BBCodeParser.java

/**
 * 
 * Copyright (c) 2000-2012 Liferay, Inc. All rights reserved.
 * This library 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 library 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.
 * 
 * Copyright (c) 2009-2014 Câmara dos Deputados. Todos os direitos reservados.
 *
 * e-Democracia é um software livre; você pode redistribuí-lo e/ou modificá-lo dentro
 * dos termos da Licença Pública Geral Menor GNU como publicada pela Fundação do 
 * Software Livre (FSF); na versão 2.1 da Licença, ou (na sua opinião) qualquer versão.
 *
 * Este programa é distribuído na esperança de que possa ser  útil, mas SEM NENHUMA GARANTIA;
 * sem uma garantia implícita de ADEQUAÇÃO a qualquer MERCADO ou APLICAÇÃO EM PARTICULAR.
 * Veja a Licença Pública Geral Menor GNU para maiores detalhes. 
 * 
 */

package com.liferay.portal.parsers.bbcode;

import com.liferay.portal.kernel.util.GetterUtil;
import com.liferay.portal.kernel.util.IntegerWrapper;
import com.liferay.portal.kernel.util.SetUtil;

import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import java.util.Stack;

/**
 * @author Iliyan Peychev
 */
public class BBCodeParser {

	public static final int TYPE_DATA = 0x04;

	public static final int TYPE_TAG_END = 0x02;

	public static final int TYPE_TAG_START = 0x01;

	public static final int TYPE_TAG_START_END = TYPE_TAG_START | TYPE_TAG_END;

	public BBCodeParser() {
		_blockElements = SetUtil.fromArray(
			new String[] {
				"*", "center", "code", "justify", "left", "li", "list", "q",
				"quote", "right", "table", "td", "th", "tr"
			});

		_inlineElements = SetUtil.fromArray(
			new String[] {
				"b", "color", "font", "i", "img", "s", "size", "u", "url", "youtube"
			});

		_selfCloseElements = SetUtil.fromArray(new String[] {"*"});
	}

	public List<BBCodeItem> parse(String text) {
		List<BBCodeItem> bbCodeItems = new ArrayList<BBCodeItem>();

		BBCodeLexer bbCodeLexer = new BBCodeLexer(text);
		Stack<String> tags = new Stack<String>();
		IntegerWrapper marker = new IntegerWrapper();

		BBCodeToken bbCodeToken = null;

		while ((bbCodeToken = bbCodeLexer.getNextBBCodeToken()) != null) {
			handleData(bbCodeItems, bbCodeLexer, marker, bbCodeToken, text);

			if (bbCodeToken.getStartTag() == null) {
				handleTagEnd(bbCodeItems, tags, bbCodeToken);

				continue;
			}

			handleTagStart(bbCodeItems, tags, bbCodeToken);

			String startTag = bbCodeToken.getStartTag();

			if (!startTag.equals("code")) {
				continue;
			}

			while (true) {
				bbCodeToken = bbCodeLexer.getNextBBCodeToken();

				if (bbCodeToken == null) {
					break;
				}

				String endTag = GetterUtil.getString(bbCodeToken.getEndTag());

				if (endTag.equals("code")) {
					break;
				}
			}

			handleData(bbCodeItems, bbCodeLexer, marker, bbCodeToken, text);

			if (bbCodeToken != null) {
				handleTagEnd(bbCodeItems, tags, bbCodeToken);
			}
			else {
				break;
			}
		}

		handleData(bbCodeItems, bbCodeLexer, marker, null, text);
		handleTagEnd(bbCodeItems, tags, null);

		return bbCodeItems;
	}

	protected void handleData(
		List<BBCodeItem> bbCodeItems, BBCodeLexer bbCodeLexer,
		IntegerWrapper marker, BBCodeToken bbCodeToken, String data) {

		int length = data.length();

		int lastIndex = length;

		if (bbCodeToken != null) {
			length = bbCodeToken.getStart();

			lastIndex = bbCodeLexer.getLastIndex();
		}

		if (length > marker.getValue()) {
			BBCodeItem bbCodeItem = new BBCodeItem(
				TYPE_DATA, null, data.substring(marker.getValue(), length));

			bbCodeItems.add(bbCodeItem);
		}

		marker.setValue(lastIndex);
	}

	protected void handleTagEnd(
		List<BBCodeItem> bbCodeItems, Stack<String> tags,
		BBCodeToken bbCodeToken) {

		int size = 0;

		if (bbCodeToken != null) {
			String endTag = bbCodeToken.getEndTag();

			for (size = tags.size() - 1; size >= 0; size--) {
				if (endTag.equals(tags.elementAt(size))) {
					break;
				}
			}
		}

		if (size >= 0) {
			for (int i = tags.size() - 1; i >= size; i--) {
				BBCodeItem bbCodeItem = new BBCodeItem(
					TYPE_TAG_END, null, tags.elementAt(i));

				bbCodeItems.add(bbCodeItem);
			}

			tags.setSize(size);
		}
	}

	protected void handleTagStart(
		List<BBCodeItem> bbCodeItems, Stack<String> tags,
		BBCodeToken bbCodeToken) {

		String startTag = bbCodeToken.getStartTag();

		if (_blockElements.contains(startTag)) {
			String currentTag = null;

			while (!tags.isEmpty() &&
				   ((currentTag = tags.lastElement()) != null) &&
				   _inlineElements.contains(currentTag)) {

				BBCodeToken currentTagBBCodeToken = new BBCodeToken(currentTag);

				handleTagEnd(bbCodeItems, tags, currentTagBBCodeToken);
			}
		}

		if (_selfCloseElements.contains(startTag) &&
			!tags.isEmpty() && startTag.equals(tags.lastElement())) {

			BBCodeToken tagBBCodeToken = new BBCodeToken(startTag);

			handleTagEnd(bbCodeItems, tags, tagBBCodeToken);
		}

		tags.push(startTag);

		BBCodeItem bbCodeItem = new BBCodeItem(
			TYPE_TAG_START, bbCodeToken.getAttribute(), startTag);

		bbCodeItems.add(bbCodeItem);
	}

	private Set<String> _blockElements;
	private Set<String> _inlineElements;
	private Set<String> _selfCloseElements;

}