/*
* ScreenLineManager.java - Manage screen line counts
* :tabSize=4:indentSize=4:noTabs=false:
* :folding=explicit:collapseFolds=1:
*
* Copyright (C) 2004 Slava Pestov
*
* 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; either version 2
* of the License, or any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
package org.gjt.sp.jedit.textarea;
//{{{ Imports
import org.gjt.sp.jedit.buffer.*;
import org.gjt.sp.jedit.Debug;
import org.gjt.sp.util.Log;
//}}}
/**
* Performs the Mapping between physical lines and screen lines.
*
* @since jEdit 4.3pre1
* @author Slava Pestov
* @version $Id: ScreenLineManager.java 22629 2012-12-29 17:06:56Z thomasmey $
*/
class ScreenLineManager
{
//{{{ ScreenLineManager constructor
ScreenLineManager(JEditBuffer buffer)
{
this.buffer = buffer;
if(!buffer.isLoading())
reset();
} //}}}
//{{{ isScreenLineCountValid() method
boolean isScreenLineCountValid(int line)
{
return screenLines[line] > 0;
} //}}}
//{{{ getScreenLineCount() method
/**
* Returns how many screen lines contains the given physical line.
* It can be greater than 1 when using soft wrap
*
* @param line the physical line
* @return the screen line count
*/
int getScreenLineCount(int line)
{
assert isScreenLineCountValid(line);
return screenLines[line];
} //}}}
//{{{ setScreenLineCount() method
/**
* Sets the number of screen lines that the specified physical line
* is split into.
* @param line the physical line number
* @param count the line count (1 if no wrap)
*/
void setScreenLineCount(int line, int count)
{
assert count > 0 : "New line count is bogus!";
if(count > Short.MAX_VALUE)
{
// limitations...
count = Short.MAX_VALUE;
Log.log(Log.ERROR,this,new Exception("Max screen line count hit!"));
}
if(Debug.SCREEN_LINES_DEBUG)
Log.log(Log.DEBUG,this,new Exception("setScreenLineCount(" + line + ',' + count + ')'));
screenLines[line] = (char)count;
} //}}}
//{{{ invalidateScreenLineCounts() method
void invalidateScreenLineCounts()
{
for(int i = 0, lineCount = buffer.getLineCount(); i < lineCount; i++)
invalidateScreenLineCount(i);
} //}}}
//{{{ invalidateScreenLineCounts() method
private void invalidateScreenLineCount(int physicalLineNo)
{
screenLines[physicalLineNo] = 0;
} //}}}
//{{{ reset() method
void reset()
{
screenLines = new char[buffer.getLineCount()];
} //}}}
//{{{ contentInserted() method
public void contentInserted(int startLine, int numLines)
{
int endLine = startLine + numLines;
invalidateScreenLineCount(startLine);
int lineCount = buffer.getLineCount();
if(numLines > 0)
{
if(screenLines.length <= lineCount)
{
char[] screenLinesN = new char[((lineCount + 1) << 1)];
System.arraycopy(screenLines,0,screenLinesN,0,
screenLines.length);
screenLines = screenLinesN;
}
System.arraycopy(screenLines,startLine,screenLines,
endLine,lineCount - endLine);
for(int i = 0; i < numLines; i++)
screenLines[startLine + i] = 0;
}
} //}}}
//{{{ contentRemoved() method
public void contentRemoved(int startLine, int numLines)
{
int endLine = startLine + numLines;
invalidateScreenLineCount(startLine);
if(numLines > 0 && endLine != screenLines.length)
{
System.arraycopy(screenLines,endLine + 1,screenLines,
startLine + 1,screenLines.length - endLine - 1);
}
} //}}}
//{{{ Private members
private final JEditBuffer buffer;
/** This array contains the screen line count for each physical line.
* screenLines[physicalLineNo] == 0 -> invalid entry - No. of screen lines not calculated yet
* screenLines[physicalLineNo] > 0 -> valid entry - No. of screen lines already calculated
*/
private char[] screenLines;
//}}}
}