/src/main/java/org/andya/confluence/utils/page/LabelExpressionVisitor.java

/*

 * Copyright (c) 2006, 2007 Andy Armstrong, Kelsey Grant and other contributors.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are met:

 *

 *     * Redistributions of source code must retain the above copyright notice,

 *       this list of conditions and the following disclaimer.

 *     * Redistributions in binary form must reproduce the above copyright notice,

 *       this list of conditions and the following disclaimer in the documentation

 *       and/or other materials provided with the distribution.

 *     * The names of contributors may not

 *       be used to endorse or promote products derived from this software without

 *       specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR

 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON

 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */



package org.andya.confluence.utils.page;



import java.util.LinkedList;

import java.util.List;



import com.atlassian.confluence.core.ContentEntityObject;

import com.atlassian.confluence.labels.Label;

import com.atlassian.confluence.labels.LabelManager;

import com.atlassian.confluence.labels.LabelParser;

import com.atlassian.confluence.labels.ParsedLabelName;

import com.atlassian.confluence.pages.Page;

import com.opensymphony.util.TextUtils;

import org.andya.confluence.utils.parse.ExpressionVisitor;

import org.andya.confluence.utils.parse.OrExpression;

import org.andya.confluence.utils.parse.AndExpression;

import org.andya.confluence.utils.parse.LabelExpression;



/**

 * Walks a label expression tree collecting the appropriate pages

 * 

 * @author kelsey

 *

 */

class LabelExpressionVisitor implements ExpressionVisitor {



	/** The pages we have collected */

	private List<Page> pages;



	private final PageSearchContext context;



	public LabelExpressionVisitor(PageSearchContext context) {

		this.context = context;

	}



	/**

	 * Get the pages that have matched this expression. Returns null if this

	 * visitor has not visited an expression yet.

	 * 

	 * @return the pages that have matched this expression

	 */

	public List<Page> getPages() {

		return pages;

	}



	public void visit(OrExpression or) {

		or.getLeft().accept(this);

		List<Page> pagesLeft = this.pages;

		or.getRight().accept(this);

		List<Page> pagesRight = this.pages;



		// add them all!

		pagesLeft.addAll(pagesRight);

		this.pages = pagesLeft;

	}



	public void visit(AndExpression and) {

		and.getLeft().accept(this);

		List<Page> pagesLeft = this.pages;

		and.getRight().accept(this);

		List<Page> pagesRight = this.pages;



		// only keep if in both

		pagesLeft.retainAll(pagesRight);

		this.pages = pagesLeft;

	}



	@SuppressWarnings("unchecked")

	public void visit(LabelExpression labelExpression) {

		this.pages = new LinkedList<Page>();

		final LabelManager labelManager = context.getLabelManager();

		final String spaceKey = context.getSpaceKey();

		String labelName = labelExpression.getLabel();



		ParsedLabelName ref = LabelParser.parse(labelName);

		if (ref != null)

		{

			Label label = labelManager.getLabel(ref);

			if (label != null)

			{

				List<ContentEntityObject> entities;

				if (TextUtils.stringSet(spaceKey))

					entities = labelManager.getCurrentContentForLabelAndSpace(label, spaceKey);

				else

					entities = labelManager.getCurrentContentForLabel(label);

				for (ContentEntityObject entity : entities) {

					if(entity instanceof Page)

						pages.add((Page)entity);					

				}

			}

		}

	}





}