/*******************************************************************************
 * 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.procore.cluster;

import java.util.UUID;

import org.simantics.db.common.utils.Logger;
import org.simantics.db.exception.DatabaseException;
import org.simantics.db.exception.InvalidClusterException;
import org.simantics.db.impl.ClusterBase;
import org.simantics.db.impl.ClusterSupport;
import org.simantics.db.impl.IClusterTable;
import org.simantics.db.impl.Modifier;
import org.simantics.db.service.ClusterCollectorPolicy.CollectorCluster;
import org.simantics.db.service.ClusterUID;
import org.simantics.db.service.ClusteringSupport.Id;

import fi.vtt.simantics.procore.internal.Change;
import fi.vtt.simantics.procore.internal.ClusterChange;
import fi.vtt.simantics.procore.internal.ClusterTable;
import fi.vtt.simantics.procore.internal.SessionImplSocket;

public abstract class ClusterImpl extends ClusterBase implements Modifier, CollectorCluster {
    private static final int LONG_HEADER_SIZE = 7;
    private static final long LONG_HEADER_VERSION = 1;
    protected static ClusterUID checkValidity(long type, long[] longs, int[] ints, byte[] bytes)
    throws InvalidClusterException {
        if (longs.length < LONG_HEADER_SIZE)
            throw new InvalidClusterException("Header size mismatch. Expected=" + ClusterImpl.LONG_HEADER_SIZE + ", got=" + longs.length);
        if (longs[0] != type)
            throw new InvalidClusterException("Type mismatch. Expected=" + type + ", got=" + longs[0]);
        if (longs[1] != ClusterImpl.LONG_HEADER_VERSION)
            throw new InvalidClusterException("Header size mismatch. Expected=" + ClusterImpl.LONG_HEADER_VERSION + ", got=" + longs[1]);
        return ClusterUID.make(longs[2], longs[3]);
    }
    protected static Id getUniqueId(long[] longs) {
        return new IdImpl(new UUID(longs[3], longs[4]));
    }
    static final boolean DEBUG = false;
    // This can be null iff the cluster has been converted to big
    public Change change = new Change();
    public ClusterChange cc;
    public byte[] foreignLookup;
    
    private boolean dirtySizeInBytes = true;
    private long sizeInBytes = 0;
    
    protected ClusterTable clusterTable;
    
    public ClusterImpl(ClusterUID clusterUID, int clusterKey, ClusterSupport support) {
        super(support, clusterUID, clusterKey);
        this.clusterTable = ((SessionImplSocket)support.getSession()).clusterTable;
    }
    
    public static ClusterImpl make(ClusterUID clusterUID, int clusterKey, ClusterSupport support) {
        return new ClusterSmall(clusterUID, clusterKey, support);
    }
    public static ClusterSmall proxy(ClusterUID clusterUID, int clusterKey, long clusterId, ClusterSupport support) {
        if (DEBUG)
            new Exception("Cluster proxy for " + clusterUID).printStackTrace();
        return new ClusterSmall(clusterUID, clusterKey, ((SessionImplSocket)support.getSession()).clusterTable, support);
    }
    public static ClusterImpl make(long[] longs, int[] ints, byte[] bytes, ClusterSupport support, int clusterKey)
    throws DatabaseException {
        if (longs[0] == 0)
            return new ClusterBig(longs, ints, bytes, support, clusterKey);
        else
            return new ClusterSmall(longs, ints, bytes, support, clusterKey);
    }
    public abstract ClusterBig toBig(ClusterSupport support)
    throws DatabaseException;
    
    public abstract void checkDirectReference(int dr)
    throws DatabaseException;

    public abstract void checkForeingIndex(int fi)
    throws DatabaseException;

    public abstract void checkObjectSetReference(int or)
    throws DatabaseException;

//    public boolean virtual = false;
    
    @Override
    public boolean hasVirtual() {
        return clusterTable.hasVirtual(clusterKey);
    }

    @Override
    public void markVirtual() {
        clusterTable.markVirtual(clusterKey);
//        virtual = true;
    }
    
    @Override
    public boolean isWriteOnly() {
        return false;
    }
    @Override
    public boolean isLoaded() {
        return true;
    }
    
    @Override
    public void resized() {
        dirtySizeInBytes = true;
        clusterTable.setDirtySizeInBytes(true);
    }
    
    public long getCachedSize() {
        if(dirtySizeInBytes) {
            try {
                sizeInBytes = getUsedSpace();
                //System.err.println("recomputed size of cluster " + getClusterId() + " => " + sizeInBytes);
            } catch (DatabaseException e) {
                Logger.defaultLogError(e);
            }
            dirtySizeInBytes = false;
        }
        return sizeInBytes;
    }

    protected void calculateModifiedId() {
//        setModifiedId(new IdImpl(UUID.randomUUID()));
    }
    
    @Override
    public IClusterTable getClusterTable() {
        return clusterTable;
    }
}