/*
 Wotonomy: OpenStep design patterns for pure Java applications.
 Copyright (C) 2001 Michael Powers

 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, see http://www.gnu.org
 */
package net.wotonomy.access;

import net.wotonomy.control.EOClassDescription;
import net.wotonomy.control.EOEditingContext;
import net.wotonomy.control.EOFetchSpecification;
import net.wotonomy.control.EOGlobalID;
import net.wotonomy.control.EOKeyValueCodingAdditions;
import net.wotonomy.foundation.NSArray;
import net.wotonomy.foundation.NSDictionary;
import net.wotonomy.foundation.NSMutableArray;

/**
*
* @author ezamudio@nasoft.com
* @author $Author: cgruber $
* @version $Revision: 894 $
*/
public class EODatabaseChannel {

	protected EODatabaseContext _context;
	protected EOAdaptorChannel _channel;
	protected EOEntity _currEntity;
	protected EOEditingContext _currEC;
	protected NSArray _attributes;
	protected boolean _locking;
	protected boolean _refreshing;

	public EODatabaseChannel(EODatabaseContext context) {
		super();
		_context = context;
		_channel = _context.adaptorContext().createAdaptorChannel();
	}

	public EOAdaptorChannel adaptorChannel() {
		return _channel;
	}

	public EODatabaseContext databaseContext() {
		return _context;
	}

	public void cancelFetch() {
		_channel.cancelFetch();
	}

	public Object fetchObject() {
		NSDictionary r = _channel.fetchRow();
		EOGlobalID gid = _currEntity.globalIDForRow(r);
		Object eo = _currEC.objectForGlobalID(gid);
		if (eo == null) {
			eo = EOClassDescription.classDescriptionForEntityName(_currEntity.name()).createInstanceWithEditingContext(_currEC, gid);
			if (eo instanceof EOKeyValueCodingAdditions)
				((EOKeyValueCodingAdditions)eo).takeValuesFromDictionary(r);
			else
				EOKeyValueCodingAdditions.DefaultImplementation.takeValuesFromDictionary(eo, r);
		} else {
			if (isRefreshingObjects()) {
				//TODO: refresh object (how?)
			}
		}
		return eo;
	}

	public boolean isFetchInProgress() {
		return _channel.isFetchInProgress();
	}

	public void setIsLocking(boolean flag) {
		_locking = flag;
	}

	public boolean isLocking() {
		return _locking;
	}

	public void setIsRefreshingObjects(boolean flag) {
		_refreshing = flag;
	}

	public boolean isRefreshingObjects() {
		return _refreshing;
	}

	public void selectObjectsWithFetchSpecification(EOFetchSpecification fspec, EOEditingContext ec) {
		setIsLocking(fspec.locksObjects());
		setIsRefreshingObjects(fspec.refreshesRefetchedObjects());
		setCurrentEditingContext(ec);
		setCurrentEntity(databaseContext().database().entityNamed(fspec.entityName()));
		NSMutableArray atts = new NSMutableArray();
		atts.addObjectsFromArray(_currEntity.attributes());
		adaptorChannel().selectAttributes(atts, fspec, isLocking(), _currEntity);
		adaptorChannel().setAttributesToFetch(atts);
		_attributes = atts;
	}

	public void setCurrentEditingContext(EOEditingContext ec) {
		_currEC = ec;
	}

	public void setCurrentEntity(EOEntity entity) {
		_currEntity = entity;
	}

}
/*
 * $Log$
 * Revision 1.2  2006/02/16 16:47:14  cgruber
 * Move some classes in to "internal" packages and re-work imports, etc.
 *
 * Also use UnsupportedOperationExceptions where appropriate, instead of WotonomyExceptions.
 *
 * Revision 1.1  2006/02/16 13:19:57  cgruber
 * Check in all sources in eclipse-friendly maven-enabled packages.
 *
 * Revision 1.2  2003/08/29 21:15:46  chochos
 * use EOEntity's globalIDForRow method.
 *
 * Revision 1.1  2003/08/19 01:54:43  chochos
 * The EODatabase layer still needs a lot of work, but it's on its way...
 *
 */