	for (int r=0; r<25; r++)
 		for (int c=0; c<40; c++)
 			m_level1Page[r][c] = 0x20;
-	for (int i=0; i<8; i++) {
+	for (int i=C4ErasePage; i<=C14NOS; i++)
 		setControlBit(i, false);
+	for (int i=0; i<8; i++)
 		m_composeLink[i] = { (i<4) ? i : 0, false, i>=4, 0x0ff, 0x0000 };
-	}
 	for (int i=0; i<6; i++)
-		m_fastTextLink[i] = { 0x0ff, 0x37f7 };
+		m_fastTextLink[i] = { 0x0ff, 0x3f7f };
 
 /*	m_subPageNumber = 0x0000; */
 	m_cycleValue = 8;
@@ -256,7 +256,8 @@ bool LevelOnePage::setPacket(int packetNumber, int designationCode, QByteArray p
 		int CLUToffset = (designationCode == 0) ? 16 : 0;
 
 		m_defaultCharSet = ((packetContents.at(2) >> 4) & 0x3) | ((packetContents.at(3) << 2) & 0xc);
-		m_defaultNOS = (packetContents.at(2) >> 1) & 0x7;
+		// Don't set m_defaultNOS directly as we need to keep control bits in subclass in sync
+		setDefaultNOS((packetContents.at(2) >> 1) & 0x7);
 		m_secondCharSet = ((packetContents.at(3) >> 5) & 0x1) | ((packetContents.at(4) << 1) & 0xe);
 		m_secondNOS = (packetContents.at(3) >> 2) & 0x7;
 
@@ -292,18 +293,13 @@ bool LevelOnePage::packetNeeded(int packetNumber, int designationCode) const
 	if (packetNumber == 26)
 		return ((localEnhance.size()+12) / 13) > designationCode;
 
-	// FIXME don't save this raw packet yet as TeletextDocument::savePage currently uses fastTextLinkPageNumber
-	// to put the FL commands into the .tti file
-	// When we separate out loading and saving into its own cpp file, that will then become responsible for
-	// converting this packet into an FL command itself
-
-/*	if (packetNumber == 27 && designationCode == 0) {
+	if (packetNumber == 27 && designationCode == 0) {
 		for (int i=0; i<6; i++)
 			if ((m_fastTextLink[i].pageNumber & 0x0ff) != 0xff)
 				return true;
 
 		return false;
-	}*/
+	}
 
 	if (packetNumber == 27 && (designationCode == 4 || designationCode == 5)) {
 		for (int i=0; i<(designationCode == 4 ? 6 : 2); i++) {
@@ -363,7 +359,7 @@ void LevelOnePage::loadPagePacket(QByteArray &inLine)
 			setPacket(lineNumber, inLine);
 		} else {
 			int designationCode = inLine.at(0) & 0x3f;
-			if (inLine.size() < 40)
+			if (inLine.size() < 40) {
 				// OL is too short!
 				if (lineNumber == 26) {
 					// For a too-short enhancement triplets OL, first trim the line down to nearest whole triplet
@@ -374,6 +370,7 @@ void LevelOnePage::loadPagePacket(QByteArray &inLine)
 				} else
 					// For other triplet OLs and Hamming 8/4 OLs, just pad with zero data
 					inLine.leftJustified(40, '@');
+			}
 			for (int i=1; i<=39; i++)
 				inLine[i] = inLine.at(i) & 0x3f;
 			setPacket(lineNumber, designationCode, inLine);
@@ -381,48 +378,6 @@ void LevelOnePage::loadPagePacket(QByteArray &inLine)
 	}
 }
 
-void LevelOnePage::savePage(QTextStream *outStream, int pageNumber, int subPageNumber)
-{
-	auto writePacketsWithDesignationCodes=[&](int packetNumber)
-	{
-		for (int i=0; i<=16; i++)
-			if (packetNeeded(packetNumber, i)) {
-				QByteArray outLine = packet(packetNumber, i);
-
-				*outStream << QString("OL,%1,").arg(packetNumber);
-				outLine[0] = i | 0x40;
-				for (int c=1; c<outLine.size(); c++)
-					outLine[c] = outLine.at(c) | 0x40;
-				*outStream << outLine << endl;
-			}
-	};
-
-	*outStream << QString("PN,%1%2").arg(pageNumber, 3, 16, QChar('0')).arg(subPageNumber & 0xff, 2, 16, QChar('0')) << endl;
-	*outStream << QString("SC,%1").arg(subPageNumber, 4, 16, QChar('0')) << endl;
-	*outStream << QString("PS,%1").arg(0x8000 | controlBitsToPS(), 4, 16, QChar('0')) << endl;
-	*outStream << QString("CT,%1,%2").arg(m_cycleValue).arg(m_cycleType==CTcycles ? 'C' : 'T') << endl;
-	// TODO RE and maybe FLOF?
-
-	// BUG FL commands may clash with X/27/0 packets that specify links manually (e.g. with subcodes)
-	writePacketsWithDesignationCodes(27);
-	writePacketsWithDesignationCodes(28);
-	writePacketsWithDesignationCodes(26);
-
-	for (int r=1; r<25; r++)
-		if (packetNeeded(r)) {
-			QByteArray outLine = packet(r);
-
-			*outStream << QString("OL,%1,").arg(r);
-			for (int c=0; c<outLine.size(); c++)
-				if (outLine.at(c) < 0x20) {
-					outLine[c] = outLine.at(c) | 0x40;
-					outLine.insert(c, 0x1b);
-					c++;
-				}
-			*outStream << outLine << endl;
-		}
-}
-
 int LevelOnePage::controlBitsToPS() const
 {
 	//TODO map page language for regions other than 0
@@ -492,7 +447,14 @@ QString LevelOnePage::exportURLHash(QString pageHash)
 void LevelOnePage::setCycleValue(int newValue) { m_cycleValue = newValue; };
 void LevelOnePage::setCycleType(CycleTypeEnum newType) { m_cycleType = newType; }
 void LevelOnePage::setDefaultCharSet(int newDefaultCharSet) { m_defaultCharSet = newDefaultCharSet; }
-void LevelOnePage::setDefaultNOS(int newDefaultNOS) { m_defaultNOS = newDefaultNOS; }
+
+void LevelOnePage::setDefaultNOS(int defaultNOS)
+{
+	m_defaultNOS = defaultNOS;
+	setControlBit(C12NOS, defaultNOS & 1);
+	setControlBit(C13NOS, defaultNOS & 2);
+	setControlBit(C14NOS, defaultNOS & 4);
+}
 
 void LevelOnePage::setSecondCharSet(int newSecondCharSet)
 {

levelonepage.h

@@ -50,7 +50,6 @@ public:
 
 	void clearPage();
 	void loadPagePacket(QByteArray &);
-	void savePage(QTextStream *, int, int);
 	QString exportURLHash(QString);
 
 /*	void setSubPageNumber(int); */

loadsave.cpp

@@ -0,0 +1,158 @@
+/*
+ * Copyright (C) 2020 Gavin MacGregor
+ *
+ * This file is part of QTeletextMaker.
+ *
+ * QTeletextMaker is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * QTeletextMaker is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with QTeletextMaker.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "loadsave.h"
+
+#include <QSaveFile>
+
+#include "document.h"
+#include "levelonepage.h"
+#include "pagebase.h"
+
+// Used by TTI and hashstring
+int controlBitsToPS(PageBase *subPage)
+{
+	// C4 Erase page is stored in bit 14
+	int pageStatus = 0x8000 | (subPage->controlBit(PageBase::C4ErasePage) << 14); 
+	// C5 to C11 stored in order from bits 1 to 6
+	for (int i=PageBase::C5Newsflash; i<=PageBase::C11SerialMagazine; i++)
+		pageStatus |= subPage->controlBit(i) << (i-1);
+	// Apparently the TTI format stores the NOS bits backwards
+	pageStatus |= subPage->controlBit(PageBase::C12NOS) << 9;
+	pageStatus |= subPage->controlBit(PageBase::C13NOS) << 8;
+	pageStatus |= subPage->controlBit(PageBase::C14NOS) << 7;
+	return pageStatus;
+}
+
+void saveTTI(QSaveFile &file, const TeletextDocument &document)
+{
+	int p;
+	QTextStream outStream(&file);
+
+	auto write7bitPacket=[&](int packetNumber)
+	{
+		if (document.subPage(p)->packetNeeded(packetNumber)) {
+			QByteArray outLine = document.subPage(p)->packet(packetNumber);
+
+			outStream << QString("OL,%1,").arg(packetNumber);
+			for (int c=0; c<outLine.size(); c++)
+				if (outLine.at(c) < 0x20) {
+					// TTI files are plain text, so put in escape followed by control code with bit 6 set
+					outLine[c] = outLine.at(c) | 0x40;
+					outLine.insert(c, 0x1b);
+					c++;
+				}
+			outStream << outLine << Qt::endl;
+		}
+	};
+
+	auto writeHammingPacket=[&](int packetNumber, int designationCode=0)
+	{
+		if (document.subPage(p)->packetNeeded(packetNumber, designationCode)) {
+			QByteArray outLine = document.subPage(p)->packet(packetNumber, designationCode);
+
+			outStream << QString("OL,%1,").arg(packetNumber);
+			// TTI stores raw values with bit 7 set, doesn't do Hamming encoding
+			outLine[0] = designationCode | 0x40;
+			for (int c=1; c<outLine.size(); c++)
+				outLine[c] = outLine.at(c) | 0x40;
+			outStream << outLine << Qt::endl;
+		}
+	};
+
+	outStream.setCodec("ISO-8859-1");
+
+	if (!document.description().isEmpty())
+		outStream << "DE," << document.description() << Qt::endl;
+
+	// TODO DS and SP commands
+
+	// If there's just one subpage then we save it with a subcode of 0000
+	// otherwise start with a subcode of 0001
+	int subPageNumber = document.numberOfSubPages() > 1;
+
+	for (p=0; p<document.numberOfSubPages(); p++) {
+
+		outStream << QString("PN,%1%2").arg(document.pageNumber(), 3, 16, QChar('0')).arg(subPageNumber & 0xff, 2, 16, QChar('0')) << Qt::endl;
+		// Magazine Organisation Table and Magazine Inventory Page don't have subpages
+		if (document.pageFunction() != TeletextDocument::PFMOT && document.pageFunction() != TeletextDocument::PFMIP)
+			outStream << QString("SC,%1").arg(subPageNumber, 4, 16, QChar('0')) << Qt::endl;
+
+		outStream << QString("PS,%1").arg(0x8000 | controlBitsToPS(document.subPage(p)), 4, 16, QChar('0')) << Qt::endl;
+
+		if (document.pageFunction() == TeletextDocument::PFLevelOnePage)
+			// Assume that only Level One Pages have configurable cycle times
+			outStream << QString("CT,%1,%2").arg(document.subPage(p)->cycleValue()).arg(document.subPage(p)->cycleType()==LevelOnePage::CTcycles ? 'C' : 'T') << Qt::endl;
+		else
+			// X/28/0 specifies page function and coding but the PF command
+			// should make it obvious to a human that this isn't a Level One Page
+			outStream << QString("PF,%1,%2").arg(document.pageFunction()).arg(document.packetCoding()) << Qt::endl;
+
+		bool writeFLCommand = false;
+		if (document.pageFunction() == TeletextDocument::PFLevelOnePage && document.subPage(p)->packetNeeded(27,0)) {
+			// Subpage has FastText links - if any link to a specific subpage, we need to write X/27/0 as raw
+			// otherwise we write the links as a human-readable FL command later on
+			writeFLCommand = true;
+			// TODO uncomment this when we can edit FastText subpage links
+			/*for (int i=0; i<6; i++)
+				if (document.subPage(p)->fastTextLinkSubPageNumber(i) != 0x3f7f) {
+					writeFLCommand = false;
+					break;
+				}*/
+		}
+
+		// X27 then X28 always come first
+		for (int i=(writeFLCommand ? 1 : 0); i<16; i++)
+			writeHammingPacket(27, i);
+		for (int i=0; i<16; i++)
+			writeHammingPacket(28, i);
+
+		if (document.packetCoding() == TeletextDocument::Coding7bit) {
+			// For 7 bit coding i.e. Level One Pages, X/26 are written before X/1 to X/25
+			for (int i=0; i<16; i++)
+				writeHammingPacket(26, i);
+			for (int i=1; i<=24; i++)
+				write7bitPacket(i);
+		} else {
+			// For others (especially (G)POP pages) X/1 to X/25 are written before X/26
+			for (int i=1; i<=25; i++)
+				writeHammingPacket(i);
+			for (int i=0; i<16; i++)
+				writeHammingPacket(26, i);
+		}
+
+		if (writeFLCommand) {
+			outStream << "FL,";
+			for (int i=0; i<6; i++) {
+				// Stored as page link with relative magazine number, convert to absolute page number for display
+				int absoluteLinkPageNumber = document.subPage(p)->fastTextLinkPageNumber(i) ^ (document.pageNumber() & 0x700);
+				// Fix magazine 0 to 8
+				if ((absoluteLinkPageNumber & 0x700) == 0x000)
+					absoluteLinkPageNumber |= 0x800;
+
+				outStream << QString("%1").arg(absoluteLinkPageNumber, 3, 16, QChar('0'));
+				if (i<5)
+					outStream << ',';
+			}
+			outStream << Qt::endl;
+		}
+
+		subPageNumber++;
+	}
+}

loadsave.h

@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2020 Gavin MacGregor
+ *
+ * This file is part of QTeletextMaker.
+ *
+ * QTeletextMaker is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * QTeletextMaker is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with QTeletextMaker.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#ifndef LOADSAVE_H
+#define LOADSAVE_H
+
+#include <QSaveFile>
+
+#include "document.h"
+#include "pagebase.h"
+
+int controlBitsToPS(PageBase *);
+void saveTTI(QSaveFile &, const TeletextDocument &);
+
+#endif

mainwindow.cpp

@@ -24,6 +24,7 @@
 #include <QMenuBar>
 #include <QMessageBox>
 #include <QRadioButton>
+#include <QSaveFile>
 #include <QScreen>
 #include <QSettings>
 #include <QStatusBar>
@@ -33,6 +34,7 @@
 #include "mainwindow.h"
 
 #include "levelonecommands.h"
+#include "loadsave.h"
 #include "mainwidget.h"
 #include "pageenhancementsdockwidget.h"
 #include "pageoptionsdockwidget.h"
@@ -762,18 +764,23 @@ void MainWindow::openRecentFile()
 
 bool MainWindow::saveFile(const QString &fileName)
 {
-	QFile file(fileName);
-	if (!file.open(QFile::WriteOnly | QFile::Text)) {
-		QMessageBox::warning(this, tr("QTeletextMaker"), tr("Cannot write file %1:\n%2.").arg(QDir::toNativeSeparators(fileName), file.errorString()));
+	QString errorMessage;
+
+	QApplication::setOverrideCursor(Qt::WaitCursor);
+	QSaveFile file(fileName);
+	if (file.open(QFile::WriteOnly | QFile::Text)) {
+		saveTTI(file, *m_textWidget->document());
+		if (!file.commit())
+			errorMessage = tr("Cannot write file %1:\n%2.") .arg(QDir::toNativeSeparators(fileName), file.errorString());
+	} else
+		errorMessage = tr("Cannot open file %1 for writing:\n%2.").arg(QDir::toNativeSeparators(fileName), file.errorString());
+	QApplication::restoreOverrideCursor();
+
+	if (!errorMessage.isEmpty()) {
+		QMessageBox::warning(this, tr("QTeletextMaker"), errorMessage);
 		return false;
 	}
 
-	QTextStream out(&file);
-	out.setCodec("ISO-8859-1");
-	QApplication::setOverrideCursor(Qt::WaitCursor);
-	m_textWidget->document()->saveDocument(&out);
-	QApplication::restoreOverrideCursor();
-
 	setCurrentFile(fileName);
 	statusBar()->showMessage(tr("File saved"), 2000);
 	return true;

pagebase.cpp

@@ -26,13 +26,13 @@ PageBase::PageBase()
 	// We use nullptrs to keep track of allocated packets, so initialise them this way
 	for (int i=0; i<90; i++)
 		m_packets[i] = nullptr;
-	for (int i=PageBase::C4ErasePage; i<=PageBase::C11SerialMagazine; i++)
+	for (int i=PageBase::C4ErasePage; i<=PageBase::C14NOS; i++)
 		m_controlBits[i] = false;
 }
 
 PageBase::PageBase(const PageBase &other)
 {
-	for (int i=PageBase::C4ErasePage; i<=PageBase::C11SerialMagazine; i++)
+	for (int i=PageBase::C4ErasePage; i<=PageBase::C14NOS; i++)
 		setControlBit(i, other.controlBit(i));
 	for (int i=0; i<90; i++)
 		if (other.packetNeededArrayIndex(i))

pagebase.h

@@ -28,7 +28,7 @@ class PageBase //: public QObject
 	//Q_OBJECT
 
 public:
-	enum ControlBitsEnum { C4ErasePage, C5Newsflash, C6Subtitle, C7SuppressHeader, C8Update, C9InterruptedSequence, C10InhibitDisplay, C11SerialMagazine };
+	enum ControlBitsEnum { C4ErasePage, C5Newsflash, C6Subtitle, C7SuppressHeader, C8Update, C9InterruptedSequence, C10InhibitDisplay, C11SerialMagazine, C12NOS, C13NOS, C14NOS };
 
 	PageBase();
 	PageBase(const PageBase &);
@@ -49,7 +49,7 @@ public:
 	bool setControlBit(int, bool);
 
 private:
-	bool m_controlBits[8];
+	bool m_controlBits[11];
 	QByteArray *m_packets[90]; // X/0 to X/25, plus 16 packets for X/26, another 16 for X/27, for X28 and for X/29
 };
 

qteletextmaker.pro

@@ -4,6 +4,7 @@ requires(qtConfig(filedialog))
 HEADERS       = document.h \
                 levelonecommands.h \
                 levelonepage.h \
+                loadsave.h \
                 mainwidget.h \
                 mainwindow.h \
                 pagebase.h \
@@ -17,6 +18,7 @@ HEADERS       = document.h \
 SOURCES       = document.cpp \
                 levelonecommands.cpp \
                 levelonepage.cpp \
+                loadsave.cpp \
                 main.cpp \
                 mainwidget.cpp \
                 mainwindow.cpp \