/*
* Copyright (c) 2004-2011 Marco Maccaferri and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Marco Maccaferri - initial API and implementation
*/
package org.eclipsetrader.ui.internal.editors;
import java.io.IOException;
import java.io.StringReader;
import java.util.Hashtable;
import java.util.Vector;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.LineStyleEvent;
import org.eclipse.swt.custom.LineStyleListener;
import org.eclipse.swt.custom.StyleRange;
import org.eclipse.swt.custom.StyledText;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
public class JavaScriptLineStyler implements LineStyleListener {
public static final int EOF = -1;
public static final int EOL = 10;
public static final int WORD = 0;
public static final int WHITE = 1;
public static final int KEY = 2;
public static final int COMMENT = 3;
public static final int STRING = 5;
public static final int OTHER = 6;
public static final int NUMBER = 7;
public static final int MAXIMUM_TOKEN = 8;
private KeywordScanner scanner = new KeywordScanner();
private int[] tokenColors;
private Color[] colors;
private Vector<int[]> blockComments = new Vector<int[]>();
/**
* A simple fuzzy scanner
*/
public class KeywordScanner {
protected Hashtable<String, Integer> fgKeys = null;
protected StringBuffer fBuffer = new StringBuffer();
protected String fDoc;
protected int fPos;
protected int fEnd;
protected int fStartToken;
protected boolean fEofSeen = false;
private String[] fgKeywords = {
"function", "new", "return", "var",
"true", "false",
"if", "else", "do", "while",
};
public KeywordScanner() {
initialize();
}
/**
* Returns the ending location of the current token in the document.
*/
public final int getLength() {
return fPos - fStartToken;
}
/**
* Initialize the lookup table.
*/
void initialize() {
fgKeys = new Hashtable<String, Integer>();
Integer k = new Integer(KEY);
for (int i = 0; i < fgKeywords.length; i++) {
fgKeys.put(fgKeywords[i], k);
}
}
/**
* Returns the starting location of the current token in the document.
*/
public final int getStartOffset() {
return fStartToken;
}
/**
* Returns the next lexical token in the document.
*/
public int nextToken() {
int c;
fStartToken = fPos;
while (true) {
switch (c = read()) {
case EOF:
return EOF;
case '/': // comment
c = read();
if (c == '/') {
while (true) {
c = read();
if ((c == EOF) || (c == EOL)) {
unread(c);
return COMMENT;
}
}
}
unread(c);
return OTHER;
case '\'': // char const
while (true) {
c = read();
switch (c) {
case '\'':
return STRING;
case EOF:
unread(c);
return STRING;
case '\\':
c = read();
break;
}
}
case '"': // string
while (true) {
c = read();
switch (c) {
case '"':
return STRING;
case EOF:
unread(c);
return STRING;
case '\\':
c = read();
break;
}
}
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
do {
c = read();
} while (Character.isDigit((char) c));
unread(c);
return NUMBER;
default:
if (Character.isWhitespace((char) c)) {
do {
c = read();
} while (Character.isWhitespace((char) c));
unread(c);
return WHITE;
}
if (Character.isJavaIdentifierStart((char) c)) {
fBuffer.setLength(0);
do {
fBuffer.append((char) c);
c = read();
} while (Character.isJavaIdentifierPart((char) c));
unread(c);
Integer i = fgKeys.get(fBuffer.toString());
if (i != null) {
return i.intValue();
}
return WORD;
}
return OTHER;
}
}
}
/**
* Returns next character.
*/
protected int read() {
if (fPos <= fEnd) {
return fDoc.charAt(fPos++);
}
return EOF;
}
public void setRange(String text) {
fDoc = text;
fPos = 0;
fEnd = fDoc.length() - 1;
}
protected void unread(int c) {
if (c != EOF) {
fPos--;
}
}
}
public JavaScriptLineStyler() {
initializeColors();
scanner = new KeywordScanner();
}
Color getColor(int type) {
if (type < 0 || type >= tokenColors.length) {
return null;
}
return colors[tokenColors[type]];
}
boolean inBlockComment(int start, int end) {
for (int i = 0; i < blockComments.size(); i++) {
int[] offsets = blockComments.elementAt(i);
// start of comment in the line
if ((offsets[0] >= start) && (offsets[0] <= end)) {
return true;
}
// end of comment in the line
if ((offsets[1] >= start) && (offsets[1] <= end)) {
return true;
}
if ((offsets[0] <= start) && (offsets[1] >= end)) {
return true;
}
}
return false;
}
void initializeColors() {
Display display = Display.getDefault();
colors = new Color[] {
new Color(display, new RGB(0, 0, 0)), // black
new Color(display, new RGB(63, 127, 95)), // green
new Color(display, new RGB(42, 0, 255)), // blue
new Color(display, new RGB(127, 0, 85))
};
tokenColors = new int[MAXIMUM_TOKEN];
tokenColors[WORD] = 0;
tokenColors[WHITE] = 0;
tokenColors[KEY] = 3;
tokenColors[COMMENT] = 1;
tokenColors[STRING] = 2;
tokenColors[OTHER] = 0;
tokenColors[NUMBER] = 0;
}
void disposeColors() {
for (int i = 0; i < colors.length; i++) {
colors[i].dispose();
}
}
/**
* Event.detail line start offset (input)
* Event.text line text (input)
* LineStyleEvent.styles Enumeration of StyleRanges, need to be in order. (output)
* LineStyleEvent.background line background color (output)
*/
@Override
public void lineGetStyle(LineStyleEvent event) {
Vector<StyleRange> styles = new Vector<StyleRange>();
int token;
StyleRange lastStyle;
parseBlockComments(((StyledText) event.widget).getText());
// If the line is part of a block comment, create one style for the entire line.
if (inBlockComment(event.lineOffset, event.lineOffset + event.lineText.length())) {
styles.addElement(new StyleRange(event.lineOffset, event.lineText.length(), getColor(COMMENT), null));
event.styles = new StyleRange[styles.size()];
styles.copyInto(event.styles);
return;
}
Color defaultFgColor = ((Control) event.widget).getForeground();
scanner.setRange(event.lineText);
token = scanner.nextToken();
while (token != EOF) {
if (token == OTHER) {
// do nothing for non-colored tokens
}
else if (token != WHITE) {
Color color = getColor(token);
// Only create a style if the token color is different than the
// widget's default foreground color and the token's style is not
// bold. Keywords are bolded.
if ((!color.equals(defaultFgColor)) || (token == KEY)) {
StyleRange style = new StyleRange(scanner.getStartOffset() + event.lineOffset, scanner.getLength(), color, null);
if (token == KEY) {
style.fontStyle = SWT.BOLD;
}
if (styles.isEmpty()) {
styles.addElement(style);
}
else {
// Merge similar styles. Doing so will improve performance.
lastStyle = styles.lastElement();
if (lastStyle.similarTo(style) && (lastStyle.start + lastStyle.length == style.start)) {
lastStyle.length += style.length;
}
else {
styles.addElement(style);
}
}
}
}
else if ((!styles.isEmpty()) && ((lastStyle = styles.lastElement()).fontStyle == SWT.BOLD)) {
int start = scanner.getStartOffset() + event.lineOffset;
lastStyle = styles.lastElement();
// A font style of SWT.BOLD implies that the last style
// represents a java keyword.
if (lastStyle.start + lastStyle.length == start) {
// Have the white space take on the style before it to
// minimize the number of style ranges created and the
// number of font style changes during rendering.
lastStyle.length += scanner.getLength();
}
}
token = scanner.nextToken();
}
event.styles = new StyleRange[styles.size()];
styles.copyInto(event.styles);
}
public void parseBlockComments(String text) {
blockComments = new Vector<int[]>();
StringReader buffer = new StringReader(text);
int ch;
boolean blkComment = false;
int cnt = 0;
int[] offsets = new int[2];
boolean done = false;
try {
while (!done) {
switch (ch = buffer.read()) {
case -1: {
if (blkComment) {
offsets[1] = cnt;
blockComments.addElement(offsets);
}
done = true;
break;
}
case '/': {
ch = buffer.read();
if ((ch == '*') && (!blkComment)) {
offsets = new int[2];
offsets[0] = cnt;
blkComment = true;
cnt++;
}
else {
cnt++;
}
cnt++;
break;
}
case '*': {
if (blkComment) {
ch = buffer.read();
cnt++;
if (ch == '/') {
blkComment = false;
offsets[1] = cnt;
blockComments.addElement(offsets);
}
}
cnt++;
break;
}
default: {
cnt++;
break;
}
}
}
} catch (IOException e) {
// ignore errors
}
}
}