/*

 * $Header: /cvsroot/mvnforum/myvietnam/src/net/myvietnam/mvncore/util/MailUtil.java,v 1.65.2.1 2010/04/27 11:27:31 minhnn Exp $

 * $Author: minhnn $

 * $Revision: 1.65.2.1 $

 * $Date: 2010/04/27 11:27:31 $

 *

 * ====================================================================

 *

 * Copyright (C) 2002-2007 by MyVietnam.net

 *

 * All copyright notices regarding MyVietnam and MyVietnam CoreLib

 * MUST remain intact in the scripts and source code.

 *

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

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

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

 * License along with this library; if not, write to the Free Software

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

 *

 * Correspondence and Marketing Questions can be sent to:

 * info at MyVietnam net

 *

 * @author: Minh Nguyen

 * @author: Mai  Nguyen

 */

package net.myvietnam.mvncore.util;



import java.io.IOException;

import java.io.UnsupportedEncodingException;

import java.net.InetAddress;

import java.net.UnknownHostException;

import java.util.*;



import javax.mail.*;

import javax.mail.Flags.Flag;

import javax.mail.internet.*;

import javax.naming.InitialContext;

import javax.naming.NamingException;



import net.myvietnam.mvncore.MVNCoreConfig;

import net.myvietnam.mvncore.MVNCoreConfig.MailConfig;

import net.myvietnam.mvncore.exception.BadInputException;

import net.myvietnam.mvncore.filter.DisableHtmlTagFilter;



import org.apache.commons.logging.Log;

import org.apache.commons.logging.LogFactory;

import org.masukomi.aspirin.core.MailQue;



public final class MailUtil {



    public static final int MAX_MESSAGES_PER_TRANSPORT = 100;



    private static final Log log = LogFactory.getLog(MailUtil.class);



    private MailUtil() {// prevent instantiation

    }



    //private static MailOptions mailOption = new MailOptions();



    /**

     * Get the user name part of an email. Ex: input: test@yahoo.com => output: test

     * @param email String the email

     * @return String the user name part of an email

     */

    public static String getEmailUsername(String email) {

        if (email == null) return "";

        int atIndex = email.indexOf('@');

        if (atIndex == -1) {

            return "";

        }

        return email.substring(0, atIndex);

    }



    /**

     * Get the domain part of an email. Ex: input: test@yahoo.com => output: yahoo.com

     * @param email String the email

     * @return String the user name part of an email

     */

    public static String getEmailDomain(String email) {

        if (email == null) return "";

        int atIndex = email.indexOf('@');

        if (atIndex == -1) {

            return "";

        }

        return email.substring(atIndex + 1);

    }



    /**

     * Check if an email is good and safe or not.

     * This method should be use for all email input from user

     * @param input String

     * @throws BadInputException if email is not good

     */

    public static void checkGoodEmail(String input) throws BadInputException {

        if (input == null) throw new BadInputException("Sorry, null string is not a good email.");//@todo : localize me

        int atIndex = input.indexOf('@');

        int dotIndex = input.lastIndexOf('.');

        if ((atIndex == -1) || (dotIndex == -1) || (atIndex >= dotIndex)) {

            //@todo : localize me

            throw new BadInputException("Error: '" + DisableHtmlTagFilter.filter(input) + "' is not a valid email value. Please try again.");

        }



        // now check for content of the string

        int length = input.length();

        char c;



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

            c = input.charAt(i);

            if ((c >= 'a') && (c <= 'z')) {

                // lower char

            } else if ((c >= 'A') && (c <= 'Z')) {

                // upper char

            } else if ((c >= '0') && (c <= '9')/* && (i != 0)*/) {

                // as of 31 Jan 2004, i relax the email checking

                // so that the email can start with an numeric char

                // hopefully it does not introduce a security bug

                // because this value will be inserted into sql script



                // numeric char

            } else if ( ( (c=='_') || (c=='-') || (c=='.') || (c=='@') ) && (i != 0) ) {

                // _ char

            } else {

                // not good char, throw an BadInputException

                //@todo : localize me

                throw new BadInputException(input + " is not a valid email. Reason: character '" + c + "' is not accepted in an email.");

            }

        }// for



        // last check

        try {

            new javax.mail.internet.InternetAddress(input);

        } catch (Exception ex) {

            log.error("Error when running checkGoodEmail", ex);

            throw new BadInputException("Assertion: don't want to occur in Util.checkGoodEmail");

        }

    }



    /**

     * NOTE: param to, cc, bcc cannot be all empty. At least one must have a valid value

     * @param from : must be a valid email. However, if this param is null,

     *              then the default mail in config file will be use

     * @param to : can be null

     * @param cc : can be null

     * @param bcc: can be null

     * @param subject

     * @param message

     * @throws MessagingException

     * @throws BadInputException

     */

    public static void sendMail(String from, String to, String cc, String bcc, String subject, String message, boolean sendAsHTML)

        throws MessagingException, BadInputException, UnsupportedEncodingException {



        MailMessageStruct mailItem = new MailMessageStruct();

        mailItem.setFrom(from);

        mailItem.setTo(to);

        mailItem.setCc(cc);

        mailItem.setBcc(bcc);

        mailItem.setSubject(subject);

        mailItem.setMessage(message);

        mailItem.setSendAsHtml(sendAsHTML);



        sendMail(mailItem);

    }



    public static void sendMail(InternetAddress from, String to, String cc, String bcc, String subject, String message, boolean sendAsHTML)

        throws MessagingException, BadInputException, UnsupportedEncodingException {

    

        MailMessageStruct mailItem = new MailMessageStruct();

        mailItem.setFrom(from.getAddress());

        mailItem.setFromDisplayName(from.getPersonal());

        mailItem.setTo(to);

        mailItem.setCc(cc);

        mailItem.setBcc(bcc);

        mailItem.setSubject(subject);

        mailItem.setMessage(message);

        mailItem.setSendAsHtml(sendAsHTML);

    

        sendMail(mailItem);

    }



    public static void sendMail(MailMessageStruct mailItem)

        throws MessagingException, BadInputException, UnsupportedEncodingException {



        ArrayList mailList = new ArrayList(1);

        mailList.add(mailItem);

        try {

            sendMail(mailList);

        } catch (MessagingException mex) {

            log.error("MessagingException has occured.", mex);

            log.debug("MessagingException has occured. Detail info:");

            log.debug("from = " + mailItem.getFrom());

            log.debug("to = " + mailItem.getTo());

            log.debug("cc = " + mailItem.getCc());

            log.debug("bcc = " + mailItem.getBcc());

            log.debug("subject = " + mailItem.getSubject());

            log.debug("message = " + mailItem.getMessage());

            throw mex;// this may look redundant, but it is not :-)

        }

    }



    public static void sendMail(Collection mailStructCollection)

        throws MessagingException, BadInputException, UnsupportedEncodingException {



        Session session = null;

        Transport transport = null;

        int totalEmails = mailStructCollection.size();

        int count = 0;

        int sendFailedExceptionCount = 0;



        String server = "";

        String userName = "";

        String password = "";

        int port = 25;



        MailConfig config = MVNCoreConfig.getSendMailConfig();

        boolean useMailsource = config.useMailSource();

        boolean useEmbededMailServer = config.useEmbededSMTPMailServer();



        String smtp = "smtp";

        if (config.isUseSecureConnection()) {

            smtp = "smtps";

        }

        

        try {

            for (Iterator iter = mailStructCollection.iterator(); iter.hasNext(); ) {

                if ((transport == null) || (session == null)) {

                    if (useEmbededMailServer) {

                        session = Session.getDefaultInstance(new Properties());

                    } else if (useMailsource) {

                        try {

                            InitialContext ic = new InitialContext();

                            // mailSourceName = "java:comp/env/mail/mailSession";

                            String mailSourceName = config.getSourceName();

                            log.debug("MailUtil : use mailsource = " + mailSourceName);

                            if (mailSourceName.startsWith("mail:")) {

                                session = (Session) ic.lookup(mailSourceName);

                            } else {

                                session = (Session) ic.lookup("java:comp/env/" + mailSourceName);

                            }

                            transport = session.getTransport(smtp);

                        } catch (NamingException e) {

                            log.error("Cannot get Mail session", e);

                            throw new MessagingException("Cannot get the mail session from JNDI. Send mail failed.");

                        }

                    } else {// does not use datasourse

                        // TODO the variable props could be cached outside of the loop

                        Properties props = new Properties();



                        server = config.getMailServer();

                        port = config.getPort();

                        userName = config.getUserName();

                        password = config.getPassword();



                        // Local host name used in the SMTP HELO or EHLO command

                        try {

                            if (InetAddress.getLocalHost().getHostName() == null) {

                                props.put("mail." + smtp + ".localhost", server);

                            }

                        } catch (UnknownHostException e) {

                            props.put("mail." + smtp + ".localhost", server);

                        }

                        props.put("mail." + smtp + ".host", server);

                        props.put("mail." + smtp + ".port", String.valueOf(port));

                        if ((userName != null) && (userName.length() > 0)) {

                            props.put("mail." + smtp + ".auth", "true");

                        }

                        props.put("mail.debug", "true");

                        session = Session.getDefaultInstance(props, null);

                        transport = session.getTransport(smtp);

                    }// end of does not use datasource



                    if (useEmbededMailServer == false) {

                        if ((userName != null) && (userName.length() > 0)) {

                            transport.connect(server, userName, password);

                        } else {

                            transport.connect();

                        }

                    }

                }



                MailMessageStruct mailItem = (MailMessageStruct)iter.next();



                String from = mailItem.getFrom();

                String fromDisplayName = mailItem.getFromDisplayName();

                String to = mailItem.getTo();

                String cc = mailItem.getCc();

                String bcc = mailItem.getBcc();

                String subject = mailItem.getSubject();

                String message = mailItem.getMessage();



                if (from == null) {

                    from = MVNCoreConfig.getDefaultMailFrom();

                }



                try {

                    // this will also check for email error

                    checkGoodEmail(from);

                    InternetAddress fromAddress = null;

                    if (fromDisplayName == null) {

                        fromAddress = new InternetAddress(from);

                    } else {

                        fromAddress = new InternetAddress(from, fromDisplayName);

                    }

                    InternetAddress[] toAddress = getInternetAddressEmails(to);

                    InternetAddress[] ccAddress = getInternetAddressEmails(cc);

                    InternetAddress[] bccAddress = getInternetAddressEmails(bcc);

                    if ((toAddress == null) && (ccAddress == null) && (bccAddress == null)) {

                        //@todo : localize me

                        throw new BadInputException("Cannot send mail since all To, Cc, Bcc addresses are empty.");

                    }



                    // create a message

                    MimeMessage msg = new MimeMessage(session);

                    msg.setSentDate(new Date());

                    msg.setFrom(fromAddress);



                    if (toAddress != null) {

                        msg.setRecipients(Message.RecipientType.TO, toAddress);

                    }

                    if (ccAddress != null) {

                        msg.setRecipients(Message.RecipientType.CC, ccAddress);

                    }

                    if (bccAddress != null) {

                        msg.setRecipients(Message.RecipientType.BCC, bccAddress);

                    }

                    

                    if (mailItem.isSendAsHtml() == false) {

                        //This code is use to display unicode in Subject

                        //msg.setSubject(MimeUtility.encodeText(subject, "iso-8859-1", "Q"));

                        //msg.setText(message);

                        //String content = new String(message.getBytes(""), "UTF-8");

                        msg.setSubject(subject, "UTF-8");

                        msg.setText(message, "UTF-8");

                    } else {

                        //Below code is use for unicode

                        MimeBodyPart messageBodyPart = new MimeBodyPart();

                        msg.setSubject(subject, "UTF-8");

                        messageBodyPart.setText(message, "UTF-8");

                        messageBodyPart.setHeader("Content-Type", "text/html;charset=UTF-8");

                        messageBodyPart.setHeader("Content-Transfer-Encoding", "quoted-printable");

                        MimeMultipart multipart = new MimeMultipart("alternative");

                        multipart.addBodyPart(messageBodyPart);

                        msg.setContent(multipart);

                    }

                    msg.saveChanges();



                    if (useEmbededMailServer) {

                        MailQue.queMail(msg);

                    } else {

                        transport.sendMessage(msg, msg.getAllRecipients());

                    }



                    if (useEmbededMailServer == false) {

                        // now check if sent 100 emails, then close connection (transport)

                        if ( ((count+1) % MAX_MESSAGES_PER_TRANSPORT) == 0 ) {

                            try {

                                if (transport != null) transport.close();

                            } catch (MessagingException ex) {}

                            transport = null;

                            session = null;

                        }

                    }



                } catch (SendFailedException ex) {

                    sendFailedExceptionCount++;

                    log.error("SendFailedException has occured.", ex);

                    log.warn("SendFailedException has occured. Detail info:");

                    log.warn("from = " + from);

                    log.warn("to = " + to);

                    log.warn("cc = " + cc);

                    log.warn("bcc = " + bcc);

                    log.warn("subject = " + subject);

                    log.info("message = " + message);

                    if ((totalEmails != 1) && (sendFailedExceptionCount > 10)) {

                        throw ex;// this may look redundant, but it is not :-)

                    }

                } catch (MessagingException mex) {

                    log.error("MessagingException has occured.", mex);

                    log.warn("MessagingException has occured. Detail info:");

                    log.warn("from = " + from);

                    log.warn("to = " + to);

                    log.warn("cc = " + cc);

                    log.warn("bcc = " + bcc);

                    log.warn("subject = " + subject);

                    log.info("message = " + message);

                    throw mex;// this may look redundant, but it is not :-)

                }



                // we increase count when send successfully

                count++;

            }//for

        } finally {

            try {

                if (transport != null) transport.close();

            } catch (MessagingException ex) { }

            

            if (totalEmails != 1) {

                String sendMailMethod = "";

                if (useEmbededMailServer) {

                    sendMailMethod = "Embeded SMTP Server";

                } else if (useMailsource) {

                    sendMailMethod = "Mail Source";

                } else {

                    sendMailMethod = "External SMTP Server";

                }

                log.info("sendMail: totalEmails = " + totalEmails + " sent count = " + count + " using " + sendMailMethod);

            }

        }

    }



    /**

     * This method trim the email variable, so if it contains only spaces,

     * then it will be empty string, then we have 0 token :-)

     * The returned value is never null

     */

    public static String[] getEmails(String email) throws BadInputException {

        if (email == null) email = "";

        email = email.trim();// very important

        email = email.replace(',', ';');// replace all occurrence of ',' to ';'

        StringTokenizer t = new StringTokenizer(email, ";");

        String[] ret = new String[t.countTokens()];

        int index = 0;

        while(t.hasMoreTokens()) {

            String mail = t.nextToken().trim();

            checkGoodEmail(mail);

            ret[index] = mail;

            //log.debug(ret[index]);

            index++;

        }

        return ret;

    }



    public static String[] getEmails(String to, String cc, String bcc) throws BadInputException {

        String[] toMail = getEmails(to);

        String[] ccMail = getEmails(cc);

        String[] bccMail= getEmails(bcc);

        String[] ret = new String[toMail.length + ccMail.length + bccMail.length];

        int index = 0;

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

            ret[index] = toMail[i];

            index++;

        }

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

            ret[index] = ccMail[i];

            index++;

        }

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

            ret[index] = bccMail[i];

            index++;

        }

        return ret;

    }



    /**

     * This method will return null if there is not any email

     *

     * @param email

     * @return

     * @throws BadInputException

     * @throws AddressException

     */

    private static InternetAddress[] getInternetAddressEmails(String email)

        throws BadInputException, AddressException {

        String[] mails = getEmails(email);

        if (mails.length == 0) return null;// must return null, not empty array



        //log.debug("to = " + mails);

        InternetAddress[] address = new InternetAddress[mails.length];

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

            address[i] = new InternetAddress(mails[i]);

            //log.debug("to each element = " + mails[i]);

        }

        return address;

    }



    public static MailMessageStruct[] receiveEmail(String popServer, String popUser, String popPassword) {



        Store store = null;

        Folder folder = null;

        MailMessageStruct[] mailMessageStructsArray = null;

        String provider = "pop3";

        if (MVNCoreConfig.getReceiveMailConfig().isUseSecureConnection()) {

            provider = "pop3s";

        }



        try {

            // -- Get hold of the default session --

            Properties props = new Properties();

            props.put("mail.pop3.port", String.valueOf(MVNCoreConfig.getReceiveMailConfig().getPort()));

            Session session = Session.getDefaultInstance(props, null);

            session.setDebug(true);



            // -- Get hold of a POP3 message store, and connect to it --

            store = session.getStore(provider);

            store.connect(popServer, popUser, popPassword);



            // -- Try to get hold of the default folder --

            folder = store.getDefaultFolder();

            if (folder == null) {

                throw new IOException("No default folder");

            }



            // -- ...and its INBOX --

            folder = folder.getFolder("INBOX");

            if (folder == null) {

                throw new IOException("No POP3 INBOX");

            }



            // -- Open the folder for read write --

            folder.open(Folder.READ_WRITE);



            // -- Get the message wrappers and process them --

            Message[] msgs = folder.getMessages();

            mailMessageStructsArray = new MailMessageStruct [msgs.length];

            for (int msgNum = 0; msgNum < msgs.length; msgNum++) {

                mailMessageStructsArray[msgNum] = createMessageStructFromMessage(msgs[msgNum]);

                msgs[msgNum].setFlag(Flag.DELETED, true);

            }



            return mailMessageStructsArray;

        } catch (Exception ex) {

            log.error("Error when receiving email.", ex);

        } finally {

            if (folder != null) {

                try {

                    folder.close(true);

                } catch (MessagingException e) {

                    log.error("Cannot close POP Folder.", e);

                }

            }

            if (store != null) {

                try {

                    store.close();

                } catch (MessagingException e) {

                    log.error("Cannot close POP Store.", e);

                }

            }

        }

        return new MailMessageStruct[0];

    }



    private static MailMessageStruct createMessageStructFromMessage(Message message)

        throws MessagingException, IOException {



        MailMessageStruct mailMessageStruct = new MailMessageStruct();

        String fromEmailString = null;

        Address[] from = message.getFrom();

        if (from != null) {

            Address fromEmail = from[0];

            fromEmailString = ((InternetAddress)fromEmail).getAddress();

        }

        

        String subject = message.getSubject();



        Part messagePart = message;

        Object content = messagePart.getContent();



        // -- or its first body part if it is a multipart message --

        if (content instanceof Multipart) {

            messagePart = ((Multipart)content).getBodyPart(0);

        }



        // -- Get the content type --

        String contentType = (String)messagePart.getContent();

        

        mailMessageStruct.setFrom(fromEmailString);

        mailMessageStruct.setSubject(subject);

        mailMessageStruct.setMessage(contentType);



        return mailMessageStruct;

    }

}