package org.argeo.connect.mail;
   
   import java.util.Map;
   import java.util.Properties;
   
   import javax.mail.Authenticator;
   import javax.mail.Message;
   import javax.mail.MessagingException;
   import javax.mail.Multipart;
  import javax.mail.PasswordAuthentication;
  import javax.mail.Session;
  import javax.mail.Transport;
  import javax.mail.internet.InternetAddress;
  import javax.mail.internet.MimeBodyPart;
  import javax.mail.internet.MimeMessage;
  import javax.mail.internet.MimeMultipart;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.argeo.connect.ConnectException;
  import org.argeo.eclipse.ui.EclipseUiUtils;
  
  /** Sends a mail via JavaMail, local mail command or Google Mail. */
  public class SendMail implements Runnable {
  	private final static Log log = LogFactory.getLog(SendMail.class);
  
  	// See:
  	// http://java.sun.com/developer/onlineTraining/JavaMail/contents.html#JavaMailUsage
  	// http://java.sun.com/products/javamail/FAQ.html#gmail
  
  	// Configure mail sending via system properties
  	// TODO Use a proper deployment configuration mechanism
  	public final static String ARGEO_SEND_MAILS = "org.argeo.connect.mail.dosend";
  	private final static String ARGEO_SMTP_TLS_DEBUG = "org.argeo.connect.smtp.tls.debug";
  	private final static String DEFAULT_ENCODING = "UTF-8";
  
  	private final static boolean sendingActive = Boolean.parseBoolean(System.getProperty(ARGEO_SEND_MAILS, "true"));
  
  	private String host;
  	private String port;
  	private String from;
  	private String to;
  	private String subject;
  	private String plainText;
  	private String htmlText;
  	private String username;
  	private String password;
  
  	public void run() {
  		// String doSend = System.getProperty(ARGEO_SEND_MAILS);
  
  		if (!sendingActive)
  			traceUnsentMail();
  		else {
  			if ("smtp.gmail.com".equals(host))
  				sendWithGMail();
  			else
  				sendWithJavaSmtp();
  		}
  	}
  
  	protected void sendWithJavaSmtp() {
  
  		// See
  		// http://www.oracle.com/webfolder/technetwork/tutorials/obe/java/javamail/javamail.html
  		String doDebugStr = System.getProperty(ARGEO_SMTP_TLS_DEBUG);
  		boolean debug = "true".equals(doDebugStr);
  
  		boolean auth = true;
  		Properties props = new Properties();
  		props.put("mail.smtp.host", host);
  		props.put("mail.smtp.port", port);
  		// To enable sending email without certificate, using port 25
  		props.put("mail.smtp.starttls.enable", false);
  		// To enable sending email with certificate, using port 587
  		// props.put("mail.smtp.starttls.enable", true);
  
  		// switch (protocol) {
  		// case SMTPS:
  		// props.put("mail.smtp.ssl.enable", true);
  		// break;
  		// case TLS:
  		// props.put("mail.smtp.starttls.enable", true);
  		// break;
  		// }
  
  		Authenticator authenticator = null;
  		if (auth) {
  			props.put("mail.smtp.auth", true);
  			authenticator = new Authenticator() {
  				private PasswordAuthentication pa = new PasswordAuthentication(username, password);
  
  				@Override
  				public PasswordAuthentication getPasswordAuthentication() {
  					return pa;
  				}
  			};
  		}
  		Session session = Session.getInstance(props, authenticator);
 		session.setDebug(debug);
 		MimeMessage message = new MimeMessage(session);
 		try {
 			buildJavaMailMessage(message);
 			Transport.send(message);
 		} catch (MessagingException ex) {
 			throw new ConnectException("Unable to send java tls mail to " + to + " with username: " + username, ex);
 		}
 	}
 
 	protected void sendWithGMail() {
 		try {
 			Properties props = new Properties();
 			props.put("mail.smtps.auth", "true");
 			props.put("mail.smtps.host", host);
 			props.put("mail.smtp.starttls.enable", true);
 			Session session = Session.getDefaultInstance(props, null);
 			MimeMessage message = new MimeMessage(session);
 			buildJavaMailMessage(message);
 			Transport t = session.getTransport("smtps");
 			try {
 				t.connect(host, username, password);
 				t.sendMessage(message, message.getAllRecipients());
 			} finally {
 				t.close();
 			}
 			if (log.isDebugEnabled())
 				log.debug("Sent mail to " + to + " with Google Mail");
 		} catch (Exception e) {
 			throw new ConnectException("Cannot send message.", e);
 		}
 	}
 
 	protected void buildJavaMailMessage(MimeMessage message) throws MessagingException {
 		message.setFrom(new InternetAddress(from));
 		InternetAddress toAddr = new InternetAddress(to);
 		message.setRecipient(Message.RecipientType.TO, toAddr);
 		message.setSubject(subject, DEFAULT_ENCODING);
 		if (EclipseUiUtils.notEmpty((htmlText))) {
 			Multipart multipart = new MimeMultipart("alternative");
 			// Plain text
 			MimeBodyPart textPart = new MimeBodyPart();
 			textPart.setText(htmlText, DEFAULT_ENCODING);
 			// Html formatted
 			MimeBodyPart htmlPart = new MimeBodyPart();
 			htmlPart.setText(htmlText, DEFAULT_ENCODING, "html");
 			// Attach to message
 			multipart.addBodyPart(textPart);
 			multipart.addBodyPart(htmlPart);
 			message.setContent(multipart);
 		} else
 			message.setText(plainText, DEFAULT_ENCODING);
 	}
 
 	/**
 	 * Shortcut to pass all data with only one call. We expect valid and non null
 	 * strings for host, from, to, subject, text, username, password (See
 	 * <code>MailProperty</code>
 	 */
 	public void setMailConfig(Map<String, String> mailConfig) {
 		host = mailConfig.get(MailProperty.host.name());
 		port = mailConfig.get(MailProperty.port.name());
 		from = mailConfig.get(MailProperty.from.name());
 		to = mailConfig.get(MailProperty.to.name());
 		subject = mailConfig.get(MailProperty.subject.name());
 		plainText = mailConfig.get(MailProperty.plainText.name());
 		htmlText = mailConfig.get(MailProperty.htmlText.name());
 		username = mailConfig.get(MailProperty.username.name());
 		password = mailConfig.get(MailProperty.password.name());
 	}
 
 	public void setHost(String host) {
 		this.host = host;
 	}
 
 	public void setFrom(String from) {
 		this.from = from;
 	}
 
 	public void setTo(String to) {
 		this.to = to;
 	}
 
 	public void setSubject(String subject) {
 		this.subject = subject;
 	}
 
 	public void setPlainText(String plainText) {
 		this.plainText = plainText;
 	}
 
 	public void setHtmlText(String htmlText) {
 		this.htmlText = htmlText;
 	}
 
 	public void setUsername(String username) {
 		this.username = username;
 	}
 
 	public void setPassword(String password) {
 		this.password = password;
 	}
 
 	private void traceUnsentMail() {
 		StringBuilder builder = new StringBuilder();
 		builder.append("*** MAIL NOT SENT *** ");
 		builder.append("This message should have been sent but mail sending is disabled.\n");
 		builder.append(logMail(false));
 		log.info(builder.toString());
 	}
 
 	public String logMail(boolean html) {
 		StringBuilder builder = new StringBuilder();
 		if (!html) {
 			builder.append("From: ").append(from);
 			builder.append(" - To: ").append(to);
 			builder.append("- Subject: ").append(subject).append("\n");
 			builder.append("Body: \n");
 		}
 		builder.append(html ? htmlText : plainText);
 		return builder.toString();
 	}
 
 	public static boolean isSendingActive() {
 		return sendingActive;
 	}
 
 }