/*
 * This library 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 library 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 library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package com.arsdigita.cms.contentassets;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import com.arsdigita.auditing.AuditingObserver;
import com.arsdigita.auditing.BasicAuditTrail;
import com.arsdigita.cms.ContentItem;
import com.arsdigita.cms.ImageAsset;
import com.arsdigita.domain.DomainCollection;
import com.arsdigita.domain.DomainObject;
import com.arsdigita.domain.DomainObjectFactory;
import com.arsdigita.domain.DomainObjectInstantiator;
import com.arsdigita.kernel.ACSObject;
import com.arsdigita.kernel.User;
import com.arsdigita.kernel.permissions.PermissionService;
import com.arsdigita.persistence.DataCollection;
import com.arsdigita.persistence.DataObject;
import com.arsdigita.persistence.Session;
import com.arsdigita.persistence.SessionManager;
import com.arsdigita.util.Assert;

import org.apache.log4j.Logger;

/**
 * 
 * 
 */
public class Note extends ACSObject {

    private static final Logger s_log = Logger.getLogger(Note.class);
    /**  PDL stuff                                                            */
    public static final String BASE_DATA_OBJECT_TYPE =
                               "com.arsdigita.cms.contentassets.Note";

    static {
        s_log.debug("Static initalizer is starting...");
        DomainObjectFactory.registerInstantiator(
                BASE_DATA_OBJECT_TYPE,
                new DomainObjectInstantiator() {
            @Override
            public DomainObjectInstantiator resolveInstantiator(DataObject dataObject) {
                return this;
            }

            protected DomainObject doNewInstance(DataObject dataObject) {
                return new Note(dataObject);
            }

        });

        s_log.debug("Static initalizer finished.");
    }

    public static final String CONTENT = "content";
    public static final String RANK = "rank";
    public static final String OWNER = "owner";
    public static final String NOTES = "ca_notes";
    public static final String AUDIT = "auditing";
    public static final String CREATION_DATE = AUDIT + "."
                                               + BasicAuditTrail.CREATION_DATE;
    private BasicAuditTrail auditTrail;
    private boolean m_isNew = false;

    private Note() {
        super(BASE_DATA_OBJECT_TYPE);
    }

    public Note(String type) {
        super(type);
    }

    public Note(DataObject obj) {
        super(obj);
    }

    public static Note create(ContentItem item) {
        DataCollection notes = getNotes(item);
        long nextRank = notes.size();

        Note note = new Note();
        note.set(OWNER, item);
        note.set(RANK, new Long((int) nextRank));

        return note;
    }

    /**
     * Register auditing observer 
     *  (non-Javadoc)
     * @see com.arsdigita.domain.DomainObject#initialize()
     */
    @Override
    protected void initialize() {
        super.initialize();

        DataObject dataObj = (DataObject) get(AUDIT);
        if (dataObj != null) {
            auditTrail = new BasicAuditTrail(dataObj);
        } else {
            // creates a new one when one doesn't already exist
            auditTrail = BasicAuditTrail.retrieveForACSObject(this);
        }

        addObserver(new AuditingObserver(auditTrail));
    }

    public String getContent() {
        return (String) get(CONTENT);
    }

    public void setContent(String content) {
        set(CONTENT, content);
    }

    public long getRank() {
        Long rank = (Long) get(RANK);
        Assert.exists(rank, Long.class);

        return rank.longValue();
    }

    public void setRank(long newRank) {
        DataCollection notes = getNotes(getOwner());

        if (newRank < 0) {
            newRank = 0;
        }

        Note last = null;
        long currentRank = 0;
        while (notes.next()) {
            if (newRank == currentRank) {
                currentRank++;
            }

            Note current = (Note) DomainObjectFactory.newInstance(notes.getDataObject());

            if (equals(current)) {
                continue;
            }

            if (current.getRank() != currentRank) {
                current.set(RANK, new Long(currentRank));
            }

            currentRank++;
        }
        notes.close();

        if (newRank > currentRank) {
            set(RANK, new Long(currentRank));
        } else {
            set(RANK, new Long(newRank));
        }
    }

    public ContentItem getOwner() {
        DataObject obj = (DataObject) get(OWNER);
        Assert.exists(obj, DataObject.class);

        return (ContentItem) DomainObjectFactory.newInstance(obj);
    }

    public User getNoteAuthor() {
        return auditTrail.getCreationUser();
    }

    public Date getCreationDate() {
        return auditTrail.getCreationDate();
    }

    public static DataCollection getNotes(ContentItem item) {
        Assert.exists(item, ContentItem.class);

        if (s_log.isDebugEnabled()) {
            s_log.debug("Retrieving notes for " + item.getOID());
        }

        DataCollection notes = SessionManager.getSession().retrieve(BASE_DATA_OBJECT_TYPE);

        notes.addEqualsFilter(OWNER, item.getID());
        notes.addOrder(RANK);

        return notes;
    }

    @Override
    protected void beforeDelete() {
        // Put this note at the end so other notes will be correctly reordered
        setRank(Long.MAX_VALUE);
    }

    @Override
    protected void beforeSave() {
        super.beforeSave();

        if (isNew()) {
            m_isNew = true;
        }
    }

    @Override
    protected void afterSave() {
        super.afterSave();

        if (m_isNew) {
            PermissionService.setContext(this, getOwner());
            m_isNew = false;
        }
    }

    /**
     * Retrieves all objects of this type stored in the database. Very
     * necessary for exporting all entities of the current work environment.
     *
     * @return List of all objects
     */
    public static List<Note> getAllObjects() {
        List<Note> objectList = new ArrayList<>();

        final Session session = SessionManager.getSession();
        DomainCollection collection = new DomainCollection(session.retrieve(
                Note.BASE_DATA_OBJECT_TYPE));

        while (collection.next()) {
            Note object = (Note) collection
                    .getDomainObject();
            if (object != null) {
                objectList.add(object);
            }
        }

        collection.close();
        return objectList;
    }

}