/*******************************************************************************
 * Copyright (c) 2009, 2018 SAP AG and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v2.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v20.html
 * 
 * Contributors:
 *     SAP AG - initial API and implementation
 ******************************************************************************/
package org.eclipse.ocl.examples.impactanalyzer.instanceScope.unusedEvaluation;

import java.util.Map;
import java.util.Set;

import org.eclipse.emf.common.notify.Notification;
import org.eclipse.emf.common.util.Diagnostic;
import org.eclipse.emf.ecore.EClass;
import org.eclipse.emf.ecore.EClassifier;
import org.eclipse.emf.ecore.EEnumLiteral;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.EOperation;
import org.eclipse.emf.ecore.EPackage;
import org.eclipse.emf.ecore.EParameter;
import org.eclipse.emf.ecore.EStructuralFeature;
import org.eclipse.ocl.AbstractEvaluationVisitor;
import org.eclipse.ocl.Environment;
import org.eclipse.ocl.EvaluationEnvironment;
import org.eclipse.ocl.EvaluationHaltedException;
import org.eclipse.ocl.ecore.CallOperationAction;
import org.eclipse.ocl.ecore.Constraint;
import org.eclipse.ocl.ecore.SendSignalAction;
import org.eclipse.ocl.examples.impactanalyzer.ValueNotFoundException;
import org.eclipse.ocl.examples.impactanalyzer.deltaPropagation.PartialEvaluationVisitorImpl;
import org.eclipse.ocl.examples.impactanalyzer.impl.ImpactAnalyzerPlugin;
import org.eclipse.ocl.expressions.OCLExpression;
import org.eclipse.ocl.expressions.OperationCallExp;
import org.eclipse.ocl.utilities.PredefinedType;


/**
 * In addition to throwing a {@link ValueNotFoundException} as already done by the superclass,
 * this implementation also throws a {@link NoAllInstancesDuringEvaluationForUnusedCheck} exception
 * in case an <code>allInstances()</code> call is to be evaluated.
 * 
 * @author Axel Uhl
 * 
 */
public class PartialEvaluationVisitorImplNoAllInstances extends PartialEvaluationVisitorImpl {
    /**
     * @param atPre
     *            a {@link Notification} object such that an evaluation will be based on the state *before* the notification. For
     *            example, if the notification indicates the removal of a reference from an element <tt>e1</tt> to an element
     *            <tt>e2</tt> across reference <tt>r</tt> then when during partial evaluation <tt>r</tt> is traversed starting
     *            from <tt>e1</tt> then <tt>e2</tt> will show in the results although in the current version of the model it would
     *            not. If <tt>null</tt>, the evaluator will evaluate expressions on the model as is.
     */
    public PartialEvaluationVisitorImplNoAllInstances(
            Environment<EPackage, EClassifier, EOperation, EStructuralFeature, EEnumLiteral, EParameter, EObject, CallOperationAction, SendSignalAction, Constraint, EClass, EObject> env,
            EvaluationEnvironment<EClassifier, EOperation, EStructuralFeature, EClass, EObject> evalEnv,
            Map<? extends EClass, ? extends Set<? extends EObject>> extentMap,
            org.eclipse.ocl.ecore.OCLExpression sourceExpression, Object valueOfSourceExpression, Notification atPre) {
        super(env, evalEnv, extentMap, sourceExpression, valueOfSourceExpression, atPre);
    }

    @Override
    public Object visitOperationCallExp(OperationCallExp<EClassifier, EOperation> oc) {
        if (oc == getSourceExpression()) {
            setSourceExpression(null);
            return getValueOfSourceExpression();
        } else {
            int opCode = oc.getOperationCode();
            if (opCode == PredefinedType.ALL_INSTANCES) {
                throw new NoAllInstancesDuringEvaluationForUnusedCheck();
            }
        }
        return super.visitOperationCallExp(oc);
    }

    /**
     * Does the same as the {@link AbstractEvaluationVisitor} implementation but additionally catches the
     * {@link ValueNotFoundException} and in that case passes on the exception instead of turning it into an <tt>OclInvalid</tt>
     * value.
     * 
     * @param expression
     *            an OCL expression to evaluate
     * 
     * @return the result of the evaluation
     */
    @Override
    public Object visitExpression(OCLExpression<EClassifier> expression) {
        try {
            return expression.accept(getVisitor());
        } catch (EvaluationHaltedException e) {
            // evaluation stopped on demand, propagate further
            throw e;
        } catch (ValueNotFoundException e) {
            throw e;
        } catch (NoAllInstancesDuringEvaluationForUnusedCheck e2) {
            throw e2;
        } catch (RuntimeException e) {
            String msg = e.getLocalizedMessage();
            if (msg == null) {
                msg = "(no message)";
            }
            ImpactAnalyzerPlugin.log(Diagnostic.ERROR, ImpactAnalyzerPlugin.IGNORED_EXCEPTION_WARNING,
                    "Evaluation failed with an exception: " + msg, e);

            // failure to evaluate results in invalid
            return getInvalid();
        }
    }
}