codeeditor.h

#ifndef CODEEDITOR_H
#define CODEEDITOR_H

#include <QPlainTextEdit>

class LineNumberArea;

/**
 * @brief The CodeEditor class defines a text editor for code (used for specification and properties)
 */
class CodeEditor : public QPlainTextEdit
{
    Q_OBJECT

public:
    /**
     * @brief CodeEditor Constructor
     * @param parent The parent of this widget
     * @param spec Whether this code editor is to create a specification (else a property)
     */
    explicit CodeEditor(QWidget *parent = 0, bool spec = false);

    /**
     * @brief lineNumberAreaPaintEvent Paints the line number area on the screen
     * @param event A paint event
     */
    void lineNumberAreaPaintEvent(QPaintEvent *event);

    /**
     * @brief lineNumberAreaWidth Computes the width needed for the line number area
     * @return The width needed for the line number area
     */
    int lineNumberAreaWidth();

public slots:
    /**
     * @brief deleteChar Allows the user to delete text
     */
    void deleteChar();

protected:
    /**
     * @brief resizeEvent Resizes the line number area when the window is resized
     * @param e The resize event
     */
    void resizeEvent(QResizeEvent *event) override;

private:
    QWidget *lineNumberArea;

private slots:
    /**
     * @brief updateLineNumberAreaWidth Updates the width of the line number area
     */
    void updateLineNumberAreaWidth(int);

    /**
     * @brief updateLineNumberArea Updates the line number area after the scrollbar has been used
     * @param rect The rectangle that covers the line number area
     * @param dy The amount of pixels scrolled
     */
    void updateLineNumberArea(const QRect &, int);
};


/**
 * @brief The LineNumberArea class defines the area with line numbers in the code editor
 */
class LineNumberArea : public QWidget
{
public:
    /**
     * @brief LineNumberArea Constructor
     * @param editor The code editor this line number area belongs to
     */
    LineNumberArea(CodeEditor *editor);

    /**
     * @brief sizeHint Returns the recommended size of the widget
     * @return The recommended size of the widget
     */
    QSize sizeHint() const override;

protected:
    /**
     * @brief paintEvent Handles paint events
     * @param event A paint event
     */
    void paintEvent(QPaintEvent *event) override;

private:
    CodeEditor *codeEditor;
};

#endif // CODEEDITOR_H