/*
 * Copyright (C) 2001, 2002 Red Hat Inc. All Rights Reserved.
 *
 * The contents of this file are subject to the CCM Public
 * License (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.redhat.com/licenses/ccmpl.html
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 */

package com.arsdigita.docmgr.ui;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.math.BigDecimal;

import javax.mail.MessagingException;
import javax.servlet.http.HttpServletRequest;

import com.arsdigita.bebop.ColumnPanel;
import com.arsdigita.bebop.Form;
import com.arsdigita.bebop.FormData;
import com.arsdigita.bebop.FormProcessException;
import com.arsdigita.bebop.Label;
import com.arsdigita.bebop.PageState;
import com.arsdigita.bebop.RequestLocal;
import com.arsdigita.bebop.SimpleContainer;
import com.arsdigita.bebop.event.FormInitListener;
import com.arsdigita.bebop.event.FormProcessListener;
import com.arsdigita.bebop.event.FormSectionEvent;
import com.arsdigita.bebop.form.Submit;
import com.arsdigita.bebop.form.TextArea;
import com.arsdigita.bebop.form.TextField;
import com.arsdigita.bebop.parameters.NotEmptyValidationListener;
import com.arsdigita.docmgr.File;
import com.arsdigita.docmgr.Util;
import com.arsdigita.domain.DataObjectNotFoundException;
import com.arsdigita.kernel.Kernel;
import com.arsdigita.mail.Mail;
import com.arsdigita.util.StringUtils;

/**
 * This component allows the user to send the document to
 * someone by e-mail. The document is enclosed as an attachment
 * and send using the com.arsdigita.mail package services, this
 * package is built ontop of javax.mail.
 *
 * @see com.arsdigita.mail
 *
 * @author <mailto href="StefanDeusch@computer.org">Stefan Deusch</a>
 * @author <mailto href="ddao@arsdigita.com">David Dao</a>
 */

class FileSendColleagueForm extends Form
    implements FormProcessListener,
               FormInitListener,
               DMConstants
{
    private static final char EMAIL_SEPARATOR = ';';
    private static final String EMAIL_LIST = "emailList";
    private static final String EMAIL_SUBJECT = "subject";
    private static final String DESCRIPTION = "description";

    private RequestLocal m_fileData;
    private TextField m_emailList;
    private TextField m_subject;
    private TextArea m_message;

    private FileInfoPropertiesPane m_parent;

    FileSendColleagueForm(FileInfoPropertiesPane parent) {
        super("FileSendColleagueForm", new ColumnPanel(2));
        m_parent = parent;

        // initialize the file
        m_fileData = new RequestLocal() {
                protected Object initialValue(PageState state) {
                    BigDecimal id = (BigDecimal) state.getValue(FILE_ID_PARAM);
                    File file = null;
                    try {
                        file = new File(id);
                    } catch(DataObjectNotFoundException nfe) {
                        // ...
                    }
                    return file;
                }
            };

        add(SEND_FRIEND_FORM_EMAIL_SUBJECT);
        m_subject = new TextField(EMAIL_SUBJECT);
        m_subject.addValidationListener(new NotEmptyValidationListener());
        add(m_subject);

        add(SEND_FRIEND_FORM_EMAIL_LIST);
        m_emailList = new TextField(EMAIL_LIST);
        m_emailList.addValidationListener(new NotEmptyValidationListener());
        add(m_emailList);

        add(SEND_FRIEND_FORM_DESCRIPTION);
        m_message = new TextArea(DESCRIPTION);
        m_message.setRows(10);
        m_message.setCols(40);
        add(m_message);

        SimpleContainer sc = new SimpleContainer();

        sc.add(new Submit(SEND_FRIEND_FORM_SUBMIT));
        CancelButton cancel = new CancelButton(CANCEL);
        sc.add(cancel);

        add(new Label()); // spacer
        add(sc, ColumnPanel.LEFT);

        addInitListener(this);
        addProcessListener(this);
    }

    private File getFile(PageState s) {
        return (File)m_fileData.get(s);
    }

    /**
     * Pre-fill the e-mail subject field with file name.
     */
    public void init(FormSectionEvent e)
        throws FormProcessException {
        PageState state = e.getPageState();

        if ( Kernel.getContext().getParty() == null ) {
            Util.redirectToLoginPage(state);
            return;
        }

        FormData data = e.getFormData();

        data.put(EMAIL_SUBJECT, getFile(state).getName());
    }


    /**
     * No Form validation happens here, the email addresses are parsed
     * and the file is e-mailed as attachment.
     */
    public void process(FormSectionEvent e)
        throws FormProcessException {

        PageState state = e.getPageState();
        FormData data = e.getFormData();
        HttpServletRequest req = state.getRequest();

        String emailRecpts = (String) m_emailList.getValue(state);
        String recipient[] = StringUtils.split(emailRecpts, EMAIL_SEPARATOR);
        String subject = (String) m_subject.getValue(state);

        // message to go with the doc attachment
        String message = (String) m_message.getValue(state);

        // Sender e-mail address
        String from = DMUtils.getUser(state).getPrimaryEmail().toString();

        File file = getFile(state);
        String filename = file.getName();
        String mimeType = file.getContentType();
        byte[] attachment = getBytes(file);

        for (int i=0; i < recipient.length; i++) {
            // TODO validate email of recipient for format
            sendDocument(recipient[i],
                         from,
                         subject,
                         message,
                         filename,
                         mimeType,
                         attachment);
        }

        m_parent.displayPropertiesAndActions(state);
    }

    /**
     * Send the document as attachement to one e-mail recipient
     */

    private static void sendDocument(String recipient,
                                     String sender,
                                     String subject,
                                     String message,
                                     String filename,
                                     String mimeType,
                                     byte[] attchmnt) {

        try {
            Mail mail =  new Mail(recipient, sender, subject);
            mail.setBody(message);
            mail.attach(attchmnt,  mimeType, filename);
            mail.send();
        } catch (MessagingException exc) {
            exc.printStackTrace();
            // log in some buffer, or schedule for re-try later
        }
    }

    /**
     * Get the bytes from the passed in document resource
     */
    private static byte[] getBytes(File file) {
        ByteArrayOutputStream outputStream = null;
        try {
            outputStream = new ByteArrayOutputStream();
            InputStream inputStream = file.getInputStream();
            byte[] buf = new byte[8192];
            int sz = 0;
            while ((sz = inputStream.read(buf, 0, 8192)) != -1) {
                outputStream.write(buf, 0, sz);
            }
        } catch(IOException iox) {
            iox.printStackTrace();
        }
        return outputStream.toByteArray();
    }
}