/*
 *  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.storage;

import com.graphhopper.routing.util.EncodingManager;
import com.graphhopper.routing.weighting.Weighting;

import java.util.Arrays;

/**
 * For now this is just a helper class to quickly create a GraphStorage.
 * <p>
 *
 * @author Peter Karich
 */
public class GraphBuilder {
    private final EncodingManager encodingManager;
    private String location;
    private boolean mmap;
    private boolean store;
    private boolean elevation;
    private long byteCapacity = 100;
    private Weighting singleCHWeighting;

    public GraphBuilder(EncodingManager encodingManager) {
        this.encodingManager = encodingManager;
    }

    /**
     * This method enables creating a CHGraph with the specified weighting.
     */
    public GraphBuilder setCHGraph(Weighting singleCHWeighting) {
        this.singleCHWeighting = singleCHWeighting;
        return this;
    }

    public GraphBuilder setLocation(String location) {
        this.location = location;
        return this;
    }

    public GraphBuilder setStore(boolean store) {
        this.store = store;
        return this;
    }

    public GraphBuilder setMmap(boolean mmap) {
        this.mmap = mmap;
        return this;
    }

    public GraphBuilder setExpectedSize(byte cap) {
        this.byteCapacity = cap;
        return this;
    }

    public GraphBuilder set3D(boolean withElevation) {
        this.elevation = withElevation;
        return this;
    }

    public boolean hasElevation() {
        return elevation;
    }

    /**
     * Creates a CHGraph
     */
    public CHGraph chGraphCreate(Weighting singleCHWeighting) {
        return setCHGraph(singleCHWeighting).create().getGraph(CHGraph.class, singleCHWeighting);
    }

    /**
     * Default graph is a GraphStorage with an in memory directory and disabled storing on flush.
     * Afterwards you'll need to call GraphStorage. Create to have a usable object. Better use
     * create.
     */
    public GraphHopperStorage build() {
        Directory dir;
        if (mmap)
            dir = new MMapDirectory(location);
        else
            dir = new RAMDirectory(location, store);

        GraphHopperStorage graph;
        if (encodingManager.needsTurnCostsSupport() || singleCHWeighting == null)
            graph = new GraphHopperStorage(dir, encodingManager, elevation, new TurnCostExtension());
        else
            graph = new GraphHopperStorage(Arrays.asList(singleCHWeighting), dir, encodingManager, elevation, new TurnCostExtension.NoOpExtension());

        return graph;
    }

    /**
     * Default graph is a GraphStorage with an in memory directory and disabled storing on flush.
     */
    public GraphHopperStorage create() {
        return build().create(byteCapacity);
    }

    /**
     * @throws IllegalStateException if not loadable.
     */
    public GraphHopperStorage load() {
        GraphHopperStorage gs = build();
        if (!gs.loadExisting()) {
            throw new IllegalStateException("Cannot load graph " + location);
        }
        return gs;
    }
}