/*
* Breaker.java
* Copyright (c) 2004, 2005 Torbj�rn Gannholm,
* Copyright (c) 2005 Wisconsin Court System
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2.1
* of the License, or (at your option) 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser 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.xhtmlrenderer.layout;
import org.xhtmlrenderer.css.constants.IdentValue;
import org.xhtmlrenderer.css.style.CalculatedStyle;
import org.xhtmlrenderer.render.FSFont;
/**
* A utility class that scans the text of a single inline box, looking for the
* next break point.
* @author Torbj�rn Gannholm
*/
public class Breaker {
public static void breakFirstLetter(LayoutContext c, LineBreakContext context,
int avail, CalculatedStyle style) {
FSFont font = style.getFSFont(c);
context.setEnd(getFirstLetterEnd(context.getMaster(), context.getStart()));
context.setWidth(c.getTextRenderer().getWidth(
c.getFontContext(), font, context.getCalculatedSubstring()));
if (context.getWidth() > avail) {
context.setNeedsNewLine(true);
context.setUnbreakable(true);
}
}
private static int getFirstLetterEnd(String text, int start) {
int i = start;
while (i < text.length()) {
char c = text.charAt(i);
int type = Character.getType(c);
if (type == Character.START_PUNCTUATION ||
type == Character.END_PUNCTUATION ||
type == Character.INITIAL_QUOTE_PUNCTUATION ||
type == Character.FINAL_QUOTE_PUNCTUATION ||
type == Character.OTHER_PUNCTUATION) {
i++;
} else {
break;
}
}
if (i < text.length()) {
i++;
}
return i;
}
public static void breakText(LayoutContext c,
LineBreakContext context, int avail, CalculatedStyle style) {
FSFont font = style.getFSFont(c);
IdentValue whitespace = style.getWhitespace();
// ====== handle nowrap
if (whitespace == IdentValue.NOWRAP) {
context.setEnd(context.getLast());
context.setWidth(c.getTextRenderer().getWidth(
c.getFontContext(), font, context.getCalculatedSubstring()));
return;
}
//check if we should break on the next newline
if (whitespace == IdentValue.PRE ||
whitespace == IdentValue.PRE_WRAP ||
whitespace == IdentValue.PRE_LINE) {
int n = context.getStartSubstring().indexOf(WhitespaceStripper.EOL);
if (n > -1) {
context.setEnd(context.getStart() + n + 1);
context.setWidth(c.getTextRenderer().getWidth(
c.getFontContext(), font, context.getCalculatedSubstring()));
context.setNeedsNewLine(true);
context.setEndsOnNL(true);
} else if (whitespace == IdentValue.PRE) {
context.setEnd(context.getLast());
context.setWidth(c.getTextRenderer().getWidth(
c.getFontContext(), font, context.getCalculatedSubstring()));
}
}
//check if we may wrap
if (whitespace == IdentValue.PRE ||
(context.isNeedsNewLine() && context.getWidth() <= avail)) {
return;
}
context.setEndsOnNL(false);
String currentString = context.getStartSubstring();
int left = 0;
int right = getStrRight(currentString, left + 1);
int lastWrap = 0;
int graphicsLength = 0;
int lastGraphicsLength = 0;
while (right > 0 && graphicsLength <= avail) {
lastGraphicsLength = graphicsLength;
graphicsLength += c.getTextRenderer().getWidth(
c.getFontContext(), font, currentString.substring(left, right));
lastWrap = left;
left = right;
right = getStrRight(currentString, left + 1);
}
if (graphicsLength <= avail) {
//try for the last bit too!
lastWrap = left;
lastGraphicsLength = graphicsLength;
graphicsLength += c.getTextRenderer().getWidth(
c.getFontContext(), font, currentString.substring(left));
}
if (graphicsLength <= avail) {
context.setWidth(graphicsLength);
context.setEnd(context.getMaster().length());
//It fit!
return;
}
context.setNeedsNewLine(true);
if (lastWrap != 0) {//found a place to wrap
context.setEnd(context.getStart() + lastWrap);
context.setWidth(lastGraphicsLength);
} else {//unbreakable string
if (left == 0) {
left = currentString.length();
}
context.setEnd(context.getStart() + left);
context.setUnbreakable(true);
if (left == currentString.length()) {
context.setWidth(c.getTextRenderer().getWidth(
c.getFontContext(), font, context.getCalculatedSubstring()));
} else {
context.setWidth(graphicsLength);
}
}
return;
}
private static boolean isChinese(char c) {
Character.UnicodeBlock ub = Character.UnicodeBlock.of(c);
return (ub == Character.UnicodeBlock.CJK_UNIFIED_IDEOGRAPHS)
|| (ub == Character.UnicodeBlock.CJK_COMPATIBILITY_IDEOGRAPHS)
|| (ub == Character.UnicodeBlock.CJK_UNIFIED_IDEOGRAPHS_EXTENSION_A)
|| (ub == Character.UnicodeBlock.CJK_SYMBOLS_AND_PUNCTUATION)
|| (ub == Character.UnicodeBlock.GENERAL_PUNCTUATION)
|| (ub == Character.UnicodeBlock.HALFWIDTH_AND_FULLWIDTH_FORMS);
}
private static int getStrRight(String a, int left) {
if (left > a.length()) {
return -1;
}
char[] ch = a.toCharArray();
for (int i = left; i < ch.length; ++i) {
if ((isChinese(ch[i]))
|| (WhitespaceStripper.SPACE.toCharArray()[0] == ch[i])
|| (a.indexOf(WhitespaceStripper.SPACE) < 0)) {
return (i == 0) ? i + 1 : i;
}
}
return -1;
}
}