/*
 *  Licensed to GraphHopper GmbH under one or more contributor
 *  license agreements. See the NOTICE file distributed with this work for 
 *  additional information regarding copyright ownership.
 * 
 *  GraphHopper GmbH licenses this file to you 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 com.graphhopper.routing;

import com.graphhopper.util.NotThreadSafe;

import java.util.List;

/**
 * Calculates the shortest path from the specified node ids. Can be used only once.
 * <p>
 *
 * @author Peter Karich
 */
@NotThreadSafe
public interface RoutingAlgorithm {
    /**
     * Calculates the best path between the specified nodes.
     *
     * @return the path. Call the method found() to make sure that the path is valid.
     */
    Path calcPath(int from, int to);

    /**
     * Calculates multiple possibilities for a path.
     *
     * @see #calcPath(int, int)
     */
    List<Path> calcPaths(int from, int to);

    /**
     * Limit the search to numberOfNodes. See #681
     */
    void setMaxVisitedNodes(int numberOfNodes);

    /**
     * @return name of this algorithm
     */
    String getName();

    /**
     * Returns the visited nodes after searching. Useful for debugging.
     */
    int getVisitedNodes();
}