/*
* FirstLine.java
* :tabSize=4:indentSize=4:noTabs=false:
* :folding=explicit:collapseFolds=1:
*
* Copyright (C) 2005 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;
import org.gjt.sp.jedit.Debug;
import org.gjt.sp.util.Log;
/**
* This Anchor is the first visible line of the textarea.
*
* @author Slava Pestov
* @version $Id: FirstLine.java 23224 2013-09-30 20:51:42Z shlomy $
*/
class FirstLine extends Anchor
{
// scrollLine + skew = vertical scroll bar position
/**
* The skew is the scroll count from the beginning of the line.
* Used with soft wrap.
*/
private int skew;
private int preContentRemovedNumLines;
//{{{ FirstLine constructor
FirstLine(DisplayManager displayManager,
TextArea textArea)
{
super(displayManager,textArea);
} //}}}
@Override
void preContentInserted(int startLine, int numLines)
{
int scrollLines = 0;
int physicalLine = startLine;
int currentPhysicalLine = getPhysicalLine();
int numLinesVisible = 0;
for(int i = 0;
physicalLine < currentPhysicalLine;
i++, physicalLine++)
{
if(getDisplayManager().isLineVisible(physicalLine))
{
scrollLines += getDisplayManager().getScreenLineCount(physicalLine);
}
if(i < numLines)
numLinesVisible++;
}
preContentInsertedScrollLines = scrollLines;
}
//{{{ contentInserted() method
/**
* Some content is inserted.
*
* @param startLine the start of the insert
* @param numLines the number of inserted lines
*/
void contentInserted(int startLine, int numLines)
{
if(Debug.SCROLL_DEBUG)
Log.log(Log.DEBUG,this,"contentInserted() before:" + this);
int currentPhysicalLine = getPhysicalLine();
// The Anchor is changed only if the content was inserted before
if(startLine == currentPhysicalLine)
setCallChanged(true);
else if(startLine < currentPhysicalLine)
{
int scrollLines = 0;
int physicalLine = startLine;
int endLine = currentPhysicalLine + numLines;
int numLinesVisible = 0;
for(int i = 0;physicalLine < endLine; physicalLine++, i++)
{
if(getDisplayManager().isLineVisible(physicalLine))
{
scrollLines += getDisplayManager().getScreenLineCount(physicalLine);
}
if(i < numLines)
numLinesVisible++;
}
movePhysicalLine(numLinesVisible);
moveScrollLine(scrollLines - preContentInsertedScrollLines);
}
if(Debug.SCROLL_DEBUG)
Log.log(Log.DEBUG,this,"contentInserted() after:" + this);
if(Debug.SCROLL_VERIFY)
scrollVerify();
} //}}}
@Override
void preContentRemoved(int startLine, int offset, int numLines)
{
int scrollLines = 0;
int physicalLine = startLine;
int currentPhysicalLine = getPhysicalLine();
int numLinesVisible = 0;
for(int i = 0;
physicalLine < currentPhysicalLine;
i++, physicalLine++)
{
if(getDisplayManager().isLineVisible(physicalLine))
{
scrollLines += getDisplayManager().getScreenLineCount(physicalLine);
}
if(i < numLines)
numLinesVisible++;
}
preContentRemovedScrollLines = scrollLines;
preContentRemovedNumLines = numLinesVisible;
}
//{{{ contentRemoved() method
/**
* Method called before a content is removed from a buffer.
*
* @param startLine the first line of the removed content
* @param startOffset the offset in the start line
* @param numLines the number of removed lines
*/
void contentRemoved(int startLine, int startOffset, int numLines)
{
if(Debug.SCROLL_DEBUG)
Log.log(Log.DEBUG,this,"contentRemoved() before:" + this);
// The removed content starts before the Anchor, we need to pull the anchor up
int currentPhysicalLine = getPhysicalLine();
if(startLine == currentPhysicalLine)
setCallChanged(true);
else if(startLine < currentPhysicalLine)
{
int scrollLines = 0;
int physicalLine = startLine;
int endLine = currentPhysicalLine - numLines;
for(;physicalLine < endLine; physicalLine++)
{
if(getDisplayManager().isLineVisible(physicalLine))
{
scrollLines += getDisplayManager().getScreenLineCount(physicalLine);
}
}
movePhysicalLine(-preContentRemovedNumLines);
moveScrollLine(scrollLines - preContentRemovedScrollLines);
}
if(Debug.SCROLL_DEBUG)
Log.log(Log.DEBUG,this,"contentRemoved() after:" + this);
if(Debug.SCROLL_VERIFY)
scrollVerify();
} //}}}
//{{{ changed() method
@Override
public void changed()
{
//{{{ Debug code
if(Debug.SCROLL_DEBUG)
{
Log.log(Log.DEBUG,this,"changed() before: "
+ getPhysicalLine() + ':' + getScrollLine()
+ ':' + getSkew());
} //}}}
if(Debug.SCROLL_VERIFY)
scrollVerify();
ensurePhysicalLineIsVisible();
int currentPhysicalLine = getPhysicalLine();
int screenLines = getDisplayManager().getScreenLineCount(currentPhysicalLine);
if(getSkew() >= screenLines)
setSkew(screenLines - 1);
//{{{ Debug code
if(Debug.SCROLL_VERIFY)
scrollVerify();
if(Debug.SCROLL_DEBUG)
{
Log.log(Log.DEBUG,this,"changed() after: "
+ getPhysicalLine() + ':' + getScrollLine()
+ ':' + getSkew());
} //}}}
} //}}}
private void scrollVerify()
{
System.err.println("SCROLL_VERIFY");
int verifyScrollLine = 0;
int currentPhysicalLine = getPhysicalLine();
for(int i = 0, n = getDisplayManager().getBuffer().getLineCount(); i < n && i < currentPhysicalLine; i++)
{
if(getDisplayManager().isLineVisible(i))
verifyScrollLine += getDisplayManager().getScreenLineCount(i);
}
int scrollLine = getScrollLine();
if(verifyScrollLine != scrollLine)
{
RuntimeException ex = new RuntimeException("ScrollLine is " + scrollLine + " but should be " + verifyScrollLine + " diff = " + (verifyScrollLine - scrollLine));
Log.log(Log.ERROR,this,ex);
}
}
//{{{ reset() method
@Override
public void reset()
{
if(Debug.SCROLL_DEBUG)
Log.log(Log.DEBUG,this,"reset()");
int currentPhysicalLine = getPhysicalLine();
int physicalLine = getDisplayManager().getFirstVisibleLine();
int scrollLine = 0;
while(physicalLine != -1)
{
if(physicalLine >= currentPhysicalLine)
break;
scrollLine += getDisplayManager().getScreenLineCount(physicalLine);
int nextLine = getDisplayManager().getNextVisibleLine(physicalLine);
if(nextLine == -1)
break;
else
physicalLine = nextLine;
}
setPhysicalLine(physicalLine);
setScrollLine(scrollLine);
int screenLines = getDisplayManager().getScreenLineCount(physicalLine);
if(getSkew() >= screenLines)
setSkew(screenLines - 1);
getTextArea().updateScrollBar();
} //}}}
//{{{ physDown() method
// scroll down by physical line amount
void physDown(int amount, int screenAmount)
{
int currentPhysicalLine = getPhysicalLine();
int currentScrollLine = getScrollLine();
if(Debug.SCROLL_DEBUG)
{
Log.log(Log.DEBUG,this,"physDown() start: "
+ currentPhysicalLine + ':' + currentScrollLine);
}
setSkew(0);
if(!getDisplayManager().isLineVisible(currentPhysicalLine))
{
int lastVisibleLine = getDisplayManager().getLastVisibleLine();
if(currentPhysicalLine > lastVisibleLine)
setPhysicalLine(lastVisibleLine);
else
{
int nextPhysicalLine = getDisplayManager().getNextVisibleLine(currentPhysicalLine);
assert nextPhysicalLine > 0;
amount -= nextPhysicalLine - currentPhysicalLine;
moveScrollLine(getDisplayManager().getScreenLineCount(currentPhysicalLine));
setPhysicalLine(nextPhysicalLine);
}
}
currentPhysicalLine = getPhysicalLine();
int scrollLines = 0;
for(;;)
{
int nextPhysicalLine = getDisplayManager().getNextVisibleLine(currentPhysicalLine);
if(nextPhysicalLine == -1)
break;
else if(nextPhysicalLine > currentPhysicalLine + amount)
break;
else
{
scrollLines += getDisplayManager().getScreenLineCount(currentPhysicalLine);
amount -= nextPhysicalLine - currentPhysicalLine;
currentPhysicalLine = nextPhysicalLine;
}
}
setPhysicalLine(currentPhysicalLine);
moveScrollLine(scrollLines);
if(Debug.SCROLL_DEBUG)
{
Log.log(Log.DEBUG,this,"physDown() end: "
+ getPhysicalLine() + ':' + getScrollLine());
}
// JEditTextArea.scrollTo() needs this to simplify
// its code
if(screenAmount < 0)
scrollUp(-screenAmount);
else if(screenAmount > 0)
scrollDown(screenAmount);
} //}}}
//{{{ physUp() method
// scroll up by physical line amount
void physUp(int amount, int screenAmount)
{
if(Debug.SCROLL_DEBUG)
{
Log.log(Log.DEBUG,this,"physUp() start: "
+getPhysicalLine()+ ':' + getScrollLine());
}
setSkew(0);
int currentPhysicalLine = getPhysicalLine();
if(!getDisplayManager().isLineVisible(currentPhysicalLine))
{
int firstVisibleLine = getDisplayManager().getFirstVisibleLine();
if(currentPhysicalLine < firstVisibleLine)
setPhysicalLine(firstVisibleLine);
else
{
int prevPhysicalLine = getDisplayManager().getPrevVisibleLine(currentPhysicalLine);
amount -= currentPhysicalLine - prevPhysicalLine;
}
}
currentPhysicalLine = getPhysicalLine();
int scrollLines = 0;
for(;;)
{
int prevPhysicalLine = getDisplayManager().getPrevVisibleLine(currentPhysicalLine);
if(prevPhysicalLine == -1)
break;
else if(prevPhysicalLine < currentPhysicalLine - amount)
break;
else
{
scrollLines -= getDisplayManager().getScreenLineCount(prevPhysicalLine);
amount -= currentPhysicalLine - prevPhysicalLine;
currentPhysicalLine = prevPhysicalLine;
}
}
setPhysicalLine(currentPhysicalLine);
moveScrollLine(scrollLines);
if(Debug.SCROLL_DEBUG)
{
Log.log(Log.DEBUG,this,"physUp() end: "
+getPhysicalLine()+ ':' + getScrollLine());
}
// JEditTextArea.scrollTo() needs this to simplify
// its code
if(screenAmount < 0)
scrollUp(-screenAmount);
else if(screenAmount > 0)
scrollDown(screenAmount);
} //}}}
//{{{ scrollDown() method
// scroll down by screen line amount
void scrollDown(int amount)
{
if(Debug.SCROLL_DEBUG)
Log.log(Log.DEBUG,this,"scrollDown()");
ensurePhysicalLineIsVisible();
amount += getSkew();
setSkew(0);
int physicalLine = getPhysicalLine();
int screenLinesSum = 0;
while(amount > 0)
{
int screenLines = getDisplayManager().getScreenLineCount(physicalLine);
if(amount < screenLines)
{
setSkew(amount);
break;
}
else
{
int nextLine = getDisplayManager().getNextVisibleLine(physicalLine);
if(nextLine == -1)
break;
boolean visible = getDisplayManager().isLineVisible(physicalLine);
physicalLine = nextLine;
if(visible)
{
amount -= screenLines;
screenLinesSum += screenLines;
}
}
}
setPhysicalLine(physicalLine);
moveScrollLine(screenLinesSum);
} //}}}
//{{{ scrollUp() method
// scroll up by screen line amount
void scrollUp(int amount)
{
if(Debug.SCROLL_DEBUG)
Log.log(Log.DEBUG,this,"scrollUp() before:" + this);
ensurePhysicalLineIsVisible();
if(amount <= getSkew())
{
// the amount is less than the skew, so we stay in the same like, just going
// upper
setSkew(getSkew() - amount);
}
else
{
// moving to the first screen line of the current physical line
amount -= getSkew();
setSkew(0);
int physicalLine = getPhysicalLine();
int screenLinesSum = 0;
while(amount > 0)
{
int prevLine = getDisplayManager().getPrevVisibleLine(physicalLine);
if(prevLine == -1)
break;
// moving to the previous visible physical line
physicalLine = prevLine;
int screenLines = getDisplayManager().getScreenLineCount(physicalLine);
screenLinesSum -= screenLines;
if(amount < screenLines)
{
setSkew(screenLines - amount);
break;
}
else
{
amount -= screenLines;
}
}
setPhysicalLine(physicalLine);
moveScrollLine(screenLinesSum);
}
if(Debug.SCROLL_DEBUG)
Log.log(Log.DEBUG,this,"scrollUp() after:" + this);
} //}}}
//{{{ ensurePhysicalLineIsVisible() method
void ensurePhysicalLineIsVisible()
{
int physicalLine = getPhysicalLine();
if(!getDisplayManager().isLineVisible(physicalLine))
{
if(physicalLine > getDisplayManager().getLastVisibleLine())
{
setPhysicalLine(getDisplayManager().getLastVisibleLine());
setScrollLine(getDisplayManager().getScrollLineCount() - 1);
}
else if(physicalLine < getDisplayManager().getFirstVisibleLine())
{
setPhysicalLine(getDisplayManager().getFirstVisibleLine());
setScrollLine(0);
}
else
{
int nextLine = getDisplayManager().getNextVisibleLine(physicalLine);
assert nextLine > 0;
int screenLineCount = 0;
screenLineCount = getDisplayManager().getScreenLineCount(nextLine);
setPhysicalLine(nextLine);
moveScrollLine(screenLineCount);
}
}
} //}}}
//{{{ toString() method
@Override
public String toString()
{
return "FirstLine["+ getPhysicalLine() + ',' + getScrollLine() + ',' + getSkew() + ']';
} //}}}
int getSkew()
{
return skew;
}
void setSkew(int skew)
{
if(this.skew != skew)
{
this.skew = skew;
setCallChanged(true);
}
}
}