/*******************************************************************************
 * Copyright (c) 2012 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.modeling.typicals.rules;

import java.util.Set;

import gnu.trove.set.hash.THashSet;

import org.simantics.db.Resource;
import org.simantics.db.WriteGraph;
import org.simantics.db.common.utils.NameUtils;
import org.simantics.db.exception.DatabaseException;
import org.simantics.diagram.flag.FlagUtil;
import org.simantics.diagram.stubs.DiagramResource;
import org.simantics.modeling.typicals.ITypicalSynchronizationRule;
import org.simantics.modeling.typicals.TypicalInfo;
import org.simantics.utils.ui.ErrorLogger;

/**
 * Synchronizes:
 * * joins
 * * flag type
 * * external tag
 * * IO table binding
 * * IO table row index 
 * 
 * @author Tuukka Lehtonen
 */
public enum FlagRule implements ITypicalSynchronizationRule {

    INSTANCE;

    public static FlagRule getInstance() {
        return INSTANCE;
    }

    @Override
    public boolean synchronize(WriteGraph graph, Resource template, Resource instance, TypicalInfo info) throws DatabaseException {
        DiagramResource DIA = DiagramResource.getInstance(graph);

        boolean changed = false;

        boolean result = Properties.synchronizeEnumerationPropertyValue(graph, template, instance, DIA.HasFlagType);
        if(result) info.messageLog.add("\t\t\tflag type");
        changed |= result;
        result = Properties.synchronizeTag(graph, template, instance, DIA.ExternalFlag);
        if(result) info.messageLog.add("\t\t\texternal status");
        changed |= result;
        result = Properties.synchronizePrimitivePropertyValue(graph, template, instance, DIA.Flag_HasIOTableBinding);
        if(result) info.messageLog.add("\t\t\tIO table binding");
        changed |= result;
        result = Properties.synchronizePrimitivePropertyValue(graph, template, instance, DIA.Flag_HasIOTableRowIndex);
        if(result) info.messageLog.add("\t\t\tIO table row");
        changed |= result;
        changed |= synchronizeJoins(graph, template, instance, info);

        return changed;
    }

    public boolean synchronizeJoins(WriteGraph graph, Resource template, Resource instance, TypicalInfo info) throws DatabaseException {
        boolean changed = false;

        Set<Resource> tCounterparts = FlagUtil.getCounterparts(graph, template, new THashSet<Resource>(2));
        Set<Resource> iCounterparts = FlagUtil.getCounterparts(graph, instance, new THashSet<Resource>(2));
        if (tCounterparts.isEmpty() && iCounterparts.isEmpty())
            return false;

        for (Resource tCounterpart : tCounterparts) {
            if (!info.bean.templateElements.contains(tCounterpart)) {
                // Ignore external flag reference in synchronization.
                // The user should not be able to create these at all.
                ErrorLogger.defaultLogWarning("Encountered flag " + NameUtils.getSafeName(graph, template, true)
                        + " in a typical template diagram with an invalid flag reference to correspondence "
                        + NameUtils.getSafeName(graph, tCounterpart, true), new Exception("trace"));
                continue;
            }
            Resource i = info.bean.templateToInstance.get(tCounterpart);
            if (i == null) {
                ErrorLogger.defaultLogError(
                        "Encountered flag " + NameUtils.getSafeName(graph, template, true)
                                + " in a typical template diagram while the instance diagram flag "
                                + NameUtils.getSafeName(graph, instance, true)
                                + " does not contain an element mapped to template flag correspondence "
                                + NameUtils.getSafeName(graph, tCounterpart, true), new Exception("trace"));
                continue;
            }
            if (iCounterparts.remove(i))
                // instance has the similar counterpart as the template
                continue;

            // Instance does not have the same counterpart as the template.
            // Create a new join.
            FlagUtil.join(graph, instance, i);
			info.messageLog.add("\t\t\tsynchronized join " + NameUtils.getSafeName(graph, i));
            changed = true;
        }

        // iCounterparts contains the set of joins that should be severed for
        // the instance flag.
        for (Resource iCounterpart : iCounterparts) {
            FlagUtil.disconnectFlag(graph, instance, iCounterpart);
			info.messageLog.add("\t\t\tdisconnected flag " + NameUtils.getSafeName(graph, iCounterpart));
            changed = true;
        }

        return changed;
    }

}