package aQute.bnd.properties;
import java.util.ArrayList;
import java.util.List;
import aQute.bnd.properties.Document.DelimiterInfo;
public class LineTracker {
/** The line information */
private final List<Line> fLines = new ArrayList<Line>();
/** The length of the tracked text */
private int fTextLength;
/**
* Creates a new line tracker.
*/
protected LineTracker() {}
/**
* Binary search for the line at a given offset.
*
* @param offset
* the offset whose line should be found
* @return the line of the offset
*/
private int findLine(int offset) {
if (fLines.size() == 0)
return -1;
int left = 0;
int right = fLines.size() - 1;
int mid = 0;
Line line = null;
while (left < right) {
mid = (left + right) / 2;
line = fLines.get(mid);
if (offset < line.offset) {
if (left == mid)
right = left;
else
right = mid - 1;
} else if (offset > line.offset) {
if (right == mid)
left = right;
else
left = mid + 1;
} else if (offset == line.offset) {
left = right = mid;
}
}
line = fLines.get(left);
if (line.offset > offset)
--left;
return left;
}
/**
* Returns the number of lines covered by the specified text range.
*
* @param startLine
* the line where the text range starts
* @param offset
* the start offset of the text range
* @param length
* the length of the text range
* @return the number of lines covered by this text range
* @exception BadLocationException
* if range is undefined in this tracker
*/
private int getNumberOfLines(int startLine, int offset, int length) throws BadLocationException {
if (length == 0)
return 1;
int target = offset + length;
Line l = fLines.get(startLine);
if (l.delimiter == null)
return 1;
if (l.offset + l.length > target)
return 1;
if (l.offset + l.length == target)
return 2;
return getLineNumberOfOffset(target) - startLine + 1;
}
/*
* @see org.eclipse.jface.text.ILineTracker#getLineLength(int)
*/
public final int getLineLength(int line) throws BadLocationException {
int lines = fLines.size();
if (line < 0 || line > lines)
throw new BadLocationException();
if (lines == 0 || lines == line)
return 0;
Line l = fLines.get(line);
return l.length;
}
/*
* @see org.eclipse.jface.text.ILineTracker#getLineNumberOfOffset(int)
*/
public final int getLineNumberOfOffset(int position) throws BadLocationException {
if (position < 0 || position > fTextLength)
throw new BadLocationException();
if (position == fTextLength) {
int lastLine = fLines.size() - 1;
if (lastLine < 0)
return 0;
Line l = fLines.get(lastLine);
return (l.delimiter != null ? lastLine + 1 : lastLine);
}
return findLine(position);
}
/*
* @see org.eclipse.jface.text.ILineTracker#getLineInformationOfOffset(int)
*/
public final IRegion getLineInformationOfOffset(int position) throws BadLocationException {
if (position > fTextLength)
throw new BadLocationException();
if (position == fTextLength) {
int size = fLines.size();
if (size == 0)
return new Region(0, 0);
Line l = fLines.get(size - 1);
return (l.delimiter != null ? new Line(fTextLength, 0) : new Line(fTextLength - l.length, l.length));
}
return getLineInformation(findLine(position));
}
/*
* @see org.eclipse.jface.text.ILineTracker#getLineInformation(int)
*/
public final IRegion getLineInformation(int line) throws BadLocationException {
int lines = fLines.size();
if (line < 0 || line > lines)
throw new BadLocationException();
if (lines == 0)
return new Line(0, 0);
if (line == lines) {
Line l = fLines.get(line - 1);
return new Line(l.offset + l.length, 0);
}
Line l = fLines.get(line);
return (l.delimiter != null ? new Line(l.offset, l.length - l.delimiter.length()) : l);
}
/*
* @see org.eclipse.jface.text.ILineTracker#getLineOffset(int)
*/
public final int getLineOffset(int line) throws BadLocationException {
int lines = fLines.size();
if (line < 0 || line > lines)
throw new BadLocationException();
if (lines == 0)
return 0;
if (line == lines) {
Line l = fLines.get(line - 1);
if (l.delimiter != null)
return l.offset + l.length;
throw new BadLocationException();
}
Line l = fLines.get(line);
return l.offset;
}
/*
* @see org.eclipse.jface.text.ILineTracker#getNumberOfLines()
*/
public final int getNumberOfLines() {
int lines = fLines.size();
if (lines == 0)
return 1;
Line l = fLines.get(lines - 1);
return (l.delimiter != null ? lines + 1 : lines);
}
/*
* @see org.eclipse.jface.text.ILineTracker#getNumberOfLines(int, int)
*/
public final int getNumberOfLines(int position, int length) throws BadLocationException {
if (position < 0 || position + length > fTextLength)
throw new BadLocationException();
if (length == 0) // optimization
return 1;
return getNumberOfLines(getLineNumberOfOffset(position), position, length);
}
/*
* @see
* org.eclipse.jface.text.ILineTracker#computeNumberOfLines(java.lang.String
* )
*/
public final int computeNumberOfLines(String text) {
int count = 0;
int start = 0;
DelimiterInfo delimiterInfo = nextDelimiterInfo(text, start);
while (delimiterInfo != null && delimiterInfo.delimiterIndex > -1) {
++count;
start = delimiterInfo.delimiterIndex + delimiterInfo.delimiterLength;
delimiterInfo = nextDelimiterInfo(text, start);
}
return count;
}
/*
* @see org.eclipse.jface.text.ILineTracker#getLineDelimiter(int)
*/
public final String getLineDelimiter(int line) throws BadLocationException {
int lines = fLines.size();
if (line < 0 || line > lines)
throw new BadLocationException();
if (lines == 0)
return null;
if (line == lines)
return null;
Line l = fLines.get(line);
return l.delimiter;
}
/**
* Returns the information about the first delimiter found in the given text
* starting at the given offset.
*
* @param text
* the text to be searched
* @param offset
* the offset in the given text
* @return the information of the first found delimiter or <code>null</code>
*/
protected DelimiterInfo nextDelimiterInfo(String text, int offset) {
char ch;
int length = text.length();
for (int i = offset; i < length; i++) {
ch = text.charAt(i);
if (ch == '\r') {
if (i + 1 < length) {
if (text.charAt(i + 1) == '\n') {
DelimiterInfo fDelimiterInfo = new DelimiterInfo();
fDelimiterInfo.delimiter = Document.DELIMITERS[2];
fDelimiterInfo.delimiterIndex = i;
fDelimiterInfo.delimiterLength = 2;
return fDelimiterInfo;
}
}
DelimiterInfo fDelimiterInfo = new DelimiterInfo();
fDelimiterInfo.delimiter = Document.DELIMITERS[0];
fDelimiterInfo.delimiterIndex = i;
fDelimiterInfo.delimiterLength = 1;
return fDelimiterInfo;
} else if (ch == '\n') {
DelimiterInfo fDelimiterInfo = new DelimiterInfo();
fDelimiterInfo.delimiter = Document.DELIMITERS[1];
fDelimiterInfo.delimiterIndex = i;
fDelimiterInfo.delimiterLength = 1;
return fDelimiterInfo;
}
}
return null;
}
/**
* Creates the line structure for the given text. Newly created lines are
* inserted into the line structure starting at the given position. Returns
* the number of newly created lines.
*
* @param text
* the text for which to create a line structure
* @param insertPosition
* the position at which the newly created lines are inserted
* into the tracker's line structure
* @param offset
* the offset of all newly created lines
* @return the number of newly created lines
*/
private int createLines(String text, int insertPosition, int offset) {
int count = 0;
int start = 0;
DelimiterInfo delimiterInfo = nextDelimiterInfo(text, 0);
while (delimiterInfo != null && delimiterInfo.delimiterIndex > -1) {
int index = delimiterInfo.delimiterIndex + (delimiterInfo.delimiterLength - 1);
if (insertPosition + count >= fLines.size())
fLines.add(new Line(offset + start, offset + index, delimiterInfo.delimiter));
else
fLines.add(insertPosition + count, new Line(offset + start, offset + index, delimiterInfo.delimiter));
++count;
start = index + 1;
delimiterInfo = nextDelimiterInfo(text, start);
}
if (start < text.length()) {
if (insertPosition + count < fLines.size()) {
// there is a line below the current
Line l = fLines.get(insertPosition + count);
int delta = text.length() - start;
l.offset -= delta;
l.length += delta;
} else {
fLines.add(new Line(offset + start, offset + text.length() - 1, null));
++count;
}
}
return count;
}
/*
* @see org.eclipse.jface.text.ILineTracker#replace(int, int,
* java.lang.String)
*/
public final void replace(@SuppressWarnings("unused") int position, @SuppressWarnings("unused") int length, @SuppressWarnings("unused") String text) throws BadLocationException {
throw new UnsupportedOperationException();
}
/*
* @see org.eclipse.jface.text.ILineTracker#set(java.lang.String)
*/
public final void set(String text) {
fLines.clear();
if (text != null) {
fTextLength = text.length();
createLines(text, 0, 0);
}
}
/**
* Returns the internal data structure, a {@link List} of {@link Line}s.
* Used only by {@link TreeLineTracker#TreeLineTracker(ListLineTracker)}.
*
* @return the internal list of lines.
*/
final List<Line> getLines() {
return fLines;
}
}