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Neo4j-OGM's internal Api for connecting different transports.
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/*
 * Copyright (c) 2002-2024 "Neo4j,"
 * Neo4j Sweden AB [http://neo4j.com]
 *
 * This file is part of Neo4j.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.neo4j.ogm.result.adapter;

import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.neo4j.ogm.model.GraphModel;
import org.neo4j.ogm.response.model.DefaultGraphModel;
import org.neo4j.ogm.response.model.NodeModel;
import org.neo4j.ogm.response.model.RelationshipModel;

/**
 * This adapter will transform an embedded response into a json response
 *
 * @author Vince Bickers
 * @author Luanne Misquitta
 * @author Michael J. Simons
 */
public abstract class GraphModelAdapter extends BaseAdapter implements ResultAdapter, GraphModel> {

    /**
     * Parses a row from the result object and transforms it into a GraphModel
     *
     * @param data the data to transform, given as a map
     * @return the data transformed to an {@link GraphModel}
     */
    @Override
    public GraphModel adapt(Map data) {

        // These two sets keep track of which nodes and edges have already been built, so we don't redundantly
        // write the same node or relationship entity many times.
        final Set nodeIdentities = new HashSet<>();
        final Set edgeIdentities = new HashSet<>();

        DefaultGraphModel graphModel = new DefaultGraphModel();

        for (Map.Entry mapEntry : data.entrySet()) {
            final Object value = mapEntry.getValue();

            String resultKey = mapEntry.getKey();
            boolean generatedNodes = ResultAdapter.describesGeneratedNode(resultKey);

            adaptInternal(nodeIdentities, edgeIdentities, graphModel, value, generatedNodes);
        }

        return graphModel;
    }

    private void adaptInternal(Set nodeIdentities, Set edgeIdentities, DefaultGraphModel graphModel,
        Object value, boolean generatedNodes) {
        if (isPath(value)) {
            buildPath(value, graphModel, nodeIdentities, edgeIdentities, generatedNodes);
        } else if (isNode(value)) {
            buildNode(value, graphModel, nodeIdentities, generatedNodes);
        } else if (isRelationship(value)) {
            buildRelationship(value, graphModel, edgeIdentities);
        } else if (value instanceof Iterable) {
            Iterable collection = (Iterable) value;
            for (Object element : collection) {
                adaptInternal(nodeIdentities, edgeIdentities, graphModel, element, generatedNodes);
            }
        }
    }

    void buildPath(Object path, DefaultGraphModel graphModel, Set nodeIdentities, Set edgeIdentities,
        boolean generatedNodes) {

        Iterator