/*

  * Copyright (c) 2003-2011, Simon Brown

  * All rights reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions are met:

  *

  *   - Redistributions of source code must retain the above copyright

  *     notice, this list of conditions and the following disclaimer.

  *

  *   - Redistributions in binary form must reproduce the above copyright

  *     notice, this list of conditions and the following disclaimer in

  *     the documentation and/or other materials provided with the

  *     distribution.

  *

  *   - Neither the name of Pebble nor the names of its contributors may

  *     be used to endorse or promote products derived from this software

  *     without specific prior written permission.

  *

  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE

  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

  * POSSIBILITY OF SUCH DAMAGE.

  */

 package net.sourceforge.pebble.util;

 import net.sourceforge.pebble.domain.Blog;

 import net.sourceforge.pebble.domain.State;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 import net.sourceforge.pebble.web.validation.ValidationContext;

 import net.sourceforge.pebble.PebbleContext;

 import javax.mail.Message;

 import javax.mail.Session;

 import javax.mail.Transport;

 import javax.mail.internet.AddressException;

 import javax.mail.internet.InternetAddress;

 import javax.mail.internet.MimeMessage;

 import javax.mail.internet.MimeUtility;

 import javax.naming.Context;

 import javax.naming.InitialContext;

 import java.util.*;

 import java.util.concurrent.ExecutorService;

 import java.util.concurrent.Executors;

 /**

  * Utilities for e-mail related functions.

  *

  * @author    Simon Brown

  */

 public class MailUtils {

   /** the log used by this class */

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

   private static String ENCODING = "UTF-8";

   /** thread pool used to send e-mail */

   private static ExecutorService pool = Executors.newFixedThreadPool(1);

   /**

    * Get the prefix to be used for blog entry emails

    *

    * @param blog The blog to get the prefix for

    * @return The prefix

    */

   public static String getBlogEntryPrefix(Blog blog) {

     return getPrefix(blog, "notification.prefix.blog.entry", "blogentry.blogentry");

   }

   /**

    * Get the prefix to be used for blog entry emails in the given state

    *

    * @param blog The blog to get the prefix for

    * @param state The state the blog entry is in

    * @return The prefix

    */

   public static String getBlogEntryPrefix(Blog blog, State state) {

     return getPrefix(blog, "notification.prefix.blog.entry", "blogentry.blogentry", state);

   }

   /**

    * Get the prefix to be used for comment emails

    *

    * @param blog The blog to get the prefix for

    * @return The prefix

    */

   public static String getCommentPrefix(Blog blog) {

     return getPrefix(blog, "notification.prefix.comment", "blogentry.comment");

   }

   /**

    * Get the prefix to be used for comment emails

    *

    * @param blog The blog to get the prefix for

    * @param state The state the comment is in

    * @return The prefix

    */

   public static String getCommentPrefix(Blog blog, State state) {

     return getPrefix(blog, "notification.prefix.comment", "blogentry.comment", state);

   }

   /**

    * Get the prefix to be used for trackback emails

    *

    * @param blog The blog to get the prefix for

    * @param state The state the trackback is in

    * @return The prefix

    */

   public static String getTrackbackPrefix(Blog blog, State state) {

     return getPrefix(blog, "notification.prefix.trackback", "blogentry.trackback", state);

   }

   private static String getPrefix(Blog blog, String key, String defaultValue, State state) {

     String value = blog.getProperty(key);

     if (value == null) {

       value = I18n.getMessage(blog, defaultValue);

     }

     return "[" + value + " - " + I18n.getMessage(blog, "admin." + state.getName()) + "]";

   }

   private static String getPrefix(Blog blog, String key, String defaultValue) {

     String value = blog.getProperty(key);

     if (value == null) {

       value = I18n.getMessage(blog, defaultValue);

     }

     return "[" + value + "]";

   }

   /**

    * Sends an e-mail.

    *

    * @param blog    the notifying blog

    * @param to     the e-mail addresses of the recipients in the TO field

    * @param subject       the subject of the e-mail

    * @param message       the body of the e-mail

    */

   public static void sendMail(Session session, Blog blog, String to, String subject, String message) {

     Collection set = new HashSet();

     set.add(to);

     sendMail(session, blog, set, new HashSet(), new HashSet(), subject, message);

   }

   /**

    * Sends an e-mail.

    *

    * @param blog    the notifying blog

    * @param to     the e-mail addresses of the recipients in the TO field

    * @param subject       the subject of the e-mail

    * @param message       the body of the e-mail

    */

   public static void sendMail(Session session, Blog blog, Collection to, String subject, String message) {

     sendMail(session, blog, to, new HashSet(), new HashSet(), subject, message);

   }

   /**

    * Sends an e-mail.

    *

    * @param blog    the notifying blog

    * @param to     the e-mail addresses of the recipients in the TO field

    * @param cc     the e-mail addresses of the recipients in the CC field

    * @param subject       the subject of the e-mail

    * @param message       the body of the e-mail

    */

   public static void sendMail(Session session, Blog blog, Collection to, Collection cc, String subject, String message) {

     sendMail(session, blog, to, cc, new HashSet(), subject, message);

   }

   /**

    * Sends an e-mail.

    *

    * @param blog    the notifying blog

    * @param to     the e-mail addresses of the recipients in the TO field

    * @param cc     the e-mail addresses of the recipients in the CC field

    * @param bcc     the e-mail addresses of the recipients in the BCC field

    * @param subject       the subject of the e-mail

    * @param message       the body of the e-mail

    */

   public static void sendMail(Session session, Blog blog, Collection to, Collection cc, Collection bcc, String subject, String message) {

     Runnable r = new SendMailRunnable(session, blog, to, cc, bcc, subject, message);

     pool.execute(r);

   }

   /**

    * A thread allowing the e-mail to be sent asynchronously, so the requesting

    * thread (and therefore the user) isn't held up.

    */

   static class SendMailRunnable implements Runnable {

     /** the JavaMail session */

     private Session session;

     /** the notifying blog */

     private Blog blog;

     /** the e-mail addresses of the recipients in the TO field */

     private Collection to;

     /** the e-mail addresses of the recipients in the CC field */

     private Collection cc;

     /** the e-mail addresses of the recipients in the BCC field */

     private Collection bcc;

     /** the subject of the e-mail */

     private String subject;

     /** the body of the e-mail */

     private String message;

     /**

      * Creates a new thread to send a new e-mail.

      *

      * @param session   a JavaMail Session instance

      * @param blog    the notifying blog

      * @param to     the e-mail addresses of the recipients in the TO field

      * @param cc     the e-mail addresses of the recipients in the CC field

      * @param bcc     the e-mail addresses of the recipients in the BCC field

      * @param subject       the subject of the e-mail

      * @param message       the body of the e-mail

      */

     public SendMailRunnable(Session session, Blog blog, Collection to, Collection cc, Collection bcc, String subject, String message) {

       this.session = session;

       this.blog = blog;

       this.to = to;

       this.cc = cc;

       this.bcc = bcc;

       this.subject = subject;

       this.message = message;

     }

     /**

      * Performs the processing associated with this thread.

      */

     public void run() {

       try {

         // create a message and try to send it

         Message msg = new MimeMessage(session);

         msg.setFrom(new InternetAddress(blog.getFirstEmailAddress(), MimeUtility.encodeText(blog.getName(), ENCODING, "B")));

         Collection internetAddresses = new HashSet();

         Iterator it = to.iterator();

         while (it.hasNext()) {

           internetAddresses.add(new InternetAddress(it.next().toString()));

         }

         msg.addRecipients(Message.RecipientType.TO, (InternetAddress[])internetAddresses.toArray(new InternetAddress[]{}));

         internetAddresses = new HashSet();

         it = cc.iterator();

         while (it.hasNext()) {

           internetAddresses.add(new InternetAddress(it.next().toString()));

         }

         msg.addRecipients(Message.RecipientType.CC, (InternetAddress[])internetAddresses.toArray(new InternetAddress[]{}));

         internetAddresses = new HashSet();

         it = bcc.iterator();

         while (it.hasNext()) {

           internetAddresses.add(new InternetAddress(it.next().toString()));

         }

         msg.addRecipients(Message.RecipientType.BCC, (InternetAddress[])internetAddresses.toArray(new InternetAddress[]{}));

         msg.setSubject(MimeUtility.encodeText(subject, ENCODING, "B"));

         msg.setSentDate(new Date());

         msg.setContent(message, "text/html; charset=" + ENCODING);

         log.debug("From : " + blog.getName() + " (" + blog.getFirstEmailAddress() + ")");

         log.debug("Subject : " + subject);

         log.debug("Message : " + message);

         Transport.send(msg);

       } catch (Exception e) {

         log.error("Notification e-mail could not be sent", e);

       }

     }

   }

   /**

    * Creates a reference to a JavaMail Session.

    *

    * @return  a Session instance

    * @throws Exception    if something goes wrong creating a session

    */

   public static Session createSession() throws Exception {

     String ref = PebbleContext.getInstance().getConfiguration().getSmtpHost();

     if (ref.startsWith("java:comp/env")) {

       // this is a JNDI based mail session

       Context ctx = new InitialContext();

       return (Session)ctx.lookup(ref);

     } else {

       // this is a simple SMTP hostname based session

       Properties props = new Properties();

       props.put("mail.smtp.host", ref);

       return Session.getDefaultInstance(props, null);

     }

   }

   /**

    * Validates the given comment.

    *

    * @param email   the Comment instance to validate

    * @param context   the context in which to perform validation

    */

   public static void validate(String email, ValidationContext context) {

     if (email != null) {

       try {

         InternetAddress ia = new InternetAddress(email, true);

         ia.validate();

       } catch (AddressException aex) {

         context.addError(aex.getMessage() + ": " + email);

       }

     }

   }

 }