com.nadmm.airports.library.LibraryService.java Source code

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Here is the source code for com.nadmm.airports.library.LibraryService.java

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/*
 * FlightIntel for Pilots
 *
 * Copyright 2012 Nadeem Hasan <nhasan@nadmm.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>. 
 */

package com.nadmm.airports.library;

import java.io.File;
import java.net.URI;
import java.util.ArrayList;
import java.util.zip.GZIPInputStream;

import org.apache.http.client.HttpClient;
import org.apache.http.client.utils.URIUtils;

import android.app.IntentService;
import android.content.Intent;
import android.os.Bundle;
import android.os.ResultReceiver;
import android.support.v4.content.LocalBroadcastManager;

import com.nadmm.airports.utils.NetworkUtils;
import com.nadmm.airports.utils.SystemUtils;
import com.nadmm.airports.utils.UiUtils;

public class LibraryService extends IntentService {

    private static final String SERVICE_NAME = "library";

    public static final String LIBRARY_HOST = "commondatastorage.googleapis.com";
    public static final String LIBRARY_PATH = "/flightintel/library";
    public static final String ACTION_GET_BOOK = "flightintel.library.action.GET_BOOK";
    public static final String ACTION_DELETE_BOOK = "flightintel.library.action.DELETE_BOOK";
    public static final String ACTION_CHECK_BOOKS = "flightintel.library.action.CHECK_BOOKS";
    public static final String ACTION_DOWNLOAD_PROGRESS = "flightintel.library.action.PROGRESS";
    public static final String CATEGORY = "CATEGORY";
    public static final String BOOK_NAME = "BOOK_NAME";
    public static final String BOOK_NAMES = "BOOK_NAMES";
    public static final String PDF_PATH = "PDF_PATH";

    private final File mDataDir;
    private final HttpClient mHttpClient;

    public LibraryService() {
        super(SERVICE_NAME);

        mHttpClient = NetworkUtils.getHttpClient();
        mDataDir = SystemUtils.getExternalDir(SERVICE_NAME);
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        String action = intent.getAction();
        if (action.equals(ACTION_CHECK_BOOKS)) {
            checkBooks(intent);
        } else if (action.equals(ACTION_GET_BOOK)) {
            getBook(intent);
        } else if (action.equals(ACTION_DELETE_BOOK)) {
            deleteBook(intent);
        }
    }

    private void checkBooks(Intent intent) {
        String category = intent.getStringExtra(CATEGORY);
        ArrayList<String> books = intent.getStringArrayListExtra(BOOK_NAMES);

        cleanupBooks(category, books);

        File categoryDir = getCategoryDir(category);
        for (String book : books) {
            File pdfFile = new File(categoryDir, book);
            sendResult(intent.getAction(), category, pdfFile);
        }
    }

    private void getBook(Intent intent) {
        String category = intent.getStringExtra(CATEGORY);
        String book = intent.getStringExtra(BOOK_NAME);
        File categoryDir = getCategoryDir(category);

        File pdfFile = new File(categoryDir, book);
        if (!pdfFile.exists()) {
            fetch(category, pdfFile);
        }

        sendResult(intent.getAction(), category, pdfFile);
    }

    private void deleteBook(Intent intent) {
        String category = intent.getStringExtra(CATEGORY);
        String book = intent.getStringExtra(BOOK_NAME);
        File categoryDir = getCategoryDir(category);

        File pdfFile = new File(categoryDir, book);
        if (pdfFile.exists()) {
            pdfFile.delete();
        }

        sendResult(ACTION_CHECK_BOOKS, category, pdfFile);
    }

    private boolean fetch(String category, File pdfFile) {
        try {
            String path = LIBRARY_PATH + "/" + category + "/" + pdfFile.getName() + ".gz";
            URI uri = URIUtils.createURI("http", LIBRARY_HOST, 80, path, null, null);

            ProgressReceiver receiver = new ProgressReceiver();
            Bundle result = new Bundle();
            result.putString(NetworkUtils.CONTENT_NAME, pdfFile.getName());
            result.putString(CATEGORY, category);

            return NetworkUtils.doHttpGet(this, mHttpClient, uri, pdfFile, receiver, result, GZIPInputStream.class);
        } catch (Exception e) {
            UiUtils.showToast(this, e.getMessage());
        }
        return false;
    }

    protected void sendResult(String action, String category, File pdfFile) {
        Intent result = new Intent(action);
        result.putExtra(CATEGORY, category);
        result.putExtra(BOOK_NAME, pdfFile.getName());
        if (pdfFile.exists()) {
            result.putExtra(PDF_PATH, pdfFile.getAbsolutePath());
        }
        LocalBroadcastManager bm = LocalBroadcastManager.getInstance(this);
        bm.sendBroadcast(result);
    }

    private void cleanupBooks(String category, ArrayList<String> books) {
        // Delete all books that are no longer in the library list for a category
        File categoryDir = getCategoryDir(category);
        File[] list = categoryDir.listFiles();
        if (list != null) {
            for (File pdfFile : list) {
                if (!books.contains(pdfFile.getName())) {
                    pdfFile.delete();
                }
            }
        }
    }

    private File getCategoryDir(String category) {
        File categoryDir = new File(mDataDir, category);
        if (!categoryDir.exists()) {
            categoryDir.mkdirs();
        }
        return categoryDir;
    }

    protected void handleProgress(int resultCode, Bundle resultData) {
        Intent intent = new Intent(ACTION_DOWNLOAD_PROGRESS);
        intent.putExtras(resultData);
        LocalBroadcastManager bm = LocalBroadcastManager.getInstance(this);
        bm.sendBroadcast(intent);
    }

    private class ProgressReceiver extends ResultReceiver {

        public ProgressReceiver() {
            super(null);
        }

        @Override
        public void send(int resultCode, Bundle resultData) {
            // We want to handle the result in the same thread synchronously
            handleProgress(resultCode, resultData);
        }

    }

}