/*******************************************************************************
 * Copyright (c) 2007, 2010 Association for Decentralized Information Management
 * in Industry THTH ry.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     VTT Technical Research Centre of Finland - initial API and implementation
 *******************************************************************************/
package org.simantics.db.tests.api.readGraph.adapt;

import org.junit.Before;
import org.junit.Test;
import org.simantics.db.AsyncReadGraph;
import org.simantics.db.ReadGraph;
import org.simantics.db.Resource;
import org.simantics.db.Session;
import org.simantics.db.WriteGraph;
import org.simantics.db.common.request.ResourceAsyncRead;
import org.simantics.db.common.request.WriteRequest;
import org.simantics.db.exception.AdaptionException;
import org.simantics.db.exception.DatabaseException;
import org.simantics.db.procedure.AsyncProcedure;
import org.simantics.db.request.Read;
import org.simantics.db.services.GlobalServiceInitializer;
import org.simantics.db.testing.base.ExistingDatabaseTest;
import org.simantics.layer0.Layer0;

/**
 * Checks that {@link ReadGraph#adapt(org.simantics.db.Resource, Class)},
 * {@link ReadGraph#adaptUnique(org.simantics.db.Resource, Class)},
 * <code>AsyncReadGraph.forAdapted</code> fail as expected.
 * 
 * <p>
 * Regression test for https://www.simulationsite.net/trac/simantics/ticket/617
 * 
 * @author Tuukka Lehtonen
 */
public class AdaptionFailureTest extends ExistingDatabaseTest {

    @Override
    @Before
    public void setUp() throws Exception {
        super.setUp();
        new GlobalServiceInitializer().initialize(getSession());
    }

    private Resource writeTypeless(Session session) throws DatabaseException {
        final Resource[] typeless = { null };
        session.syncRequest(new WriteRequest() {
            @Override
            public void perform(WriteGraph graph) throws DatabaseException {
                Layer0 l0 = Layer0.getInstance(graph);
                Resource tless = graph.newResource();
                Resource name = graph.newResource();
                graph.claim(name, l0.InstanceOf, null, l0.String);
                graph.claimValue(name, "A Typeless Resource");
                graph.claim(tless, l0.HasName, name);
                typeless[0] = tless;
            }
        });
        return typeless[0];
    }

    static abstract class Adapter {
        String name;

        public Adapter(String name) {
            this.name = name;
        }

        public abstract <T> T adapt(ReadGraph graph, Resource r, Class<T> clazz) throws DatabaseException;

        @Override
        public String toString() {
            return name;
        }
    }

    private void adaptTester(final Adapter adapter) throws DatabaseException {
        final Session session = getSession();
        final Resource typeless = writeTypeless(session);
        try {
            String s = session.syncRequest(new Read<String>() {
                @Override
                public String perform(ReadGraph graph) throws DatabaseException {
                    try {
                        return adapter.adapt(graph, typeless, String.class);
                    } catch (AdaptionException e) {
                        throw e;
                    } catch (DatabaseException e) {
                        throw new DatabaseException("AdaptionException expected, got " + e, e);
                    }
                }
            });

            if (s == null)
                fail(adapter + " must never return null");
        } catch (AdaptionException e) {
            // Failure with AdaptionException is expected
            if (DEBUG)
                System.out.println("Expected failure message: " + e.getMessage());
        }
    }

    @Test
    public void testAdapt() throws DatabaseException{
        adaptTester(new Adapter("ReadGraph.adapt") {
            @Override
            public <T> T adapt(ReadGraph graph, Resource resource, Class<T> clazz) throws DatabaseException {
                return graph.adapt(resource, clazz);
            }
        });
    }

    @Test
    public void testAdaptUnique() throws DatabaseException{
        adaptTester(new Adapter("ReadGraph.adaptUnique") {
            @Override
            public <T> T adapt(ReadGraph graph, Resource resource, Class<T> clazz) throws DatabaseException {
                return graph.adaptUnique(resource, clazz);
            }
        });
    }

    @Test
    public void testforAdapted() throws DatabaseException{
        adaptTester(new Adapter("AsyncReadGraph.forAdapted") {
            @Override
            public <T> T adapt(ReadGraph graph, Resource resource, final Class<T> clazz) throws DatabaseException {
                return graph.syncRequest(new ResourceAsyncRead<T>(resource) {
                    @Override
                    public void perform(AsyncReadGraph graph, AsyncProcedure<T> procedure) {
                        graph.forAdapted(resource, clazz, procedure);
                    }
                });
            }
        });
    }

    @Test
    public void testforUniqueAdapted() throws DatabaseException{
        adaptTester(new Adapter("AsyncReadGraph.forUniqueAdapted") {
            @Override
            public <T> T adapt(ReadGraph graph, Resource resource, final Class<T> clazz) throws DatabaseException {
                return graph.syncRequest(new ResourceAsyncRead<T>(resource) {
                    @Override
                    public void perform(AsyncReadGraph graph, AsyncProcedure<T> procedure) {
                        graph.forUniqueAdapted(resource, clazz, procedure);
                    }
                });
            }
        });
    }

}