/**
 * Copyright (C) 2009 eXo Platform SAS.
 *
 * This 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 software 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.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.exoplatform.commons.chromattic;

import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;

import javax.jcr.RepositoryException;
import javax.jcr.Session;

import org.chromattic.api.ChromatticSession;
import org.exoplatform.services.jcr.core.ManageableRepository;

/**
 * An abstract implementation of the {@link org.exoplatform.commons.chromattic.SessionContext} interface. The context owns the
 * chromattic session.
 *
 * @author <a href="mailto:julien.viet@exoplatform.com">Julien Viet</a>
 * @version $Revision$
 */
abstract class AbstractContext implements SessionContext {

    /** . */
    ChromatticSession session;

    /** . */
    private Map<String, Object> attributes;

    /** The related life cycle. */
    final ChromatticLifeCycle lifeCycle;

    /** . */
    private HashSet<SynchronizationListener> listeners;

    AbstractContext(ChromatticLifeCycle lifeCycle) {
        this.lifeCycle = lifeCycle;
        this.session = null;
        this.listeners = null;
    }

    public final ChromatticSession getSession() {
        if (session == null) {
            session = lifeCycle.realChromattic.openSession();
        }
        return session;
    }

    public final Object getAttachment(String name) {
        if (attributes != null) {
            return attributes.get(name);
        }
        return null;
    }

    public final void setAttachment(String name, Object attribute) {
        if (attribute != null) {
            if (attributes == null) {
                attributes = new HashMap<String, Object>();
            }
            attributes.put(name, attribute);
        } else if (attributes != null) {
            attributes.remove(name);
        }
    }

    public abstract Session doLogin() throws RepositoryException;

    /**
     * Open and returns a session. Should be used by subclasses.
     *
     * @return a session
     * @throws RepositoryException any repository exception
     */
    protected final Session openSession() throws RepositoryException {
        ManageableRepository repo = lifeCycle.manager.repositoryService.getCurrentRepository();
        return repo.getSystemSession(lifeCycle.getWorkspaceName());
    }

    public void close(boolean save) {
        if (listeners != null) {
            for (SynchronizationListener listener : listeners) {
                try {
                    listener.beforeSynchronization();
                } catch (Exception e) {
                    // to log
                }
            }
        }

        //
        if (session != null) {
            if (save) {
                session.save();
            }

            //
            session.close();
        }

        //
        if (listeners != null) {
            SynchronizationStatus status = save ? SynchronizationStatus.SAVED : SynchronizationStatus.DISCARDED;
            for (SynchronizationListener listener : listeners) {
                try {
                    listener.afterSynchronization(status);
                } catch (Exception e) {
                    // to log
                }
            }
        }
    }

    public final void addSynchronizationListener(SynchronizationListener listener) {
        if (listener == null) {
            throw new NullPointerException();
        }
        if (listeners == null) {
            listeners = new HashSet<SynchronizationListener>();
        }
        listeners.add(listener);
    }
}
