/*

 * Copyright (c) 1995, 2011, 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.smtp;

import java.io.*;

import java.net.*;

import sun.net.TransferProtocolClient;

import sun.security.action.GetPropertyAction;

/**

 * This class implements the SMTP client.

 * You can send a piece of mail by creating a new SmtpClient, calling

 * the "to" method to add destinations, calling "from" to name the

 * sender, calling startMessage to return a stream to which you write

 * the message (with RFC733 headers) and then you finally close the Smtp

 * Client.

 *

 * @author      James Gosling

 */

public class SmtpClient extends TransferProtocolClient {

    String mailhost;

    SmtpPrintStream message;

    /**

     * issue the QUIT command to the SMTP server and close the connection.

     */

    public void closeServer() throws IOException {

        if (serverIsOpen()) {

            closeMessage();

            issueCommand("QUIT\r\n", 221);

            super.closeServer();

        }

    }

    void issueCommand(String cmd, int expect) throws IOException {

        sendServer(cmd);

        int reply;

        while ((reply = readServerResponse()) != expect)

            if (reply != 220) {

                throw new SmtpProtocolException(getResponseString());

            }

    }

    private void toCanonical(String s) throws IOException {

        if (s.startsWith("<"))

            issueCommand("rcpt to: " + s + "\r\n", 250);

        else

            issueCommand("rcpt to: <" + s + ">\r\n", 250);

    }

    public void to(String s) throws IOException {

        int st = 0;

        int limit = s.length();

        int pos = 0;

        int lastnonsp = 0;

        int parendepth = 0;

        boolean ignore = false;

        while (pos < limit) {

            int c = s.charAt(pos);

            if (parendepth > 0) {

                if (c == '(')

                    parendepth++;

                else if (c == ')')

                    parendepth--;

                if (parendepth == 0)

                    if (lastnonsp > st)

                        ignore = true;

                    else

                        st = pos + 1;

            } else if (c == '(')

                parendepth++;

            else if (c == '<')

                st = lastnonsp = pos + 1;

            else if (c == '>')

                ignore = true;

            else if (c == ',') {

                if (lastnonsp > st)

                    toCanonical(s.substring(st, lastnonsp));

                st = pos + 1;

                ignore = false;

            } else {

                if (c > ' ' && !ignore)

                    lastnonsp = pos + 1;

                else if (st == pos)

                    st++;

            }

            pos++;

        }

        if (lastnonsp > st)

            toCanonical(s.substring(st, lastnonsp));

    }

    public void from(String s) throws IOException {

        if (s.startsWith("<"))

            issueCommand("mail from: " + s + "\r\n", 250);

        else

            issueCommand("mail from: <" + s + ">\r\n", 250);

    }

    /** open a SMTP connection to host <i>host</i>. */

    private void openServer(String host) throws IOException {

        mailhost = host;

        openServer(mailhost, 25);

        issueCommand("helo "+InetAddress.getLocalHost().getHostName()+"\r\n", 250);

    }

    public PrintStream startMessage() throws IOException {

        issueCommand("data\r\n", 354);

        try {

            message = new SmtpPrintStream(serverOutput, this);

        } catch (UnsupportedEncodingException e) {

            throw new InternalError(encoding+" encoding not found", e);

        }

        return message;

    }

    void closeMessage() throws IOException {

        if (message != null)

            message.close();

    }

    /** New SMTP client connected to host <i>host</i>. */

    public SmtpClient (String host) throws IOException {

        super();

        if (host != null) {

            try {

                openServer(host);

                mailhost = host;

                return;

            } catch(Exception e) {

            }

        }

        try {

            String s;

            if (mailhost != null) {

                openServer(mailhost);

                return;

            }

        } catch(Exception e) {

        }

        try {

            mailhost = "localhost";

            openServer(mailhost);

        } catch(Exception e) {

            mailhost = "mailhost";

            openServer(mailhost);

        }

    }

    /** Create an uninitialized SMTP client. */

    public SmtpClient () throws IOException {

        this(null);

    }

    public SmtpClient(int to) throws IOException {

        super();

        setConnectTimeout(to);

        try {

            String s;

            if (mailhost != null) {

                openServer(mailhost);

                return;

            }

        } catch(Exception e) {

        }

        try {

            mailhost = "localhost";

            openServer(mailhost);

        } catch(Exception e) {

            mailhost = "mailhost";

            openServer(mailhost);

        }

    }

    public String getMailHost() {

        return mailhost;

    }

    String getEncoding () {

        return encoding;

    }

}

class SmtpPrintStream extends java.io.PrintStream {

    private SmtpClient target;

    private int lastc = '\n';

    SmtpPrintStream (OutputStream fos, SmtpClient cl) throws UnsupportedEncodingException {

        super(fos, false, cl.getEncoding());

        target = cl;

    }

    public void close() {

        if (target == null)

            return;

        if (lastc != '\n') {

            write('\n');

        }

        try {

            target.issueCommand(".\r\n", 250);

            target.message = null;

            out = null;

            target = null;

        } catch (IOException e) {

        }

    }

    public void write(int b) {

        try {

            // quote a dot at the beginning of a line

            if (lastc == '\n' && b == '.') {

                out.write('.');

            }

            // translate NL to CRLF

            if (b == '\n' && lastc != '\r') {

                out.write('\r');

            }

            out.write(b);

            lastc = b;

        } catch (IOException e) {

        }

    }

    public void write(byte b[], int off, int len) {

        try {

            int lc = lastc;

            while (--len >= 0) {

                int c = b[off++];

                // quote a dot at the beginning of a line

                if (lc == '\n' && c == '.')

                    out.write('.');

                // translate NL to CRLF

                if (c == '\n' && lc != '\r') {

                    out.write('\r');

                }

                out.write(c);

                lc = c;

            }

            lastc = lc;

        } catch (IOException e) {

        }

    }

    public void print(String s) {

        int len = s.length();

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

            write(s.charAt(i));

        }

    }

}