XPathSourceDoubleClickStrategy.java

/*******************************************************************************
 * Copyright (c) 2006 Oracle Corporation 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:
 *     Oracle Corporation - initial API and implementation
 *******************************************************************************/

package com.ebmwebsourcing.petals.common.xpath.internal.configuration;

import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.ITextDoubleClickStrategy;
import org.eclipse.jface.text.ITextViewer;

/**
 * @author Michal Chmielewski (michal.chmielewski@oracle.com)
 * @date Oct 25, 2006
 */
public class XPathSourceDoubleClickStrategy implements ITextDoubleClickStrategy {

	protected XPathWordDetector fWordDetector = new XPathWordDetector();
	protected ITextViewer fText;


	/**
	 * Do something on double-click. For us, this means selecting the right amount of
	 * characters to form word or string.
	 * 
	 * @see org.eclipse.jface.text.ITextDoubleClickStrategy#doubleClicked(org.eclipse.jface.text.ITextViewer)
	 */
	public void doubleClicked (ITextViewer part) {

		int pos = part.getSelectedRange().x;
		if (pos < 0)
			return;

		this.fText = part;
		if (!selectComment(pos))
			selectWord(pos);
	}


	/**
	 * @param caretPos
	 * @return
	 */
	protected boolean selectComment(int caretPos) {

		IDocument doc = this.fText.getDocument();
		int startPos, endPos;
		try {
			int pos = caretPos;
			char c = ' ';

			while (pos >= 0) {
				c = doc.getChar(pos);
				if (c == '\\') {
					pos -= 2;
					continue;
				}
				if (c == Character.LINE_SEPARATOR || c == '\"')
					break;
				--pos;
			}

			if (c != '\"')
				return false;

			startPos = pos;

			pos = caretPos;
			int length = doc.getLength();
			c = ' ';

			while (pos < length) {
				c = doc.getChar(pos);
				if (c == Character.LINE_SEPARATOR || c == '\"')
					break;
				++pos;
			}
			if (c != '\"')
				return false;

			endPos = pos;

			int offset = startPos + 1;
			int len = endPos - offset;
			this.fText.setSelectedRange(offset, len);
			return true;
		} catch (BadLocationException x) {
		}

		return false;
	}


	/**
	 * @param caretPos
	 * @return
	 */
	protected boolean selectWord(int caretPos) {

		IDocument doc = this.fText.getDocument();
		int startPos, endPos;
		try {
			int pos = caretPos;
			char c;

			while (pos >= 0) {
				c = doc.getChar(pos);
				if (! this.fWordDetector.isWordPart(c))
					break;
				--pos;
			}

			startPos = pos;

			pos = caretPos;
			int length = doc.getLength();

			while (pos < length) {
				c = doc.getChar(pos);
				if (!this.fWordDetector.isWordPart(c))
					break;
				++pos;
			}

			endPos = pos;
			selectRange(startPos, endPos);
			return true;

		} catch (BadLocationException x) {
			// nothing
		}

		return false;
	}


	/**
	 * @param startPos
	 * @param stopPos
	 */
	private void selectRange(int startPos, int stopPos) {
		int offset = startPos + 1;
		int length = stopPos - offset;
		this.fText.setSelectedRange(offset, length);
	}
}