ui: added setting for text encoding to preferences (issue #500)

* also fixed offset of source locations behind multibyte characters

src/lib_gui/qt/element/QtCodeField.cpp

@@ -2,6 +2,7 @@
 
 #include <QPainter>
 #include <QTextBlock>
+#include <QTextCodec>
 
 #include "data/location/SourceLocation.h"
 #include "data/location/SourceLocationFile.h"
@@ -47,8 +48,15 @@ QtCodeField::QtCodeField(
 		displayCode.pop_back();
 	}
 
-	setPlainText(QString::fromUtf8(displayCode.c_str()));
+	QTextCodec* codec = QTextCodec::codecForName(ApplicationSettings::getInstance()->getTextEncoding().c_str());
+	QString convertedDisplayCode(codec->toUnicode(displayCode.c_str()));
+	setPlainText(convertedDisplayCode);
 	createLineLengthCache();
+	if (displayCode.size() != convertedDisplayCode.length())
+	{
+		LOG_INFO("Converting displayed code to " + codec->name().toStdString() + " resulted in offset of source locations. Correcting this now.");
+		createMultibyteCharacterLocationCache();
+	}
 
 	this->setMouseTracking(true);
 
@@ -333,9 +341,12 @@ void QtCodeField::createAnnotations(std::shared_ptr<SourceLocationFile> location
 			}
 			else if (startLocation->getLineNumber() <= endLineNumber)
 			{
-				annotation.start = toTextEditPosition(startLocation->getLineNumber(), startLocation->getColumnNumber() - 1);
-				annotation.startLine = startLocation->getLineNumber();
-				annotation.startCol = startLocation->getColumnNumber() - 1;
+				const int startLine = startLocation->getLineNumber();
+				const int startCol = getColumnCorrectedForMultibyteCharacters(startLine, startLocation->getColumnNumber() - 1);
+
+				annotation.start = toTextEditPosition(startLine, startCol);
+				annotation.startLine = startLine;
+				annotation.startCol = startCol;
 			}
 			else
 			{
@@ -351,9 +362,12 @@ void QtCodeField::createAnnotations(std::shared_ptr<SourceLocationFile> location
 			}
 			else if (endLocation->getLineNumber() >= m_startLineNumber)
 			{
-				annotation.end = toTextEditPosition(endLocation->getLineNumber(), endLocation->getColumnNumber());
-				annotation.endLine = endLocation->getLineNumber();
-				annotation.endCol = endLocation->getColumnNumber();
+				const int endLine = endLocation->getLineNumber();
+				const int endCol = getColumnCorrectedForMultibyteCharacters(endLine, endLocation->getColumnNumber());
+
+				annotation.end = toTextEditPosition(endLine, endCol);
+				annotation.endLine = endLine;
+				annotation.endCol = endCol;
 			}
 			else
 			{
@@ -641,3 +655,40 @@ void QtCodeField::createLineLengthCache()
 		m_endTextEditPosition += it.length();
 	}
 }
+
+void QtCodeField::createMultibyteCharacterLocationCache()
+{
+	m_multibyteCharacterLocations.clear();
+	QTextCodec* codec = QTextCodec::codecForName(ApplicationSettings::getInstance()->getTextEncoding().c_str());
+
+	for (QTextBlock itLine = document()->begin(); itLine != document()->end(); itLine = itLine.next())
+	{
+		std::vector<std::pair<int, int>> columnsToOffsets;
+		const QString line = itLine.text();
+		for (int i = 0; i < line.size(); i++)
+		{
+			if (line[i].unicode() > 127)
+			{
+				int ss = codec->fromUnicode(line[i]).size();
+				columnsToOffsets.push_back(std::make_pair(i, ss));
+			}
+		}
+		m_multibyteCharacterLocations.push_back(columnsToOffsets);
+	}
+}
+
+int QtCodeField::getColumnCorrectedForMultibyteCharacters(const int line, int column) const
+{
+	const int relativeLineNumber = line - m_startLineNumber;
+	if (relativeLineNumber < m_multibyteCharacterLocations.size())
+	{
+		for (const std::pair<int, int> m_multibyteCharacterLocation : m_multibyteCharacterLocations[relativeLineNumber])
+		{
+			if (column > m_multibyteCharacterLocation.first)
+			{
+				column -= m_multibyteCharacterLocation.second - 1;
+			}
+		}
+	}
+	return column;
+}

src/lib_gui/qt/element/QtCodeField.h

@@ -105,6 +105,8 @@ private:
 	static std::vector<AnnotationColor> s_annotationColors;
 
 	void createLineLengthCache();
+	void createMultibyteCharacterLocationCache();
+	int getColumnCorrectedForMultibyteCharacters(const int line, int column) const;
 
 	const uint m_startLineNumber;
 	const std::string m_code;
@@ -114,6 +116,7 @@ private:
 	QtHighlighter* m_highlighter;
 
 	std::vector<int> m_lineLengths;
+	std::vector<std::vector<std::pair<int, int>>> m_multibyteCharacterLocations;
 
 	int m_endTextEditPosition;
 };

src/lib_gui/qt/element/QtFontPicker.cpp

@@ -1,7 +1,6 @@
 #include "qt/element/QtFontPicker.h"
 
 #include <QHBoxLayout>
-#include <QPainter>
 #include <QFontComboBox>
 
 QtFontPicker::QtFontPicker(QWidget *parent)
@@ -15,7 +14,7 @@ QtFontPicker::QtFontPicker(QWidget *parent)
 	layout->setAlignment(Qt::AlignTop);
 
 	m_box = new QFontComboBox();
-	m_box->setFontFilters( QFontComboBox::MonospacedFonts );
+	m_box->setFontFilters(QFontComboBox::MonospacedFonts);
 	m_box->setEditable(false);
 
 	layout->addWidget(m_box);
@@ -33,4 +32,3 @@ void QtFontPicker::setText(QString text)
 {
 	m_box->setCurrentText(text);
 }
-

src/lib_gui/qt/element/QtTextEncodingPicker.cpp

@@ -0,0 +1,39 @@
+#include "qt/element/QtTextEncodingPicker.h"
+
+#include <QHBoxLayout>
+#include <QTextCodec>
+#include <QFontComboBox>
+
+QtTextEncodingPicker::QtTextEncodingPicker(QWidget *parent)
+	: QWidget(parent)
+{
+	setObjectName("picker");
+
+	QBoxLayout* layout = new QHBoxLayout();
+	layout->setSpacing(0);
+	layout->setContentsMargins(1, 1, 1, 1);
+	layout->setAlignment(Qt::AlignTop);
+
+	m_box = new QComboBox();
+	for (int mib : QTextCodec::availableMibs())
+	{
+		m_box->addItem(QTextCodec::codecForMib(mib)->name());
+	}
+	m_box->setEditable(false);
+
+	layout->addWidget(m_box);
+
+	setLayout(layout);
+	setSizePolicy(sizePolicy().horizontalPolicy(), QSizePolicy::Fixed);
+}
+
+QString QtTextEncodingPicker::getText()
+{
+	return m_box->currentText();
+}
+
+void QtTextEncodingPicker::setText(QString text)
+{
+	m_box->setCurrentText(text);
+}
+

src/lib_gui/qt/element/QtTextEncodingPicker.h

@@ -0,0 +1,23 @@
+#ifndef QT_TEXT_ENCODING_PICKER_H
+#define QT_TEXT_ENCODING_PICKER_H
+
+#include <QWidget>
+
+class QComboBox;
+
+class QtTextEncodingPicker
+	: public QWidget
+{
+	Q_OBJECT
+
+public:
+	QtTextEncodingPicker(QWidget *parent);
+
+	QString getText();
+	void setText(QString text);
+
+private:
+	QComboBox* m_box;
+};
+
+#endif // QT_TEXT_ENCODING_PICKER_H