/*******************************************************************************
 * Copyright (c) 2007, 2011 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.issues.common;

import java.util.Set;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;

import org.simantics.db.AsyncReadGraph;
import org.simantics.db.Resource;
import org.simantics.db.common.request.TernaryAsyncRead;
import org.simantics.db.procedure.AsyncMultiProcedure;
import org.simantics.db.procedure.AsyncProcedure;
import org.simantics.issues.Severity;
import org.simantics.issues.ontology.IssueResource;

/**
 * @author Tuukka Lehtonen
 */
public class MaxIssueSeverityRecursive extends TernaryAsyncRead<Resource, Resource, Set<Resource>, Severity> {

    public MaxIssueSeverityRecursive(Resource resource, Resource childRelation, Set<Resource> typesToRecurse) {
        super(resource, childRelation, typesToRecurse);
    }
    
    @Override
    public void perform(AsyncReadGraph graph, final AsyncProcedure<Severity> procedure) {

        IssueResource ISSUE = graph.getService(IssueResource.class);

        AtomicInteger issues = new AtomicInteger();
        AtomicBoolean excepted = new AtomicBoolean(false);

        graph.forEachObject(parameter, ISSUE.Issue_HasContext_Inverse, new AsyncMultiProcedure<Resource>() {
            @Override
            public void execute(AsyncReadGraph graph, Resource result) {
                issues.incrementAndGet();
            }
            @Override
            public void finished(AsyncReadGraph graph) {
            
            }
            @Override
            public void exception(AsyncReadGraph graph, Throwable throwable) {
                if(excepted.compareAndSet(false, true))
                    procedure.exception(graph, throwable);
            }
        });

        graph.forEachObject(parameter, ISSUE.Issue_ContextList_Element_Inverse, new AsyncMultiProcedure<Resource>() {
            @Override
            public void execute(AsyncReadGraph graph, Resource result) {
                issues.incrementAndGet();
            }
            @Override
            public void finished(AsyncReadGraph graph) {
            
            }
            @Override
            public void exception(AsyncReadGraph graph, Throwable throwable) {
                if(excepted.compareAndSet(false, true))
                  procedure.exception(graph, throwable);
            }
        });
        
        if(excepted.get()) return;

        if (issues.get() == 0) {
            // This content does not have directly attached issues, try to look
            // for some in the child components.
            graph.asyncRequest(new ChildMaxIssueSeverity(parameter, parameter2, parameter3), procedure);
        } else {
            // Try local issues first
            graph.asyncRequest(new MaxIssueSeveritySingle(parameter), new AsyncProcedure<Severity>() {
                @Override
                public void execute(AsyncReadGraph graph, Severity maxSeverity) {
                    if (maxSeverity == null)
                        // No severity for local issues, try children next.
                        graph.asyncRequest(new ChildMaxIssueSeverity(parameter, parameter2, parameter3), procedure);
                    else
                        procedure.execute(graph, maxSeverity);
                }
                @Override
                public void exception(AsyncReadGraph graph, Throwable throwable) {
                    if(excepted.compareAndSet(false, true))
                      procedure.exception(graph, throwable);
                }
            });
        }
    }

}