TOCBuilder.java

/**
 * Copyright 2011-2012 Alexandre Dutra
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */
/**
 * 
 */
package fr.dutra.confluence2wordpress.core.toc;

import static com.atlassian.confluence.content.render.xhtml.XhtmlConstants.*;

import java.io.UnsupportedEncodingException;
import java.net.MalformedURLException;
import java.net.URISyntaxException;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.xml.xpath.XPathExpressionException;

import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

import com.atlassian.confluence.content.render.xhtml.HtmlElementIdCreator;
import com.atlassian.confluence.renderer.PageContext;

import fr.dutra.confluence2wordpress.core.author.Author;
import fr.dutra.confluence2wordpress.util.StaxUtils;
import fr.dutra.confluence2wordpress.util.XPathUtils;


/**
 * @author Alexandre Dutra
 *
 */
public class TOCBuilder {

    private static final String AUTHOR = "author";

	private static final String H1 = "h1";
	private static final String H2 = "h2";
	private static final String H3 = "h3";
	private static final String H4 = "h4";
	private static final String H5 = "h5";
	private static final String H6 = "h6";

	private static final String NAME = "name";

	private static final String LOCAL_NAME_PARAMETER_XPATH = "*[local-name()='parameter']";

	private static final String MAIN_XPATH = "//*[name()='h1' or name()='h2' or name()='h3' or name()='h4' or name()='h5' or name()='h6' or name()='ac:macro']";

	private Heading current;
    
    private List<Heading> headings = new ArrayList<Heading>();

	private Heading root;

	private PageContext pageContext;

    public List<Heading> getHeadings() {
        return headings;
    }
    
	public Heading buildTOC(String storage, PageContext pageContext) throws TOCException {
		this.pageContext = pageContext;
		this.root = new Heading(0);
		this.root.setLabel(pageContext.getPageTitle());
		this.current = this.root;
		try {
			NodeList nodes = XPathUtils.evaluateXPathAsNodeList(StaxUtils.getReader(storage), MAIN_XPATH);
			for(int i = 0; i < nodes.getLength(); i++) {
				Node node = nodes.item(i);
				String name = node.getNodeName();
				if(name.equals(H1)){
					gotHeading(1, node);
				} else if(name.equals(H2)){
					gotHeading(2, node);
				} else if(name.equals(H3)){
					gotHeading(3, node);
				} else if(name.equals(H4)){
					gotHeading(4, node);
				} else if(name.equals(H5)){
					gotHeading(5, node);
				} else if(name.equals(H6)){
					gotHeading(6, node);
				} else {
					String macroName = node.getAttributes().getNamedItemNS(CONFLUENCE_XHTML_NAMESPACE_URI, NAME).getTextContent();
					if(AUTHOR.equals(macroName)){
						gotAuthorMacro(node);
					}
				}
			}
		} catch (Exception e) {
			String message = "Could not parse storage";
			if(e.getMessage() != null) {
				message += ": " + e.getMessage();
			}
			if(e.getCause() != null && e.getCause().getMessage() != null) {
				message += ": " + e.getCause().getMessage();
			}
			throw new TOCException(message, e);
		}
		return this.root;
	}

	private void gotHeading(int level, Node node) {
		Heading heading = new Heading(level);
		String body = node.getTextContent();
		heading.setLabel(body);
		try {
			//AbstractPageLink.generateAnchor generates the final anchor
			//but escaped for XML storage. We need URLencode instead,
			//so we are basically doing exactly what generateAnchor does
			//less the XML escaping.
			//AbstractPageLink.generateAnchor(pageContext, body);
			String anchor = URLEncoder.encode(HtmlElementIdCreator.convertToIdHtml5(pageContext.getPageTitle() + "-" + body), "UTF-8");
			heading.setAnchor(anchor);
		} catch (UnsupportedEncodingException e) {
		}
		Heading parent = findParentHeading(level);
		parent.addChild(heading);
		heading.setParent(parent);
		current = heading;
	}

	private Heading findParentHeading(int level) {
		Heading cur = current;
		while(cur != root && cur.getLevel() >= level) {
			cur = cur.getParent();
		}
		// this was abandoned since we mainly use H3 as uppermost level headings
//		while(level - cur.getLevel()  > 1) {
//			Heading h = new Heading(cur.getLevel() + 1);
//			h.setParent(cur);
//			cur.addChild(h);
//			cur = h;
//		}
		return cur;
	}

	private void gotAuthorMacro(Node authorNode) throws XPathExpressionException, MalformedURLException, URISyntaxException {
		Map<String, String> parameters = getAuthorMacroParameters(authorNode);
		Author author = Author.fromMacroParameters(parameters);
		current.setAuthor(author);
	}

	private Map<String, String> getAuthorMacroParameters(Node authorNode) throws XPathExpressionException {
		Map<String,String> parameters = new HashMap<String, String>();
		NodeList parameterNodes = XPathUtils.evaluateXPathAsNodeList(authorNode, LOCAL_NAME_PARAMETER_XPATH);
		for(int i = 0; i < parameterNodes.getLength(); i++) {
			Node parameterNode = parameterNodes.item(i);
			String key = parameterNode.getAttributes().getNamedItemNS(CONFLUENCE_XHTML_NAMESPACE_URI, NAME).getTextContent();
			String value = parameterNode.getTextContent();
			parameters.put(key, value);
		}
		return parameters;
	}
	
}