/* An actor to generate MoML strings from the input models.

@Copyright (c) 2008-2009 The Regents of the University of California.
All rights reserved.

Permission is hereby granted, without written agreement and without
license or royalty fees, to use, copy, modify, and distribute this
software and its documentation for any purpose, provided that the
above copyright notice and the following two paragraphs appear in all
copies of this software.

IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.

THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE
PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
ENHANCEMENTS, OR MODIFICATIONS.

                        PT_COPYRIGHT_VERSION_2
                        COPYRIGHTENDKEY



 */

package ptolemy.actor.gt;

import ptolemy.actor.lib.Transformer;
import ptolemy.data.ActorToken;
import ptolemy.data.StringToken;
import ptolemy.data.type.BaseType;
import ptolemy.kernel.CompositeEntity;
import ptolemy.kernel.util.IllegalActionException;
import ptolemy.kernel.util.NameDuplicationException;
import ptolemy.kernel.util.Workspace;

/**
 An actor to generate MoML strings from the input models.

 @author Thomas Huining Feng
 @version $Id$
 @since Ptolemy II 7.1
 @Pt.ProposedRating Yellow (tfeng)
 @Pt.AcceptedRating Red (tfeng)
 */
public class MoMLGenerator extends Transformer {

    /** Construct an actor with the given container and name.
     *  @param container The container.
     *  @param name The name of this actor.
     *  @exception IllegalActionException If the actor cannot be contained
     *   by the proposed container.
     *  @exception NameDuplicationException If the container already has an
     *   actor with this name.
     */
    public MoMLGenerator(CompositeEntity container, String name)
            throws NameDuplicationException, IllegalActionException {
        super(container, name);
        input.setTypeEquals(ActorToken.TYPE);
        output.setTypeEquals(BaseType.STRING);
    }

    /** Read the model presented at the input port, and output its moml to the
     *  output port.
     *
     *  @exception IllegalActionException If the model cannot be read or the
     *   moml cannot be produced.
     */
    public void fire() throws IllegalActionException {
        ActorToken token = (ActorToken) input.get(0);
        output.send(0, new StringToken(token.getEntity(new Workspace())
                .exportMoML()));
    }

    /** Return true if there is a model at the input port, or false otherwise.
     *
     *  @return true if there is a model at the input port, or false otherwise.
     *  @exception IllegalActionException If availability of input tokens cannot
     *   be tested.
     */
    public boolean prefire() throws IllegalActionException {
        return super.prefire() && input.hasToken(0);
    }
}