package net.sf.statsvn.input;
   
   import java.text.ParseException;
   import java.util.ArrayList;
   import java.util.Date;
   import java.util.HashMap;
   
   import net.sf.statsvn.output.SvnConfigurationOptions;
   import net.sf.statsvn.util.XMLUtil;
  
  import org.xml.sax.Attributes;
  import org.xml.sax.SAXException;
  import org.xml.sax.SAXParseException;
  import org.xml.sax.helpers.DefaultHandler;
  
  /**
   * This is the SAX parser for the svn log in xml format. It feeds information to
   * the (@link net.sf.statsvn.input.SvnLogBuilder).
   * 
   * @author Jason Kealey <jkealey@shade.ca>
   * @author Gunter Mussbacher <gunterm@site.uottawa.ca>
   * 
   * @version $Id: SvnXmlLogFileHandler.java 351 2008-03-28 18:46:26Z benoitx $
   */
  public class SvnXmlLogFileHandler extends DefaultHandler {
  
  	private static final String INVALID_SVN_LOG_FILE = "Invalid SVN log file.";
  
  	private static final String AUTHOR = "author";
  
  	private static final String DATE = "date";
  
  	private static final String FATAL_ERROR_MESSAGE = INVALID_SVN_LOG_FILE;
  
  	private static final String LOG = "log";
  
  	private static final String LOGENTRY = "logentry";
  
  	private static final String MSG = "msg";
  
  	private static final String PATH = "path";
  
  	private static final String PATHS = "paths";
  
  	private final SvnLogBuilder builder;
  
  	private ArrayList currentFilenames;
  
  	private RevisionData currentRevisionData;
  
  	private ArrayList currentRevisions;
  
  	private String lastElement = "";
  
  	private String pathAction = "";
  
  	private String stringData = "";
  
  	private String copyfromRev = "";
  
  	private String copyfromPath = "";
  
  	private final RepositoryFileManager repositoryFileManager;
  
  	private final HashMap tagsMap = new HashMap();
  
  	private final HashMap tagsDateMap = new HashMap();
  
  	/**
  	 * Default constructor.
  	 * 
  	 * @param builder
  	 *            where to send the information
  	 * @param repositoryFileManager
  	 *            the repository file manager needed to obtain some information.
  	 */
  	public SvnXmlLogFileHandler(final SvnLogBuilder builder, final RepositoryFileManager repositoryFileManager) {
  		this.builder = builder;
  		this.repositoryFileManager = repositoryFileManager;
  	}
  
  	/**
  	 * Builds the string that was read; default implementation can invoke this
  	 * function multiple times while reading the data.
  	 */
  	public void characters(final char[] ch, final int start, final int length) throws SAXException {
  		super.characters(ch, start, length);
  		stringData += new String(ch, start, length);
  	}
  
  	/**
  	 * Makes sure the last element received is appropriate.
  	 * 
  	 * @param last
  	 *            the expected last element.
  	 * @throws SAXException
  	 *             unexpected event.
  	 */
  	private void checkLastElement(final String last) throws SAXException {
 		if (!lastElement.equals(last)) {
 			fatalError(FATAL_ERROR_MESSAGE);
 		}
 	}
 
 	/**
 	 * End of author element. Saves author to the current revision.
 	 * 
 	 * @throws SAXException
 	 *             unexpected event.
 	 */
 	private void endAuthor() throws SAXException {
 		checkLastElement(LOGENTRY);
 		currentRevisionData.setLoginName(stringData);
 	}
 
 	/**
 	 * End of date element. See (@link XMLUtil#parseXsdDateTime(String)) for
 	 * parsing of the particular datetime format.
 	 * 
 	 * Saves date to the current revision.
 	 * 
 	 * @throws SAXException
 	 *             unexpected event.
 	 */
 	private void endDate() throws SAXException {
 		checkLastElement(LOGENTRY);
 		Date dt;
 		try {
 			dt = XMLUtil.parseXsdDateTime(stringData);
 			currentRevisionData.setDate(dt);
 		} catch (final ParseException e) {
 			warning("Invalid date specified.");
 		}
 	}
 
 	/**
 	 * Handles the end of an xml element and redirects to the appropriate end*
 	 * method.
 	 * 
 	 * @throws SAXException
 	 *             unexpected event.
 	 */
 	public void endElement(final String uri, final String localName, final String qName) throws SAXException {
 		super.endElement(uri, localName, qName);
 		String eName = localName; // element name
 		if ("".equals(eName)) {
 			eName = qName; // namespaceAware = false
 		}
 		if (eName.equals(LOG)) {
 			endLog();
 		} else if (eName.equals(LOGENTRY)) {
 			endLogEntry();
 		} else if (eName.equals(AUTHOR)) {
 			endAuthor();
 		} else if (eName.equals(DATE)) {
 			endDate();
 		} else if (eName.equals(MSG)) {
 			endMsg();
 		} else if (eName.equals(PATHS)) {
 			endPaths();
 		} else if (eName.equals(PATH)) {
 			endPath();
 		} else {
 			fatalError(INVALID_SVN_LOG_FILE);
 		}
 	}
 
 	/**
 	 * End of log element.
 	 * 
 	 * @throws SAXException
 	 *             unexpected event.
 	 */
 	private void endLog() throws SAXException {
 		checkLastElement(LOG);
 		lastElement = "";
 	}
 
 	/**
 	 * End of log entry element. For each file that was found, builds the file
 	 * and revision in (@link SvnLogBuilder).
 	 * 
 	 * @throws SAXException
 	 *             unexpected event.
 	 */
 	private void endLogEntry() throws SAXException {
 		checkLastElement(LOGENTRY);
 		lastElement = LOG;
 
 		for (int i = 0; i < currentFilenames.size(); i++) {
 			if (currentFilenames.get(i) == null) {
 				continue; // skip files that are not on this branch
 			}
 			final RevisionData revisionData = (RevisionData) currentRevisions.get(i);
 			revisionData.setComment(currentRevisionData.getComment());
 			revisionData.setDate(currentRevisionData.getDate());
 			revisionData.setLoginName(currentRevisionData.getLoginName());
 			final String currentFilename = currentFilenames.get(i).toString();
 
 			final boolean isBinary = repositoryFileManager.isBinary(currentFilename);
 			builder.buildFile(currentFilename, isBinary, revisionData.isDeletion(), tagsMap, tagsDateMap);
 			builder.buildRevision(revisionData);
 		}
 	}
 
 	/**
 	 * End of msg element. Saves comment to the current revision.
 	 * 
 	 * @throws SAXException
 	 *             unexpected event.
 	 */
 	private void endMsg() throws SAXException {
 		checkLastElement(LOGENTRY);
 		currentRevisionData.setComment(stringData);
 	}
 
 	/**
 	 * End of path element. Builds a revision data for this element using the
 	 * information that is known to date; rest is done in (@link #endLogEntry())
 	 * 
 	 * @throws SAXException
 	 *             unexpected event.
 	 */
 	private void endPath() throws SAXException {
 		checkLastElement(PATHS);
 
 		// relies on the fact that absoluteToRelativePath returns null for paths
 		// that are not on the branch.
 		final String filename = repositoryFileManager.absoluteToRelativePath(stringData);
 		final RevisionData data = currentRevisionData.createCopy();
 		if (!pathAction.equals("D")) {
 			data.setStateExp(true);
 			if (pathAction.equals("A") || pathAction.equals("R")) {
 				data.setStateAdded(true);
 			}
 		} else {
 			data.setStateDead(true);
 		}
 
 		final String tagsStr = SvnConfigurationOptions.getTagsDirectory();
 		if (copyfromRev != null && filename == null && stringData != null && stringData.indexOf(tagsStr) >= 0) {
 			String tag = stringData.substring(stringData.indexOf(tagsStr) + tagsStr.length());
 			if (tag.indexOf("/") >= 0) {
 				tag = tag.substring(0, tag.indexOf("/"));
 			}
 
 			if (!tagsMap.containsKey(tag) && builder.matchesTagPatterns(tag)) {
 				SvnConfigurationOptions.getTaskLogger().info("= TAG " + tag + " rev:" + copyfromRev + " stringData [" + stringData + "]");
 				tagsMap.put(tag, copyfromRev);
 				tagsDateMap.put(tag, currentRevisionData.getDate());
 			}
 		}
 
 		data.setCopyfromPath(copyfromPath);
 		data.setCopyfromRevision(copyfromRev);
 
 		currentRevisions.add(data);
 		currentFilenames.add(filename);
 	}
 
 	/**
 	 * End of paths element.
 	 * 
 	 * @throws SAXException
 	 *             unexpected event.
 	 */
 	private void endPaths() throws SAXException {
 		checkLastElement(PATHS);
 		lastElement = LOGENTRY;
 	}
 
 	/**
 	 * Throws a fatal error with the specified message.
 	 * 
 	 * @param message
 	 *            the reason for the error
 	 * @throws SAXException
 	 *             the error
 	 */
 	private void fatalError(final String message) throws SAXException {
 		fatalError(new SAXParseException(message, null));
 	}
 
 	/**
 	 * Start of author, date or message.
 	 * 
 	 * @throws SAXException
 	 *             unexpected event.
 	 */
 	private void startAuthorDateMsg() throws SAXException {
 		checkLastElement(LOGENTRY);
 	}
 
 	/**
 	 * Handles the start of an xml element and redirects to the appropriate
 	 * start* method.
 	 * 
 	 * @throws SAXException
 	 *             unexpected event.
 	 */
 	public void startElement(final String uri, final String localName, final String qName, final Attributes attributes) throws SAXException {
 		super.startElement(uri, localName, qName, attributes);
 		stringData = "";
 		String eName = localName; // element name
 		if ("".equals(eName)) {
 			eName = qName; // namespaceAware = false
 		}
 		if (eName.equals(LOG)) {
 			startLog();
 		} else if (eName.equals(LOGENTRY)) {
 			startLogEntry(attributes);
 		} else if (eName.equals(AUTHOR) || eName.equals(DATE) || eName.equals(MSG)) {
 			startAuthorDateMsg();
 		} else if (eName.equals(PATHS)) {
 			startPaths();
 		} else if (eName.equals(PATH)) {
 			startPath(attributes);
 		} else {
 			fatalError(INVALID_SVN_LOG_FILE);
 		}
 	}
 
 	/**
 	 * Start of the log element.
 	 * 
 	 * @throws SAXException
 	 *             unexpected event.
 	 */
 	private void startLog() throws SAXException {
 		checkLastElement("");
 		lastElement = LOG;
 
 		try {
 			repositoryFileManager.loadInfo();
 			builder.buildModule(repositoryFileManager.getModuleName());
 		} catch (final Exception e) {
 			throw new SAXException(e);
 		}
 
 	}
 
 	/**
 	 * Start of the log entry element. Initializes information, to be filled
 	 * during this log entry and used in (@link #endLogEntry())
 	 * 
 	 * @throws SAXException
 	 *             unexpected event.
 	 */
 	private void startLogEntry(final Attributes attributes) throws SAXException {
 		checkLastElement(LOG);
 		lastElement = LOGENTRY;
 		currentRevisionData = new RevisionData();
 		currentRevisions = new ArrayList();
 		currentFilenames = new ArrayList();
 		if (attributes != null && attributes.getValue("revision") != null) {
 			currentRevisionData.setRevisionNumber(attributes.getValue("revision"));
 		} else {
 			fatalError(INVALID_SVN_LOG_FILE);
 		}
 	}
 
 	/**
 	 * Start of the path element. Saves the path action.
 	 * 
 	 * @throws SAXException
 	 *             unexpected event.
 	 */
 	private void startPath(final Attributes attributes) throws SAXException {
 		checkLastElement(PATHS);
 		if (attributes != null && attributes.getValue("action") != null) {
 			pathAction = attributes.getValue("action");
 		} else {
 			fatalError(INVALID_SVN_LOG_FILE);
 		}
 
 		copyfromPath = attributes.getValue("copyfrom-path");
 		copyfromRev = attributes.getValue("copyfrom-rev");
 
 	}
 
 	/**
 	 * Start of the paths element.
 	 * 
 	 * @throws SAXException
 	 *             unexpected event.
 	 */
 	private void startPaths() throws SAXException {
 		checkLastElement(LOGENTRY);
 		lastElement = PATHS;
 	}
 
 	/**
 	 * Logs a warning.
 	 * 
 	 * @param message
 	 *            the reason for the error
 	 * @throws SAXException
 	 *             the error
 	 */
 	private void warning(final String message) throws SAXException {
 		SvnConfigurationOptions.getTaskLogger().info(message);
 	}
 }