ui: Improved QtCodeView to annotate code

Added some features to QTCodeSnippet:
* Code is now annotated using information from TokenLocationFile
* Start of line numbering can be set
* Clicking on an annotation in the code gives the corresponding Token Id

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src/app/qt/element/QtCodeSnippet.cpp

@@ -0,0 +1,185 @@
+#include "qt/element/QtCodeSnippet.h"
+
+#include <QtWidgets>
+
+#include "data/location/TokenLocation.h"
+#include "data/location/TokenLocationFile.h"
+#include "data/location/TokenLocationLine.h"
+#include "qt/view/QtCodeView.h"
+
+QtCodeSnippet::LineNumberArea::LineNumberArea(QtCodeSnippet *codeSnippet)
+	: QWidget(codeSnippet)
+	, m_codeSnippet(codeSnippet)
+{
+}
+
+QtCodeSnippet::LineNumberArea::~LineNumberArea()
+{
+}
+
+QSize QtCodeSnippet::LineNumberArea::sizeHint() const
+{
+	return QSize(m_codeSnippet->lineNumberAreaWidth(), 0);
+}
+
+void QtCodeSnippet::LineNumberArea::paintEvent(QPaintEvent *event)
+{
+	m_codeSnippet->lineNumberAreaPaintEvent(event);
+}
+
+
+QtCodeSnippet::QtCodeSnippet(QtCodeView* parentView, int startLineNumber, QWidget *parent)
+	: QPlainTextEdit(parent)
+	, m_parentView(parentView)
+	, m_startLineNumber(startLineNumber)
+{
+	m_lineNumberArea = new LineNumberArea(this);
+
+	connect(this, SIGNAL(blockCountChanged(int)), this, SLOT(updateLineNumberAreaWidth(int)));
+	connect(this, SIGNAL(updateRequest(QRect,int)), this, SLOT(updateLineNumberArea(QRect,int)));
+	connect(this, SIGNAL(cursorPositionChanged()), this, SLOT(clickTokenLocation()));
+
+	updateLineNumberAreaWidth(0);
+}
+
+QtCodeSnippet::~QtCodeSnippet()
+{
+}
+
+void QtCodeSnippet::lineNumberAreaPaintEvent(QPaintEvent *event)
+{
+	QPainter painter(m_lineNumberArea);
+	painter.fillRect(event->rect(), QColor(225,225,225));
+
+	QTextBlock block = firstVisibleBlock();
+	int blockNumber = block.blockNumber();
+	int top = static_cast<int>(blockBoundingGeometry(block).translated(contentOffset()).top());
+	int bottom = top + static_cast<int>(blockBoundingRect(block).height());
+
+	while (block.isValid() && top <= event->rect().bottom())
+	{
+		if (block.isVisible() && bottom >= event->rect().top())
+		{
+			QString number = QString::number(blockNumber + m_startLineNumber);
+			painter.setPen(Qt::black);
+			painter.drawText(0, top, m_lineNumberArea->width() - 1, fontMetrics().height(), Qt::AlignRight, number);
+		}
+
+		block = block.next();
+		top = bottom;
+		bottom = top + static_cast<int>(blockBoundingRect(block).height());
+		blockNumber++;
+	}
+}
+
+int QtCodeSnippet::lineNumberAreaWidth()
+{
+	int digits = 1;
+	int max = qMax(1, m_startLineNumber + blockCount());
+
+	while (max >= 10)
+	{
+		max /= 10;
+		digits++;
+	}
+
+	int width = 2 + fontMetrics().width(QLatin1Char('9')) * digits;
+	return width;
+}
+
+void QtCodeSnippet::annotateText(const TokenLocationFile& locationFile)
+{
+	QList<QTextEdit::ExtraSelection> extraSelections;
+
+	for (const TokenLocationFile::TokenLocationLinePairType& lineItem : locationFile.getTokenLocationLines())
+	{
+		for (const TokenLocationLine::TokenLocationPairType& locationItem : lineItem.second->getTokenLocations())
+		{
+			TokenLocation* location = locationItem.second.get();
+			if (!location->isStartTokenLocation())
+			{
+				continue;
+			}
+
+			Annotation annotation;
+			annotation.start = toTextEditPosition(location->getLineNumber(), location->getColumnNumber() - 1);
+			annotation.end = toTextEditPosition(
+				location->getEndTokenLocation()->getLineNumber(),
+				location->getEndTokenLocation()->getColumnNumber());
+			annotation.tokenId = location->getTokenId();
+			m_annotations.push_back(annotation);
+
+			QTextEdit::ExtraSelection selection;
+
+			QColor color = QColor(Qt::red);
+			color.setAlphaF(0.3f);
+			selection.format.setBackground(color);
+
+			selection.cursor = textCursor();
+			selection.cursor.clearSelection();
+			selection.cursor.setPosition(annotation.start);
+			selection.cursor.setPosition(annotation.end, QTextCursor::KeepAnchor);
+
+			extraSelections.append(selection);
+		}
+	}
+
+	setExtraSelections(extraSelections);
+}
+
+void QtCodeSnippet::resizeEvent(QResizeEvent *e)
+{
+	QPlainTextEdit::resizeEvent(e);
+
+	QRect cr = contentsRect();
+	m_lineNumberArea->setGeometry(QRect(cr.left(), cr.top(), lineNumberAreaWidth(), cr.height()));
+}
+
+void QtCodeSnippet::updateLineNumberAreaWidth(int /* newBlockCount */)
+{
+	setViewportMargins(lineNumberAreaWidth(), 0, 0, 0);
+}
+
+void QtCodeSnippet::updateLineNumberArea(const QRect &rect, int dy)
+{
+	if (dy)
+	{
+		m_lineNumberArea->scroll(0, dy);
+	}
+	else
+	{
+		m_lineNumberArea->update(0, rect.y(), m_lineNumberArea->width(), rect.height());
+	}
+
+	if (rect.contains(viewport()->rect()))
+	{
+		updateLineNumberAreaWidth(0);
+	}
+}
+
+void QtCodeSnippet::clickTokenLocation()
+{
+	int clickPosition = textCursor().position();
+	for (Annotation annotation : m_annotations)
+	{
+		if (clickPosition >= annotation.start && clickPosition <= annotation.end)
+		{
+			m_parentView->activateToken(annotation.tokenId);
+			return;
+		}
+	}
+}
+
+int QtCodeSnippet::toTextEditPosition(int lineNumber, int columnNumber) const
+{
+	lineNumber -= m_startLineNumber - 1;
+
+	int position = 0;
+	for (int i = 0; i < lineNumber - 1; i++)
+	{
+		position += document()->findBlockByLineNumber(i).length();
+	}
+	position += columnNumber;
+
+	return position;
+}

src/app/qt/element/QtCodeSnippet.h

@@ -0,0 +1,71 @@
+#ifndef QT_CODE_SNIPPET_H
+#define QT_CODE_SNIPPET_H
+
+#include <vector>
+
+#include <QPlainTextEdit>
+#include <QObject>
+
+#include "utility/types.h"
+
+class QPaintEvent;
+class QResizeEvent;
+class QSize;
+class QtCodeView;
+class QWidget;
+class TokenLocationFile;
+
+class QtCodeSnippet: public QPlainTextEdit
+{
+	Q_OBJECT
+
+public:
+	class LineNumberArea: public QWidget
+	{
+	public:
+		LineNumberArea(QtCodeSnippet *codeSnippet);
+		virtual ~LineNumberArea();
+
+		QSize sizeHint() const;
+
+	protected:
+		void paintEvent(QPaintEvent *event);
+
+	private:
+		QtCodeSnippet *m_codeSnippet;
+	};
+
+	QtCodeSnippet(QtCodeView* parentView, int startLineNumber, QWidget *parent = 0);
+	virtual ~QtCodeSnippet();
+
+	void lineNumberAreaPaintEvent(QPaintEvent *event);
+	int lineNumberAreaWidth();
+
+	void annotateText(const TokenLocationFile& locationFile);
+
+protected:
+	void resizeEvent(QResizeEvent *event);
+
+private slots:
+	void updateLineNumberAreaWidth(int newBlockCount);
+	void updateLineNumberArea(const QRect &, int);
+	void clickTokenLocation();
+
+private:
+	struct Annotation
+	{
+		int start;
+		int end;
+		Id tokenId;
+	};
+
+	int toTextEditPosition(int lineNumber, int columnNumber) const;
+
+	QWidget *m_lineNumberArea;
+	QtCodeView* m_parentView;
+
+	const int m_startLineNumber;
+	std::vector<Annotation> m_annotations;
+};
+
+#endif // QT_CODE_SNIPPET_H