qmarkdowntextedit.h

/*
 * Copyright (c) 2014-2022 Patrizio Bekerle -- <patrizio@bekerle.com>
 *
 * This program 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; version 2 of the License.
 *
 * This program 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.
 *
 */

#pragma once

#include <QEvent>
#include <QPlainTextEdit>

#include "markdownhighlighter.h"
#include "qplaintexteditsearchwidget.h"

class LineNumArea;

class QMarkdownTextEdit : public QPlainTextEdit {
    Q_OBJECT

    friend class LineNumArea;

   public:
    enum AutoTextOption {
        None = 0x0000,

        // inserts closing characters for brackets and markdown characters
        BracketClosing = 0x0001,

        // removes matching brackets and markdown characters
        BracketRemoval = 0x0002
    };

    Q_DECLARE_FLAGS(AutoTextOptions, AutoTextOption)

    explicit QMarkdownTextEdit(QWidget *parent = nullptr,
                               bool initHighlighter = true);
    MarkdownHighlighter *highlighter();
    QPlainTextEditSearchWidget *searchWidget();
    void setIgnoredClickUrlSchemata(QStringList ignoredUrlSchemata);
    virtual void openUrl(const QString &urlString);
    QString getMarkdownUrlAtPosition(const QString &text, int position);
    void initSearchFrame(QWidget *searchFrame, bool darkMode = false);
    void setAutoTextOptions(AutoTextOptions options);
    void setHighlightingEnabled(bool enabled);
    static bool isValidUrl(const QString &urlString);
    void resetMouseCursor() const;
    void setReadOnly(bool ro);
    void doSearch(QString &searchText,
                  QPlainTextEditSearchWidget::SearchMode searchMode =
                      QPlainTextEditSearchWidget::SearchMode::PlainTextMode);
    void hideSearchWidget(bool reset);
    void updateSettings();
    void setLineNumbersCurrentLineColor(QColor color);
    void setLineNumbersOtherLineColor(QColor color);
    void setSearchWidgetDebounceDelay(uint debounceDelay);

    void setHighlightCurrentLine(bool set);
    bool highlightCurrentLine();

    void setCurrentLineHighlightColor(const QColor &c);
    QColor currentLineHighlightColor();

   public Q_SLOTS:
    void duplicateText();
    void setText(const QString &text);
    void setPlainText(const QString &text);
    void adjustRightMargin();
    void hide();
    bool openLinkAtCursorPosition();
    bool handleBackspaceEntered();
    void centerTheCursor();
    void undo();
    void moveTextUpDown(bool up);
    void setLineNumberEnabled(bool enabled);

   protected:
    QTextCursor _textCursor;
    MarkdownHighlighter *_highlighter = nullptr;
    bool _highlightingEnabled;
    QStringList _ignoredClickUrlSchemata;
    QPlainTextEditSearchWidget *_searchWidget;
    QWidget *_searchFrame;
    AutoTextOptions _autoTextOptions;
    bool _mouseButtonDown = false;
    bool _centerCursor = false;
    bool _highlightCurrentLine = false;
    QColor _currentLineHighlightColor = QColor();
    uint _debounceDelay = 0;

    bool eventFilter(QObject *obj, QEvent *event) override;
    QMargins viewportMargins();
    bool increaseSelectedTextIndention(
        bool reverse, const QString &indentCharacters = QChar('\t'));
    bool handleTabEntered(bool reverse,
                          const QString &indentCharacters = QChar('\t'));
    QMap<QString, QString> parseMarkdownUrlsFromText(const QString &text);
    bool handleReturnEntered();
    bool handleBracketClosing(const QChar openingCharacter,
                              QChar closingCharacter = QChar());
    bool bracketClosingCheck(const QChar openingCharacter,
                             QChar closingCharacter);
    bool quotationMarkCheck(const QChar quotationCharacter);
    void focusOutEvent(QFocusEvent *event) override;
    void paintEvent(QPaintEvent *e) override;
    bool handleCharRemoval(MarkdownHighlighter::RangeType type, int block, int position);
    void resizeEvent(QResizeEvent *event) override;
    void setLineNumberLeftMarginOffset(int offset);
    int _lineNumberLeftMarginOffset = 0;
    LineNumArea *lineNumberArea()
    {
        return _lineNumArea;
    }

   Q_SIGNALS:
    void urlClicked(QString url);
    void zoomIn();
    void zoomOut();

   private:
    void updateLineNumAreaGeometry();
    void updateLineNumberArea(const QRect rect, int dy);
    Q_SLOT void updateLineNumberAreaWidth(int);

   private:
    bool _handleBracketClosingUsed;
    LineNumArea *_lineNumArea;
};