File indexing completed on 2024-04-21 03:57:18

 /*
     SPDX-FileCopyrightText: 2010 Christoph Cullmann <cullmann@kde.org>
 
     SPDX-License-Identifier: LGPL-2.0-or-later
 */
 #ifndef KATE_TEXTBUFFER_H
 #define KATE_TEXTBUFFER_H
 
 #include <QList>
 #include <QObject>
 #include <QSet>
 #include <QString>
 
 #include "katetextblock.h"
 #include "katetexthistory.h"
 #include <ktexteditor_export.h>
 
 // encoding prober
 #include <KEncodingProber>
 
 namespace KTextEditor
 {
 class DocumentPrivate;
 }
 
 class KCompressionDevice;
 
 namespace Kate
 {
 class TextRange;
 class TextCursor;
 class TextBlock;
 
 constexpr int BufferBlockSize = 64;
 
 /**
  * Class representing a text buffer.
  * The interface is line based, internally the text will be stored in blocks of text lines.
  */
 class KTEXTEDITOR_EXPORT TextBuffer : public QObject
 {
     friend class TextCursor;
     friend class TextRange;
     friend class TextBlock;
 
     Q_OBJECT
 
 public:
     /**
      * End of line mode
      */
     enum EndOfLineMode { eolUnknown = -1, eolUnix = 0, eolDos = 1, eolMac = 2 };
 
     /**
      * Construct an empty text buffer.
      * Empty means one empty line in one block.
      * @param parent parent qobject
      */
     explicit TextBuffer(KTextEditor::DocumentPrivate *parent, bool alwaysUseKAuth = false);
 
     /**
      * Destruct the text buffer
      * Virtual, we allow inheritance
      */
     ~TextBuffer() override;
 
     /**
      * Clears the buffer, reverts to initial empty state.
      * Empty means one empty line in one block.
      * Virtual, can be overwritten.
      */
     virtual void clear();
 
     /**
      * Set encoding prober type for this buffer to use for load.
      * @param proberType prober type to use for encoding
      */
     void setEncodingProberType(KEncodingProber::ProberType proberType)
     {
         m_encodingProberType = proberType;
     }
 
     /**
      * Get encoding prober type for this buffer
      * @return currently in use prober type of this buffer
      */
     KEncodingProber::ProberType encodingProberType() const
     {
         return m_encodingProberType;
     }
 
     /**
      * Set fallback codec for this buffer to use for load.
      * @param codec fallback to use for encoding
      */
     void setFallbackTextCodec(const QString &codec)
     {
         m_fallbackTextCodec = codec;
     }
 
     /**
      * Get fallback codec for this buffer
      * @return currently in use fallback codec of this buffer
      */
     QString fallbackTextCodec() const
     {
         return m_fallbackTextCodec;
     }
 
     /**
      * Set codec for this buffer to use for load/save.
      * Loading might overwrite this, if it encounters problems and finds a better codec.
      * Might change BOM setting.
      * @param codec to use for encoding
      */
     void setTextCodec(const QString &codec);
 
     /**
      * Get codec for this buffer
      * @return currently in use codec of this buffer
      */
     QString textCodec() const
     {
         return m_textCodec;
     }
 
     /**
      * Generate byte order mark on save.
      * Loading might overwrite this setting, if there is a BOM found inside the file.
      * @param generateByteOrderMark should BOM be generated?
      */
     void setGenerateByteOrderMark(bool generateByteOrderMark)
     {
         m_generateByteOrderMark = generateByteOrderMark;
     }
 
     /**
      * Generate byte order mark on save?
      * @return should BOM be generated?
      */
     bool generateByteOrderMark() const
     {
         return m_generateByteOrderMark;
     }
 
     /**
      * Set end of line mode for this buffer, not allowed to be set to unknown.
      * Loading might overwrite this setting, if there is a eol found inside the file.
      * @param endOfLineMode new eol mode
      */
     void setEndOfLineMode(EndOfLineMode endOfLineMode)
     {
         Q_ASSERT(endOfLineMode != eolUnknown);
         m_endOfLineMode = endOfLineMode;
     }
 
     /**
      * Get end of line mode
      * @return end of line mode
      */
     EndOfLineMode endOfLineMode() const
     {
         return m_endOfLineMode;
     }
 
     /**
      * Set line length limit
      * @param lineLengthLimit new line length limit
      */
     void setLineLengthLimit(int lineLengthLimit)
     {
         m_lineLengthLimit = lineLengthLimit;
     }
 
     /**
      * Load the given file. This will first clear the buffer and then load the file.
      * Even on error during loading the buffer will still be cleared.
      * Before calling this, setTextCodec must have been used to set codec!
      * @param filename file to open
      * @param encodingErrors were there problems occurred while decoding the file?
      * @param tooLongLinesWrapped were too long lines found and wrapped?
      * @param longestLineLoaded the longest line in the file (before wrapping)
      * @param enforceTextCodec enforce to use only the set text codec
      * @return success, the file got loaded, perhaps with encoding errors
      * Virtual, can be overwritten.
      */
     virtual bool load(const QString &filename, bool &encodingErrors, bool &tooLongLinesWrapped, int &longestLineLoaded, bool enforceTextCodec);
 
     /**
      * Save the current buffer content to the given file.
      * Before calling this, setTextCodec and setFallbackTextCodec must have been used to set codec!
      * @param filename file to save
      * @return success
      * Virtual, can be overwritten.
      */
     virtual bool save(const QString &filename);
 
     /**
      * Lines currently stored in this buffer.
      * This is never 0, even clear will let one empty line remain.
      */
     int lines() const
     {
         Q_ASSERT(m_lines > 0);
         return m_lines;
     }
 
     /**
      * Revision of this buffer. Is set to 0 on construction, clear() (load will trigger clear()).
      * Is incremented on each change to the buffer.
      * @return current revision
      */
     qint64 revision() const
     {
         return m_revision;
     }
 
     /**
      * Retrieve a text line.
      * @param line wanted line number
      * @return text line
      */
     TextLine line(int line) const;
 
     /**
      * Transfer all non text attributes for the given line from the given text line to the one in the buffer.
      * @param line line number to set attributes
      * @param textLine line reference to get attributes from
      */
     void setLineMetaData(int line, const TextLine &textLine);
 
     /**
      * Retrieve length for @p line
      * @param line wanted line number
      * @return length of the line
      */
     int lineLength(int line) const
     {
         // get block, this will assert on invalid line
         int blockIndex = blockForLine(line);
 
         // get line length
         return m_blocks.at(blockIndex)->lineLength(line);
     }
 
     /**
      * Retrieve offset in text for the given cursor position
      */
     int cursorToOffset(KTextEditor::Cursor c) const;
 
     /**
      * Retrieve cursor in text for the given offset
      */
     KTextEditor::Cursor offsetToCursor(int offset) const;
 
     /**
      * Retrieve text of complete buffer.
      * @return text for this buffer, lines separated by '\n'
      */
     QString text() const;
 
     /**
      * Start an editing transaction, the wrapLine/unwrapLine/insertText and removeText functions
      * are only allowed to be called inside a editing transaction.
      * Editing transactions can stack. The number of startEdit and endEdit calls must match.
      * @return returns true, if no transaction was already running
      * Virtual, can be overwritten.
      */
     virtual bool startEditing();
 
     /**
      * Finish an editing transaction. Only allowed to be called if editing transaction is started.
      * @return returns true, if this finished last running transaction
      * Virtual, can be overwritten.
      */
     virtual bool finishEditing();
 
     /**
      * Query the number of editing transactions running atm.
      * @return number of running transactions
      */
     int editingTransactions() const
     {
         return m_editingTransactions;
     }
 
     /**
      * Query the revision of this buffer before the ongoing editing transactions.
      * @return revision of buffer before current editing transaction altered it
      */
     qint64 editingLastRevision() const
     {
         return m_editingLastRevision;
     }
 
     /**
      * Query the number of lines of this buffer before the ongoing editing transactions.
      * @return number of lines of buffer before current editing transaction altered it
      */
     int editingLastLines() const
     {
         return m_editingLastLines;
     }
 
     /**
      * Query information from the last editing transaction: was the content of the buffer changed?
      * This is checked by comparing the editingLastRevision() with the current revision().
      * @return content of buffer was changed in last transaction?
      */
     bool editingChangedBuffer() const
     {
         return editingLastRevision() != revision();
     }
 
     /**
      * Query information from the last editing transaction: was the number of lines of the buffer changed?
      * This is checked by comparing the editingLastLines() with the current lines().
      * @return content of buffer was changed in last transaction?
      */
     bool editingChangedNumberOfLines() const
     {
         return editingLastLines() != lines();
     }
 
     /**
      * Get minimal line number changed by last editing transaction
      * @return maximal line number changed by last editing transaction, or -1, if none changed
      */
     int editingMinimalLineChanged() const
     {
         return m_editingMinimalLineChanged;
     }
 
     /**
      * Get maximal line number changed by last editing transaction
      * @return maximal line number changed by last editing transaction, or -1, if none changed
      */
     int editingMaximalLineChanged() const
     {
         return m_editingMaximalLineChanged;
     }
 
     /**
      * Wrap line at given cursor position.
      * @param position line/column as cursor where to wrap
      * Virtual, can be overwritten.
      */
     virtual void wrapLine(const KTextEditor::Cursor position);
 
     /**
      * Unwrap given line.
      * @param line line to unwrap
      * Virtual, can be overwritten.
      */
     virtual void unwrapLine(int line);
 
     /**
      * Insert text at given cursor position. Does nothing if text is empty, beside some consistency checks.
      * @param position position where to insert text
      * @param text text to insert
      * Virtual, can be overwritten.
      */
     virtual void insertText(const KTextEditor::Cursor position, const QString &text);
 
     /**
      * Remove text at given range. Does nothing if range is empty, beside some consistency checks.
      * @param range range of text to remove, must be on one line only.
      * Virtual, can be overwritten.
      */
     virtual void removeText(KTextEditor::Range range);
 
     /**
      * TextHistory of this buffer
      * @return text history for this buffer
      */
     TextHistory &history()
     {
         return m_history;
     }
 
 Q_SIGNALS:
     /**
      * Buffer got cleared. This is emitted when constructor or load have called clear() internally,
      * or when the user of the buffer has called clear() itself.
      */
     void cleared();
 
     /**
      * Buffer loaded successfully a file
      * @param filename file which was loaded
      * @param encodingErrors were there problems occurred while decoding the file?
      */
     void loaded(const QString &filename, bool encodingErrors);
 
     /**
      * Buffer saved successfully a file
      * @param filename file which was saved
      */
     void saved(const QString &filename);
 
 private:
     /**
      * Save result which indicates an abstract reason why the operation has
      * failed
      */
     enum class SaveResult { Failed = 0, MissingPermissions, Success };
 
     /**
      * Find block containing given line.
      * @param line we want to find block for this line
      * @return index of found block
      */
     int blockForLine(int line) const;
     // exported for movingrange_test
 
     /**
      * Fix start lines of all blocks after the given one
      * @param startBlock index of block from which we start to fix
      */
     KTEXTEDITOR_NO_EXPORT
     void fixStartLines(int startBlock);
 
     /**
      * Balance the given block. Look if it is too small or too large.
      * @param index block to balance
      */
     KTEXTEDITOR_NO_EXPORT
     void balanceBlock(int index);
 
     /**
      * A range changed, notify the views, in case of attributes or feedback.
      * @param view which view is affected? nullptr for all views
      * @param lineRange line range that the change spans
      * @param needsRepaint do we need to trigger repaints? e.g. if ranges with attributes change
      */
     KTEXTEDITOR_NO_EXPORT
     void notifyAboutRangeChange(KTextEditor::View *view, KTextEditor::LineRange lineRange, bool needsRepaint);
 
     /**
      * Mark all modified lines as lines saved on disk (modified line system).
      */
     KTEXTEDITOR_NO_EXPORT
     void markModifiedLinesAsSaved();
 
     /**
      * Save the current buffer content to the given already opened device
      *
      * @param filename path name for display/debugging purposes
      * @param saveFile open device to write the buffer to
      */
     KTEXTEDITOR_NO_EXPORT
     bool saveBuffer(const QString &filename, KCompressionDevice &saveFile);
 
     /**
      * Attempt to save the buffer content in the given filename location using
      * current privileges.
      */
     KTEXTEDITOR_NO_EXPORT
     SaveResult saveBufferUnprivileged(const QString &filename);
 
     /**
      * Attempt to save the buffer content in the given filename location using
      * escalated privileges.
      */
     KTEXTEDITOR_NO_EXPORT
     bool saveBufferEscalated(const QString &filename);
 
 public:
     /**
      * Gets the document to which this buffer is bound.
      * \return a pointer to the document
      */
     KTextEditor::DocumentPrivate *document() const
     {
         return m_document;
     }
 
     /**
      * Debug output, print whole buffer content with line numbers and line length
      * @param title title for this output
      */
     void debugPrint(const QString &title) const;
 
     /**
      * Return the ranges which affect the given line.
      * @param line line to look at
      * @param view only return ranges associated with given view
      * @param rangesWithAttributeOnly only return ranges which have a attribute set
      * @return list of ranges affecting this line
      */
     QList<TextRange *> rangesForLine(int line, KTextEditor::View *view, bool rangesWithAttributeOnly) const
     {
         // get block, this will assert on invalid line
         const int blockIndex = blockForLine(line);
         return m_blocks.at(blockIndex)->rangesForLine(line, view, rangesWithAttributeOnly);
     }
 
     void rangesForLine(int line, KTextEditor::View *view, bool rangesWithAttributeOnly, QList<TextRange *> &outRanges) const
     {
         // get block, this will assert on invalid line
         const int blockIndex = blockForLine(line);
         return m_blocks.at(blockIndex)->rangesForLine(line, view, rangesWithAttributeOnly, outRanges);
     }
 
     /**
      * Check if the given range pointer is still valid.
      * @return range pointer still belongs to range for this buffer
      */
     bool rangePointerValid(TextRange *range) const
     {
         return m_ranges.contains(range);
     }
 
     /**
      * Invalidate all ranges in this buffer.
      */
     void invalidateRanges();
 
     //
     // checksum handling
     //
 public:
     /**
      * Checksum of the document on disk, set either through file loading
      * in openFile() or in KTextEditor::DocumentPrivate::saveFile()
      * @return git compatible sha1 checksum for this document
      */
     const QByteArray &digest() const;
 
     /**
      * Set the checksum of this buffer. Make sure this checksum is up-to-date
      * when reading digest().
      * @param checksum git compatible sha1 digest for the document on disk
      */
     void setDigest(const QByteArray &checksum);
 
 private:
     QByteArray m_digest;
 
 private:
     /**
      * parent document
      */
     KTextEditor::DocumentPrivate *m_document;
 
     /**
      * text history
      */
     TextHistory m_history;
 
     /**
      * List of blocks which contain the lines of this buffer
      */
     std::vector<TextBlock *> m_blocks;
 
     /**
      * Number of lines in buffer
      */
     int m_lines;
 
     /**
      * Revision of the buffer.
      */
     qint64 m_revision;
 
     /**
      * Current number of running edit transactions
      */
     int m_editingTransactions;
 
     /**
      * Revision remembered at start of current editing transaction
      */
     qint64 m_editingLastRevision;
 
     /**
      * Number of lines remembered at start of current editing transaction
      */
     int m_editingLastLines;
 
     /**
      * minimal line number changed by last editing transaction
      */
     int m_editingMinimalLineChanged;
 
     /**
      * maximal line number changed by last editing transaction
      */
     int m_editingMaximalLineChanged;
 
     /**
      * Set of invalid cursors for this whole buffer.
      * Valid cursors are inside the block the belong to.
      */
     QSet<TextCursor *> m_invalidCursors;
 
     /**
      * Set of ranges of this whole buffer.
      */
     QSet<TextRange *> m_ranges;
 
     /**
      * Encoding prober type to use
      */
     KEncodingProber::ProberType m_encodingProberType;
 
     /**
      * Fallback text codec to use
      */
     QString m_fallbackTextCodec;
 
     /**
      * Text codec to use
      */
     QString m_textCodec;
 
     /**
      * Mime-Type used for transparent compression/decompression support
      * Set by load(), reset by clear()
      */
     QString m_mimeTypeForFilterDev;
 
     /**
      * Should byte order mark be created?
      */
     bool m_generateByteOrderMark;
 
     /**
      * End of line mode, default is Unix
      */
     EndOfLineMode m_endOfLineMode;
 
     /**
      * Limit for line length, longer lines will be wrapped on load
      */
     int m_lineLengthLimit;
 
     /**
      * For unit-testing purposes only.
      */
     bool m_alwaysUseKAuthForSave;
 
     /**
      * For copying QBuffer -> QTemporaryFile while saving document in privileged mode
      */
     static const qint64 bufferLength = 4096;
 };
 
 }
 
 #endif