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/*
 * Copyright (c) "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 apoc.algo;

import static apoc.algo.PathFinding.buildPathExpander;

import apoc.Extended;
import apoc.result.WeightedPathResult;
import java.util.List;
import java.util.Map;
import java.util.stream.Stream;
import org.neo4j.graphalgo.BasicEvaluationContext;
import org.neo4j.graphalgo.CommonEvaluators;
import org.neo4j.graphalgo.GraphAlgoFactory;
import org.neo4j.graphalgo.PathFinder;
import org.neo4j.graphalgo.WeightedPath;
import org.neo4j.graphdb.GraphDatabaseService;
import org.neo4j.graphdb.Node;
import org.neo4j.graphdb.Transaction;
import org.neo4j.procedure.Context;
import org.neo4j.procedure.Description;
import org.neo4j.procedure.Name;
import org.neo4j.procedure.Procedure;

@Extended
public class PathFindingFull {

    @Context
    public GraphDatabaseService db;

    @Context
    public Transaction tx;

    @Procedure
    @Description(
            "apoc.algo.aStarWithPoint(startNode, endNode, 'relTypesAndDirs', 'distance','pointProp') - "
                    + "equivalent to apoc.algo.aStar but accept a Point type as a pointProperty instead of Number types as latitude and longitude properties")
    public Stream aStarWithPoint(
            @Name("startNode") Node startNode,
            @Name("endNode") Node endNode,
            @Name("relationshipTypesAndDirections") String relTypesAndDirs,
            @Name("weightPropertyName") String weightPropertyName,
            @Name("pointPropertyName") String pointPropertyName) {

        PathFinder algo = GraphAlgoFactory.aStar(
                new BasicEvaluationContext(tx, db),
                buildPathExpander(relTypesAndDirs),
                CommonEvaluators.doubleCostEvaluator(weightPropertyName),
                new PathFinding.GeoEstimateEvaluatorPointCustom(pointPropertyName));
        return WeightedPathResult.streamWeightedPathResult(startNode, endNode, algo);
    }

    @Procedure
    @Description(
            "apoc.algo.travellingSalesman(nodes,  $config) - resolve travelling salesman problem via simulated annealing algo")
    public Stream travellingSalesman(
            @Name("startNode") List nodes,
            @Name(value = "config", defaultValue = "{}") Map config) {
        if (nodes.isEmpty()) {
            throw new RuntimeException("The nodes parameter must have at least 3 nodes");
        }
        TravellingSalesman.Config conf = new TravellingSalesman.Config(config);
        return Stream.of(TravellingSalesman.Algo.simulateAnnealing(nodes, conf));
    }
}