/*
 * Copyright (C) 2009 The Android Open Source Project
 *
 * 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 com.android.camera;

import android.location.Address;
import android.location.Geocoder;
import android.os.AsyncTask;
import android.util.Log;

import java.io.IOException;
import java.util.List;

/**
 * A asynchronous task which does reverse geocoding.
 *
 * <p>Because it may take a long time to return, we put it in an AsyncTask.
 * The input is latitude and longitude, and the output is a descriptive string
 * for the specified location. The result is passed to a callback.
 */
public class ReverseGeocoderTask extends AsyncTask<Void, Void, String> {
    private static final String TAG = "ReverseGeocoder";

    /**
     * A callback to be invoked when the reverse geocoding task is done.
     */
    public static interface Callback {
        public void onComplete(String location);
    }

    private Geocoder mGeocoder;
    private float mLat;
    private float mLng;
    private Callback mCallback;

    public ReverseGeocoderTask(Geocoder geocoder, float[] latlng,
            Callback callback) {
        mGeocoder = geocoder;
        mLat = latlng[0];
        mLng = latlng[1];
        mCallback = callback;
    }

    @Override
    protected String doInBackground(Void... params) {
        String value = MenuHelper.EMPTY_STRING;
        try {
            List<Address> address = mGeocoder.getFromLocation(mLat, mLng, 1);
            StringBuilder sb = new StringBuilder();
            for (Address addr : address) {
                int index = addr.getMaxAddressLineIndex();
                sb.append(addr.getAddressLine(index));
            }
            value = sb.toString();
        } catch (IOException ex) {
            value = MenuHelper.EMPTY_STRING;
            Log.e(TAG, "Geocoder exception: ", ex);
        } catch (RuntimeException ex) {
            value = MenuHelper.EMPTY_STRING;
            Log.e(TAG, "Geocoder exception: ", ex);
        }
        return value;
    }

    @Override
    protected void onPostExecute(String location) {
        mCallback.onComplete(location);
    }
}