/*
 * #%L
 * Alfresco Repository
 * %%
 * Copyright (C) 2005 - 2016 Alfresco Software Limited
 * %%
 * This file is part of the Alfresco software. 
 * If the software was purchased under a paid Alfresco license, the terms of 
 * the paid license agreement will prevail.  Otherwise, the software is 
 * provided under the following open source license terms:
 * 
 * Alfresco 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 3 of the License, or
 * (at your option) any later version.
 * 
 * Alfresco 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 Alfresco. If not, see <http://www.gnu.org/licenses/>.
 * #L%
 */
package org.alfresco.email.server.handler;

import java.io.IOException;
import java.io.InputStream;
import java.io.Serializable;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;

import javax.mail.MessagingException;

import org.alfresco.error.AlfrescoRuntimeException;
import org.springframework.extensions.surf.util.I18NUtil;
import org.alfresco.model.ContentModel;
import org.alfresco.repo.content.MimetypeMap;
import org.alfresco.service.cmr.email.EmailMessage;
import org.alfresco.service.cmr.email.EmailMessageException;
import org.alfresco.service.cmr.repository.ContentService;
import org.alfresco.service.cmr.repository.ContentWriter;
import org.alfresco.service.cmr.repository.MimetypeService;
import org.alfresco.service.cmr.repository.NodeRef;
import org.alfresco.service.namespace.QName;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * Handler implementation address to folder node.
 * 
 * @author Yan O
 * @since 2.2
 */
public class FolderEmailMessageHandler extends AbstractEmailMessageHandler
{
    private static final String MSG_RECEIVED_BY_SMTP = "email.server.msg.received_by_smtp";
    private static final String MSG_DEFAULT_SUBJECT = "email.server.msg.default_subject";
    private static final String ERR_MAIL_READ_ERROR = "email.server.err.mail_read_error";
    
    private static final Log log = LogFactory.getLog(FolderEmailMessageHandler.class);
    
    /**
     * overwriteDuplicates.
     * if true then overwrite an existing node with the same name.   if false the name is changed to make it unique.
     */ 
    private boolean overwriteDuplicates = false;

    /**
     * {@inheritDoc}
     */
    public void processMessage(NodeRef nodeRef, EmailMessage message)
    {
        if (log.isDebugEnabled())
        {
            log.debug("Message is processing by FolderMailMessageHandler");
        }
        try
        {
            // Check type of the node. It must be a FOLDER
            QName nodeTypeQName = getNodeService().getType(nodeRef);

            if (getDictionaryService().isSubClass(nodeTypeQName, ContentModel.TYPE_FOLDER))
            {
                // Add the content into the system
                addAlfrescoContent(nodeRef, message);
            }
            else
            {
                throw new AlfrescoRuntimeException("\n" +
                        "Message handler " + this.getClass().getName() + " cannot handle type " + nodeTypeQName + ".\n" +
                        "Check the message handler mappings.");
            }
        }
        catch (IOException ex)
        {
            throw new EmailMessageException(ERR_MAIL_READ_ERROR, ex.getMessage());
        }
    }

    /**
     * Add content to Alfresco repository
     * 
     * @param spaceNodeRef          Addressed node
     * @param message            Mail message
     * @throws IOException          Exception can be thrown while saving a content into Alfresco repository.
     */
    public void addAlfrescoContent(NodeRef spaceNodeRef, EmailMessage message) throws IOException
    {
        // Set default values for email fields
        String messageSubject = message.getSubject();
        if (messageSubject == null || messageSubject.length() == 0)
        {
            Date now = new Date();
            messageSubject = I18NUtil.getMessage(MSG_DEFAULT_SUBJECT, new SimpleDateFormat("dd-MM-yyyy-hh-mm-ss").format(now));
        }
        
        String messageFrom = message.getFrom();
        if(messageFrom == null)
        {
            messageFrom = "";
        }

        // Create main content node
        NodeRef contentNodeRef;
        contentNodeRef = addContentNode(getNodeService(), spaceNodeRef, messageSubject, overwriteDuplicates);
        // Add titled aspect
        addTitledAspect(contentNodeRef, messageSubject, messageFrom);
        // Add emailed aspect
        addEmailedAspect(contentNodeRef, message);
        // Write the message content
        if (message.getBody() != null)
        {
            if (message.getBody().getSize() == -1)
            {
                // If message body is empty we write space as a content
                // to make possible rule processing
                // (Rules don't work on empty documents)
                writeSpace(contentNodeRef);
            }
            else
            {
                InputStream contentIs = message.getBody().getContent();
                // The message body is plain text, unless an extension has been provided
                MimetypeService mimetypeService = getMimetypeService();
                String mimetype = mimetypeService.guessMimetype(messageSubject);
                if (mimetype.equals(MimetypeMap.MIMETYPE_BINARY))
                {
                    mimetype = MimetypeMap.MIMETYPE_TEXT_PLAIN;
                }
                // Use the default encoding. It will get overridden if the body is text.
                String encoding = message.getBody().getEncoding();

                writeContent(contentNodeRef, contentIs, mimetype, encoding);
            }
        }

        // Add attachments
        addAttachments(spaceNodeRef, contentNodeRef, message);
    }

    /**
     * This method writes space as a content. We need this space because rules doesn't proceed documents with empty content. We need rule processing for command email messages with
     * empty body.
     * 
     * @param nodeRef Reference to the parent node
     */
    private void writeSpace(NodeRef nodeRef)
    {
        if (log.isDebugEnabled())
        {
            log.debug("Write space string");
        }

        ContentService contentService = getContentService();
        ContentWriter writer = contentService.getWriter(nodeRef, ContentModel.PROP_CONTENT, true);
        writer.setMimetype(MimetypeMap.MIMETYPE_TEXT_PLAIN);
        writer.setEncoding("UTF-8");
        writer.putContent(" ");
    }

    /**
     * Adds titled aspect to the specified node.
     * 
     * @param nodeRef Target node.
     * @param title Title
     */
    private void addTitledAspect(NodeRef nodeRef, String title, String from)
    {
        Map<QName, Serializable> titledProps = new HashMap<QName, Serializable>();
        titledProps.put(ContentModel.PROP_TITLE, title);
        titledProps.put(ContentModel.PROP_DESCRIPTION, I18NUtil.getMessage(MSG_RECEIVED_BY_SMTP, from));
        getNodeService().addAspect(nodeRef, ContentModel.ASPECT_TITLED, titledProps);
        
        if (log.isDebugEnabled())
        {
            log.debug("Titled aspect has been added.");
        }
    }

    /**
     * Set the behaviour to be done on detecting a new message with the same subject.
     * @param overwriteDuplicates boolean
     */
    public void setOverwriteDuplicates(boolean overwriteDuplicates)
    {
        this.overwriteDuplicates = overwriteDuplicates;
    }

    public boolean isOverwriteDuplicates()
    {
        return overwriteDuplicates;
    }
}
