/*
 * Copyright (c) 1997-2020 Oracle and/or its affiliates. All rights reserved.
 * Copyright 2004 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.naming.factory;

import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.Hashtable;
import java.util.Properties;
import java.util.Enumeration;
import jakarta.mail.Session;
import jakarta.mail.internet.InternetAddress;
import jakarta.mail.internet.MimeMessage;
import jakarta.mail.internet.MimePart;
import jakarta.mail.internet.MimePartDataSource;
import javax.naming.Name;
import javax.naming.Context;
import javax.naming.Reference;
import javax.naming.RefAddr;
import javax.naming.spi.ObjectFactory;

/**
 * Factory class that creates a JNDI named Jakarta Mail MimePartDataSource
 * object which can be used for sending email using SMTP.
 * <p>
 * Can be configured in the DefaultContext or Context scope
 * of your server.xml configuration file.
 * <p>
 * Example:
 * <p>
 * <pre>
 * &lt;Resource name="mail/send" auth="CONTAINER"
 *           type="jakarta.mail.internet.MimePartDataSource"/>
 * &lt;ResourceParams name="mail/send">
 *   &lt;parameter>&lt;name>factory&lt;/name>
 *     &lt;value>org.apache.naming.factory.SendMailFactory&lt;/value>
 *   &lt;/parameter>
 *   &lt;parameter>&lt;name>mail.smtp.host&lt;/name>
 *     &lt;value>your.smtp.host&lt;/value>
 *   &lt;/parameter>
 *   &lt;parameter>&lt;name>mail.smtp.user&lt;/name>
 *     &lt;value>someuser&lt;/value>
 *   &lt;/parameter>
 *   &lt;parameter>&lt;name>mail.from&lt;/name>
 *     &lt;value>someuser@some.host&lt;/value>
 *   &lt;/parameter>
 *   &lt;parameter>&lt;name>mail.smtp.sendpartial&lt;/name>
 *     &lt;value>true&lt;/value>
 *   &lt;/parameter>
 *  &lt;parameter>&lt;name>mail.smtp.dsn.notify&lt;/name>
 *     &lt;value>FAILURE&lt;/value>
 *   &lt;/parameter>
 *   &lt;parameter>&lt;name>mail.smtp.dsn.ret&lt;/name>
 *     &lt;value>FULL&lt;/value>
 *   &lt;/parameter>
 * &lt;/ResourceParams>
 * </pre>
 *
 * @author Glenn Nielsen Rich Catlett
 */

public class SendMailFactory implements ObjectFactory {

    // The class name for the javamail MimeMessageDataSource
    protected static final String DataSourceClassName = "jakarta.mail.internet.MimePartDataSource";

    @Override
    public Object getObjectInstance(Object RefObj, Name Nm, Context Ctx, Hashtable<?, ?> Env) throws Exception {
        final Reference Ref = (Reference) RefObj;

        // Creation of the DataSource is wrapped inside a doPrivileged
        // so that Jakarta Mail can read its default properties without
        // throwing Security Exceptions
        if (Ref.getClassName().equals(DataSourceClassName)) {
            return AccessController.doPrivileged(new PrivilegedAction<MimePartDataSource>() {

                @Override
                public MimePartDataSource run() {
                    // set up the smtp session that will send the message
                    Properties props = new Properties();
                    // enumeration of all refaddr
                    Enumeration<RefAddr> list = Ref.getAll();
                    // current refaddr to be set
                    RefAddr refaddr;
                    // set transport to smtp
                    props.put("mail.transport.protocol", "smtp");

                    while (list.hasMoreElements()) {
                        refaddr = list.nextElement();

                        // set property
                        props.put(refaddr.getType(), refaddr.getContent());
                    }
                    try {
                        MimeMessage message = new MimeMessage(Session.getInstance(props));
                        String from = (String) Ref.get("mail.from").getContent();
                        message.setFrom(new InternetAddress(from));
                        message.setSubject("");
                        MimePartDataSource mds = new MimePartDataSource(message);
                        return mds;
                    } catch (Exception e) {
                        return null;
                    }
                }
            });
        } else { // We can't create an instance of the DataSource
            return null;
        }
    }
}