/***************************************************************************
kbufferlayout.h - description
-------------------
begin : Thu Jun 12 2003
copyright : (C) 2003 by Friedrich W. H. Kossebau
email : Friedrich.W.H@Kossebau.de
***************************************************************************/
/***************************************************************************
* *
* This library is free software; you can redistribute it and/or *
* modify it under the terms of the GNU Library General Public *
* License version 2 as published by the Free Software Foundation. *
* *
***************************************************************************/
#ifndef KHE_KBUFFERLAYOUT_H
#define KHE_KBUFFERLAYOUT_H
// lib specific
#include "kcoordrange.h"
#include "ksection.h"
namespace KHE {
/**@short the logical layout of a plain buffer view
*
* Given the values for
* * length of the buffer,
* * number of bytes per line,
* * a possible (relative) offset in the display, and
* * the number of lines per page jump
* the following values are calculated:
* * starting line of display,
* * starting position in this line,
* * final line of display,
* * final position in this line, and
* * the total number of lines (is final line +1 or 0)
*
* This layout sees the buffer as a continous stream of byte,
* thus uses each line after the start from the begin to the end.
*
* If the buffer is empty the end coord will be set one pos left to the start coord
* to easen the cursor handling.
*
*@author Friedrich W. H. Kossebau
*/
class TDEBufferLayout
{
public:
TDEBufferLayout( int NoBpL, int SO, int L );
//TDEBufferLayout();
~TDEBufferLayout();
public: // given values
/** */
int startOffset() const;
/** returns number of bytes per line */
int noOfBytesPerLine() const;
/** returns the length of the displayed data (equals Buffer->size()) */
int length() const;
/** returns number of lines per visual page */
int noOfLinesPerPage() const;
public: // calculated values
int startLine() const;
int startPos() const;
/** returns the coord of the start */
TDEBufferCoord start() const;
int finalLine() const;
int finalPos() const;
/** returns the coord of the end */
TDEBufferCoord final() const;
/** tells how much lines this layout needs (incl. blank leading lines due to StartOffset) */
int noOfLines() const;
public: // value calculation service
/** calculates the index of the coord
* If the coord is before the first coord the first index is returned,
* if the coord is behind the last coord the last index is returned
*/
int indexAtCCoord( const TDEBufferCoord &C ) const;
/** calculates the index of the first pos in line.
* If the line is below the first line the first index is returned,
* if the line is above the last line the last index is returned
*/
int indexAtCLineStart( int L ) const;
/** calculates the index of last pos in line
* If the line is below the first line the first index is returned,
* if the line is above the last line the last index is returned
*/
int indexAtCLineEnd( int L ) const;
/** calculates the line in which index is found
* If the index is below the first index the first line is returned,
* if the index is above the last index the last line is returned
*/
int lineAtCIndex( int Index ) const;
/** calculates the coord in which index is found
* If the index is below the first index the first coord is returned,
* if the index is above the last index the last coord is returned
*/
TDEBufferCoord coordOfCIndex( int Index ) const;
/** calculates the index of coord. if coord is invalid the behaviour is undefinded */
int indexAtCoord( const TDEBufferCoord &C ) const;
/** calculates the index of the first pos in line. if line is invalid the behaviour is undefinded */
int indexAtLineStart( int L ) const;
/** calculates the index of last pos in line. if line is invalid the behaviour is undefinded */
int indexAtLineEnd( int L ) const;
/** calculates the line in which index is found. if index is invalid the behaviour is undefinded */
int lineAtIndex( int Index ) const;
/** calculates the coord in which index is found. if index is invalid the behaviour is undefinded */
TDEBufferCoord coordOfIndex( int Index ) const;
/** returns the used positions in line */
KSection positions( int Line ) const;
/** returns the first Pos in line. if line is invalid the behaviour is undefinded */
int firstPos( int Line ) const;
/** returns the last Pos in line. if line is invalid the behaviour is undefinded */
int lastPos( int Line ) const;
/** returns the valid Pos or the first Pos in line. if coord is invalid the behaviour is undefinded */
int firstPos( const TDEBufferCoord &C ) const;
/** returns the valid Pos or the last Pos in line. if coord is invalid the behaviour is undefinded */
int lastPos( const TDEBufferCoord &C ) const;
/** returns true if the line has content */
bool hasContent( int Line ) const;
/** returns true if the coord is the first in it's line. if coord is invalid the behaviour is undefinded */
bool atLineStart( const TDEBufferCoord &C ) const;
/** returns true if the coord is the last in it's line. if coord is invalid the behaviour is undefinded */
bool atLineEnd( const TDEBufferCoord &C ) const;
/** returns the index if valid or the nearest valid index */
int correctIndex( int I ) const;
/** returns the coord if valid or the nearest valid coord */
TDEBufferCoord correctCoord( const TDEBufferCoord &C ) const;
public: // modification access; return true if changes
/** sets StartOffset, returns true if changed */
bool setStartOffset( int SO );
/** sets number of bytes per line, returns true if changed */
bool setNoOfBytesPerLine( int N );
/** sets number of lines per page */
void setNoOfLinesPerPage( int N );
/** sets length of data to display, returns true if changed */
bool setLength( int L );
protected:
/** calculates the start coord by startoffset and number of bytes per line */
void calcStart();
/** calculates the final coord by startoffset, length, and number of bytes per line */
void calcEnd();
protected:
/** how many chars per line */
int NoOfBytesPerLine;
/** starting offset of the displayed data */
int StartOffset;
/** length of the displayed buffer */
int Length;
/** number of lines that are moved by page up/down */
int NoOfLinesPerPage;
protected: // calculated values, buffered
/** coord in which the start offset is (starting with 0) */
// TDEBufferCoord Start;
/** coord in which the last byte is (starting with 0) */
// TDEBufferCoord Final;
/** */
KCoordRange ContentCoords;
};
inline int TDEBufferLayout::startOffset() const { return StartOffset; }
inline int TDEBufferLayout::noOfBytesPerLine() const { return NoOfBytesPerLine; }
inline int TDEBufferLayout::length() const { return Length; }
inline TDEBufferCoord TDEBufferLayout::final() const { return ContentCoords.end(); }
inline TDEBufferCoord TDEBufferLayout::start() const { return ContentCoords.start(); }
inline int TDEBufferLayout::startPos() const { return start().pos(); }
inline int TDEBufferLayout::finalPos() const { return final().pos(); }
inline int TDEBufferLayout::startLine() const { return start().line(); }
inline int TDEBufferLayout::finalLine() const { return final().line(); }
inline int TDEBufferLayout::noOfLinesPerPage() const { return NoOfLinesPerPage; }
inline int TDEBufferLayout::noOfLines() const { return Length==0?0:final().line()+1; }
}
#endif