/* A criterion to constrain the name of an object in the host model.

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package ptolemy.actor.gt.ingredients.criteria;

import ptolemy.actor.gt.GTIngredientElement;
import ptolemy.actor.gt.GTIngredientList;
import ptolemy.actor.gt.ValidationException;
import ptolemy.actor.gt.util.PtolemyExpressionString;
import ptolemy.data.StringToken;
import ptolemy.kernel.util.IllegalActionException;
import ptolemy.kernel.util.NamedObj;

//////////////////////////////////////////////////////////////////////////
//// NameCriterion

/**
 A criterion to constrain the name of an object in the host model.

 @author Thomas Huining Feng
 @version $Id$
 @since Ptolemy II 8.0
 @Pt.ProposedRating Yellow (tfeng)
 @Pt.AcceptedRating Red (tfeng)
 */
public class DynamicNameCriterion extends Criterion {

    /** Construct a criterion within the given list as its owner. All elements
     *  are enabled and are initialized to empty at the beginning.
     *
     *  @param owner The list as the owner of the constructed GTIngredientList.
     */
    public DynamicNameCriterion(GTIngredientList owner) {
        this(owner, "");
    }

    /** Construct a criterion within the given list as its owner and initialize
     *  all the elements with the given values, which are a string encoding of
     *  those elements. All elements are enabled at the beginning.
     *
     *  @param owner The list as the owner of the constructed GTIngredientList.
     *  @param values The string encoding of the values of the elements.
     */
    public DynamicNameCriterion(GTIngredientList owner, String values) {
        super(owner, 1);
        
        NamedObj container = owner.getOwner().getContainer();
        _name = new PtolemyExpressionString(container);
        setValues(values);
    }

    /** Get the array of elements defined in this GTIngredient.
     *
     *  @return The array of elements.
     */
    public GTIngredientElement[] getElements() {
        return _ELEMENTS;
    }

    /** Get the value of the index-th elements.
     *
     *  @param index The index.
     *  @return The value.
     *  @see #setValue(int, Object)
     */
    public Object getValue(int index) {
        switch (index) {
        case 0:
            return _name;
        default:
            return null;
        }
    }

    /** Get a string that describes the values of all the elements.
     *
     *  @return A string that describes the values of all the elements.
     *  @see #setValues(String)
     */
    public String getValues() {
        StringBuffer buffer = new StringBuffer();
        _encodeStringField(buffer, 0, _name.get());
        return buffer.toString();
    }

    /** Test whether the given object in the host model matches the object in
     *  the pattern that has this criterion.
     *
     *  @param object The object.
     *  @return true if the object matches.
     */
    public boolean match(NamedObj object) {
        try {
            String name = ((StringToken) _name.getToken()).stringValue();
            return name.equals(object.getName());
        } catch (IllegalActionException e) {
            return false;
        }
    }

    /** Set the value of the index-th element.
     *
     *  @param index The index.
     *  @param value The value.
     *  @see #getValue(int)
     */
    public void setValue(int index, Object value) {
        switch (index) {
        case 0:
            _name.set((String) value);
            break;
        }
    }

    /** Set the values of all the elements with a string that describes them.
     *
     *  @param values A string that describes the new values of all the
     *   elements.
     *  @see #getValues()
     */
    public void setValues(String values) {
        FieldIterator fieldIterator = new FieldIterator(values);
        _name.set(_decodeStringField(0, fieldIterator));
    }

    /** Validate the enablements and values of all the elements.
     *
     *  @exception ValidationException If some elements are invalid.
     */
    public void validate() throws ValidationException {
        if (_name.get().equals("")) {
            throw new ValidationException("Name must not be empty.");
        }
    }

    /** The elements.
     */
    private static final CriterionElement[] _ELEMENTS = {
            new StringCriterionElement("name", false, false, true) };

    /** Value of the name element.
     */
    private PtolemyExpressionString _name;
}