Widerhall/src/main/java/de/srsoftware/widerhall/mail/SmtpClient.java

package de.srsoftware.widerhall.mail;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.mail.*;
import javax.mail.internet.*;
import java.io.UnsupportedEncodingException;
import java.util.Date;
import java.util.List;
import java.util.Properties;

public class SmtpClient {
    private static final Logger LOG = LoggerFactory.getLogger(SmtpClient.class);
    private static final String HOST = "mail.smtp.host";
    private static final String PORT = "mail.smtp.port";
    private static final String AUTH = "mail.smtp.auth";
    private static final String SSL = "mail.smtp.ssl.enable";
    private static final String UTF8 = "UTF-8";
    private final String host,password,username;
    private final int port;
    private boolean forwardUsingListAddress = true;

    private Session session;

    public SmtpClient(String host, int port, String username, String password){
        this.username = username;
        this.password = password;
        this.host = host;
        this.port = port;
    }

    public void bccForward(String from, Message message, List<String> emails) throws MessagingException {
        if (session == null) login();
        MimeMessage forward = new MimeMessage(session);
        forward.setFrom(from);
        forward.setRecipients(Message.RecipientType.BCC,InternetAddress.parse(String.join(", ",emails)));
        forward.setSubject(message.getSubject());

        MimeMultipart multipart = new MimeMultipart();
        MimeBodyPart messageBodyPart = new MimeBodyPart();

        messageBodyPart.setDataHandler(message.getDataHandler());
        multipart.addBodyPart(messageBodyPart);

        forward.setContent(multipart);

        send(forward);
    }


    public SmtpClient login(){
        if (session == null) {
            Properties props = new Properties();
            props.put(HOST, host);
            props.put(PORT, port);
            props.put(AUTH, true);
            props.put(SSL, true);

            session = Session.getInstance(props);
            LOG.debug("Neue Session erzeugt: {}", session);
        }
        return this;
    }

    public void send(String senderAdress, String senderName, String receivers, String subject, String content) throws MessagingException, UnsupportedEncodingException {
        MimeMessage message = new MimeMessage(session);
        message.addHeader("Content-Type","text/plain; charset="+UTF8);
        message.addHeader("format","flowed");
        message.addHeader("Content-Transfer-Encoding","8bit");

        message.setFrom(new InternetAddress(senderAdress,senderName));
        message.setReplyTo(InternetAddress.parse(senderAdress,false));
        message.setSubject(subject,UTF8);
        message.setText(content,UTF8);
        message.setSentDate(new Date());
        message.setRecipients(Message.RecipientType.TO,InternetAddress.parse(receivers,false));
        send(message);
    }

    public void send(Message message) throws MessagingException {
        LOG.debug("Versende Mail…");
        Transport.send(message,username,password);
        LOG.debug("…versendet");

    }

    public String host() {
        return host;
    }

    public int port() {
        return port;
    }

    public String username() {
        return username;
    }

    public String password() {
        return password;
    }

}