package com.armedia.acm.services.email.service;

/*-
 * #%L
 * ACM Service: Email
 * %%
 * Copyright (C) 2014 - 2018 ArkCase LLC
 * %%
 * This file is part of the ArkCase software. 
 * 
 * If the software was purchased under a paid ArkCase license, the terms of 
 * the paid license agreement will prevail.  Otherwise, the software is 
 * provided under the following open source license terms:
 * 
 * ArkCase 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.
 *  
 * ArkCase 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 ArkCase. If not, see <http://www.gnu.org/licenses/>.
 * #L%
 */

import com.armedia.acm.plugins.ecm.model.AcmFolder;
import com.armedia.acm.plugins.ecm.service.AcmFolderService;
import com.armedia.acm.plugins.ecm.service.EcmFileService;
import com.armedia.acm.web.api.MDCConstants;

import org.apache.commons.lang3.StringUtils;
import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.LogManager;
import org.slf4j.MDC;
import org.springframework.security.core.Authentication;

import javax.mail.BodyPart;
import javax.mail.Message;
import javax.mail.Multipart;
import javax.mail.Part;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.UUID;

/**
 * Created by nebojsha.davidovikj on 1/20/2017.
 */
public class AcmProcessMailServiceImpl implements AcmProcessMailService
{
    private Logger log = LogManager.getLogger(getClass());

    private EcmFileService ecmFileService;
    private AcmFolderService acmFolderService;

    /**
     * iterates through received email and extract attachments and uploads using EcmFileService
     *
     * @param message
     *            received email
     * @param parentObjectId
     *            parent object id which files belong to
     * @param parentObjectType
     *            parent object type which files belong to
     * @param containingFolder
     *            folder under which files will be uploaded, if null than root folder is used
     * @param auth
     *            authentication
     */
    @Override
    public void extractAttachmentsAndUpload(Message message, Long parentObjectId, String parentObjectType, AcmFolder containingFolder,
            Authentication auth)
    {
        // set the Alfresco user id, so as to upload the files.
        MDC.put(MDCConstants.EVENT_MDC_REQUEST_ALFRESCO_USER_ID_KEY, "admin");
        MDC.put(MDCConstants.EVENT_MDC_REQUEST_ID_KEY, UUID.randomUUID().toString());

        String tempDir = System.getProperty("java.io.tmpdir");
        String bodyFileName = parentObjectId + "_" + parentObjectType + "_" + System.currentTimeMillis() + ".eml";// we
                                                                                                                  // must
                                                                                                                  // make
                                                                                                                  // sure
                                                                                                                  // that
                                                                                                                  // file
                                                                                                                  // name
                                                                                                                  // is
                                                                                                                  // unique
                                                                                                                  // that's
                                                                                                                  // why
                                                                                                                  // we
                                                                                                                  // add
                                                                                                                  // timestamp
                                                                                                                  // as
                                                                                                                  // sufix
        File messageFile = new File(tempDir + File.separator + bodyFileName);

        try
        {
            try (OutputStream os = new FileOutputStream(messageFile))
            {
                message.writeTo(os);
            }

            // if no containing folder is provided than root folder is used
            AcmFolder folder = containingFolder != null ? containingFolder
                    : acmFolderService.getRootFolder(parentObjectId, parentObjectType);

            // upload message body
            try (InputStream bodyIS = new FileInputStream(messageFile))
            {
                ecmFileService.upload(bodyFileName, "mail", "Document",
                        bodyIS, "message/rfc822", bodyFileName, auth,
                        folder.getCmisFolderId(), parentObjectType, parentObjectId);
                log.debug("email body uploaded as eml to object an folder [{}, {}, {}, {}]", bodyFileName, folder.getCmisFolderId(),
                        parentObjectId, parentObjectType);
            }
            catch (Exception e)
            {
                // log error and process attachments
                log.error("email body WAS NOT uploaded as eml [{}, {}, {}, {}]", bodyFileName, folder.getCmisFolderId(), parentObjectId,
                        parentObjectType, e);
            }
            finally
            {
                // delete temp file
                messageFile.delete();
            }

            // find attachments and upload
            Multipart multipart = (Multipart) message.getContent();
            for (int i = 0; i < multipart.getCount(); i++)
            {
                BodyPart bodyPart = multipart.getBodyPart(i);
                if (!Part.ATTACHMENT.equalsIgnoreCase(bodyPart.getDisposition()) &&
                        !StringUtils.isNotBlank(bodyPart.getFileName()))
                {
                    continue; // dealing with attachments only
                }

                try (InputStream attachmentIS = bodyPart.getInputStream())
                {
                    String fileName = System.currentTimeMillis() + "_" + bodyPart.getFileName();// we must make sure
                                                                                                // that file name is
                                                                                                // unique that's why we
                                                                                                // add timestamp as
                                                                                                // prefix
                    ecmFileService.upload(fileName, "attachment", "Document",
                            attachmentIS, "message/rfc822", fileName, auth,
                            folder.getCmisFolderId(), parentObjectType, parentObjectId);
                    log.debug("email attachment uploaded [{}, {}, {}, {}]", fileName, folder.getCmisFolderId(), parentObjectId,
                            parentObjectType);
                }
                catch (Exception e)
                {
                    // report error and try to process other attachments
                    log.error("failed to upload attachment [{}, {}, {}, {}]", bodyFileName, folder.getCmisFolderId(), parentObjectId,
                            parentObjectType, e);
                }
            }
        }
        catch (Exception e)
        {
            throw new RuntimeException("Error extracting and uploading attachments of email.", e);
        }
    }

    public void setEcmFileService(EcmFileService ecmFileService)
    {
        this.ecmFileService = ecmFileService;
    }

    public void setAcmFolderService(AcmFolderService acmFolderService)
    {
        this.acmFolderService = acmFolderService;
    }
}