/*
 * Copyright 2005 The Apache Software Foundation
 *
 * 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 org.apache.commons.net.ftp;

import junit.framework.TestCase;
import java.io.IOException;
import java.net.SocketException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Comparator;
import java.util.Iterator;
import java.util.TreeSet;

/*
 * This test was contributed in a different form by W. McDonald Buck
 * of Boulder, Colorado, to help fix some bugs with the FTPClientConfig
 * in a real world setting.  It is a perfect functional test for the
 * Time Zone functionality of FTPClientConfig.
 * 
 * A publicly accessible FTP server at the US National Oceanographic and
 * Atmospheric Adminstration houses a directory which contains 
 * 300 files, named sn.0000 to sn.0300. Every ten minutes or so 
 * the next file in sequence is rewritten with new data. Thus the directory 
 * contains observations for more than 24 hours of data.  Since the server
 * has its clock set to GMT this is an excellent functional test for any
 * machine in a different time zone. 
 * 
 * Noteworthy is the fact that the ftp routines in some web browsers don't 
 * work as well as this.  They can't, since they have no way of knowing the 
 * server's time zone.  Depending on the local machine's position relative 
 * to GMT and the time of day, the browsers may decide that a timestamp 
 * would be in the  future if given the current year, so they assume the 
 * year to be  last year.  This illustrates the value of FTPClientConfig's 
 * time zone functionality.
 */

public class FTPClientConfigFunctionalTest extends TestCase {

    private FTPClient FTP = new FTPClient(); 
    private FTPClientConfig FTPConf; 


    /**
     * 
     */
    public FTPClientConfigFunctionalTest() {
        super();

	}

    /* 
     * @throws java.lang.Exception
     */
    protected void setUp() throws Exception {
        super.setUp();
	    FTPConf = new FTPClientConfig(FTPClientConfig.SYST_UNIX);
	    FTPConf.setServerTimeZoneId("GMT"); 
	    FTP.configure(FTPConf); 
        try {
            FTP.connect("tgftp.nws.noaa.gov");
            FTP.login("anonymous","testing@apache.org");
            FTP.changeWorkingDirectory("SL.us008001/DF.an/DC.sflnd/DS.metar");
            FTP.enterLocalPassiveMode();
        } catch (SocketException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    /* 
     * @throws java.lang.Exception
     */
    protected void tearDown() throws Exception {
        FTP.disconnect();
        super.tearDown();
    }
    /**
     * @param arg0
     */
    public FTPClientConfigFunctionalTest(String arg0) {
        super(arg0);
    }

	
    private TreeSet getSortedList(FTPFile[] files) {
        // create a TreeSet which will sort each element
        // as it is added.
        TreeSet sorted = new TreeSet(new Comparator() {

            public int compare(Object o1, Object o2) {
                FTPFile f1 = (FTPFile) o1;
                FTPFile f2 = (FTPFile) o2;
                return f1.getTimestamp().getTime().compareTo(f2.getTimestamp().getTime());
            }
            
        });
        
         
        for (int i=0; i < files.length; i++) {
			// The directory contains a few additional files at the beginning
			// which aren't in the series we want. The series we want consists
			// of files named sn.dddd. This adjusts the file list to get rid 
			// of the uninteresting ones. 
            if (files[i].getName().startsWith("sn")) {
                sorted.add(files[i]);
            }    
        }
        return sorted;
    }

	
    public static void main(String[] args) {
        FTPClientConfigFunctionalTest F = new FTPClientConfigFunctionalTest();
    }
    
    public void testTimeZoneFunctionality() throws Exception {
        java.util.Date now = new java.util.Date();
        FTPFile[] files = FTP.listFiles();
        TreeSet sorted = getSortedList(files);
        //SimpleDateFormat sdf = new SimpleDateFormat("MM/dd/yyyy HH:mm z" );
        FTPFile lastfile = null;
        FTPFile firstfile = null;
        for (Iterator it = sorted.iterator(); it.hasNext();) {
            FTPFile thisfile = (FTPFile) it.next();
            if (firstfile == null) {
                firstfile = thisfile;
            }
            //System.out.println(sdf.format(thisfile.getTimestamp().getTime()) 
            //        + " " +thisfile.getName());
            if (lastfile != null) {
                // verify that the list is sorted earliest to latest.
                assertTrue(lastfile.getTimestamp()
                        .before(thisfile.getTimestamp()));
            }
            lastfile = thisfile;
        }
        
        // test that notwithstanding any time zone differences, the newest file
        // is older than now.
        assertTrue(lastfile.getTimestamp().getTime().before(now));
        Calendar first = firstfile.getTimestamp();

        // test that the oldest is less than two days older than the newest 
        // and, in particular, that no files have been considered "future" 
        // by the parser and therefore been relegated to the same date a 
        // year ago.
        first.add(Calendar.DATE, 2);
        assertTrue(lastfile.getTimestamp().before(first));

    }
}