/*
 * 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.kernel.impl.traversal;

import org.neo4j.graphdb.Node;
import org.neo4j.graphdb.PathExpander;
import org.neo4j.graphdb.Relationship;
import org.neo4j.graphdb.traversal.InitialBranchState;
import org.neo4j.graphdb.traversal.TraversalBranch;
import org.neo4j.graphdb.traversal.TraversalContext;

class StartNodeTraversalBranch extends TraversalBranchWithState {
    private final InitialBranchState initialState;

    StartNodeTraversalBranch(
            TraversalContext context, TraversalBranch parent, Node source, InitialBranchState initialState) {
        super(parent, source, initialState);
        this.initialState = initialState;
        evaluate(context);
        context.isUniqueFirst(this);
    }

    @Override
    public TraversalBranch next(PathExpander expander, TraversalContext metadata) {
        if (!hasExpandedRelationships()) {
            expandRelationships(expander);
            return this;
        }
        return super.next(expander, metadata);
    }

    @Override
    protected TraversalBranch newNextBranch(Node node, Relationship relationship) {
        return initialState != InitialBranchState.NO_STATE
                ? new TraversalBranchWithState(this, 1, node, relationship, stateForChildren)
                : new TraversalBranchImpl(this, 1, node, relationship);
    }
}
