/*

 * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package sun.net.ftp.impl;

import java.net.*;

import java.io.*;

import java.security.AccessController;

import java.security.PrivilegedAction;

import java.text.DateFormat;

import java.text.ParseException;

import java.text.SimpleDateFormat;

import java.util.ArrayList;

import java.util.Calendar;

import java.util.Date;

import java.util.Iterator;

import java.util.List;

import java.util.TimeZone;

import java.util.Vector;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

import javax.net.ssl.SSLSocket;

import javax.net.ssl.SSLSocketFactory;

import sun.misc.BASE64Decoder;

import sun.misc.BASE64Encoder;

import sun.net.ftp.*;

import sun.util.logging.PlatformLogger;

public class FtpClient extends sun.net.ftp.FtpClient {

    private static int defaultSoTimeout;

    private static int defaultConnectTimeout;

    private static final PlatformLogger logger =

             PlatformLogger.getLogger("sun.net.ftp.FtpClient");

    private Proxy proxy;

    private Socket server;

    private PrintStream out;

    private InputStream in;

    private int readTimeout = -1;

    private int connectTimeout = -1;

    /* Name of encoding to use for output */

    private static String encoding = "ISO8859_1";

    /** remember the ftp server name because we may need it */

    private InetSocketAddress serverAddr;

    private boolean replyPending = false;

    private boolean loggedIn = false;

    private boolean useCrypto = false;

    private SSLSocketFactory sslFact;

    private Socket oldSocket;

    /** Array of strings (usually 1 entry) for the last reply from the server. */

    private Vector<String> serverResponse = new Vector<String>(1);

    /** The last reply code from the ftp daemon. */

    private FtpReplyCode lastReplyCode = null;

    /** Welcome message from the server, if any. */

    private String welcomeMsg;

    private boolean passiveMode = true;

    private TransferType type = TransferType.BINARY;

    private long restartOffset = 0;

    private long lastTransSize = -1; // -1 means 'unknown size'

    private String lastFileName;

    /**

     * Static members used by the parser

     */

    private static String[] patStrings = {

        // drwxr-xr-x  1 user01        ftp   512 Jan 29 23:32 prog

        "([\\-ld](?:[r\\-][w\\-][x\\-]){3})\\s*\\d+ (\\w+)\\s*(\\w+)\\s*(\\d+)\\s*([A-Z][a-z][a-z]\\s*\\d+)\\s*(\\d\\d:\\d\\d)\\s*(\\p{Print}*)",

        // drwxr-xr-x  1 user01        ftp   512 Jan 29 1997 prog

        "([\\-ld](?:[r\\-][w\\-][x\\-]){3})\\s*\\d+ (\\w+)\\s*(\\w+)\\s*(\\d+)\\s*([A-Z][a-z][a-z]\\s*\\d+)\\s*(\\d{4})\\s*(\\p{Print}*)",

        // 04/28/2006  09:12a               3,563 genBuffer.sh

        "(\\d{2}/\\d{2}/\\d{4})\\s*(\\d{2}:\\d{2}[ap])\\s*((?:[0-9,]+)|(?:<DIR>))\\s*(\\p{Graph}*)",

        // 01-29-97    11:32PM <DIR> prog

        "(\\d{2}-\\d{2}-\\d{2})\\s*(\\d{2}:\\d{2}[AP]M)\\s*((?:[0-9,]+)|(?:<DIR>))\\s*(\\p{Graph}*)"

    };

    private static int[][] patternGroups = {

        // 0 - file, 1 - size, 2 - date, 3 - time, 4 - year, 5 - permissions,

        // 6 - user, 7 - group

        {7, 4, 5, 6, 0, 1, 2, 3},

        {7, 4, 5, 0, 6, 1, 2, 3},

        {4, 3, 1, 2, 0, 0, 0, 0},

        {4, 3, 1, 2, 0, 0, 0, 0}};

    private static Pattern[] patterns;

    private static Pattern linkp = Pattern.compile("(\\p{Print}+) \\-\\> (\\p{Print}+)$");

    private DateFormat df = DateFormat.getDateInstance(DateFormat.MEDIUM, java.util.Locale.US);

    static {

        final int vals[] = {0, 0};

        final String encs[] = {null};

        AccessController.doPrivileged(

                new PrivilegedAction<Object>() {

                    public Object run() {

                        vals[0] = Integer.getInteger("sun.net.client.defaultReadTimeout", 0).intValue();

                        vals[1] = Integer.getInteger("sun.net.client.defaultConnectTimeout", 0).intValue();

                        encs[0] = System.getProperty("file.encoding", "ISO8859_1");

                        return null;

                    }

                });

        if (vals[0] == 0) {

            defaultSoTimeout = -1;

        } else {

            defaultSoTimeout = vals[0];

        }

        if (vals[1] == 0) {

            defaultConnectTimeout = -1;

        } else {

            defaultConnectTimeout = vals[1];

        }

        encoding = encs[0];

        try {

            if (!isASCIISuperset(encoding)) {

                encoding = "ISO8859_1";

            }

        } catch (Exception e) {

            encoding = "ISO8859_1";

        }

        patterns = new Pattern[patStrings.length];

        for (int i = 0; i < patStrings.length; i++) {

            patterns[i] = Pattern.compile(patStrings[i]);

        }

    }

    /**

     * Test the named character encoding to verify that it converts ASCII

     * characters correctly. We have to use an ASCII based encoding, or else

     * the NetworkClients will not work correctly in EBCDIC based systems.

     * However, we cannot just use ASCII or ISO8859_1 universally, because in

     * Asian locales, non-ASCII characters may be embedded in otherwise

     * ASCII based protocols (eg. HTTP). The specifications (RFC2616, 2398)

     * are a little ambiguous in this matter. For instance, RFC2398 [part 2.1]

     * says that the HTTP request URI should be escaped using a defined

     * mechanism, but there is no way to specify in the escaped string what

     * the original character set is. It is not correct to assume that

     * UTF-8 is always used (as in URLs in HTML 4.0).  For this reason,

     * until the specifications are updated to deal with this issue more

     * comprehensively, and more importantly, HTTP servers are known to

     * support these mechanisms, we will maintain the current behavior

     * where it is possible to send non-ASCII characters in their original

     * unescaped form.

     */

    private static boolean isASCIISuperset(String encoding) throws Exception {

        String chkS = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ" +

                "abcdefghijklmnopqrstuvwxyz-_.!~*'();/?:@&=+$,";

        // Expected byte sequence for string above

        byte[] chkB = {48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 65, 66, 67, 68, 69, 70, 71, 72,

            73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 97, 98, 99,

            100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114,

            115, 116, 117, 118, 119, 120, 121, 122, 45, 95, 46, 33, 126, 42, 39, 40, 41, 59,

            47, 63, 58, 64, 38, 61, 43, 36, 44};

        byte[] b = chkS.getBytes(encoding);

        return java.util.Arrays.equals(b, chkB);

    }

    private class DefaultParser implements FtpDirParser {

        /**

         * Possible patterns:

         *

         *  drwxr-xr-x  1 user01        ftp   512 Jan 29 23:32 prog

         *  drwxr-xr-x  1 user01        ftp   512 Jan 29 1997 prog

         *  drwxr-xr-x  1 1             1     512 Jan 29 23:32 prog

         *  lrwxr-xr-x  1 user01        ftp   512 Jan 29 23:32 prog -> prog2000

         *  drwxr-xr-x  1 username      ftp   512 Jan 29 23:32 prog

         *  -rw-r--r--  1 jcc      staff     105009 Feb  3 15:05 test.1

         *

         *  01-29-97    11:32PM <DIR> prog

         *  04/28/2006  09:12a               3,563 genBuffer.sh

         *

         *  drwxr-xr-x  folder   0       Jan 29 23:32 prog

         *

         *  0 DIR 01-29-97 23:32 PROG

         */

        private DefaultParser() {

        }

        public FtpDirEntry parseLine(String line) {

            String fdate = null;

            String fsize = null;

            String time = null;

            String filename = null;

            String permstring = null;

            String username = null;

            String groupname = null;

            boolean dir = false;

            Calendar now = Calendar.getInstance();

            int year = now.get(Calendar.YEAR);

            Matcher m = null;

            for (int j = 0; j < patterns.length; j++) {

                m = patterns[j].matcher(line);

                if (m.find()) {

                    // 0 - file, 1 - size, 2 - date, 3 - time, 4 - year,

                    // 5 - permissions, 6 - user, 7 - group

                    filename = m.group(patternGroups[j][0]);

                    fsize = m.group(patternGroups[j][1]);

                    fdate = m.group(patternGroups[j][2]);

                    if (patternGroups[j][4] > 0) {

                        fdate += (", " + m.group(patternGroups[j][4]));

                    } else if (patternGroups[j][3] > 0) {

                        fdate += (", " + String.valueOf(year));

                    }

                    if (patternGroups[j][3] > 0) {

                        time = m.group(patternGroups[j][3]);

                    }

                    if (patternGroups[j][5] > 0) {

                        permstring = m.group(patternGroups[j][5]);

                        dir = permstring.startsWith("d");

                    }

                    if (patternGroups[j][6] > 0) {

                        username = m.group(patternGroups[j][6]);

                    }

                    if (patternGroups[j][7] > 0) {

                        groupname = m.group(patternGroups[j][7]);

                    }

                    // Old DOS format

                    if ("<DIR>".equals(fsize)) {

                        dir = true;

                        fsize = null;

                    }

                }

            }

            if (filename != null) {

                Date d;

                try {

                    d = df.parse(fdate);

                } catch (Exception e) {

                    d = null;

                }

                if (d != null && time != null) {

                    int c = time.indexOf(":");

                    now.setTime(d);

                    now.set(Calendar.HOUR, Integer.parseInt(time.substring(0, c)));

                    now.set(Calendar.MINUTE, Integer.parseInt(time.substring(c + 1)));

                    d = now.getTime();

                }

                // see if it's a symbolic link, i.e. the name if followed

                // by a -> and a path

                Matcher m2 = linkp.matcher(filename);

                if (m2.find()) {

                    // Keep only the name then

                    filename = m2.group(1);

                }

                boolean[][] perms = new boolean[3][3];

                for (int i = 0; i < 3; i++) {

                    for (int j = 0; j < 3; j++) {

                        perms[i][j] = (permstring.charAt((i * 3) + j) != '-');

                    }

                }

                FtpDirEntry file = new FtpDirEntry(filename);

                file.setUser(username).setGroup(groupname);

                file.setSize(Long.parseLong(fsize)).setLastModified(d);

                file.setPermissions(perms);

                file.setType(dir ? FtpDirEntry.Type.DIR : (line.charAt(0) == 'l' ? FtpDirEntry.Type.LINK : FtpDirEntry.Type.FILE));

                return file;

            }

            return null;

        }

    }

    private class MLSxParser implements FtpDirParser {

        private SimpleDateFormat df = new SimpleDateFormat("yyyyMMddhhmmss");

        public FtpDirEntry parseLine(String line) {

            String name = null;

            int i = line.lastIndexOf(";");

            if (i > 0) {

                name = line.substring(i + 1).trim();

                line = line.substring(0, i);

            } else {

                name = line.trim();

                line = "";

            }

            FtpDirEntry file = new FtpDirEntry(name);

            while (!line.isEmpty()) {

                String s;

                i = line.indexOf(";");

                if (i > 0) {

                    s = line.substring(0, i);

                    line = line.substring(i + 1);

                } else {

                    s = line;

                    line = "";

                }

                i = s.indexOf("=");

                if (i > 0) {

                    String fact = s.substring(0, i);

                    String value = s.substring(i + 1);

                    file.addFact(fact, value);

                }

            }

            String s = file.getFact("Size");

            if (s != null) {

                file.setSize(Long.parseLong(s));

            }

            s = file.getFact("Modify");

            if (s != null) {

                Date d = null;

                try {

                    d = df.parse(s);

                } catch (ParseException ex) {

                }

                if (d != null) {

                    file.setLastModified(d);

                }

            }

            s = file.getFact("Create");

            if (s != null) {

                Date d = null;

                try {

                    d = df.parse(s);

                } catch (ParseException ex) {

                }

                if (d != null) {

                    file.setCreated(d);

                }

            }

            s = file.getFact("Type");

            if (s != null) {

                if (s.equalsIgnoreCase("file")) {

                    file.setType(FtpDirEntry.Type.FILE);

                }

                if (s.equalsIgnoreCase("dir")) {

                    file.setType(FtpDirEntry.Type.DIR);

                }

                if (s.equalsIgnoreCase("cdir")) {

                    file.setType(FtpDirEntry.Type.CDIR);

                }

                if (s.equalsIgnoreCase("pdir")) {

                    file.setType(FtpDirEntry.Type.PDIR);

                }

            }

            return file;

        }

    };

    private FtpDirParser parser = new DefaultParser();

    private FtpDirParser mlsxParser = new MLSxParser();

    private static Pattern transPat = null;

    private void getTransferSize() {

        lastTransSize = -1;

        /**

         * If it's a start of data transfer response, let's try to extract

         * the size from the response string. Usually it looks like that:

         *

         * 150 Opening BINARY mode data connection for foo (6701 bytes).

         */

        String response = getLastResponseString();

        if (transPat == null) {

            transPat = Pattern.compile("150 Opening .*\\((\\d+) bytes\\).");

        }

        Matcher m = transPat.matcher(response);

        if (m.find()) {

            String s = m.group(1);

            lastTransSize = Long.parseLong(s);

        }

    }

    /**

     * extract the created file name from the response string:

     * 226 Transfer complete (unique file name:toto.txt.1).

     * Usually happens when a STOU (store unique) command had been issued.

     */

    private void getTransferName() {

        lastFileName = null;

        String response = getLastResponseString();

        int i = response.indexOf("unique file name:");

        int e = response.lastIndexOf(')');

        if (i >= 0) {

            i += 17; // Length of "unique file name:"

            lastFileName = response.substring(i, e);

        }

    }

    /**

     * Pulls the response from the server and returns the code as a

     * number. Returns -1 on failure.

     */

    private int readServerResponse() throws IOException {

        StringBuffer replyBuf = new StringBuffer(32);

        int c;

        int continuingCode = -1;

        int code;

        String response;

        serverResponse.setSize(0);

        while (true) {

            while ((c = in.read()) != -1) {

                if (c == '\r') {

                    if ((c = in.read()) != '\n') {

                        replyBuf.append('\r');

                    }

                }

                replyBuf.append((char) c);

                if (c == '\n') {

                    break;

                }

            }

            response = replyBuf.toString();

            replyBuf.setLength(0);

            if (logger.isLoggable(PlatformLogger.FINEST)) {

                logger.finest("Server [" + serverAddr + "] --> " + response);

            }

            if (response.length() == 0) {

                code = -1;

            } else {

                try {

                    code = Integer.parseInt(response.substring(0, 3));

                } catch (NumberFormatException e) {

                    code = -1;

                } catch (StringIndexOutOfBoundsException e) {

                    /* this line doesn't contain a response code, so

                    we just completely ignore it */

                    continue;

                }

            }

            serverResponse.addElement(response);

            if (continuingCode != -1) {

                /* we've seen a ###- sequence */

                if (code != continuingCode ||

                        (response.length() >= 4 && response.charAt(3) == '-')) {

                    continue;

                } else {

                    /* seen the end of code sequence */

                    continuingCode = -1;

                    break;

                }

            } else if (response.length() >= 4 && response.charAt(3) == '-') {

                continuingCode = code;

                continue;

            } else {

                break;

            }

        }

        return code;

    }

    /** Sends command <i>cmd</i> to the server. */

    private void sendServer(String cmd) {

        out.print(cmd);

        if (logger.isLoggable(PlatformLogger.FINEST)) {

            logger.finest("Server [" + serverAddr + "] <-- " + cmd);

        }

    }

    /** converts the server response into a string. */

    private String getResponseString() {

        return serverResponse.elementAt(0);

    }

    /** Returns all server response strings. */

    private Vector<String> getResponseStrings() {

        return serverResponse;

    }

    /**

     * Read the reply from the FTP server.

     *

     * @return <code>true</code> if the command was successful

     * @throws IOException if an error occured

     */

    private boolean readReply() throws IOException {

        lastReplyCode = FtpReplyCode.find(readServerResponse());

        if (lastReplyCode.isPositivePreliminary()) {

            replyPending = true;

            return true;

        }

        if (lastReplyCode.isPositiveCompletion() || lastReplyCode.isPositiveIntermediate()) {

            if (lastReplyCode == FtpReplyCode.CLOSING_DATA_CONNECTION) {

                getTransferName();

            }

            return true;

        }

        return false;

    }

    /**

     * Sends a command to the FTP server and returns the error code

     * (which can be a "success") sent by the server.

     *

     * @param cmd

     * @return <code>true</code> if the command was successful

     * @throws IOException

     */

    private boolean issueCommand(String cmd) throws IOException {

        if (!isConnected()) {

            throw new IllegalStateException("Not connected");

        }

        if (replyPending) {

            try {

                completePending();

            } catch (sun.net.ftp.FtpProtocolException e) {

                // ignore...

            }

        }

        sendServer(cmd + "\r\n");