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/*
 *  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.reader.dem;

import com.graphhopper.storage.DAType;

/**
 * @author Peter Karich
 */
public interface ElevationProvider {
    ElevationProvider NOOP = new ElevationProvider() {
        @Override
        public double getEle(double lat, double lon) {
            return Double.NaN;
        }

        @Override
        public ElevationProvider setBaseURL(String baseURL) {
            return this;
        }

        @Override
        public ElevationProvider setDAType(DAType daType) {
            return this;
        }

        @Override
        public void release() {
        }

        @Override
        public void setAutoRemoveTemporaryFiles(boolean autoRemoveTemporary) {
        }

        @Override
        public void setInterpolate(boolean interpolate) {
        }

        @Override
        public boolean getInterpolate() {
            return false;
        }
    };

    /**
     * @return returns the height in meters or Double.NaN if invalid
     */
    double getEle(double lat, double lon);

    /**
     * Specifies the service URL where to download the elevation data. An empty string should set it
     * to the default URL. Default is a provider-dependent URL which should work out of the box.
     */
    ElevationProvider setBaseURL(String baseURL);

    /**
     * Set to true if you have a small area and need high speed access. Default is DAType.MMAP
     */
    ElevationProvider setDAType(DAType daType);

    /**
     * Configuration option to use bilinear interpolation to find the elevation at a point from the
     * surrounding elevation points. Has only an effect if called before the first getEle call.
     * Turned off by default.
     */
    void setInterpolate(boolean interpolate);

    /**
     * Returns true if bilinear interpolation is enabled.
     */
    boolean getInterpolate();

    /**
     * Release resources.
     */
    void release();

    /**
     * Creating temporary files can take a long time as we need to unpack them as well as to fill
     * our DataAccess object, so this option can be used to disable the default clear mechanism via
     * specifying 'false'.
     */
    void setAutoRemoveTemporaryFiles(boolean autoRemoveTemporary);
}