/genesis/org.dftproject.pgv.core/src/org/dftproject/pgv/core/racp/PGVGedcom.java

package org.dftproject.pgv.core.racp;



import java.io.StringReader;

import java.io.UnsupportedEncodingException;

import java.net.URLEncoder;

import java.text.SimpleDateFormat;

import java.util.Arrays;

import java.util.Calendar;

import java.util.Collections;

import java.util.Date;

import java.util.HashSet;

import java.util.LinkedList;

import java.util.List;

import java.util.Set;

import java.util.regex.Matcher;

import java.util.regex.Pattern;



import org.apache.commons.logging.Log;

import org.apache.commons.logging.LogFactory;

import org.dftproject.gedcom.core.AbstractGedcom;

import org.dftproject.gedcom.core.GedcomPerson;

import org.dftproject.gedcom.core.GedcomReader;

import org.dftproject.gedcom.core.IGedcom;

import org.dftproject.gedcom.core.Line;

import org.dftproject.genesis.core.http.HttpManager;

import org.dftproject.genesis.core.persistence.IMemento;

import org.dftproject.genesis.data.genealogy.GenealogyConstants;

import org.dftproject.genesis.data.genealogy.ISource;

import org.dftproject.genesis.data.genealogy.impl.SourceImpl;

import org.dftproject.genesis.data.impl.AttributeImpl;

import org.dftproject.pgv.core.cache.CacheManager;

import org.dftproject.pgv.core.racp.factories.PGVGedcomFactory;



public class PGVGedcom extends AbstractGedcom implements IGedcom {



	private static final Log log = LogFactory.getLog(PGVGedcom.class);

	

	private final static Pattern tabbedLinePattern = Pattern.compile("^([^\\t]*)\\t([^\\t]*)$");



	private final Session session;

	private final String gedcomId;

	private String title;



	public PGVGedcom(Session session, String gedcomId) {

		this(session, gedcomId, null);

	}



	public PGVGedcom(Session session, String gedcomId, String title) {

		this.session = session;

		this.gedcomId = gedcomId;

		this.title = title;

	}



	public String getUrl() {

		return session.getUrl();

	}



	public Session getSession() {

		return session;

	}



	public String getGedcomId() {

		return gedcomId;

	}



	public String getTitle() {

		return title;

	}

	

	protected void initTitle() {

		String response = HttpManager.getDefault().getWebPage(session.getUrl() + "client.php?action=listgedcoms&" + session.getSessionComponent());

		if (response != null) {

			String[] lines = response.split("\n");

			if (lines.length > 1 && "SUCCESS".equals(lines[0]) && !lines[1].startsWith("<"))	{

				for (String line : lines) {

					Matcher matcher = tabbedLinePattern.matcher(line);

					if (matcher.matches() && gedcomId.equals(matcher.group(1))) {

						title = matcher.group(2);

					}

				}

			}

		}

	}



	public String getGedcomUrl() {

		try {

			return getUrl() + "index.php?ged=" + URLEncoder.encode(getGedcomId(), "UTF-8");

		} catch (UnsupportedEncodingException e) {

			return null;

		}

	}



	@Override

	public GedcomPerson getPerson(String id) {

		Line record = getRecord(id);

		if (record != null && "INDI".equals(record.getTag()))

			return new PGVPerson(this, id, record);

		return null;

	}



	public String getPersonUrl(String id) {

		try {

			return getUrl() + "individual.php?pid=" + id + "&ged=" + URLEncoder.encode(getGedcomId(), "UTF-8");

		} catch (UnsupportedEncodingException e) {

			return null;

		}

	}



	/**

	 * Returns the record associated with <code>id</code>.

	 * @return the record

	 */

	public Line getRecord(String id) {

		Line[] lines = getRecords(new String[] { id });

		if (lines.length > 0) {

			if (log.isDebugEnabled())

				log.debug(lines[0].toString(true));

			return lines[0];

		}

		log.error("Failed to get record for " + id);

		return null;

	}



	/**

	 * Returns the records associated with the <code>ids</code>.

	 * @param ids an array of record ids

	 * @return an array of records

	 */

	public Line[] getRecords(String[] ids) {

		if (!session.isValid() && !session.connect())

			return new Line[0];



		List<Line> lines = new LinkedList<Line>();



		// First try to get the record from the cache



		CacheManager cacheManager = CacheManager.getDefault();

		Date today = getToday();



		Set<String> xrefs = new HashSet<String>(Arrays.asList(ids));

		for (String xref : ids) {

			// The cache must have a retrieval date for a record



			Date retrievalDate = cacheManager.getRetrievalDate(getUrl(), gedcomId, xref);

			if (retrievalDate == null)

				continue;



			// The retrieval date must be on or after today



			if (!retrievalDate.after(today) && !retrievalDate.equals(today)) {

				// If not, we must have request a list of changes today



				Date lastGetChanges = cacheManager.getLastGetChanges(getUrl(), gedcomId);

				if (lastGetChanges != null && !lastGetChanges.after(today) && !lastGetChanges.equals(today)) {

					// If not, request the list of changes and invalidate old

					// records



					Set<String> changedXrefs = getChanges(lastGetChanges, session.getSessionComponent());

					cacheManager.invalidateRecords(getUrl(), gedcomId, today, changedXrefs);



					// This record must not have changed since the retrieval

					// date



					if (changedXrefs.contains(xref)) {

						log.info(xref + " has changed since " + new SimpleDateFormat("d MMM yyyy").format(retrievalDate));

						continue;

					}

				}

			}



			// Get the record from the cache



			String record = cacheManager.getRecord(getUrl(), gedcomId, xref);

			if (record != null) {

				xrefs.remove(xref);



				try {

					GedcomReader reader = new GedcomReader();

					lines.addAll(reader.read(new StringReader(record)));

				} catch (Exception e) {

					e.printStackTrace();

				}

			}

		}



		// Request all cache misses

		// TODO Batch record requests with one RACP call and split the results



		for (String xref : xrefs) {

			Date retrieved = new Date();

			String data = getRecords(new String[] { xref }, session.getSessionComponent());

			if (data != null) {

				cacheManager.putRecord(getUrl(), gedcomId, xref, data, retrieved);



				try {

					GedcomReader reader = new GedcomReader();

					lines.addAll(reader.read(new StringReader(data)));

				} catch (Exception e) {

					e.printStackTrace();

				}

			}

		}



		return lines.toArray(new Line[0]);

	}



	/**

	 * Returns a {@link Date} representing the beginning of today.

	 * @return a date

	 */

	protected Date getToday() {

		Calendar today = Calendar.getInstance();

		today.set(Calendar.HOUR_OF_DAY, 0);

		today.set(Calendar.MINUTE, 0);

		today.set(Calendar.SECOND, 0);

		today.set(Calendar.MILLISECOND, 0);

		return today.getTime();

	}



	/**

	 * Returns the data for the requested records.

	 * @param xrefs an array of xrefs

	 * @param sessionComponent the session component

	 * @return the data for the requested records, or null on failure

	 */

	protected String getRecords(String[] xrefs, String sessionComponent) {

		if (xrefs == null || xrefs.length == 0 || sessionComponent == null)

			return null;



		StringBuilder xrefParameter = new StringBuilder();

		for (String xref : xrefs)

			xrefParameter.append(xref);



		String contents= null;

		try {

			contents = HttpManager.getDefault().getWebPage(getUrl() + "client.php?action=get&GEDCOM=" + URLEncoder.encode(gedcomId, "UTF-8") + "&xref=" + xrefParameter + "&" + sessionComponent);

		} catch (UnsupportedEncodingException e) {

			log.error("Failed to encode HTTP query parameter as UTF-8", e);

		}

		if (contents == null)

			return null;



		String[] lines = contents.split("\n");

		if (lines.length < 2)

			return null;



		if ("SUCCESS".equals(lines[0]) && !lines[1].startsWith("<")) {

			StringBuilder data = new StringBuilder();

			for (int i = 1; i < lines.length; i++) {

				data.append(lines[i]);

				if (i < lines.length - 1)

					data.append("\n");

			}



			return data.toString();

		}



		return null;

	}



	/**

	 * Returns a set of xrefs for records that have changed since

	 * <code>date</code>.

	 * @param date a date

	 * @param sessionComponent the session component

	 * @return a set of xrefs for records that have changed

	 */

	protected Set<String> getChanges(Date date, String sessionComponent) {

		if (date == null || sessionComponent == null)

			return Collections.emptySet();



		String contents = HttpManager.getDefault().getWebPage(getUrl() + "client.php?action=getchanges&GEDCOM=" + gedcomId + "&date=" + date + "&" + sessionComponent);

		if (contents == null)

			return Collections.emptySet();



		String[] lines = contents.split("\n");

		if (lines.length < 2)

			return Collections.emptySet();



		if ("SUCCESS".equals(lines[0]) && !lines[1].startsWith("<")) {

			Set<String> xrefs = new HashSet<String>();

			for (String line : lines) {

				if (!"".equals(line.trim()))

					xrefs.add(line);

			}



			return xrefs;

		}



		return Collections.emptySet();

	}



	@Override

	public int hashCode() {

		final int prime = 31;

		int result = 1;

		result = prime * result + ((gedcomId == null) ? 0 : gedcomId.hashCode());

		result = prime * result + ((session == null) ? 0 : session.hashCode());

		return result;

	}



	@Override

	public boolean equals(Object obj) {

		if (this == obj)

			return true;

		if (obj == null)

			return false;

		if (getClass() != obj.getClass())

			return false;

		final PGVGedcom other = (PGVGedcom) obj;

		if (gedcomId == null) {

			if (other.gedcomId != null)

				return false;

		} else if (!gedcomId.equals(other.gedcomId))

			return false;

		if (session == null) {

			if (other.session != null)

				return false;

		} else if (!session.equals(other.session))

			return false;

		return true;

	}

	

	public ISource asSource(String id) {

		SourceImpl source = new SourceImpl();

		source.addAttribute(new AttributeImpl(GenealogyConstants.type, "org.dftproject.pgv.source"));

		if (title == null)

			initTitle();

		if (title != null)

			source.addAttribute(new AttributeImpl(GenealogyConstants.title, title));

		source.addAttribute(new AttributeImpl(GenealogyConstants.collection, this));

		source.addAttribute(new AttributeImpl("id", id));

		return source;

	}



	public String getFactoryId() {

		return PGVGedcomFactory.ID;

	}



	public void saveState(IMemento memento) {

		memento.putString("url", session.getUrl());

		memento.putString("gedcomId", gedcomId);

	}



}