/*
 * Copyright (c) 2007-2008 Nokia Corporation and/or its subsidiary(-ies).
 * All rights reserved.
 * This component and the accompanying materials are made available
 * under the terms of the License "Eclipse Public License v1.0"
 * which accompanies this distribution, and is available
 * at the URL "http://www.eclipse.org/legal/epl-v10.html".
 *
 * Initial Contributors:
 * Nokia Corporation - initial contribution.
 *
 * Contributors:
 *
 * Description:  
 *
 */

package com.nokia.helium.core;

import java.util.Arrays;
import java.util.Properties;
import java.util.zip.GZIPOutputStream;
import java.io.BufferedInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;

import javax.mail.BodyPart;
import javax.mail.Message;
import javax.mail.MessagingException;
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 javax.activation.DataHandler;
import javax.mail.util.ByteArrayDataSource;
import javax.mail.internet.AddressException;

import org.apache.log4j.Logger;
import org.apache.commons.io.FileUtils;

/**
 * Send compressed or uncompressed xml data with email.
 */
public class EmailDataSender {

    // Logger
    private static Logger log = Logger.getLogger(EmailDataSender.class);

    // Address email is sent from
    private String from;

    // The target address
    private String[] toAddressList;

    // LDAP config
    private String ldapURL;
    // TODO all reference to nokia internals MUST be removed.
    private String rootdn = "o=Nokia";

    // Configured smtp server address
    private String smtpServerAddress;

    /**
     * Constructor
     * 
     * @param String comma separeted email recepients list
     * @param String smtp server
     * @param String ldap server
     */
    public EmailDataSender(String toStrings, String smtpServer, String ldapAddress) {
        if (toStrings != null) {
            String[] splitList = toStrings.split(",");
            toAddressList = splitList;
        }
        smtpServerAddress = smtpServer;
        ldapURL = ldapAddress;
    }

    /**
     * Constructor
     * 
     * @param String email recepient list in array
     * @param String smtp server
     * @param String ldap server
     */
    public EmailDataSender(String[] toList, String smtpServer, String ldapAddress) {
        toAddressList = toList;
        smtpServerAddress = smtpServer;
        ldapURL = ldapAddress;
    }

    /**
     * Constructor
     * 
     * @param String email recepients list in array
     * @param String smtp server
     * @param String ldap server
     * @param String root domain in ldap server
     */
    public EmailDataSender(String[] toList, String smtpServer, String ldapAddress, String rootdn) {
        toAddressList = toList;
        smtpServerAddress = smtpServer;
        ldapURL = ldapAddress;
        this.rootdn = rootdn;
    }

    /**
     * Set sender address.
     * 
     * @param String mail sender address
     */
    public void setFrom(String from) {
        this.from = from;
    }

    /**
     * Add current user to recipient list.
     * 
     */
    public void addCurrentUserToAddressList() throws EmailSendException {
        // Create an empty array if needed
        if (toAddressList == null) {
            toAddressList = new String[0];
        }
        try {
            String[] tmpToAddressList = Arrays.copyOf(toAddressList, toAddressList.length + 1);
            tmpToAddressList[tmpToAddressList.length - 1] = getUserEmail();
            toAddressList = tmpToAddressList;
        } catch (LDAPException ex) {
            throw new EmailSendException(ex.getMessage(), ex);
        }
    }

    /**
     * Get recipient address list.
     * 
     * @return Recipient address list.
     */
    private InternetAddress[] getToAddressList() {
        int toListLength = 0;
        if (toAddressList != null) {
            toListLength = toAddressList.length;
        }
        InternetAddress[] addressList = new InternetAddress[toListLength];
        try {
            log.debug("getToAddressList:length: " + toListLength);
            for (int i = 0; i < toListLength; i++) {
                log.debug("getToAddressList:address:" + toAddressList[i]);
                addressList[i] = new InternetAddress(toAddressList[i]);
            }
        }
        catch (AddressException aex) {
            log.error("AddressException: " + aex);
        }
        return addressList;
    }

    /**
     * Send xml data without compression
     * 
     * @param String purpose of this email
     * @param String file to send
     * @param String mime type
     * @param String subject of email
     * @param String header of email
     */
    public void sendData(String purpose, File fileToSend, String mimeType,
            String subject, String header) throws EmailSendException {
        sendData(purpose, fileToSend, mimeType, subject, header, false);
    }

    /**
     * Sending the XML data(compressed) through email.
     * 
     * @param String purpose of this email
     * @param String file to send
     * @param String subject of email
     * @param String header of email
     */
    public void compresseAndSendData(String purpose, File fileToSend,
            String subject, String header) throws EmailSendException {
        sendData(purpose, fileToSend, null, subject, header, true);
    }

    /**
     * Send xml data
     * 
     * @param String purpose of this email
     * @param String file to send
     * @param String mime type
     * @param String subject of email
     * @param String header of mail
     * @param boolean compress data if true
     */
    public void sendData(String purpose, File fileToSend, String mimeType,
            String subject, String header, boolean compressData) throws EmailSendException {
        try {
            log.debug("sendData:Send file: " + fileToSend + " and mimetype: " + mimeType);
            if (fileToSend != null && fileToSend.exists()) {
                InternetAddress[] toAddresses = getToAddressList();
                Properties props = new Properties();
                if (smtpServerAddress != null) {
                    log.debug("sendData:smtp address: " + smtpServerAddress);
                    props.setProperty("mail.smtp.host", smtpServerAddress);
                }
                Session mailSession = Session.getDefaultInstance(props, null);
                MimeMessage message = new MimeMessage(mailSession);
                message.setSubject(subject == null ? "" : subject);
                MimeMultipart multipart = new MimeMultipart("related");
                BodyPart messageBodyPart = new MimeBodyPart();
                ByteArrayDataSource dataSrc = null;
                String fileName = fileToSend.getName();
                if (compressData) {
                    log.debug("Sending compressed data");
                    dataSrc = compressFile(fileToSend);
                    dataSrc.setName(fileName + ".gz");
                    messageBodyPart.setFileName(fileName + ".gz");
                }
                else {
                    log.debug("Sending uncompressed data:");
                    dataSrc = new ByteArrayDataSource(new FileInputStream(fileToSend), mimeType);

                    message.setContent(FileUtils.readFileToString(fileToSend), "text/html");
                    multipart = null;
                }
                String headerToSend = null;
                if (header == null) {
                    headerToSend = "";
                }
                messageBodyPart.setHeader("helium-bld-data", headerToSend);
                messageBodyPart.setDataHandler(new DataHandler(dataSrc));

                if (multipart != null) {
                    multipart.addBodyPart(messageBodyPart); // add to the
                    // multipart
                    message.setContent(multipart);
                }
                try {
                    message.setFrom(getFromAddress());
                }
                catch (AddressException e) {
                    throw new EmailSendException("Error retrieving the from address: " + e.getMessage(), e);
                } catch (LDAPException e) {
                    throw new EmailSendException("Error retrieving the from address: " + e.getMessage(), e);
                }
                message.addRecipients(Message.RecipientType.TO, toAddresses);
                log.info("Sending email alert: " + subject);
                Transport.send(message);
            }
        } catch (MessagingException e) {
            String fullErrorMessage = "Failed sending e-mail: " + purpose;
            if (e.getMessage() != null) {
                fullErrorMessage += ": " + e.getMessage();
            }
            throw new EmailSendException(fullErrorMessage, e);
        } catch (IOException e) {
            String fullErrorMessage = "Failed sending e-mail: " + purpose;
            if (e.getMessage() != null) {
                fullErrorMessage += ": " + e.getMessage();
            }
            // We are Ignoring the errors as no need to fail the build.
            throw new EmailSendException(fullErrorMessage, e);
        }
    }

    /**
     * GZipping a string.
     * 
     * @param data the content to be gzipped.
     * @param filename the name for the file.
     * @return a ByteArrayDataSource.
     */
    protected ByteArrayDataSource compressFile(File fileName) throws IOException {
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        GZIPOutputStream gz = new GZIPOutputStream(out);
        BufferedInputStream bufferedInputStream = new BufferedInputStream(new FileInputStream(fileName));
        byte[] dataBuffer = new byte[512];
        while ((bufferedInputStream.read(dataBuffer)) != -1) {
            gz.write(dataBuffer);
        }
        gz.close();
        bufferedInputStream.close();
        ByteArrayDataSource dataSrc = new ByteArrayDataSource(out.toByteArray(), "application/x-gzip");
        return dataSrc;
    }

    /**
     * Get sender address.
     * 
     * @return sender address.
     * @throws AddressException 
     * @throws LDAPException 
     */
    private InternetAddress getFromAddress() throws AddressException, LDAPException {
        if (from != null) {
            return new InternetAddress(from);
        }
        return new InternetAddress(getUserEmail());
    }

    /**
     * Getting user email.
     * 
     * @return the user email address.
     */
    protected String getUserEmail() throws LDAPException {
        if (ldapURL != null) {
            LDAPHelper helper = new LDAPHelper(this.ldapURL, this.rootdn);
            String email = helper.getUserAttributeAsString(LDAPHelper.EMAIL_ATTRIBUTE_NAME);
            if (email == null) {
                throw new LDAPException("Could not find email for current user. (" + System.getProperty("user.name") + ")");
            }
            return email;
        }
        throw new LDAPException("LDAP url is not defined.");
    }
}