/*
 * Copyright (c) "Neo4j"
 * Neo4j Sweden AB [http://neo4j.com]
 *
 * This file is part of Neo4j.
 *
 * Neo4j is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.neo4j.consistency.checker;

import org.neo4j.kernel.impl.store.record.RelationshipRecord;

/**
 * Means of parameterizing selection of {@link RelationshipRecord} pointers.
 */
public enum NodeLink {
    SOURCE {
        @Override
        public void setPrevRel(RelationshipRecord record, long other) {
            record.setFirstPrevRel(other);
        }

        @Override
        public void setNextRel(RelationshipRecord record, long other) {
            record.setFirstNextRel(other);
        }

        @Override
        public long getPrevRel(RelationshipRecord relationship) {
            return relationship.getFirstPrevRel();
        }

        @Override
        public long getNextRel(RelationshipRecord relationship) {
            return relationship.getFirstNextRel();
        }

        @Override
        public void setNode(RelationshipRecord relationship, long nodeId) {
            relationship.setFirstNode(nodeId);
        }
    },
    TARGET {
        @Override
        public void setPrevRel(RelationshipRecord record, long other) {
            record.setSecondPrevRel(other);
        }

        @Override
        public void setNextRel(RelationshipRecord record, long other) {
            record.setSecondNextRel(other);
        }

        @Override
        public long getPrevRel(RelationshipRecord relationship) {
            return relationship.getSecondPrevRel();
        }

        @Override
        public long getNextRel(RelationshipRecord relationship) {
            return relationship.getSecondNextRel();
        }

        @Override
        public void setNode(RelationshipRecord relationship, long nodeId) {
            relationship.setSecondNode(nodeId);
        }
    };

    public static NodeLink select(RelationshipRecord record, long node) {
        if (record.getFirstNode() == node) {
            return SOURCE;
        }
        if (record.getSecondNode() == node) {
            return TARGET;
        }
        return null;
    }

    public abstract void setPrevRel(RelationshipRecord record, long other);

    public abstract void setNextRel(RelationshipRecord record, long other);

    public abstract long getPrevRel(RelationshipRecord relationship);

    public abstract long getNextRel(RelationshipRecord relationship);

    public abstract void setNode(RelationshipRecord relationship, long nodeId);
}
