/*
 * DavMail POP/IMAP/SMTP/CalDav/LDAP Exchange Gateway
 * Copyright (C) 2010  Mickael Guessant
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
package davmail.exchange.dav;

import davmail.BundleMessage;
import davmail.Settings;
import davmail.exception.DavMailAuthenticationException;
import davmail.exception.DavMailException;
import davmail.exception.HttpNotFoundException;
import davmail.exception.HttpPreconditionFailedException;
import davmail.exception.InsufficientStorageException;
import davmail.exception.LoginTimeoutException;
import davmail.exception.WebdavNotAvailableException;
import davmail.exchange.ExchangeSession;
import davmail.exchange.VCalendar;
import davmail.exchange.VObject;
import davmail.exchange.VProperty;
import davmail.exchange.XMLStreamUtil;
import davmail.http.HttpClientAdapter;
import davmail.http.URIUtil;
import davmail.http.request.ExchangePropPatchRequest;
import davmail.ui.tray.DavGatewayTray;
import davmail.util.IOUtil;
import davmail.util.StringUtil;
import org.apache.http.Consts;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpResponseException;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpDelete;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpHead;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.methods.HttpPut;
import org.apache.http.client.protocol.HttpClientContext;
import org.apache.http.client.utils.URIUtils;
import org.apache.http.entity.ByteArrayEntity;
import org.apache.http.entity.ContentType;
import org.apache.http.impl.client.BasicCookieStore;
import org.apache.http.impl.client.BasicResponseHandler;
import org.apache.http.message.BasicNameValuePair;
import org.apache.jackrabbit.webdav.DavException;
import org.apache.jackrabbit.webdav.MultiStatus;
import org.apache.jackrabbit.webdav.MultiStatusResponse;
import org.apache.jackrabbit.webdav.client.methods.HttpCopy;
import org.apache.jackrabbit.webdav.client.methods.HttpMove;
import org.apache.jackrabbit.webdav.client.methods.HttpPropfind;
import org.apache.jackrabbit.webdav.client.methods.HttpProppatch;
import org.apache.jackrabbit.webdav.property.DavProperty;
import org.apache.jackrabbit.webdav.property.DavPropertyNameSet;
import org.apache.jackrabbit.webdav.property.DavPropertySet;
import org.apache.jackrabbit.webdav.property.PropEntry;
import org.w3c.dom.Node;

import javax.mail.MessagingException;
import javax.mail.Session;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
import javax.mail.internet.MimePart;
import javax.mail.util.SharedByteArrayInputStream;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FilterInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.NoRouteToHostException;
import java.net.SocketException;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.net.URLStreamHandler;
import java.net.UnknownHostException;
import java.nio.charset.StandardCharsets;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.*;
import java.util.zip.GZIPInputStream;

/**
 * Webdav Exchange adapter.
 * Compatible with Exchange 2003 and 2007 with webdav available.
 */
@SuppressWarnings("rawtypes")
public class DavExchangeSession extends ExchangeSession {
    protected enum FolderQueryTraversal {
        Shallow, Deep
    }

    protected static final DavPropertyNameSet WELL_KNOWN_FOLDERS = new DavPropertyNameSet();

    static {
        WELL_KNOWN_FOLDERS.add(Field.getPropertyName("inbox"));
        WELL_KNOWN_FOLDERS.add(Field.getPropertyName("deleteditems"));
        WELL_KNOWN_FOLDERS.add(Field.getPropertyName("sentitems"));
        WELL_KNOWN_FOLDERS.add(Field.getPropertyName("sendmsg"));
        WELL_KNOWN_FOLDERS.add(Field.getPropertyName("drafts"));
        WELL_KNOWN_FOLDERS.add(Field.getPropertyName("calendar"));
        WELL_KNOWN_FOLDERS.add(Field.getPropertyName("tasks"));
        WELL_KNOWN_FOLDERS.add(Field.getPropertyName("contacts"));
        WELL_KNOWN_FOLDERS.add(Field.getPropertyName("outbox"));
    }

    static final Map<String, String> vTodoToTaskStatusMap = new HashMap<>();
    static final Map<String, String> taskTovTodoStatusMap = new HashMap<>();

    static {
        //taskTovTodoStatusMap.put("0", null);
        taskTovTodoStatusMap.put("1", "IN-PROCESS");
        taskTovTodoStatusMap.put("2", "COMPLETED");
        taskTovTodoStatusMap.put("3", "NEEDS-ACTION");
        taskTovTodoStatusMap.put("4", "CANCELLED");

        //vTodoToTaskStatusMap.put(null, "0");
        vTodoToTaskStatusMap.put("IN-PROCESS", "1");
        vTodoToTaskStatusMap.put("COMPLETED", "2");
        vTodoToTaskStatusMap.put("NEEDS-ACTION", "3");
        vTodoToTaskStatusMap.put("CANCELLED", "4");
    }

    /**
     * HttpClient 4 adapter to replace httpClient
     */
    private final HttpClientAdapter httpClientAdapter;

    /**
     * Various standard mail boxes Urls
     */
    protected String inboxUrl;
    protected String deleteditemsUrl;
    protected String sentitemsUrl;
    protected String sendmsgUrl;
    protected String draftsUrl;
    protected String calendarUrl;
    protected String tasksUrl;
    protected String contactsUrl;
    protected String outboxUrl;

    protected String inboxName;
    protected String deleteditemsName;
    protected String sentitemsName;
    protected String sendmsgName;
    protected String draftsName;
    protected String calendarName;
    protected String tasksName;
    protected String contactsName;
    protected String outboxName;

    protected static final String USERS = "/users/";

    /**
     * HttpClient4 conversion.
     * TODO: move up to ExchangeSession
     */
    protected void getEmailAndAliasFromOptions() {
        // get user mail URL from html body
        HttpGet optionsMethod = new HttpGet("/owa/?ae=Options&t=About");
        try (
                CloseableHttpResponse response = httpClientAdapter.execute(optionsMethod, cloneContext());
                InputStream inputStream = response.getEntity().getContent();
                BufferedReader optionsPageReader = new BufferedReader(new InputStreamReader(inputStream, StandardCharsets.UTF_8))
        ) {
            String line;

            // find email and alias
            //noinspection StatementWithEmptyBody
            while ((line = optionsPageReader.readLine()) != null
                    && (line.indexOf('[') == -1
                    || line.indexOf('@') == -1
                    || line.indexOf(']') == -1
                    || !line.toLowerCase().contains(MAILBOX_BASE))) {
            }
            if (line != null) {
                int start = line.toLowerCase().lastIndexOf(MAILBOX_BASE) + MAILBOX_BASE.length();
                int end = line.indexOf('<', start);
                alias = line.substring(start, end);
                end = line.lastIndexOf(']');
                start = line.lastIndexOf('[', end) + 1;
                email = line.substring(start, end);
            }
        } catch (IOException e) {
            LOGGER.error("Error parsing options page at " + optionsMethod.getURI());
        }
    }

    /**
     * Create a separate Http context to protect session cookies.
     *
     * @return HttpClientContext instance with cookies
     */
    private HttpClientContext cloneContext() {
        // Create a local context to avoid cookie reset on error
        BasicCookieStore cookieStore = new BasicCookieStore();
        cookieStore.addCookies(httpClientAdapter.getCookies().toArray(new org.apache.http.cookie.Cookie[0]));
        HttpClientContext context = HttpClientContext.create();
        context.setCookieStore(cookieStore);
        return context;
    }

    @Override
    public boolean isExpired() throws NoRouteToHostException, UnknownHostException {
        // experimental: try to reset session timeout
        if ("Exchange2007".equals(serverVersion)) {
            HttpGet getMethod = new HttpGet("/owa/");
            try (CloseableHttpResponse response = httpClientAdapter.execute(getMethod)) {
                LOGGER.debug(response.getStatusLine().getStatusCode() + " at /owa/");
            } catch (IOException e) {
                LOGGER.warn(e.getMessage());
            }
        }

        return super.isExpired();
    }


    /**
     * Convert logical or relative folder path to exchange folder path.
     *
     * @param folderPath folder name
     * @return folder path
     */
    public String getFolderPath(String folderPath) {
        String exchangeFolderPath;
        // IMAP path
        if (folderPath.startsWith(INBOX)) {
            exchangeFolderPath = mailPath + inboxName + folderPath.substring(INBOX.length());
        } else if (folderPath.startsWith(TRASH)) {
            exchangeFolderPath = mailPath + deleteditemsName + folderPath.substring(TRASH.length());
        } else if (folderPath.startsWith(DRAFTS)) {
            exchangeFolderPath = mailPath + draftsName + folderPath.substring(DRAFTS.length());
        } else if (folderPath.startsWith(SENT)) {
            exchangeFolderPath = mailPath + sentitemsName + folderPath.substring(SENT.length());
        } else if (folderPath.startsWith(SENDMSG)) {
            exchangeFolderPath = mailPath + sendmsgName + folderPath.substring(SENDMSG.length());
        } else if (folderPath.startsWith(CONTACTS)) {
            exchangeFolderPath = mailPath + contactsName + folderPath.substring(CONTACTS.length());
        } else if (folderPath.startsWith(CALENDAR)) {
            exchangeFolderPath = mailPath + calendarName + folderPath.substring(CALENDAR.length());
        } else if (folderPath.startsWith(TASKS)) {
            exchangeFolderPath = mailPath + tasksName + folderPath.substring(TASKS.length());
        } else if (folderPath.startsWith("public")) {
            exchangeFolderPath = publicFolderUrl + folderPath.substring("public".length());

            // caldav path
        } else if (folderPath.startsWith(USERS)) {
            // get requested principal
            String principal;
            String localPath;
            int principalIndex = folderPath.indexOf('/', USERS.length());
            if (principalIndex >= 0) {
                principal = folderPath.substring(USERS.length(), principalIndex);
                localPath = folderPath.substring(USERS.length() + principal.length() + 1);
                if (localPath.startsWith(LOWER_CASE_INBOX) || localPath.startsWith(INBOX) || localPath.startsWith(MIXED_CASE_INBOX)) {
                    localPath = inboxName + localPath.substring(LOWER_CASE_INBOX.length());
                } else if (localPath.startsWith(CALENDAR)) {
                    localPath = calendarName + localPath.substring(CALENDAR.length());
                } else if (localPath.startsWith(TASKS)) {
                    localPath = tasksName + localPath.substring(TASKS.length());
                } else if (localPath.startsWith(CONTACTS)) {
                    localPath = contactsName + localPath.substring(CONTACTS.length());
                } else if (localPath.startsWith(ADDRESSBOOK)) {
                    localPath = contactsName + localPath.substring(ADDRESSBOOK.length());
                }
            } else {
                principal = folderPath.substring(USERS.length());
                localPath = "";
            }
            if (principal.isEmpty()) {
                exchangeFolderPath = rootPath;
            } else if (alias.equalsIgnoreCase(principal) || (email != null && email.equalsIgnoreCase(principal))) {
                exchangeFolderPath = mailPath + localPath;
            } else {
                LOGGER.debug("Detected shared path for principal " + principal + ", user principal is " + email);
                exchangeFolderPath = rootPath + principal + '/' + localPath;
            }

            // absolute folder path
        } else if (folderPath.startsWith("/")) {
            exchangeFolderPath = folderPath;
        } else {
            exchangeFolderPath = mailPath + folderPath;
        }
        return exchangeFolderPath;
    }

    /**
     * Test if folderPath is inside user mailbox.
     *
     * @param folderPath absolute folder path
     * @return true if folderPath is a public or shared folder
     */
    @Override
    public boolean isSharedFolder(String folderPath) {
        return !getFolderPath(folderPath).toLowerCase().startsWith(mailPath.toLowerCase());
    }

    /**
     * Test if folderPath is main calendar.
     *
     * @param folderPath absolute folder path
     * @return true if folderPath is a public or shared folder
     */
    @Override
    public boolean isMainCalendar(String folderPath) {
        return getFolderPath(folderPath).equalsIgnoreCase(getFolderPath("calendar"));
    }

    @Override
    protected String getCalendarEmail(String folderPath) throws IOException {
        String calendarPath = getFolderPath(folderPath);
        String[] folderNames = calendarPath.split("/");
        if (folderNames.length > 1) {
            // assume folder email is second path element
            return folderNames[1];
        } else {
            // failover to email
            return email;
        }
    }

    /**
     * Build base path for cmd commands (galfind, gallookup).
     *
     * @return cmd base path
     */
    public String getCmdBasePath() {
        if (("Exchange2003".equals(serverVersion) || PUBLIC_ROOT.equals(publicFolderUrl)) && mailPath != null) {
            // public folder is not available => try to use mailbox path
            // Note: This does not work with freebusy, which requires /public/
            return mailPath;
        } else {
            // use public folder url
            return publicFolderUrl;
        }
    }

    /**
     * LDAP to Exchange Criteria Map
     */
    static final HashMap<String, String> GALFIND_CRITERIA_MAP = new HashMap<>();

    static {
        GALFIND_CRITERIA_MAP.put("imapUid", "AN");
        GALFIND_CRITERIA_MAP.put("smtpemail1", "EM");
        GALFIND_CRITERIA_MAP.put("cn", "DN");
        GALFIND_CRITERIA_MAP.put("givenName", "FN");
        GALFIND_CRITERIA_MAP.put("sn", "LN");
        GALFIND_CRITERIA_MAP.put("title", "TL");
        GALFIND_CRITERIA_MAP.put("o", "CP");
        GALFIND_CRITERIA_MAP.put("l", "OF");
        GALFIND_CRITERIA_MAP.put("department", "DP");
    }

    static final HashSet<String> GALLOOKUP_ATTRIBUTES = new HashSet<>();

    static {
        GALLOOKUP_ATTRIBUTES.add("givenName");
        GALLOOKUP_ATTRIBUTES.add("initials");
        GALLOOKUP_ATTRIBUTES.add("sn");
        GALLOOKUP_ATTRIBUTES.add("street");
        GALLOOKUP_ATTRIBUTES.add("st");
        GALLOOKUP_ATTRIBUTES.add("postalcode");
        GALLOOKUP_ATTRIBUTES.add("co");
        GALLOOKUP_ATTRIBUTES.add("departement");
        GALLOOKUP_ATTRIBUTES.add("mobile");
    }

    /**
     * Exchange to LDAP attribute map
     */
    static final HashMap<String, String> GALFIND_ATTRIBUTE_MAP = new HashMap<>();

    static {
        GALFIND_ATTRIBUTE_MAP.put("uid", "AN");
        GALFIND_ATTRIBUTE_MAP.put("smtpemail1", "EM");
        GALFIND_ATTRIBUTE_MAP.put("cn", "DN");
        GALFIND_ATTRIBUTE_MAP.put("displayName", "DN");
        GALFIND_ATTRIBUTE_MAP.put("telephoneNumber", "PH");
        GALFIND_ATTRIBUTE_MAP.put("l", "OFFICE");
        GALFIND_ATTRIBUTE_MAP.put("o", "CP");
        GALFIND_ATTRIBUTE_MAP.put("title", "TL");

        GALFIND_ATTRIBUTE_MAP.put("givenName", "first");
        GALFIND_ATTRIBUTE_MAP.put("initials", "initials");
        GALFIND_ATTRIBUTE_MAP.put("sn", "last");
        GALFIND_ATTRIBUTE_MAP.put("street", "street");
        GALFIND_ATTRIBUTE_MAP.put("st", "state");
        GALFIND_ATTRIBUTE_MAP.put("postalcode", "zip");
        GALFIND_ATTRIBUTE_MAP.put("co", "country");
        GALFIND_ATTRIBUTE_MAP.put("department", "department");
        GALFIND_ATTRIBUTE_MAP.put("mobile", "mobile");
        GALFIND_ATTRIBUTE_MAP.put("roomnumber", "office");
    }

    boolean disableGalFind;

    protected Map<String, Map<String, String>> galFind(String query) throws IOException {
        Map<String, Map<String, String>> results;
        String path = getCmdBasePath() + "?Cmd=galfind" + query;
        HttpGet httpGet = new HttpGet(path);
        try (CloseableHttpResponse response = httpClientAdapter.execute(httpGet)) {
            results = XMLStreamUtil.getElementContentsAsMap(response.getEntity().getContent(), "item", "AN");
            if (LOGGER.isDebugEnabled()) {
                LOGGER.debug(path + ": " + results.size() + " result(s)");
            }
        } catch (IOException e) {
            LOGGER.debug("GET " + path + " failed: " + e + ' ' + e.getMessage());
            disableGalFind = true;
            throw e;
        }
        return results;
    }


    @Override
    public Map<String, ExchangeSession.Contact> galFind(Condition condition, Set<String> returningAttributes, int sizeLimit) throws IOException {
        Map<String, ExchangeSession.Contact> contacts = new HashMap<>();
        //noinspection StatementWithEmptyBody
        if (disableGalFind) {
            // do nothing
        } else if (condition instanceof MultiCondition) {
            List<Condition> conditions = ((ExchangeSession.MultiCondition) condition).getConditions();
            Operator operator = ((ExchangeSession.MultiCondition) condition).getOperator();
            if (operator == Operator.Or) {
                for (Condition innerCondition : conditions) {
                    contacts.putAll(galFind(innerCondition, returningAttributes, sizeLimit));
                }
            } else if (operator == Operator.And && !conditions.isEmpty()) {
                Map<String, ExchangeSession.Contact> innerContacts = galFind(conditions.get(0), returningAttributes, sizeLimit);
                for (ExchangeSession.Contact contact : innerContacts.values()) {
                    if (condition.isMatch(contact)) {
                        contacts.put(contact.getName().toLowerCase(), contact);
                    }
                }
            }
        } else if (condition instanceof AttributeCondition) {
            String searchAttributeName = ((ExchangeSession.AttributeCondition) condition).getAttributeName();
            String searchAttribute = GALFIND_CRITERIA_MAP.get(searchAttributeName);
            if (searchAttribute != null) {
                String searchValue = ((ExchangeSession.AttributeCondition) condition).getValue();
                StringBuilder query = new StringBuilder();
                if ("EM".equals(searchAttribute)) {
                    // mail search, split
                    int atIndex = searchValue.indexOf('@');
                    // remove suffix
                    if (atIndex >= 0) {
                        searchValue = searchValue.substring(0, atIndex);
                    }
                    // split firstname.lastname
                    int dotIndex = searchValue.indexOf('.');
                    if (dotIndex >= 0) {
                        // assume mail starts with firstname
                        query.append("&FN=").append(URIUtil.encodeWithinQuery(searchValue.substring(0, dotIndex)));
                        query.append("&LN=").append(URIUtil.encodeWithinQuery(searchValue.substring(dotIndex + 1)));
                    } else {
                        query.append("&FN=").append(URIUtil.encodeWithinQuery(searchValue));
                    }
                } else {
                    query.append('&').append(searchAttribute).append('=').append(URIUtil.encodeWithinQuery(searchValue));
                }
                Map<String, Map<String, String>> results = galFind(query.toString());
                for (Map<String, String> result : results.values()) {
                    Contact contact = new Contact();
                    contact.setName(result.get("AN"));
                    contact.put("imapUid", result.get("AN"));
                    buildGalfindContact(contact, result);
                    if (needGalLookup(searchAttributeName, returningAttributes)) {
                        galLookup(contact);
                        // iCal fix to suit both iCal 3 and 4:  move cn to sn, remove cn
                    } else if (returningAttributes.contains("apple-serviceslocator")) {
                        if (contact.get("cn") != null && returningAttributes.contains("sn")) {
                            contact.put("sn", contact.get("cn"));
                            contact.remove("cn");
                        }
                    }
                    if (condition.isMatch(contact)) {
                        contacts.put(contact.getName().toLowerCase(), contact);
                    }
                }
            }

        }
        return contacts;
    }

    protected boolean needGalLookup(String searchAttributeName, Set<String> returningAttributes) {
        // return all attributes => call gallookup
        if (returningAttributes == null || returningAttributes.isEmpty()) {
            return true;
            // iCal search, do not call gallookup
        } else if (returningAttributes.contains("apple-serviceslocator")) {
            return false;
            // Lightning search, no need to gallookup
        } else if ("sn".equals(searchAttributeName)) {
            return returningAttributes.contains("sn");
            // search attribute is gallookup attribute, need to fetch value for isMatch
        } else if (GALLOOKUP_ATTRIBUTES.contains(searchAttributeName)) {
            return true;
        }

        for (String attributeName : GALLOOKUP_ATTRIBUTES) {
            if (returningAttributes.contains(attributeName)) {
                return true;
            }
        }
        return false;
    }

    private boolean disableGalLookup;

    /**
     * Get extended address book information for person with gallookup.
     * Does not work with Exchange 2007
     *
     * @param contact galfind contact
     */
    public void galLookup(Contact contact) {
        if (!disableGalLookup) {
            LOGGER.debug("galLookup(" + contact.get("smtpemail1") + ')');
            HttpGet httpGet = new HttpGet(URIUtil.encodePathQuery(getCmdBasePath() + "?Cmd=gallookup&ADDR=" + contact.get("smtpemail1")));
            try (CloseableHttpResponse response = httpClientAdapter.execute(httpGet)) {
                Map<String, Map<String, String>> results = XMLStreamUtil.getElementContentsAsMap(response.getEntity().getContent(), "person", "alias");
                // add detailed information
                if (!results.isEmpty()) {
                    Map<String, String> personGalLookupDetails = results.get(contact.get("uid").toLowerCase());
                    if (personGalLookupDetails != null) {
                        buildGalfindContact(contact, personGalLookupDetails);
                    }
                }
            } catch (IOException e) {
                LOGGER.warn("Unable to gallookup person: " + contact + ", disable GalLookup");
                disableGalLookup = true;
            }
        }
    }

    protected void buildGalfindContact(Contact contact, Map<String, String> response) {
        for (Map.Entry<String, String> entry : GALFIND_ATTRIBUTE_MAP.entrySet()) {
            String attributeValue = response.get(entry.getValue());
            if (attributeValue != null) {
                contact.put(entry.getKey(), attributeValue);
            }
        }
    }

    @Override
    protected String getFreeBusyData(String attendee, String start, String end, int interval) throws IOException {
        String freebusyUrl = publicFolderUrl + "/?cmd=freebusy" +
                "&start=" + start +
                "&end=" + end +
                "&interval=" + interval +
                "&u=SMTP:" + attendee;
        HttpGet httpGet = new HttpGet(freebusyUrl);
        httpGet.setHeader("Content-Type", "text/xml");
        String fbdata;
        try (CloseableHttpResponse response = httpClientAdapter.execute(httpGet)) {
            fbdata = StringUtil.getLastToken(new BasicResponseHandler().handleResponse(response), "<a:fbdata>", "</a:fbdata>");
        }
        return fbdata;
    }

    public DavExchangeSession(HttpClientAdapter httpClientAdapter, java.net.URI uri, String userName) throws IOException {
        this.httpClientAdapter = httpClientAdapter;
        this.userName = userName;
        buildSessionInfo(uri);
    }


    @Override
    public void buildSessionInfo(java.net.URI uri) throws DavMailException {
        buildMailPath(uri);

        // get base http mailbox http urls
        getWellKnownFolders();
    }

    static final String BASE_HREF = "<base href=\"";

    /**
     * Exchange 2003: get mailPath from welcome page
     *
     * @param uri current uri
     * @return mail path from body
     */
    protected String getMailpathFromWelcomePage(java.net.URI uri) {
        String welcomePageMailPath = null;
        // get user mail URL from html body (multi frame)
        HttpGet method = new HttpGet(uri.toString());

        try (
                CloseableHttpResponse response = httpClientAdapter.execute(method);
                InputStream inputStream = response.getEntity().getContent();
                BufferedReader mainPageReader = new BufferedReader(new InputStreamReader(inputStream, StandardCharsets.UTF_8))
        ) {
            String line;
            //noinspection StatementWithEmptyBody
            while ((line = mainPageReader.readLine()) != null && !line.toLowerCase().contains(BASE_HREF)) {
            }
            if (line != null) {
                // Exchange 2003
                int start = line.toLowerCase().indexOf(BASE_HREF) + BASE_HREF.length();
                int end = line.indexOf('\"', start);
                String mailBoxBaseHref = line.substring(start, end);
                URL baseURL = URI.create(mailBoxBaseHref).toURL();
                welcomePageMailPath = URIUtil.decode(baseURL.getPath());
                LOGGER.debug("Base href found in body, mailPath is " + welcomePageMailPath);
            }
        } catch (IOException e) {
            LOGGER.error("Error parsing main page at " + method.getURI(), e);
        }
        return welcomePageMailPath;
    }

    protected void buildMailPath(java.net.URI uri) throws DavMailAuthenticationException {
        // get mailPath from welcome page on Exchange 2003
        mailPath = getMailpathFromWelcomePage(uri);

        //noinspection VariableNotUsedInsideIf
        if (mailPath != null) {
            // Exchange 2003
            serverVersion = "Exchange2003";
            fixClientHost(uri);
            checkPublicFolder();
            buildEmail(uri.getHost());
        } else {
            // Exchange 2007 : get alias and email from options page
            serverVersion = "Exchange2007";

            // Gallookup is an Exchange 2003 only feature
            disableGalLookup = true;
            fixClientHost(uri);
            getEmailAndAliasFromOptions();

            checkPublicFolder();

            // failover: try to get email through Webdav and Galfind
            if (alias == null || email == null) {
                buildEmail(uri.getHost());
            }

            // build standard mailbox link with email
            mailPath = "/exchange/" + email + '/';
        }

        if (mailPath == null || email == null) {
            throw new DavMailAuthenticationException("EXCEPTION_AUTHENTICATION_FAILED_PASSWORD_EXPIRED");
        }
        LOGGER.debug("Current user email is " + email + ", alias is " + alias + ", mailPath is " + mailPath + " on " + serverVersion);
        rootPath = mailPath.substring(0, mailPath.lastIndexOf('/', mailPath.length() - 2) + 1);
    }

    /**
     * Determine user email through various means.
     *
     * @param hostName Exchange server host name for last failover
     */
    public void buildEmail(String hostName) {
        String mailBoxPath = getMailboxPath();
        // mailPath contains either alias or email
        if (mailBoxPath != null && mailBoxPath.indexOf('@') >= 0) {
            email = mailBoxPath;
            alias = getAliasFromMailboxDisplayName();
            if (alias == null) {
                alias = getAliasFromLogin();
            }
        } else {
            // use mailbox name as alias
            alias = mailBoxPath;
            email = getEmail(alias);
            if (email == null) {
                // failover: try to get email from login name
                alias = getAliasFromLogin();
                email = getEmail(alias);
            }
            // another failover : get alias from mailPath display name
            if (email == null) {
                alias = getAliasFromMailboxDisplayName();
                email = getEmail(alias);
            }
            if (email == null) {
                LOGGER.debug("Unable to get user email with alias " + mailBoxPath
                        + " or " + getAliasFromLogin()
                        + " or " + alias
                );
                // last failover: build email from domain name and mailbox display name
                StringBuilder buffer = new StringBuilder();
                // most reliable alias
                if (mailBoxPath != null) {
                    alias = mailBoxPath;
                } else {
                    alias = getAliasFromLogin();
                }
                if (alias == null) {
                    alias = "unknown";
                }
                buffer.append(alias);
                if (alias.indexOf('@') < 0) {
                    buffer.append('@');
                    if (hostName == null) {
                        hostName = "mail.unknown.com";
                    }
                    int dotIndex = hostName.indexOf('.');
                    if (dotIndex >= 0) {
                        buffer.append(hostName.substring(dotIndex + 1));
                    }
                }
                email = buffer.toString();
            }
        }
    }

    /**
     * Get user alias from mailbox display name over Webdav.
     *
     * @return user alias
     */
    public String getAliasFromMailboxDisplayName() {
        if (mailPath == null) {
            return null;
        }
        String displayName = null;
        try {
            Folder rootFolder = getFolder("");
            if (rootFolder == null) {
                LOGGER.warn(new BundleMessage("EXCEPTION_UNABLE_TO_GET_MAIL_FOLDER", mailPath));
            } else {
                displayName = rootFolder.displayName;
            }
        } catch (IOException e) {
            LOGGER.warn(new BundleMessage("EXCEPTION_UNABLE_TO_GET_MAIL_FOLDER", mailPath));
        }
        return displayName;
    }

    /**
     * Get current Exchange alias name from mailbox name
     *
     * @return user name
     */
    protected String getMailboxPath() {
        if (mailPath == null) {
            return null;
        }
        int index = mailPath.lastIndexOf('/', mailPath.length() - 2);
        if (index >= 0 && mailPath.endsWith("/")) {
            return mailPath.substring(index + 1, mailPath.length() - 1);
        } else {
            LOGGER.warn(new BundleMessage("EXCEPTION_INVALID_MAIL_PATH", mailPath));
            return null;
        }
    }

    /**
     * Get user email from global address list (galfind).
     *
     * @param alias user alias
     * @return user email
     */
    public String getEmail(String alias) {
        String emailResult = null;
        if (alias != null && !disableGalFind) {
            try {
                Map<String, Map<String, String>> results = galFind("&AN=" + URIUtil.encodeWithinQuery(alias));
                Map<String, String> result = results.get(alias.toLowerCase());
                if (result != null) {
                    emailResult = result.get("EM");
                }
            } catch (IOException e) {
                // galfind not available
                disableGalFind = true;
                LOGGER.debug("getEmail(" + alias + ") failed");
            }
        }
        return emailResult;
    }

    protected String getURIPropertyIfExists(DavPropertySet properties, String alias) throws IOException {
        DavProperty property = properties.get(Field.getPropertyName(alias));
        if (property == null) {
            return null;
        } else {
            return URIUtil.decode((String) property.getValue());
        }
    }

    // return last folder name from url

    protected String getFolderName(String url) {
        if (url != null) {
            if (url.endsWith("/")) {
                return url.substring(url.lastIndexOf('/', url.length() - 2) + 1, url.length() - 1);
            } else if (url.indexOf('/') > 0) {
                return url.substring(url.lastIndexOf('/') + 1);
            } else {
                return null;
            }
        } else {
            return null;
        }
    }

    protected void fixClientHost(java.net.URI currentUri) {
        // update client host, workaround for Exchange 2003 mailbox with an Exchange 2007 frontend
        if (currentUri != null && currentUri.getHost() != null && currentUri.getScheme() != null) {
            httpClientAdapter.setUri(currentUri);
        }
    }

    protected void checkPublicFolder() {
        // check public folder access
        try {
            publicFolderUrl = URIUtils.resolve(httpClientAdapter.getUri(), PUBLIC_ROOT).toString();
            DavPropertyNameSet davPropertyNameSet = new DavPropertyNameSet();
            davPropertyNameSet.add(Field.getPropertyName("displayname"));

            HttpPropfind httpPropfind = new HttpPropfind(publicFolderUrl, davPropertyNameSet, 0);
            httpClientAdapter.executeDavRequest(httpPropfind);
            // update public folder URI
            publicFolderUrl = httpPropfind.getURI().toString();

        } catch (IOException e) {
            LOGGER.warn("Public folders not available: " + (e.getMessage() == null ? e : e.getMessage()));
            // default public folder path
            publicFolderUrl = PUBLIC_ROOT;
        }
    }


    protected void getWellKnownFolders() throws DavMailException {
        // Retrieve well known URLs
        try {
            HttpPropfind httpPropfind = new HttpPropfind(mailPath, WELL_KNOWN_FOLDERS, 0);
            MultiStatus multiStatus;
            try (CloseableHttpResponse response = httpClientAdapter.execute(httpPropfind)) {
                multiStatus = httpPropfind.getResponseBodyAsMultiStatus(response);
            }
            MultiStatusResponse[] responses = multiStatus.getResponses();
            if (responses.length == 0) {
                throw new WebdavNotAvailableException("EXCEPTION_UNABLE_TO_GET_MAIL_FOLDER", mailPath);
            }
            DavPropertySet properties = responses[0].getProperties(org.apache.http.HttpStatus.SC_OK);
            inboxUrl = getURIPropertyIfExists(properties, "inbox");
            inboxName = getFolderName(inboxUrl);
            deleteditemsUrl = getURIPropertyIfExists(properties, "deleteditems");
            deleteditemsName = getFolderName(deleteditemsUrl);
            sentitemsUrl = getURIPropertyIfExists(properties, "sentitems");
            sentitemsName = getFolderName(sentitemsUrl);
            sendmsgUrl = getURIPropertyIfExists(properties, "sendmsg");
            sendmsgName = getFolderName(sendmsgUrl);
            draftsUrl = getURIPropertyIfExists(properties, "drafts");
            draftsName = getFolderName(draftsUrl);
            calendarUrl = getURIPropertyIfExists(properties, "calendar");
            calendarName = getFolderName(calendarUrl);
            tasksUrl = getURIPropertyIfExists(properties, "tasks");
            tasksName = getFolderName(tasksUrl);
            contactsUrl = getURIPropertyIfExists(properties, "contacts");
            contactsName = getFolderName(contactsUrl);
            outboxUrl = getURIPropertyIfExists(properties, "outbox");
            outboxName = getFolderName(outboxUrl);
            // junk folder not available over webdav

            LOGGER.debug("Inbox URL: " + inboxUrl +
                    " Trash URL: " + deleteditemsUrl +
                    " Sent URL: " + sentitemsUrl +
                    " Send URL: " + sendmsgUrl +
                    " Drafts URL: " + draftsUrl +
                    " Calendar URL: " + calendarUrl +
                    " Tasks URL: " + tasksUrl +
                    " Contacts URL: " + contactsUrl +
                    " Outbox URL: " + outboxUrl +
                    " Public folder URL: " + publicFolderUrl
            );
        } catch (IOException | DavException e) {
            LOGGER.error(e.getMessage());
            throw new WebdavNotAvailableException("EXCEPTION_UNABLE_TO_GET_MAIL_FOLDER", mailPath);
        }
    }

    protected static class MultiCondition extends ExchangeSession.MultiCondition {
        protected MultiCondition(Operator operator, Condition... condition) {
            super(operator, condition);
        }

        public void appendTo(StringBuilder buffer) {
            boolean first = true;

            for (Condition condition : conditions) {
                if (condition != null && !condition.isEmpty()) {
                    if (first) {
                        buffer.append('(');
                        first = false;
                    } else {
                        buffer.append(' ').append(operator).append(' ');
                    }
                    condition.appendTo(buffer);
                }
            }
            // at least one non empty condition
            if (!first) {
                buffer.append(')');
            }
        }
    }

    protected static class NotCondition extends ExchangeSession.NotCondition {
        protected NotCondition(Condition condition) {
            super(condition);
        }

        public void appendTo(StringBuilder buffer) {
            buffer.append("(Not ");
            condition.appendTo(buffer);
            buffer.append(')');
        }
    }

    static final Map<Operator, String> OPERATOR_MAP = new HashMap<>();

    static {
        OPERATOR_MAP.put(Operator.IsEqualTo, " = ");
        OPERATOR_MAP.put(Operator.IsGreaterThanOrEqualTo, " >= ");
        OPERATOR_MAP.put(Operator.IsGreaterThan, " > ");
        OPERATOR_MAP.put(Operator.IsLessThanOrEqualTo, " <= ");
        OPERATOR_MAP.put(Operator.IsLessThan, " < ");
        OPERATOR_MAP.put(Operator.Like, " like ");
        OPERATOR_MAP.put(Operator.IsNull, " is null");
        OPERATOR_MAP.put(Operator.IsFalse, " = false");
        OPERATOR_MAP.put(Operator.IsTrue, " = true");
        OPERATOR_MAP.put(Operator.StartsWith, " = ");
        OPERATOR_MAP.put(Operator.Contains, " = ");
    }

    protected static class AttributeCondition extends ExchangeSession.AttributeCondition {
        protected boolean isIntValue;

        protected AttributeCondition(String attributeName, Operator operator, String value) {
            super(attributeName, operator, value);
        }

        protected AttributeCondition(String attributeName, Operator operator, int value) {
            super(attributeName, operator, String.valueOf(value));
            isIntValue = true;
        }

        public void appendTo(StringBuilder buffer) {
            Field field = Field.get(attributeName);
            buffer.append('"').append(field.getUri()).append('"');
            buffer.append(OPERATOR_MAP.get(operator));
            //noinspection VariableNotUsedInsideIf
            if (field.cast != null) {
                buffer.append("CAST (\"");
            } else if (!isIntValue && !field.isIntValue()) {
                buffer.append('\'');
            }
            if (Operator.Like == operator) {
                buffer.append('%');
            }
            if ("urlcompname".equals(field.alias)) {
                buffer.append(StringUtil.encodeUrlcompname(StringUtil.davSearchEncode(value)));
            } else if (field.isIntValue()) {
                // check value
                try {
                    Integer.parseInt(value);
                    buffer.append(value);
                } catch (NumberFormatException e) {
                    // invalid value, replace with 0
                    buffer.append('0');
                }
            } else {
                buffer.append(StringUtil.davSearchEncode(value));
            }
            if (Operator.Like == operator || Operator.StartsWith == operator) {
                buffer.append('%');
            }
            if (field.cast != null) {
                buffer.append("\" as '").append(field.cast).append("')");
            } else if (!isIntValue && !field.isIntValue()) {
                buffer.append('\'');
            }
        }

        public boolean isMatch(ExchangeSession.Contact contact) {
            String lowerCaseValue = value.toLowerCase();
            String actualValue = contact.get(attributeName);
            Operator actualOperator = operator;
            // patch for iCal or Lightning search without galLookup
            if (actualValue == null && ("givenName".equals(attributeName) || "sn".equals(attributeName))) {
                actualValue = contact.get("cn");
                actualOperator = Operator.Like;
            }
            if (actualValue == null) {
                return false;
            }
            actualValue = actualValue.toLowerCase();
            return (actualOperator == Operator.IsEqualTo && actualValue.equals(lowerCaseValue)) ||
                    (actualOperator == Operator.Like && actualValue.contains(lowerCaseValue)) ||
                    (actualOperator == Operator.StartsWith && actualValue.startsWith(lowerCaseValue));
        }
    }

    protected static class HeaderCondition extends AttributeCondition {

        protected HeaderCondition(String attributeName, Operator operator, String value) {
            super(attributeName, operator, value);
        }

        @Override
        public void appendTo(StringBuilder buffer) {
            buffer.append('"').append(Field.getHeader(attributeName).getUri()).append('"');
            buffer.append(OPERATOR_MAP.get(operator));
            buffer.append('\'');
            if (Operator.Like == operator) {
                buffer.append('%');
            }
            buffer.append(value);
            if (Operator.Like == operator) {
                buffer.append('%');
            }
            buffer.append('\'');
        }
    }

    protected static class MonoCondition extends ExchangeSession.MonoCondition {
        protected MonoCondition(String attributeName, Operator operator) {
            super(attributeName, operator);
        }

        public void appendTo(StringBuilder buffer) {
            buffer.append('"').append(Field.get(attributeName).getUri()).append('"');
            buffer.append(OPERATOR_MAP.get(operator));
        }
    }

    @Override
    public ExchangeSession.MultiCondition and(Condition... condition) {
        return new MultiCondition(Operator.And, condition);
    }

    @Override
    public ExchangeSession.MultiCondition or(Condition... condition) {
        return new MultiCondition(Operator.Or, condition);
    }

    @Override
    public Condition not(Condition condition) {
        if (condition == null) {
            return null;
        } else {
            return new NotCondition(condition);
        }
    }

    @Override
    public Condition isEqualTo(String attributeName, String value) {
        return new AttributeCondition(attributeName, Operator.IsEqualTo, value);
    }

    @Override
    public Condition isEqualTo(String attributeName, int value) {
        return new AttributeCondition(attributeName, Operator.IsEqualTo, value);
    }

    @Override
    public Condition headerIsEqualTo(String headerName, String value) {
        return new HeaderCondition(headerName, Operator.IsEqualTo, value);
    }

    @Override
    public Condition gte(String attributeName, String value) {
        return new AttributeCondition(attributeName, Operator.IsGreaterThanOrEqualTo, value);
    }

    @Override
    public Condition lte(String attributeName, String value) {
        return new AttributeCondition(attributeName, Operator.IsLessThanOrEqualTo, value);
    }

    @Override
    public Condition lt(String attributeName, String value) {
        return new AttributeCondition(attributeName, Operator.IsLessThan, value);
    }

    @Override
    public Condition gt(String attributeName, String value) {
        return new AttributeCondition(attributeName, Operator.IsGreaterThan, value);
    }

    @Override
    public Condition contains(String attributeName, String value) {
        return new AttributeCondition(attributeName, Operator.Like, value);
    }

    @Override
    public Condition startsWith(String attributeName, String value) {
        return new AttributeCondition(attributeName, Operator.StartsWith, value);
    }

    @Override
    public Condition isNull(String attributeName) {
        return new MonoCondition(attributeName, Operator.IsNull);
    }

    @Override
    public Condition exists(String attributeName) {
        return not(new MonoCondition(attributeName, Operator.IsNull));
    }

    @Override
    public Condition isTrue(String attributeName) {
        if ("Exchange2003".equals(this.serverVersion) && "deleted".equals(attributeName)) {
            return isEqualTo(attributeName, "1");
        } else {
            return new MonoCondition(attributeName, Operator.IsTrue);
        }
    }

    @Override
    public Condition isFalse(String attributeName) {
        if ("Exchange2003".equals(this.serverVersion) && "deleted".equals(attributeName)) {
            return or(isEqualTo(attributeName, "0"), isNull(attributeName));
        } else {
            return new MonoCondition(attributeName, Operator.IsFalse);
        }
    }

    /**
     * @inheritDoc
     */
    public class Message extends ExchangeSession.Message {

        @Override
        public String getPermanentId() {
            return permanentUrl;
        }

        @Override
        protected InputStream getMimeHeaders() {
            InputStream result = null;
            try {
                String messageHeaders = getItemProperty(permanentUrl, "messageheaders");
                if (messageHeaders != null) {
                    final String MS_HEADER = "Microsoft Mail Internet Headers Version 2.0";
                    if (messageHeaders.startsWith(MS_HEADER)) {
                        messageHeaders = messageHeaders.substring(MS_HEADER.length());
                        if (!messageHeaders.isEmpty() && messageHeaders.charAt(0) == '\r') {
                            messageHeaders = messageHeaders.substring(1);
                        }
                        if (!messageHeaders.isEmpty() && messageHeaders.charAt(0) == '\n') {
                            messageHeaders = messageHeaders.substring(1);
                        }
                    }
                    // workaround for messages in Sent folder
                    if (!messageHeaders.contains("From:")) {
                        String from = getItemProperty(permanentUrl, "from");
                        messageHeaders = "From: " + from + '\n' + messageHeaders;
                    }
                    result = new ByteArrayInputStream(messageHeaders.getBytes(StandardCharsets.UTF_8));
                }
            } catch (Exception e) {
                LOGGER.warn(e.getMessage());
            }

            return result;
        }
    }


    /**
     * @inheritDoc
     */
    public class Contact extends ExchangeSession.Contact {
        /**
         * Build Contact instance from multistatusResponse info
         *
         * @param multiStatusResponse response
         * @throws IOException      on error
         * @throws DavMailException on error
         */
        public Contact(MultiStatusResponse multiStatusResponse) throws IOException, DavMailException {
            setHref(URIUtil.decode(multiStatusResponse.getHref()));
            DavPropertySet properties = multiStatusResponse.getProperties(HttpStatus.SC_OK);
            permanentUrl = getURLPropertyIfExists(properties, "permanenturl");
            etag = getPropertyIfExists(properties, "etag");
            displayName = getPropertyIfExists(properties, "displayname");
            for (String attributeName : CONTACT_ATTRIBUTES) {
                String value = getPropertyIfExists(properties, attributeName);
                if (value != null) {
                    if ("bday".equals(attributeName) || "anniversary".equals(attributeName)
                            || "lastmodified".equals(attributeName) || "datereceived".equals(attributeName)) {
                        value = convertDateFromExchange(value);
                    } else if ("haspicture".equals(attributeName) || "private".equals(attributeName)) {
                        value = "1".equals(value) ? "true" : "false";
                    }
                    put(attributeName, value);
                }
            }
        }

        public Contact(String folderPath, String itemName, Map<String, String> properties, String etag, String noneMatch) {
            super(folderPath, itemName, properties, etag, noneMatch);
        }

        /**
         * Default constructor for galFind
         */
        public Contact() {
        }

        protected Set<PropertyValue> buildProperties() {
            Set<PropertyValue> propertyValues = new HashSet<>();
            for (Map.Entry<String, String> entry : entrySet()) {
                String key = entry.getKey();
                if (!"photo".equals(key)) {
                    propertyValues.add(Field.createPropertyValue(key, entry.getValue()));
                    if (key.startsWith("email")) {
                        propertyValues.add(Field.createPropertyValue(key + "type", "SMTP"));
                    }
                }
            }

            return propertyValues;
        }

        protected ExchangePropPatchRequest internalCreateOrUpdate(String encodedHref) throws IOException {
            ExchangePropPatchRequest propPatchRequest = new ExchangePropPatchRequest(encodedHref, buildProperties());
            propPatchRequest.setHeader("Translate", "f");
            if (etag != null) {
                propPatchRequest.setHeader("If-Match", etag);
            }
            if (noneMatch != null) {
                propPatchRequest.setHeader("If-None-Match", noneMatch);
            }
            try (CloseableHttpResponse response = httpClientAdapter.execute(propPatchRequest)) {
                LOGGER.debug("internalCreateOrUpdate returned " + response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
            }
            return propPatchRequest;
        }

        /**
         * Create or update contact
         *
         * @return action result
         * @throws IOException on error
         */
        @Override
        public ItemResult createOrUpdate() throws IOException {
            String encodedHref = URIUtil.encodePath(getHref());
            ExchangePropPatchRequest propPatchRequest = internalCreateOrUpdate(encodedHref);
            int status = propPatchRequest.getStatusLine().getStatusCode();
            if (status == HttpStatus.SC_MULTI_STATUS) {
                try {
                    status = propPatchRequest.getResponseStatusCode();
                } catch (HttpResponseException e) {
                    throw new IOException(e.getMessage(), e);
                }
                //noinspection VariableNotUsedInsideIf
                if (status == HttpStatus.SC_CREATED) {
                    LOGGER.debug("Created contact " + encodedHref);
                } else {
                    LOGGER.debug("Updated contact " + encodedHref);
                }
            } else if (status == HttpStatus.SC_NOT_FOUND) {
                LOGGER.debug("Contact not found at " + encodedHref + ", searching permanenturl by urlcompname");
                // failover, search item by urlcompname
                MultiStatusResponse[] responses = searchItems(folderPath, EVENT_REQUEST_PROPERTIES, DavExchangeSession.this.isEqualTo("urlcompname", convertItemNameToEML(itemName)), FolderQueryTraversal.Shallow, 1);
                if (responses.length == 1) {
                    encodedHref = getPropertyIfExists(responses[0].getProperties(HttpStatus.SC_OK), "permanenturl");
                    LOGGER.warn("Contact found, permanenturl is " + encodedHref);
                    propPatchRequest = internalCreateOrUpdate(encodedHref);
                    status = propPatchRequest.getStatusLine().getStatusCode();
                    if (status == HttpStatus.SC_MULTI_STATUS) {
                        try {
                            status = propPatchRequest.getResponseStatusCode();
                        } catch (HttpResponseException e) {
                            throw new IOException(e.getMessage(), e);
                        }
                        LOGGER.debug("Updated contact " + encodedHref);
                    } else {
                        LOGGER.warn("Unable to create or update contact " + status + ' ' + propPatchRequest.getStatusLine());
                    }
                }

            } else {
                LOGGER.warn("Unable to create or update contact " + status + ' ' + propPatchRequest.getStatusLine().getReasonPhrase());
            }
            ItemResult itemResult = new ItemResult();
            // 440 means forbidden on Exchange
            if (status == 440) {
                status = HttpStatus.SC_FORBIDDEN;
            }
            itemResult.status = status;

            if (status == HttpStatus.SC_OK || status == HttpStatus.SC_CREATED) {
                String contactPictureUrl = URIUtil.encodePath(getHref() + "/ContactPicture.jpg");
                String photo = get("photo");
                if (photo != null) {
                    try {
                        final HttpPut httpPut = new HttpPut(contactPictureUrl);
                        // need to update photo
                        byte[] resizedImageBytes = IOUtil.resizeImage(IOUtil.decodeBase64(photo), 90);

                        httpPut.setHeader("Overwrite", "t");
                        // TODO: required ?
                        httpPut.setHeader("Content-Type", "image/jpeg");
                        httpPut.setEntity(new ByteArrayEntity(resizedImageBytes, ContentType.IMAGE_JPEG));

                        try (CloseableHttpResponse response = httpClientAdapter.execute(httpPut)) {
                            status = response.getStatusLine().getStatusCode();
                            if (status != HttpStatus.SC_OK && status != HttpStatus.SC_CREATED) {
                                throw new IOException("Unable to update contact picture: " + status + ' ' + response.getStatusLine().getReasonPhrase());
                            }
                        }
                    } catch (IOException e) {
                        LOGGER.error("Error in contact photo create or update", e);
                        throw e;
                    }

                    Set<PropertyValue> picturePropertyValues = new HashSet<>();
                    picturePropertyValues.add(Field.createPropertyValue("attachmentContactPhoto", "true"));
                    // picturePropertyValues.add(Field.createPropertyValue("renderingPosition", "-1"));
                    picturePropertyValues.add(Field.createPropertyValue("attachExtension", ".jpg"));

                    final ExchangePropPatchRequest attachmentPropPatchRequest = new ExchangePropPatchRequest(contactPictureUrl, picturePropertyValues);
                    try (CloseableHttpResponse response = httpClientAdapter.execute(attachmentPropPatchRequest)) {
                        attachmentPropPatchRequest.handleResponse(response);
                        status = response.getStatusLine().getStatusCode();
                        if (status != HttpStatus.SC_MULTI_STATUS) {
                            LOGGER.error("Error in contact photo create or update: " + response.getStatusLine().getStatusCode());
                            throw new IOException("Unable to update contact picture");
                        }
                    }

                } else {
                    // try to delete picture
                    HttpDelete httpDelete = new HttpDelete(contactPictureUrl);
                    try (CloseableHttpResponse response = httpClientAdapter.execute(httpDelete)) {
                        status = response.getStatusLine().getStatusCode();
                        if (status != HttpStatus.SC_OK && status != HttpStatus.SC_NOT_FOUND) {
                            LOGGER.error("Error in contact photo delete: " + status);
                            throw new IOException("Unable to delete contact picture");
                        }
                    }
                }
                // need to retrieve new etag
                HttpHead headMethod = new HttpHead(URIUtil.encodePath(getHref()));
                try (CloseableHttpResponse response = httpClientAdapter.execute(headMethod)) {
                    if (response.getFirstHeader("ETag") != null) {
                        itemResult.etag = response.getFirstHeader("ETag").getValue();
                    }
                }
            }
            return itemResult;

        }

    }

    /**
     * @inheritDoc
     */
    public class Event extends ExchangeSession.Event {
        protected String instancetype;

        /**
         * Build Event instance from response info.
         *
         * @param multiStatusResponse response
         * @throws IOException on error
         */
        public Event(MultiStatusResponse multiStatusResponse) throws IOException {
            setHref(URIUtil.decode(multiStatusResponse.getHref()));
            DavPropertySet properties = multiStatusResponse.getProperties(HttpStatus.SC_OK);
            permanentUrl = getURLPropertyIfExists(properties, "permanenturl");
            etag = getPropertyIfExists(properties, "etag");
            displayName = getPropertyIfExists(properties, "displayname");
            subject = getPropertyIfExists(properties, "subject");
            instancetype = getPropertyIfExists(properties, "instancetype");
            contentClass = getPropertyIfExists(properties, "contentclass");
        }

        protected String getPermanentUrl() {
            return permanentUrl;
        }

        public Event(String folderPath, String itemName, String contentClass, String itemBody, String etag, String noneMatch) throws IOException {
            super(folderPath, itemName, contentClass, itemBody, etag, noneMatch);
        }

        protected byte[] getICSFromInternetContentProperty() throws IOException, DavException, MessagingException {
            byte[] result = null;
            // PropFind PR_INTERNET_CONTENT
            String propertyValue = getItemProperty(permanentUrl, "internetContent");
            if (propertyValue != null) {
                result = getICS(new ByteArrayInputStream(IOUtil.decodeBase64(propertyValue)));
            }
            return result;
        }

        /**
         * Load ICS content from Exchange server.
         * User Translate: f header to get MIME event content and get ICS attachment from it
         *
         * @return ICS (iCalendar) event
         * @throws IOException on error
         */
        @Override
        public byte[] getEventContent() throws IOException {
            byte[] result = null;
            LOGGER.debug("Get event subject: " + subject + " contentclass: " + contentClass + " href: " + getHref() + " permanentUrl: " + permanentUrl);
            // do not try to load tasks MIME body
            if (!"urn:content-classes:task".equals(contentClass)) {
                // try to get PR_INTERNET_CONTENT
                try {
                    result = getICSFromInternetContentProperty();
                    if (result == null) {
                        HttpGet httpGet = new HttpGet(encodeAndFixUrl(permanentUrl));
                        httpGet.setHeader("Content-Type", "text/xml; charset=utf-8");
                        httpGet.setHeader("Translate", "f");
                        try (CloseableHttpResponse response = httpClientAdapter.execute(httpGet)) {
                            result = getICS(response.getEntity().getContent());
                        }
                    }
                } catch (DavException | IOException | MessagingException e) {
                    LOGGER.warn(e.getMessage());
                }
            }

            // failover: rebuild event from MAPI properties
            if (result == null) {
                try {
                    result = getICSFromItemProperties();
                } catch (IOException e) {
                    deleteBroken();
                    throw e;
                }
            }
            // debug code
            /*if (new String(result).indexOf("VTODO") < 0) {
                LOGGER.debug("Original body: " + new String(result));
                result = getICSFromItemProperties();
                LOGGER.debug("Rebuilt body: " + new String(result));
            }*/

            return result;
        }

        private byte[] getICSFromItemProperties() throws HttpNotFoundException {
            byte[] result;

            // experimental: build VCALENDAR from properties

            try {
                //MultiStatusResponse[] responses = DavGatewayHttpClientFacade.executeMethod(httpClient, propFindMethod);
                Set<String> eventProperties = new HashSet<>();
                eventProperties.add("method");

                eventProperties.add("created");
                eventProperties.add("calendarlastmodified");
                eventProperties.add("dtstamp");
                eventProperties.add("calendaruid");
                eventProperties.add("subject");
                eventProperties.add("dtstart");
                eventProperties.add("dtend");
                eventProperties.add("transparent");
                eventProperties.add("organizer");
                eventProperties.add("to");
                eventProperties.add("description");
                eventProperties.add("rrule");
                eventProperties.add("exdate");
                eventProperties.add("sensitivity");
                eventProperties.add("alldayevent");
                eventProperties.add("busystatus");
                eventProperties.add("reminderset");
                eventProperties.add("reminderdelta");
                // task
                eventProperties.add("importance");
                eventProperties.add("uid");
                eventProperties.add("taskstatus");
                eventProperties.add("percentcomplete");
                eventProperties.add("keywords");
                eventProperties.add("startdate");
                eventProperties.add("duedate");
                eventProperties.add("datecompleted");

                MultiStatusResponse[] responses = searchItems(folderPath, eventProperties, DavExchangeSession.this.isEqualTo("urlcompname", convertItemNameToEML(itemName)), FolderQueryTraversal.Shallow, 1);
                if (responses.length == 0) {
                    throw new HttpNotFoundException(permanentUrl + " not found");
                }
                DavPropertySet davPropertySet = responses[0].getProperties(HttpStatus.SC_OK);
                VCalendar localVCalendar = new VCalendar();
                localVCalendar.setPropertyValue("PRODID", "-//davmail.sf.net/NONSGML DavMail Calendar V1.1//EN");
                localVCalendar.setPropertyValue("VERSION", "2.0");
                localVCalendar.setPropertyValue("METHOD", getPropertyIfExists(davPropertySet, "method"));
                VObject vEvent = new VObject();
                vEvent.setPropertyValue("CREATED", convertDateFromExchange(getPropertyIfExists(davPropertySet, "created")));
                vEvent.setPropertyValue("LAST-MODIFIED", convertDateFromExchange(getPropertyIfExists(davPropertySet, "calendarlastmodified")));
                vEvent.setPropertyValue("DTSTAMP", convertDateFromExchange(getPropertyIfExists(davPropertySet, "dtstamp")));

                String uid = getPropertyIfExists(davPropertySet, "calendaruid");
                if (uid == null) {
                    uid = getPropertyIfExists(davPropertySet, "uid");
                }
                vEvent.setPropertyValue("UID", uid);
                vEvent.setPropertyValue("SUMMARY", getPropertyIfExists(davPropertySet, "subject"));
                vEvent.setPropertyValue("DESCRIPTION", getPropertyIfExists(davPropertySet, "description"));
                vEvent.setPropertyValue("PRIORITY", convertPriorityFromExchange(getPropertyIfExists(davPropertySet, "importance")));
                vEvent.setPropertyValue("CATEGORIES", getPropertyIfExists(davPropertySet, "keywords"));
                String sensitivity = getPropertyIfExists(davPropertySet, "sensitivity");
                if ("2".equals(sensitivity)) {
                    vEvent.setPropertyValue("CLASS", "PRIVATE");
                } else if ("3".equals(sensitivity)) {
                    vEvent.setPropertyValue("CLASS", "CONFIDENTIAL");
                } else if ("0".equals(sensitivity)) {
                    vEvent.setPropertyValue("CLASS", "PUBLIC");
                }

                if (instancetype == null) {
                    vEvent.type = "VTODO";
                    double percentComplete = getDoublePropertyIfExists(davPropertySet, "percentcomplete");
                    if (percentComplete > 0) {
                        vEvent.setPropertyValue("PERCENT-COMPLETE", String.valueOf((int) (percentComplete * 100)));
                    }
                    vEvent.setPropertyValue("STATUS", taskTovTodoStatusMap.get(getPropertyIfExists(davPropertySet, "taskstatus")));
                    vEvent.setPropertyValue("DUE;VALUE=DATE", convertDateFromExchangeToTaskDate(getPropertyIfExists(davPropertySet, "duedate")));
                    vEvent.setPropertyValue("DTSTART;VALUE=DATE", convertDateFromExchangeToTaskDate(getPropertyIfExists(davPropertySet, "startdate")));
                    vEvent.setPropertyValue("COMPLETED;VALUE=DATE", convertDateFromExchangeToTaskDate(getPropertyIfExists(davPropertySet, "datecompleted")));

                } else {
                    vEvent.type = "VEVENT";
                    // check mandatory dtstart value
                    String dtstart = getPropertyIfExists(davPropertySet, "dtstart");
                    if (dtstart != null) {
                        vEvent.setPropertyValue("DTSTART", convertDateFromExchange(dtstart));
                    } else {
                        LOGGER.warn("missing dtstart on item, using fake value. Set davmail.deleteBroken=true to delete broken events");
                        vEvent.setPropertyValue("DTSTART", "20000101T000000Z");
                        deleteBroken();
                    }
                    // same on DTEND
                    String dtend = getPropertyIfExists(davPropertySet, "dtend");
                    if (dtend != null) {
                        vEvent.setPropertyValue("DTEND", convertDateFromExchange(dtend));
                    } else {
                        LOGGER.warn("missing dtend on item, using fake value. Set davmail.deleteBroken=true to delete broken events");
                        vEvent.setPropertyValue("DTEND", "20000101T010000Z");
                        deleteBroken();
                    }
                    vEvent.setPropertyValue("TRANSP", getPropertyIfExists(davPropertySet, "transparent"));
                    vEvent.setPropertyValue("RRULE", getPropertyIfExists(davPropertySet, "rrule"));
                    String exdates = getPropertyIfExists(davPropertySet, "exdate");
                    if (exdates != null) {
                        String[] exdatearray = exdates.split(",");
                        for (String exdate : exdatearray) {
                            vEvent.addPropertyValue("EXDATE",
                                    StringUtil.convertZuluDateTimeToAllDay(convertDateFromExchange(exdate)));
                        }
                    }
                    String organizer = getPropertyIfExists(davPropertySet, "organizer");
                    String organizerEmail = null;
                    if (organizer != null) {
                        InternetAddress organizerAddress = new InternetAddress(organizer);
                        organizerEmail = organizerAddress.getAddress();
                        vEvent.setPropertyValue("ORGANIZER", "MAILTO:" + organizerEmail);
                    }

                    // Parse attendee list
                    String toHeader = getPropertyIfExists(davPropertySet, "to");
                    if (toHeader != null && !toHeader.equals(organizerEmail)) {
                        InternetAddress[] attendees = InternetAddress.parseHeader(toHeader, false);
                        for (InternetAddress attendee : attendees) {
                            if (!attendee.getAddress().equalsIgnoreCase(organizerEmail)) {
                                VProperty vProperty = new VProperty("ATTENDEE", attendee.getAddress());
                                if (attendee.getPersonal() != null) {
                                    vProperty.addParam("CN", attendee.getPersonal());
                                }
                                vEvent.addProperty(vProperty);
                            }
                        }

                    }
                    vEvent.setPropertyValue("X-MICROSOFT-CDO-ALLDAYEVENT",
                            "1".equals(getPropertyIfExists(davPropertySet, "alldayevent")) ? "TRUE" : "FALSE");
                    vEvent.setPropertyValue("X-MICROSOFT-CDO-BUSYSTATUS", getPropertyIfExists(davPropertySet, "busystatus"));

                    if ("1".equals(getPropertyIfExists(davPropertySet, "reminderset"))) {
                        VObject vAlarm = new VObject();
                        vAlarm.type = "VALARM";
                        vAlarm.setPropertyValue("ACTION", "DISPLAY");
                        vAlarm.setPropertyValue("DISPLAY", "Reminder");
                        String reminderdelta = getPropertyIfExists(davPropertySet, "reminderdelta");
                        VProperty vProperty = new VProperty("TRIGGER", "-PT" + reminderdelta + 'M');
                        vProperty.addParam("VALUE", "DURATION");
                        vAlarm.addProperty(vProperty);
                        vEvent.addVObject(vAlarm);
                    }
                }

                localVCalendar.addVObject(vEvent);
                result = localVCalendar.toString().getBytes(StandardCharsets.UTF_8);
            } catch (MessagingException | IOException e) {
                LOGGER.warn("Unable to rebuild event content: " + e.getMessage(), e);
                throw new HttpNotFoundException("Unable to get event " + getName() + " subject: " + subject + " at " + permanentUrl + ": " + e.getMessage());
            }

            return result;
        }

        protected void deleteBroken() {
            // try to delete broken event
            if (Settings.getBooleanProperty("davmail.deleteBroken")) {
                LOGGER.warn("Deleting broken event at: " + permanentUrl);
                try {
                    HttpDelete httpDelete = new HttpDelete(encodeAndFixUrl(permanentUrl));
                    try (CloseableHttpResponse response = httpClientAdapter.execute(httpDelete)) {
                        LOGGER.warn("deleteBroken returned " + response.getStatusLine().getStatusCode());
                    }
                } catch (IOException e) {
                    LOGGER.warn("Unable to delete broken event at: " + permanentUrl);
                }
            }
        }

        protected CloseableHttpResponse internalCreateOrUpdate(String encodedHref, byte[] mimeContent) throws IOException {
            HttpPut httpPut = new HttpPut(encodedHref);
            httpPut.setHeader("Translate", "f");
            httpPut.setHeader("Overwrite", "f");
            if (etag != null) {
                httpPut.setHeader("If-Match", etag);
            }
            if (noneMatch != null) {
                httpPut.setHeader("If-None-Match", noneMatch);
            }
            httpPut.setHeader("Content-Type", "message/rfc822");
            httpPut.setEntity(new ByteArrayEntity(mimeContent, ContentType.getByMimeType("message/rfc822")));
            try (CloseableHttpResponse response = httpClientAdapter.execute(httpPut)) {
                return response;
            }
        }

        /**
         * @inheritDoc
         */
        @Override
        public ItemResult createOrUpdate() throws IOException {
            ItemResult itemResult = new ItemResult();
            if (vCalendar.isTodo()) {
                if ((mailPath + calendarName).equals(folderPath)) {
                    folderPath = mailPath + tasksName;
                }
                String encodedHref = URIUtil.encodePath(getHref());
                Set<PropertyValue> propertyValues = new HashSet<>();
                // set contentclass on create
                if (noneMatch != null) {
                    propertyValues.add(Field.createPropertyValue("contentclass", "urn:content-classes:task"));
                    propertyValues.add(Field.createPropertyValue("outlookmessageclass", "IPM.Task"));
                    propertyValues.add(Field.createPropertyValue("calendaruid", vCalendar.getFirstVeventPropertyValue("UID")));
                }
                propertyValues.add(Field.createPropertyValue("subject", vCalendar.getFirstVeventPropertyValue("SUMMARY")));
                propertyValues.add(Field.createPropertyValue("description", vCalendar.getFirstVeventPropertyValue("DESCRIPTION")));
                propertyValues.add(Field.createPropertyValue("importance", convertPriorityToExchange(vCalendar.getFirstVeventPropertyValue("PRIORITY"))));
                String percentComplete = vCalendar.getFirstVeventPropertyValue("PERCENT-COMPLETE");
                if (percentComplete == null) {
                    percentComplete = "0";
                }
                propertyValues.add(Field.createPropertyValue("percentcomplete", String.valueOf(Double.parseDouble(percentComplete) / 100)));
                String taskStatus = vTodoToTaskStatusMap.get(vCalendar.getFirstVeventPropertyValue("STATUS"));
                propertyValues.add(Field.createPropertyValue("taskstatus", taskStatus));
                propertyValues.add(Field.createPropertyValue("keywords", vCalendar.getFirstVeventPropertyValue("CATEGORIES")));
                propertyValues.add(Field.createPropertyValue("startdate", convertTaskDateToZulu(vCalendar.getFirstVeventPropertyValue("DTSTART"))));
                propertyValues.add(Field.createPropertyValue("duedate", convertTaskDateToZulu(vCalendar.getFirstVeventPropertyValue("DUE"))));
                propertyValues.add(Field.createPropertyValue("datecompleted", convertTaskDateToZulu(vCalendar.getFirstVeventPropertyValue("COMPLETED"))));

                propertyValues.add(Field.createPropertyValue("iscomplete", "2".equals(taskStatus) ? "true" : "false"));
                propertyValues.add(Field.createPropertyValue("commonstart", convertTaskDateToZulu(vCalendar.getFirstVeventPropertyValue("DTSTART"))));
                propertyValues.add(Field.createPropertyValue("commonend", convertTaskDateToZulu(vCalendar.getFirstVeventPropertyValue("DUE"))));

                ExchangePropPatchRequest propPatchMethod = new ExchangePropPatchRequest(encodedHref, propertyValues);
                propPatchMethod.setHeader("Translate", "f");
                if (etag != null) {
                    propPatchMethod.setHeader("If-Match", etag);
                }
                if (noneMatch != null) {
                    propPatchMethod.setHeader("If-None-Match", noneMatch);
                }
                try (CloseableHttpResponse response = httpClientAdapter.execute(propPatchMethod)) {
                    int status = response.getStatusLine().getStatusCode();

                    if (status == HttpStatus.SC_MULTI_STATUS) {
                        Item newItem = getItem(folderPath, itemName);
                        try {
                            itemResult.status = propPatchMethod.getResponseStatusCode();
                        } catch (HttpResponseException e) {
                            throw new IOException(e.getMessage(), e);
                        }
                        itemResult.etag = newItem.etag;
                    } else {
                        itemResult.status = status;
                    }
                }

            } else {
                String encodedHref = URIUtil.encodePath(getHref());
                byte[] mimeContent = createMimeContent();
                HttpResponse httpResponse = internalCreateOrUpdate(encodedHref, mimeContent);
                int status = httpResponse.getStatusLine().getStatusCode();

                if (status == HttpStatus.SC_OK) {
                    LOGGER.debug("Updated event " + encodedHref);
                } else if (status == HttpStatus.SC_CREATED) {
                    LOGGER.debug("Created event " + encodedHref);
                } else if (status == HttpStatus.SC_NOT_FOUND) {
                    LOGGER.debug("Event not found at " + encodedHref + ", searching permanenturl by urlcompname");
                    // failover, search item by urlcompname
                    MultiStatusResponse[] responses = searchItems(folderPath, EVENT_REQUEST_PROPERTIES, DavExchangeSession.this.isEqualTo("urlcompname", convertItemNameToEML(itemName)), FolderQueryTraversal.Shallow, 1);
                    if (responses.length == 1) {
                        encodedHref = getPropertyIfExists(responses[0].getProperties(HttpStatus.SC_OK), "permanenturl");
                        LOGGER.warn("Event found, permanenturl is " + encodedHref);
                        httpResponse = internalCreateOrUpdate(encodedHref, mimeContent);
                        status = httpResponse.getStatusLine().getStatusCode();
                        if (status == HttpStatus.SC_OK) {
                            LOGGER.debug("Updated event " + encodedHref);
                        } else {
                            LOGGER.warn("Unable to create or update event " + status + ' ' + httpResponse.getStatusLine().getReasonPhrase());
                        }
                    }
                } else {
                    LOGGER.warn("Unable to create or update event " + status + ' ' + httpResponse.getStatusLine().getReasonPhrase());
                }

                // 440 means forbidden on Exchange
                if (status == 440) {
                    status = HttpStatus.SC_FORBIDDEN;
                } else if (status == HttpStatus.SC_UNAUTHORIZED && getHref().startsWith("/public")) {
                    LOGGER.warn("Ignore 401 unauthorized on public event");
                    status = HttpStatus.SC_OK;
                }
                itemResult.status = status;
                if (httpResponse.getFirstHeader("GetETag") != null) {
                    itemResult.etag = httpResponse.getFirstHeader("GetETag").getValue();
                }

                // trigger activeSync push event, only if davmail.forceActiveSyncUpdate setting is true
                if ((status == HttpStatus.SC_OK || status == HttpStatus.SC_CREATED) &&
                        (Settings.getBooleanProperty("davmail.forceActiveSyncUpdate"))) {
                    ArrayList<PropEntry> propertyList = new ArrayList<>();
                    // Set contentclass to make ActiveSync happy
                    propertyList.add(Field.createDavProperty("contentclass", contentClass));
                    // ... but also set PR_INTERNET_CONTENT to preserve custom properties
                    propertyList.add(Field.createDavProperty("internetContent", IOUtil.encodeBase64AsString(mimeContent)));
                    HttpProppatch propPatchMethod = new HttpProppatch(encodedHref, propertyList);
                    try (CloseableHttpResponse response = httpClientAdapter.execute(propPatchMethod)) {
                        int patchStatus = response.getStatusLine().getStatusCode();
                        if (patchStatus != HttpStatus.SC_MULTI_STATUS) {
                            LOGGER.warn("Unable to patch event to trigger activeSync push");
                        } else {
                            // need to retrieve new etag
                            Item newItem = getItem(folderPath, itemName);
                            itemResult.etag = newItem.etag;
                        }
                    }
                }
            }
            return itemResult;
        }


    }

    protected Folder buildFolder(MultiStatusResponse entity) throws IOException {
        String href = URIUtil.decode(entity.getHref());
        Folder folder = new Folder();
        DavPropertySet properties = entity.getProperties(HttpStatus.SC_OK);
        folder.displayName = getPropertyIfExists(properties, "displayname");
        folder.folderClass = getPropertyIfExists(properties, "folderclass");
        folder.hasChildren = "1".equals(getPropertyIfExists(properties, "hassubs"));
        folder.noInferiors = "1".equals(getPropertyIfExists(properties, "nosubs"));
        folder.messageCount = getIntPropertyIfExists(properties, "count");
        folder.unreadCount = getIntPropertyIfExists(properties, "unreadcount");
        // fake recent value
        folder.recent = folder.unreadCount;
        folder.ctag = getPropertyIfExists(properties, "contenttag");
        folder.etag = getPropertyIfExists(properties, "lastmodified");

        folder.uidNext = getIntPropertyIfExists(properties, "uidNext");

        // replace well known folder names
        if (inboxUrl != null && href.startsWith(inboxUrl)) {
            folder.folderPath = href.replaceFirst(inboxUrl, INBOX);
        } else if (sentitemsUrl != null && href.startsWith(sentitemsUrl)) {
            folder.folderPath = href.replaceFirst(sentitemsUrl, SENT);
        } else if (draftsUrl != null && href.startsWith(draftsUrl)) {
            folder.folderPath = href.replaceFirst(draftsUrl, DRAFTS);
        } else if (deleteditemsUrl != null && href.startsWith(deleteditemsUrl)) {
            folder.folderPath = href.replaceFirst(deleteditemsUrl, TRASH);
        } else if (calendarUrl != null && href.startsWith(calendarUrl)) {
            folder.folderPath = href.replaceFirst(calendarUrl, CALENDAR);
        } else if (contactsUrl != null && href.startsWith(contactsUrl)) {
            folder.folderPath = href.replaceFirst(contactsUrl, CONTACTS);
        } else {
            int index = href.indexOf(mailPath.substring(0, mailPath.length() - 1));
            if (index >= 0) {
                if (index + mailPath.length() > href.length()) {
                    folder.folderPath = "";
                } else {
                    folder.folderPath = href.substring(index + mailPath.length());
                }
            } else {
                try {
                    java.net.URI folderURI = new java.net.URI(href);
                    folder.folderPath = folderURI.getPath();
                    if (folder.folderPath == null) {
                        throw new DavMailException("EXCEPTION_INVALID_FOLDER_URL", href);
                    }
                } catch (URISyntaxException e) {
                    throw new DavMailException("EXCEPTION_INVALID_FOLDER_URL", href);
                }
            }
        }
        if (folder.folderPath.endsWith("/")) {
            folder.folderPath = folder.folderPath.substring(0, folder.folderPath.length() - 1);
        }
        return folder;
    }

    protected static final Set<String> FOLDER_PROPERTIES = new HashSet<>();

    static {
        FOLDER_PROPERTIES.add("displayname");
        FOLDER_PROPERTIES.add("folderclass");
        FOLDER_PROPERTIES.add("hassubs");
        FOLDER_PROPERTIES.add("nosubs");
        FOLDER_PROPERTIES.add("count");
        FOLDER_PROPERTIES.add("unreadcount");
        FOLDER_PROPERTIES.add("contenttag");
        FOLDER_PROPERTIES.add("lastmodified");
        FOLDER_PROPERTIES.add("uidNext");
    }

    protected static final DavPropertyNameSet FOLDER_PROPERTIES_NAME_SET = new DavPropertyNameSet();

    static {
        for (String attribute : FOLDER_PROPERTIES) {
            FOLDER_PROPERTIES_NAME_SET.add(Field.getPropertyName(attribute));
        }
    }

    /**
     * @inheritDoc
     */
    @Override
    protected Folder internalGetFolder(String folderPath) throws IOException {
        MultiStatus multiStatus = httpClientAdapter.executeDavRequest(new HttpPropfind(
                URIUtil.encodePath(getFolderPath(folderPath)),
                FOLDER_PROPERTIES_NAME_SET, 0));
        MultiStatusResponse[] responses = multiStatus.getResponses();

        Folder folder = null;
        if (responses.length > 0) {
            folder = buildFolder(responses[0]);
            folder.folderPath = folderPath;
        }
        return folder;
    }

    /**
     * @inheritDoc
     */
    @Override
    public List<Folder> getSubFolders(String folderPath, Condition condition, boolean recursive) throws IOException {
        boolean isPublic = folderPath.startsWith("/public");
        FolderQueryTraversal mode = (!isPublic && recursive) ? FolderQueryTraversal.Deep : FolderQueryTraversal.Shallow;
        List<Folder> folders = new ArrayList<>();

        MultiStatusResponse[] responses = searchItems(folderPath, FOLDER_PROPERTIES, and(isTrue("isfolder"), isFalse("ishidden"), condition), mode, 0);

        for (MultiStatusResponse response : responses) {
            Folder folder = buildFolder(response);
            folders.add(buildFolder(response));
            if (isPublic && recursive) {
                getSubFolders(folder.folderPath, condition, recursive);
            }
        }
        return folders;
    }

    /**
     * @inheritDoc
     */
    @Override
    public int createFolder(String folderPath, String folderClass, Map<String, String> properties) throws IOException {
        Set<PropertyValue> propertyValues = new HashSet<>();
        if (properties != null) {
            for (Map.Entry<String, String> entry : properties.entrySet()) {
                propertyValues.add(Field.createPropertyValue(entry.getKey(), entry.getValue()));
            }
        }
        propertyValues.add(Field.createPropertyValue("folderclass", folderClass));

        // standard MkColMethod does not take properties, override ExchangePropPatchRequest instead
        ExchangePropPatchRequest propPatchRequest = new ExchangePropPatchRequest(URIUtil.encodePath(getFolderPath(folderPath)), propertyValues) {
            @Override
            public String getMethod() {
                return "MKCOL";
            }
        };
        int status;
        try (CloseableHttpResponse response = httpClientAdapter.execute(propPatchRequest)) {
            propPatchRequest.handleResponse(response);
            status = response.getStatusLine().getStatusCode();
            if (status == HttpStatus.SC_MULTI_STATUS) {
                status = propPatchRequest.getResponseStatusCode();
            } else if (status == HttpStatus.SC_METHOD_NOT_ALLOWED) {
                LOGGER.info("Folder " + folderPath + " already exists");
            }
        } catch (HttpResponseException e) {
            throw new IOException(e.getMessage(), e);
        }
        LOGGER.debug("Create folder " + folderPath + " returned " + status);
        return status;
    }

    /**
     * @inheritDoc
     */
    @Override
    public int updateFolder(String folderPath, Map<String, String> properties) throws IOException {
        Set<PropertyValue> propertyValues = new HashSet<>();
        if (properties != null) {
            for (Map.Entry<String, String> entry : properties.entrySet()) {
                propertyValues.add(Field.createPropertyValue(entry.getKey(), entry.getValue()));
            }
        }

        ExchangePropPatchRequest propPatchRequest = new ExchangePropPatchRequest(URIUtil.encodePath(getFolderPath(folderPath)), propertyValues);
        try (CloseableHttpResponse response = httpClientAdapter.execute(propPatchRequest)) {
            propPatchRequest.handleResponse(response);
            int status = response.getStatusLine().getStatusCode();
            if (status == HttpStatus.SC_MULTI_STATUS) {
                try {
                    status = propPatchRequest.getResponseStatusCode();
                } catch (HttpResponseException e) {
                    throw new IOException(e.getMessage(), e);
                }
            }

            return status;
        }
    }

    /**
     * @inheritDoc
     */
    @Override
    public void deleteFolder(String folderPath) throws IOException {
        HttpDelete httpDelete = new HttpDelete(URIUtil.encodePath(getFolderPath(folderPath)));
        try (CloseableHttpResponse response = httpClientAdapter.execute(httpDelete)) {
            int status = response.getStatusLine().getStatusCode();
            if (status != HttpStatus.SC_OK && status != HttpStatus.SC_NOT_FOUND) {
                throw HttpClientAdapter.buildHttpResponseException(httpDelete, response);
            }
        }
    }

    /**
     * @inheritDoc
     */
    @Override
    public void moveFolder(String folderPath, String targetPath) throws IOException {
        HttpMove httpMove = new HttpMove(URIUtil.encodePath(getFolderPath(folderPath)),
                URIUtil.encodePath(getFolderPath(targetPath)), false);
        try (CloseableHttpResponse response = httpClientAdapter.execute(httpMove)) {
            int statusCode = response.getStatusLine().getStatusCode();
            if (statusCode == HttpStatus.SC_PRECONDITION_FAILED) {
                throw new HttpPreconditionFailedException(BundleMessage.format("EXCEPTION_UNABLE_TO_MOVE_FOLDER"));
            } else if (statusCode != HttpStatus.SC_CREATED) {
                throw HttpClientAdapter.buildHttpResponseException(httpMove, response);
            } else if (folderPath.equalsIgnoreCase("/users/" + getEmail() + "/calendar")) {
                // calendar renamed, need to reload well known folders
                getWellKnownFolders();
            }
        }
    }

    /**
     * @inheritDoc
     */
    @Override
    public void moveItem(String sourcePath, String targetPath) throws IOException {
        HttpMove httpMove = new HttpMove(URIUtil.encodePath(getFolderPath(sourcePath)),
                URIUtil.encodePath(getFolderPath(targetPath)), false);
        moveItem(httpMove);
    }

    protected void moveItem(HttpMove httpMove) throws IOException {
        try (CloseableHttpResponse response = httpClientAdapter.execute(httpMove)) {
            int statusCode = response.getStatusLine().getStatusCode();
            if (statusCode == HttpStatus.SC_PRECONDITION_FAILED) {
                throw new DavMailException("EXCEPTION_UNABLE_TO_MOVE_ITEM");
            } else if (statusCode != HttpStatus.SC_CREATED && statusCode != HttpStatus.SC_OK) {
                throw HttpClientAdapter.buildHttpResponseException(httpMove, response);
            }
        }
    }

    protected String getPropertyIfExists(DavPropertySet properties, String alias) {
        DavProperty property = properties.get(Field.getResponsePropertyName(alias));
        if (property == null) {
            return null;
        } else {
            Object value = property.getValue();
            if (value instanceof Node) {
                return ((Node) value).getTextContent();
            } else if (value instanceof List) {
                StringBuilder buffer = new StringBuilder();
                for (Object node : (List) value) {
                    if (buffer.length() > 0) {
                        buffer.append(',');
                    }
                    if (node instanceof Node) {
                        // jackrabbit
                        buffer.append(((Node) node).getTextContent());
                    } else {
                        // ExchangeDavMethod
                        buffer.append(node);
                    }
                }
                return buffer.toString();
            } else {
                return (String) value;
            }
        }
    }

    protected String getURLPropertyIfExists(DavPropertySet properties, @SuppressWarnings("SameParameterValue") String alias) throws IOException {
        String result = getPropertyIfExists(properties, alias);
        if (result != null) {
            result = URIUtil.decode(result);
        }
        return result;
    }

    protected int getIntPropertyIfExists(DavPropertySet properties, String alias) {
        DavProperty property = properties.get(Field.getPropertyName(alias));
        if (property == null) {
            return 0;
        } else {
            return Integer.parseInt((String) property.getValue());
        }
    }

    protected long getLongPropertyIfExists(DavPropertySet properties, @SuppressWarnings("SameParameterValue") String alias) {
        DavProperty property = properties.get(Field.getPropertyName(alias));
        if (property == null) {
            return 0;
        } else {
            return Long.parseLong((String) property.getValue());
        }
    }

    protected double getDoublePropertyIfExists(DavPropertySet properties, @SuppressWarnings("SameParameterValue") String alias) {
        DavProperty property = properties.get(Field.getResponsePropertyName(alias));
        if (property == null) {
            return 0;
        } else {
            return Double.parseDouble((String) property.getValue());
        }
    }

    protected byte[] getBinaryPropertyIfExists(DavPropertySet properties, @SuppressWarnings("SameParameterValue") String alias) {
        byte[] property = null;
        String base64Property = getPropertyIfExists(properties, alias);
        if (base64Property != null) {
            property = IOUtil.decodeBase64(base64Property);
        }
        return property;
    }


    protected Message buildMessage(MultiStatusResponse responseEntity) throws IOException {
        Message message = new Message();
        message.messageUrl = URIUtil.decode(responseEntity.getHref());
        DavPropertySet properties = responseEntity.getProperties(HttpStatus.SC_OK);

        message.permanentUrl = getURLPropertyIfExists(properties, "permanenturl");
        message.size = getIntPropertyIfExists(properties, "messageSize");
        message.uid = getPropertyIfExists(properties, "uid");
        message.contentClass = getPropertyIfExists(properties, "contentclass");
        message.imapUid = getLongPropertyIfExists(properties, "imapUid");
        message.read = "1".equals(getPropertyIfExists(properties, "read"));
        message.junk = "1".equals(getPropertyIfExists(properties, "junk"));
        message.flagged = "2".equals(getPropertyIfExists(properties, "flagStatus"));
        message.draft = (getIntPropertyIfExists(properties, "messageFlags") & 8) != 0;
        String lastVerbExecuted = getPropertyIfExists(properties, "lastVerbExecuted");
        message.answered = "102".equals(lastVerbExecuted) || "103".equals(lastVerbExecuted);
        message.forwarded = "104".equals(lastVerbExecuted);
        message.date = convertDateFromExchange(getPropertyIfExists(properties, "date"));
        message.deleted = "1".equals(getPropertyIfExists(properties, "deleted"));

        String lastmodified = convertDateFromExchange(getPropertyIfExists(properties, "lastmodified"));
        message.recent = !message.read && lastmodified != null && lastmodified.equals(message.date);

        message.keywords = getPropertyIfExists(properties, "keywords");

        if (LOGGER.isDebugEnabled()) {
            StringBuilder buffer = new StringBuilder();
            buffer.append("Message");
            if (message.imapUid != 0) {
                buffer.append(" IMAP uid: ").append(message.imapUid);
            }
            if (message.uid != null) {
                buffer.append(" uid: ").append(message.uid);
            }
            buffer.append(" href: ").append(responseEntity.getHref()).append(" permanenturl:").append(message.permanentUrl);
            LOGGER.debug(buffer.toString());
        }
        return message;
    }

    @Override
    public MessageList searchMessages(String folderPath, Set<String> attributes, Condition condition) throws IOException {
        MessageList messages = new MessageList();
        int maxCount = Settings.getIntProperty("davmail.folderSizeLimit", 0);
        MultiStatusResponse[] responses = searchItems(folderPath, attributes, and(isFalse("isfolder"), isFalse("ishidden"), condition), FolderQueryTraversal.Shallow, maxCount);

        for (MultiStatusResponse response : responses) {
            Message message = buildMessage(response);
            message.messageList = messages;
            messages.add(message);
        }
        Collections.sort(messages);
        return messages;
    }

    /**
     * @inheritDoc
     */
    @Override
    public List<ExchangeSession.Contact> searchContacts(String folderPath, Set<String> attributes, Condition condition, int maxCount) throws IOException {
        List<ExchangeSession.Contact> contacts = new ArrayList<>();
        MultiStatusResponse[] responses = searchItems(folderPath, attributes,
                and(isEqualTo("outlookmessageclass", "IPM.Contact"), isFalse("isfolder"), isFalse("ishidden"), condition),
                FolderQueryTraversal.Shallow, maxCount);
        for (MultiStatusResponse response : responses) {
            contacts.add(new Contact(response));
        }
        return contacts;
    }

    /**
     * Common item properties
     */
    protected static final Set<String> ITEM_PROPERTIES = new HashSet<>();

    static {
        ITEM_PROPERTIES.add("etag");
        ITEM_PROPERTIES.add("displayname");
        // calendar CdoInstanceType
        ITEM_PROPERTIES.add("instancetype");
        ITEM_PROPERTIES.add("urlcompname");
        ITEM_PROPERTIES.add("subject");
        ITEM_PROPERTIES.add("contentclass");
    }

    @Override
    protected Set<String> getItemProperties() {
        return ITEM_PROPERTIES;
    }


    /**
     * @inheritDoc
     */
    @Override
    public List<ExchangeSession.Event> getEventMessages(String folderPath) throws IOException {
        return searchEvents(folderPath, ITEM_PROPERTIES,
                and(isEqualTo("contentclass", "urn:content-classes:calendarmessage"),
                        or(isNull("processed"), isFalse("processed"))));
    }


    @Override
    public List<ExchangeSession.Event> searchEvents(String folderPath, Set<String> attributes, Condition condition) throws IOException {
        List<ExchangeSession.Event> events = new ArrayList<>();
        MultiStatusResponse[] responses = searchItems(folderPath, attributes, and(isFalse("isfolder"), isFalse("ishidden"), condition), FolderQueryTraversal.Shallow, 0);
        for (MultiStatusResponse response : responses) {
            String instancetype = getPropertyIfExists(response.getProperties(HttpStatus.SC_OK), "instancetype");
            Event event = new Event(response);
            //noinspection VariableNotUsedInsideIf
            if (instancetype == null) {
                // check ics content
                try {
                    event.getBody();
                    // getBody success => add event or task
                    events.add(event);
                } catch (IOException e) {
                    // invalid event: exclude from list
                    LOGGER.warn("Invalid event " + event.displayName + " found at " + response.getHref(), e);
                }
            } else {
                events.add(event);
            }
        }
        return events;
    }

    @Override
    protected Condition getCalendarItemCondition(Condition dateCondition) {
        boolean caldavEnableLegacyTasks = Settings.getBooleanProperty("davmail.caldavEnableLegacyTasks", false);
        if (caldavEnableLegacyTasks) {
            // return tasks created in calendar folder
            return or(isNull("instancetype"),
                    isEqualTo("instancetype", 1),
                    and(isEqualTo("instancetype", 0), dateCondition));
        } else {
            // instancetype 0 single appointment / 1 master recurring appointment
            return and(or(isEqualTo("outlookmessageclass", "IPM.Appointment"), isEqualTo("outlookmessageclass", "IPM.Appointment.MeetingEvent")),
                    or(isEqualTo("instancetype", 1),
                            and(isEqualTo("instancetype", 0), dateCondition)));
        }
    }

    protected MultiStatusResponse[] searchItems(String folderPath, Set<String> attributes, Condition condition,
                                                FolderQueryTraversal folderQueryTraversal, int maxCount) throws IOException {
        String folderUrl;
        if (folderPath.startsWith("http")) {
            folderUrl = folderPath;
        } else {
            folderUrl = getFolderPath(folderPath);
        }
        StringBuilder searchRequest = new StringBuilder();
        searchRequest.append("SELECT ")
                .append(Field.getRequestPropertyString("permanenturl"));
        if (attributes != null) {
            for (String attribute : attributes) {
                searchRequest.append(',').append(Field.getRequestPropertyString(attribute));
            }
        }
        searchRequest.append(" FROM SCOPE('").append(folderQueryTraversal).append(" TRAVERSAL OF \"").append(folderUrl).append("\"')");
        if (condition != null) {
            searchRequest.append(" WHERE ");
            condition.appendTo(searchRequest);
        }
        searchRequest.append(" ORDER BY ").append(Field.getRequestPropertyString("imapUid")).append(" DESC");
        DavGatewayTray.debug(new BundleMessage("LOG_SEARCH_QUERY", searchRequest));
        MultiStatusResponse[] responses = httpClientAdapter.executeSearchRequest(
                encodeAndFixUrl(folderUrl), searchRequest.toString(), maxCount);
        DavGatewayTray.debug(new BundleMessage("LOG_SEARCH_RESULT", responses.length));
        return responses;
    }

    protected static final Set<String> EVENT_REQUEST_PROPERTIES = new HashSet<>();

    static {
        EVENT_REQUEST_PROPERTIES.add("permanenturl");
        EVENT_REQUEST_PROPERTIES.add("urlcompname");
        EVENT_REQUEST_PROPERTIES.add("etag");
        EVENT_REQUEST_PROPERTIES.add("contentclass");
        EVENT_REQUEST_PROPERTIES.add("displayname");
        EVENT_REQUEST_PROPERTIES.add("subject");
    }

    protected static final DavPropertyNameSet EVENT_REQUEST_PROPERTIES_NAME_SET = new DavPropertyNameSet();

    static {
        for (String attribute : EVENT_REQUEST_PROPERTIES) {
            EVENT_REQUEST_PROPERTIES_NAME_SET.add(Field.getPropertyName(attribute));
        }

    }

    @Override
    public Item getItem(String folderPath, String itemName) throws IOException {
        String emlItemName = convertItemNameToEML(itemName);
        String itemPath = getFolderPath(folderPath) + '/' + emlItemName;
        MultiStatusResponse[] responses = null;
        try {
            HttpPropfind httpPropfind = new HttpPropfind(URIUtil.encodePath(itemPath), EVENT_REQUEST_PROPERTIES_NAME_SET, 0);
            try (CloseableHttpResponse response = httpClientAdapter.execute(httpPropfind)) {
                responses = httpPropfind.getResponseBodyAsMultiStatus(response).getResponses();
            } catch (HttpNotFoundException | DavException e) {
                // ignore
            }
            if (responses == null || responses.length == 0 && isMainCalendar(folderPath)) {
                if (itemName.endsWith(".ics")) {
                    itemName = itemName.substring(0, itemName.length() - 3) + "EML";
                }
                // look for item in tasks folder
                HttpPropfind taskHttpPropfind = new HttpPropfind(URIUtil.encodePath(getFolderPath(TASKS) + '/' + emlItemName), EVENT_REQUEST_PROPERTIES_NAME_SET, 0);
                try (CloseableHttpResponse response = httpClientAdapter.execute(taskHttpPropfind)) {
                    responses = taskHttpPropfind.getResponseBodyAsMultiStatus(response).getResponses();
                } catch (HttpNotFoundException | DavException e) {
                    // ignore
                }
            }
            if (responses == null || responses.length == 0) {
                throw new HttpNotFoundException(itemPath + " not found");
            }
        } catch (HttpNotFoundException e) {
            try {
                LOGGER.debug(itemPath + " not found, searching by urlcompname");
                // failover: try to get event by displayname
                responses = searchItems(folderPath, EVENT_REQUEST_PROPERTIES, isEqualTo("urlcompname", emlItemName), FolderQueryTraversal.Shallow, 1);
                if (responses.length == 0 && isMainCalendar(folderPath)) {
                    responses = searchItems(TASKS, EVENT_REQUEST_PROPERTIES, isEqualTo("urlcompname", emlItemName), FolderQueryTraversal.Shallow, 1);
                }
                if (responses.length == 0) {
                    throw new HttpNotFoundException(itemPath + " not found");
                }
            } catch (HttpNotFoundException e2) {
                LOGGER.debug("last failover: search all items");
                List<ExchangeSession.Event> events = getAllEvents(folderPath);
                for (ExchangeSession.Event event : events) {
                    if (itemName.equals(event.getName())) {
                        HttpPropfind permanentHttpPropfind = new HttpPropfind(encodeAndFixUrl(((DavExchangeSession.Event) event).getPermanentUrl()), EVENT_REQUEST_PROPERTIES_NAME_SET, 0);
                        try (CloseableHttpResponse response = httpClientAdapter.execute(permanentHttpPropfind)) {
                            responses = permanentHttpPropfind.getResponseBodyAsMultiStatus(response).getResponses();
                        } catch (DavException e3) {
                            // ignore
                        }
                        break;
                    }
                }
                if (responses == null || responses.length == 0) {
                    throw new HttpNotFoundException(itemPath + " not found");
                }
                LOGGER.warn("search by urlcompname failed, actual value is " + getPropertyIfExists(responses[0].getProperties(HttpStatus.SC_OK), "urlcompname"));
            }
        }
        // build item
        String contentClass = getPropertyIfExists(responses[0].getProperties(HttpStatus.SC_OK), "contentclass");
        String urlcompname = getPropertyIfExists(responses[0].getProperties(HttpStatus.SC_OK), "urlcompname");
        if ("urn:content-classes:person".equals(contentClass)) {
            // retrieve Contact properties
            List<ExchangeSession.Contact> contacts = searchContacts(folderPath, CONTACT_ATTRIBUTES,
                    isEqualTo("urlcompname", StringUtil.decodeUrlcompname(urlcompname)), 1);
            if (contacts.isEmpty()) {
                LOGGER.warn("Item found, but unable to build contact");
                throw new HttpNotFoundException(itemPath + " not found");
            }
            return contacts.get(0);
        } else if ("urn:content-classes:appointment".equals(contentClass)
                || "urn:content-classes:calendarmessage".equals(contentClass)
                || "urn:content-classes:task".equals(contentClass)) {
            return new Event(responses[0]);
        } else {
            LOGGER.warn("wrong contentclass on item " + itemPath + ": " + contentClass);
            // return item anyway
            return new Event(responses[0]);
        }

    }

    @Override
    public ExchangeSession.ContactPhoto getContactPhoto(ExchangeSession.Contact contact) throws IOException {
        ContactPhoto contactPhoto;
        final HttpGet httpGet = new HttpGet(URIUtil.encodePath(contact.getHref()) + "/ContactPicture.jpg");
        httpGet.setHeader("Translate", "f");
        httpGet.setHeader("Accept-Encoding", "gzip");

        InputStream inputStream = null;
        try (CloseableHttpResponse response = httpClientAdapter.execute(httpGet)) {
            if (HttpClientAdapter.isGzipEncoded(response)) {
                inputStream = (new GZIPInputStream(response.getEntity().getContent()));
            } else {
                inputStream = response.getEntity().getContent();
            }

            contactPhoto = new ContactPhoto();
            contactPhoto.contentType = "image/jpeg";

            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            InputStream partInputStream = inputStream;
            IOUtil.write(partInputStream, baos);
            contactPhoto.content = IOUtil.encodeBase64AsString(baos.toByteArray());
        } finally {
            if (inputStream != null) {
                try {
                    inputStream.close();
                } catch (IOException e) {
                    LOGGER.debug(e);
                }
            }
        }
        return contactPhoto;
    }

    @Override
    public int sendEvent(String icsBody) throws IOException {
        String itemName = UUID.randomUUID() + ".EML";
        byte[] mimeContent = (new Event(getFolderPath(DRAFTS), itemName, "urn:content-classes:calendarmessage", icsBody, null, null)).createMimeContent();
        if (mimeContent == null) {
            // no recipients, cancel
            return HttpStatus.SC_NO_CONTENT;
        } else {
            sendMessage(mimeContent);
            return HttpStatus.SC_OK;
        }
    }

    @Override
    public void deleteItem(String folderPath, String itemName) throws IOException {
        String eventPath = URIUtil.encodePath(getFolderPath(folderPath) + '/' + convertItemNameToEML(itemName));
        HttpDelete httpDelete = new HttpDelete(eventPath);
        int status;
        try (CloseableHttpResponse response = httpClientAdapter.execute(httpDelete)) {
            status = response.getStatusLine().getStatusCode();
        }
        if (status == HttpStatus.SC_NOT_FOUND && isMainCalendar(folderPath)) {
            // retry in tasks folder
            eventPath = URIUtil.encodePath(getFolderPath(TASKS) + '/' + convertItemNameToEML(itemName));
            httpDelete = new HttpDelete(eventPath);
            try (CloseableHttpResponse response = httpClientAdapter.execute(httpDelete)) {
                status = response.getStatusLine().getStatusCode();
            }
        }
        if (status == HttpStatus.SC_NOT_FOUND) {
            LOGGER.debug("Unable to delete " + itemName + ": item not found");
        }
    }

    @Override
    public void processItem(String folderPath, String itemName) throws IOException {
        String eventPath = URIUtil.encodePath(getFolderPath(folderPath) + '/' + convertItemNameToEML(itemName));
        // do not delete calendar messages, mark read and processed
        ArrayList<PropEntry> list = new ArrayList<>();
        list.add(Field.createDavProperty("processed", "true"));
        list.add(Field.createDavProperty("read", "1"));
        HttpProppatch patchMethod = new HttpProppatch(eventPath, list);
        try (CloseableHttpResponse response = httpClientAdapter.execute(patchMethod)) {
            LOGGER.debug("Processed " + itemName + " " + response.getStatusLine().getStatusCode());
        }
    }

    @Override
    public ItemResult internalCreateOrUpdateEvent(String folderPath, String itemName, String contentClass, String icsBody, String etag, String noneMatch) throws IOException {
        return new Event(getFolderPath(folderPath), itemName, contentClass, icsBody, etag, noneMatch).createOrUpdate();
    }

    /**
     * create a fake event to get VTIMEZONE body
     */
    @Override
    protected void loadVtimezone() {
        try {
            // create temporary folder
            String folderPath = getFolderPath("davmailtemp");
            createCalendarFolder(folderPath, null);

            String fakeEventUrl = null;
            if ("Exchange2003".equals(serverVersion)) {
                HttpPost httpPost = new HttpPost(URIUtil.encodePath(folderPath));
                ArrayList<NameValuePair> parameters = new ArrayList<>();
                parameters.add(new BasicNameValuePair("Cmd", "saveappt"));
                parameters.add(new BasicNameValuePair("FORMTYPE", "appointment"));
                httpPost.setEntity(new UrlEncodedFormEntity(parameters, Consts.UTF_8));

                try (CloseableHttpResponse response = httpClientAdapter.execute(httpPost)) {
                    // create fake event
                    int statusCode = response.getStatusLine().getStatusCode();
                    if (statusCode == HttpStatus.SC_OK) {
                        fakeEventUrl = StringUtil.getToken(new BasicResponseHandler().handleResponse(response), "<span id=\"itemHREF\">", "</span>");
                        if (fakeEventUrl != null) {
                            fakeEventUrl = URIUtil.decode(fakeEventUrl);
                        }
                    }
                }
            }
            // failover for Exchange 2007, use PROPPATCH with forced timezone
            if (fakeEventUrl == null) {
                ArrayList<PropEntry> propertyList = new ArrayList<>();
                propertyList.add(Field.createDavProperty("contentclass", "urn:content-classes:appointment"));
                propertyList.add(Field.createDavProperty("outlookmessageclass", "IPM.Appointment"));
                propertyList.add(Field.createDavProperty("instancetype", "0"));

                // get forced timezone id from settings
                String timezoneId = Settings.getProperty("davmail.timezoneId");
                if (timezoneId == null) {
                    // get timezoneid from OWA settings
                    timezoneId = getTimezoneIdFromExchange();
                }
                // without a timezoneId, use Exchange timezone
                if (timezoneId != null) {
                    propertyList.add(Field.createDavProperty("timezoneid", timezoneId));
                }
                String patchMethodUrl = folderPath + '/' + UUID.randomUUID() + ".EML";
                HttpProppatch patchMethod = new HttpProppatch(URIUtil.encodePath(patchMethodUrl), propertyList);
                try (CloseableHttpResponse response = httpClientAdapter.execute(patchMethod)) {
                    int statusCode = response.getStatusLine().getStatusCode();
                    if (statusCode == HttpStatus.SC_MULTI_STATUS) {
                        fakeEventUrl = patchMethodUrl;
                    }
                }
            }
            if (fakeEventUrl != null) {
                // get fake event body
                HttpGet httpGet = new HttpGet(URIUtil.encodePath(fakeEventUrl));
                httpGet.setHeader("Translate", "f");
                try (CloseableHttpResponse response = httpClientAdapter.execute(httpGet)) {
                    this.vTimezone = new VObject("BEGIN:VTIMEZONE" +
                            StringUtil.getToken(new BasicResponseHandler().handleResponse(response), "BEGIN:VTIMEZONE", "END:VTIMEZONE") +
                            "END:VTIMEZONE\r\n");
                }
            }

            // delete temporary folder
            deleteFolder("davmailtemp");
        } catch (IOException e) {
            LOGGER.warn("Unable to get VTIMEZONE info: " + e, e);
        }
    }

    protected String getTimezoneIdFromExchange() {
        String timezoneId = null;
        String timezoneName = null;
        try {
            Set<String> attributes = new HashSet<>();
            attributes.add("roamingdictionary");

            MultiStatusResponse[] responses = searchItems("/users/" + getEmail() + "/NON_IPM_SUBTREE", attributes, isEqualTo("messageclass", "IPM.Configuration.OWA.UserOptions"), DavExchangeSession.FolderQueryTraversal.Deep, 1);
            if (responses.length == 1) {
                byte[] roamingdictionary = getBinaryPropertyIfExists(responses[0].getProperties(HttpStatus.SC_OK), "roamingdictionary");
                if (roamingdictionary != null) {
                    timezoneName = getTimezoneNameFromRoamingDictionary(roamingdictionary);
                    if (timezoneName != null) {
                        timezoneId = ResourceBundle.getBundle("timezoneids").getString(timezoneName);
                    }
                }
            }
        } catch (MissingResourceException e) {
            LOGGER.warn("Unable to retrieve Exchange timezone id for name " + timezoneName);
        } catch (IOException e) {
            LOGGER.warn("Unable to retrieve Exchange timezone id: " + e.getMessage(), e);
        }
        return timezoneId;
    }

    protected String getTimezoneNameFromRoamingDictionary(byte[] roamingdictionary) {
        String timezoneName = null;
        XMLStreamReader reader;
        try {
            reader = XMLStreamUtil.createXMLStreamReader(roamingdictionary);
            while (reader.hasNext()) {
                reader.next();
                if (XMLStreamUtil.isStartTag(reader, "e")
                        && "18-timezone".equals(reader.getAttributeValue(null, "k"))) {
                    String value = reader.getAttributeValue(null, "v");
                    if (value != null && value.startsWith("18-")) {
                        timezoneName = value.substring(3);
                    }
                }
            }

        } catch (XMLStreamException e) {
            LOGGER.error("Error while parsing RoamingDictionary: " + e, e);
        }
        return timezoneName;
    }

    @Override
    protected Contact buildContact(String folderPath, String itemName, Map<String, String> properties, String etag, String noneMatch) {
        return new Contact(getFolderPath(folderPath), itemName, properties, etag, noneMatch);
    }

    protected List<PropEntry> buildProperties(Map<String, String> properties) {
        ArrayList<PropEntry> list = new ArrayList<>();
        if (properties != null) {
            for (Map.Entry<String, String> entry : properties.entrySet()) {
                if ("read".equals(entry.getKey())) {
                    list.add(Field.createDavProperty("read", entry.getValue()));
                } else if ("junk".equals(entry.getKey())) {
                    list.add(Field.createDavProperty("junk", entry.getValue()));
                } else if ("flagged".equals(entry.getKey())) {
                    list.add(Field.createDavProperty("flagStatus", entry.getValue()));
                } else if ("answered".equals(entry.getKey())) {
                    list.add(Field.createDavProperty("lastVerbExecuted", entry.getValue()));
                    if ("102".equals(entry.getValue())) {
                        list.add(Field.createDavProperty("iconIndex", "261"));
                    }
                } else if ("forwarded".equals(entry.getKey())) {
                    list.add(Field.createDavProperty("lastVerbExecuted", entry.getValue()));
                    if ("104".equals(entry.getValue())) {
                        list.add(Field.createDavProperty("iconIndex", "262"));
                    }
                } else if ("bcc".equals(entry.getKey())) {
                    list.add(Field.createDavProperty("bcc", entry.getValue()));
                } else if ("deleted".equals(entry.getKey())) {
                    list.add(Field.createDavProperty("deleted", entry.getValue()));
                } else if ("datereceived".equals(entry.getKey())) {
                    list.add(Field.createDavProperty("datereceived", entry.getValue()));
                } else if ("keywords".equals(entry.getKey())) {
                    list.add(Field.createDavProperty("keywords", entry.getValue()));
                }
            }
        }
        return list;
    }

    /**
     * Create message in specified folder.
     * Will overwrite an existing message with same messageName in the same folder
     *
     * @param folderPath  Exchange folder path
     * @param messageName message name
     * @param properties  message properties (flags)
     * @param mimeMessage MIME message
     * @throws IOException when unable to create message
     */
    @Override
    public Message createMessage(String folderPath, String messageName, HashMap<String, String> properties, MimeMessage mimeMessage) throws IOException {
        String messageUrl = URIUtil.encodePathQuery(getFolderPath(folderPath) + '/' + messageName);

        List<PropEntry> davProperties = buildProperties(properties);

        if (properties != null && properties.containsKey("draft")) {
            // note: draft is readonly after create, create the message first with requested messageFlags
            davProperties.add(Field.createDavProperty("messageFlags", properties.get("draft")));
        }
        if (properties != null && properties.containsKey("mailOverrideFormat")) {
            davProperties.add(Field.createDavProperty("mailOverrideFormat", properties.get("mailOverrideFormat")));
        }
        if (properties != null && properties.containsKey("messageFormat")) {
            davProperties.add(Field.createDavProperty("messageFormat", properties.get("messageFormat")));
        }
        if (!davProperties.isEmpty()) {
            HttpProppatch httpProppatch = new HttpProppatch(messageUrl, davProperties);
            try (CloseableHttpResponse response = httpClientAdapter.execute(httpProppatch)) {
                // update message with blind carbon copy and other flags
                int statusCode = response.getStatusLine().getStatusCode();
                if (statusCode != HttpStatus.SC_MULTI_STATUS) {
                    throw new DavMailException("EXCEPTION_UNABLE_TO_CREATE_MESSAGE", messageUrl, statusCode, ' ', response.getStatusLine().getReasonPhrase());
                }

            }
        }

        // update message body
        HttpPut putmethod = new HttpPut(messageUrl);
        putmethod.setHeader("Translate", "f");
        putmethod.setHeader("Content-Type", "message/rfc822");

        try {
            // use same encoding as client socket reader
            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            mimeMessage.writeTo(baos);
            baos.close();
            putmethod.setEntity(new ByteArrayEntity(baos.toByteArray()));

            int code;
            String reasonPhrase;
            try (CloseableHttpResponse response = httpClientAdapter.execute(putmethod)) {
                code = response.getStatusLine().getStatusCode();
                reasonPhrase = response.getStatusLine().getReasonPhrase();
            }

            // workaround for misconfigured Exchange server
            if (code == HttpStatus.SC_NOT_ACCEPTABLE) {
                LOGGER.warn("Draft message creation failed, failover to property update. Note: attachments are lost");

                ArrayList<PropEntry> propertyList = new ArrayList<>();
                propertyList.add(Field.createDavProperty("to", mimeMessage.getHeader("to", ",")));
                propertyList.add(Field.createDavProperty("cc", mimeMessage.getHeader("cc", ",")));
                propertyList.add(Field.createDavProperty("message-id", mimeMessage.getHeader("message-id", ",")));

                MimePart mimePart = mimeMessage;
                if (mimeMessage.getContent() instanceof MimeMultipart) {
                    MimeMultipart multiPart = (MimeMultipart) mimeMessage.getContent();
                    for (int i = 0; i < multiPart.getCount(); i++) {
                        String contentType = multiPart.getBodyPart(i).getContentType();
                        if (contentType.startsWith("text/")) {
                            mimePart = (MimePart) multiPart.getBodyPart(i);
                            break;
                        }
                    }
                }

                String contentType = mimePart.getContentType();

                if (contentType.startsWith("text/plain")) {
                    propertyList.add(Field.createDavProperty("description", (String) mimePart.getContent()));
                } else if (contentType.startsWith("text/html")) {
                    propertyList.add(Field.createDavProperty("htmldescription", (String) mimePart.getContent()));
                } else {
                    LOGGER.warn("Unsupported content type: " + contentType.replaceAll("[\n\r\t]", "_") + " message body will be empty");
                }

                propertyList.add(Field.createDavProperty("subject", mimeMessage.getHeader("subject", ",")));
                HttpProppatch propPatchMethod = new HttpProppatch(messageUrl, propertyList);
                try (CloseableHttpResponse response = httpClientAdapter.execute(propPatchMethod)) {
                    int patchStatus = response.getStatusLine().getStatusCode();
                    if (patchStatus == HttpStatus.SC_MULTI_STATUS) {
                        code = HttpStatus.SC_OK;
                    }
                }
            }


            if (code != HttpStatus.SC_OK && code != HttpStatus.SC_CREATED) {

                // first delete draft message
                if (!davProperties.isEmpty()) {
                    HttpDelete httpDelete = new HttpDelete(messageUrl);
                    try (CloseableHttpResponse response = httpClientAdapter.execute(httpDelete)) {
                        int status = response.getStatusLine().getStatusCode();
                        if (status != HttpStatus.SC_OK && status != HttpStatus.SC_NOT_FOUND) {
                            throw HttpClientAdapter.buildHttpResponseException(httpDelete, response);
                        }
                    } catch (IOException e) {
                        LOGGER.warn("Unable to delete draft message");
                    }
                }
                if (code == HttpStatus.SC_INSUFFICIENT_STORAGE) {
                    throw new InsufficientStorageException(reasonPhrase);
                } else {
                    throw new DavMailException("EXCEPTION_UNABLE_TO_CREATE_MESSAGE", messageUrl, code, ' ', reasonPhrase);
                }
            }
        } catch (MessagingException e) {
            throw new IOException(e.getMessage());
        } finally {
            putmethod.releaseConnection();
        }

        try {
            // need to update bcc after put
            if (mimeMessage.getHeader("Bcc") != null) {
                davProperties = new ArrayList<>();
                davProperties.add(Field.createDavProperty("bcc", mimeMessage.getHeader("Bcc", ",")));
                HttpProppatch httpProppatch = new HttpProppatch(messageUrl, davProperties);
                // update message with blind carbon copy
                try (CloseableHttpResponse response = httpClientAdapter.execute(httpProppatch)) {
                    int statusCode = response.getStatusLine().getStatusCode();
                    if (statusCode != HttpStatus.SC_MULTI_STATUS) {
                        throw new DavMailException("EXCEPTION_UNABLE_TO_CREATE_MESSAGE", messageUrl, statusCode, ' ', response.getStatusLine().getReasonPhrase());
                    }
                }
            }
        } catch (MessagingException e) {
            throw new IOException(e.getMessage());
        }
        // fetch after create not implemented
        return null;
    }

    /**
     * @inheritDoc
     */
    @Override
    public void updateMessage(ExchangeSession.Message message, Map<String, String> properties) throws IOException {
        HttpProppatch patchMethod = new HttpProppatch(encodeAndFixUrl(message.permanentUrl), buildProperties(properties)) {
            @Override
            public MultiStatus getResponseBodyAsMultiStatus(HttpResponse response) {
                // ignore response body, sometimes invalid with exchange mapi properties
                throw new UnsupportedOperationException();
            }
        };
        try (CloseableHttpResponse response = httpClientAdapter.execute(patchMethod)) {
            int statusCode = response.getStatusLine().getStatusCode();
            if (statusCode != HttpStatus.SC_MULTI_STATUS) {
                throw new DavMailException("EXCEPTION_UNABLE_TO_UPDATE_MESSAGE");
            }
        }
    }

    /**
     * @inheritDoc
     */
    @Override
    public void deleteMessage(ExchangeSession.Message message) throws IOException {
        LOGGER.debug("Delete " + message.permanentUrl + " (" + message.messageUrl + ')');
        HttpDelete httpDelete = new HttpDelete(encodeAndFixUrl(message.permanentUrl));
        try (CloseableHttpResponse response = httpClientAdapter.execute(httpDelete)) {
            int status = response.getStatusLine().getStatusCode();
            if (status != HttpStatus.SC_OK && status != HttpStatus.SC_NOT_FOUND) {
                throw HttpClientAdapter.buildHttpResponseException(httpDelete, response);
            }
        }
    }

    /**
     * Send message.
     *
     * @param messageBody MIME message body
     * @throws IOException on error
     */
    public void sendMessage(byte[] messageBody) throws IOException {
        try {
            sendMessage(new MimeMessage(null, new SharedByteArrayInputStream(messageBody)));
        } catch (MessagingException e) {
            throw new IOException(e.getMessage());
        }
    }

    //protected static final long MAPI_SEND_NO_RICH_INFO = 0x00010000L;
    protected static final long ENCODING_PREFERENCE = 0x00020000L;
    protected static final long ENCODING_MIME = 0x00040000L;
    //protected static final long BODY_ENCODING_HTML = 0x00080000L;
    protected static final long BODY_ENCODING_TEXT_AND_HTML = 0x00100000L;
    //protected static final long MAC_ATTACH_ENCODING_UUENCODE = 0x00200000L;
    //protected static final long MAC_ATTACH_ENCODING_APPLESINGLE = 0x00400000L;
    //protected static final long MAC_ATTACH_ENCODING_APPLEDOUBLE = 0x00600000L;
    //protected static final long OOP_DONT_LOOKUP = 0x10000000L;

    @Override
    public void sendMessage(MimeMessage mimeMessage) throws IOException {
        try {
            // need to create draft first
            String itemName = UUID.randomUUID() + ".EML";
            HashMap<String, String> properties = new HashMap<>();
            properties.put("draft", "9");
            String contentType = mimeMessage.getContentType();
            if (contentType != null && contentType.startsWith("text/plain")) {
                properties.put("messageFormat", "1");
            } else {
                properties.put("mailOverrideFormat", String.valueOf(ENCODING_PREFERENCE | ENCODING_MIME | BODY_ENCODING_TEXT_AND_HTML));
                properties.put("messageFormat", "2");
            }
            createMessage(DRAFTS, itemName, properties, mimeMessage);
            HttpMove httpMove = new HttpMove(URIUtil.encodePath(getFolderPath(DRAFTS + '/' + itemName)),
                    URIUtil.encodePath(getFolderPath(SENDMSG)), false);
            // set header if saveInSent is disabled
            if (!Settings.getBooleanProperty("davmail.smtpSaveInSent", true)) {
                httpMove.setHeader("Saveinsent", "f");
            }
            moveItem(httpMove);
        } catch (MessagingException e) {
            throw new IOException(e.getMessage());
        }
    }

    // wrong hostname fix flag
    protected boolean restoreHostName;

    /**
     * @inheritDoc
     */
    @Override
    protected byte[] getContent(ExchangeSession.Message message) throws IOException {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        InputStream contentInputStream;
        try {
            try {
                try {
                    contentInputStream = getContentInputStream(message.messageUrl);
                } catch (UnknownHostException e) {
                    // failover for misconfigured Exchange server, replace host name in url
                    restoreHostName = true;
                    contentInputStream = getContentInputStream(message.messageUrl);
                }
            } catch (HttpNotFoundException e) {
                LOGGER.debug("Message not found at: " + message.messageUrl + ", retrying with permanenturl");
                contentInputStream = getContentInputStream(message.permanentUrl);
            }

            try {
                IOUtil.write(contentInputStream, baos);
            } finally {
                contentInputStream.close();
            }

        } catch (LoginTimeoutException | SocketException e) {
            // throw error on expired session
            LOGGER.warn(e.getMessage());
            throw e;
        } // throw error on broken connection
        catch (IOException e) {
            LOGGER.warn("Broken message at: " + message.messageUrl + " permanentUrl: " + message.permanentUrl + ", trying to rebuild from properties");

            try {
                DavPropertyNameSet messageProperties = new DavPropertyNameSet();
                messageProperties.add(Field.getPropertyName("contentclass"));
                messageProperties.add(Field.getPropertyName("message-id"));
                messageProperties.add(Field.getPropertyName("from"));
                messageProperties.add(Field.getPropertyName("to"));
                messageProperties.add(Field.getPropertyName("cc"));
                messageProperties.add(Field.getPropertyName("subject"));
                messageProperties.add(Field.getPropertyName("date"));
                messageProperties.add(Field.getPropertyName("htmldescription"));
                messageProperties.add(Field.getPropertyName("body"));
                HttpPropfind httpPropfind = new HttpPropfind(encodeAndFixUrl(message.permanentUrl), messageProperties, 0);
                try (CloseableHttpResponse response = httpClientAdapter.execute(httpPropfind)) {
                    MultiStatus responses = httpPropfind.getResponseBodyAsMultiStatus(response);
                    if (responses.getResponses().length > 0) {
                        MimeMessage mimeMessage = new MimeMessage((Session) null);

                        DavPropertySet properties = responses.getResponses()[0].getProperties(HttpStatus.SC_OK);
                        String propertyValue = getPropertyIfExists(properties, "contentclass");
                        if (propertyValue != null) {
                            mimeMessage.addHeader("Content-class", propertyValue);
                        }
                        propertyValue = getPropertyIfExists(properties, "date");
                        if (propertyValue != null) {
                            mimeMessage.setSentDate(parseDateFromExchange(propertyValue));
                        }
                        propertyValue = getPropertyIfExists(properties, "from");
                        if (propertyValue != null) {
                            mimeMessage.addHeader("From", propertyValue);
                        }
                        propertyValue = getPropertyIfExists(properties, "to");
                        if (propertyValue != null) {
                            mimeMessage.addHeader("To", propertyValue);
                        }
                        propertyValue = getPropertyIfExists(properties, "cc");
                        if (propertyValue != null) {
                            mimeMessage.addHeader("Cc", propertyValue);
                        }
                        propertyValue = getPropertyIfExists(properties, "subject");
                        if (propertyValue != null) {
                            mimeMessage.setSubject(propertyValue);
                        }
                        propertyValue = getPropertyIfExists(properties, "htmldescription");
                        if (propertyValue != null) {
                            mimeMessage.setContent(propertyValue, "text/html; charset=UTF-8");
                        } else {
                            propertyValue = getPropertyIfExists(properties, "body");
                            if (propertyValue != null) {
                                mimeMessage.setText(propertyValue);
                            }
                        }
                        mimeMessage.writeTo(baos);
                    }
                }
                if (LOGGER.isDebugEnabled()) {
                    LOGGER.debug("Rebuilt message content: " + new String(baos.toByteArray(), StandardCharsets.UTF_8));
                }
            } catch (IOException | DavException | MessagingException e2) {
                LOGGER.warn(e2);
            }
            // other exception
            if (baos.size() == 0 && Settings.getBooleanProperty("davmail.deleteBroken")) {
                LOGGER.warn("Deleting broken message at: " + message.messageUrl + " permanentUrl: " + message.permanentUrl);
                try {
                    message.delete();
                } catch (IOException ioe) {
                    LOGGER.warn("Unable to delete broken message at: " + message.permanentUrl);
                }
                throw e;
            }
        }

        return baos.toByteArray();
    }

    /**
     * sometimes permanenturis inside items are wrong after an Exchange version migration
     * need to restore base uri to actual public Exchange uri
     *
     * @param url input uri
     * @return fixed uri
     * @throws IOException on error
     */
    protected String encodeAndFixUrl(String url) throws IOException {
        String fixedurl = URIUtil.encodePath(url);
        // sometimes permanenturis inside items are wrong after an Exchange version migration
        // need to restore base uri to actual public Exchange uri
        if (restoreHostName && fixedurl.startsWith("http")) {
            try {
                return URIUtils.rewriteURI(new java.net.URI(fixedurl), URIUtils.extractHost(httpClientAdapter.getUri())).toString();
            } catch (URISyntaxException e) {
                throw new IOException(e.getMessage(), e);
            }
        }
        return fixedurl;
    }

    protected InputStream getContentInputStream(String url) throws IOException {
        String encodedUrl = encodeAndFixUrl(url);

        final HttpGet httpGet = new HttpGet(encodedUrl);
        httpGet.setHeader("Content-Type", "text/xml; charset=utf-8");
        httpGet.setHeader("Translate", "f");
        httpGet.setHeader("Accept-Encoding", "gzip");

        InputStream inputStream;
        try (CloseableHttpResponse response = httpClientAdapter.execute(httpGet)) {
            if (HttpClientAdapter.isGzipEncoded(response)) {
                inputStream = new GZIPInputStream(response.getEntity().getContent());
            } else {
                inputStream = response.getEntity().getContent();
            }
            inputStream = new FilterInputStream(inputStream) {
                int totalCount;
                int lastLogCount;

                @Override
                public int read(byte[] buffer, int offset, int length) throws IOException {
                    int count = super.read(buffer, offset, length);
                    totalCount += count;
                    if (totalCount - lastLogCount > 1024 * 128) {
                        DavGatewayTray.debug(new BundleMessage("LOG_DOWNLOAD_PROGRESS", String.valueOf(totalCount / 1024), httpGet.getURI()));
                        DavGatewayTray.switchIcon();
                        lastLogCount = totalCount;
                    }
                    return count;
                }

                @Override
                public void close() throws IOException {
                    try {
                        super.close();
                    } finally {
                        httpGet.releaseConnection();
                    }
                }
            };

        } catch (IOException e) {
            LOGGER.warn("Unable to retrieve message at: " + url);
            throw e;
        }
        return inputStream;
    }

    /**
     * @inheritDoc
     */
    @Override
    public void moveMessage(ExchangeSession.Message message, String targetFolder) throws IOException {
        try {
            moveMessage(message.permanentUrl, targetFolder);
        } catch (HttpNotFoundException e) {
            LOGGER.debug("404 not found at permanenturl: " + message.permanentUrl + ", retry with messageurl");
            moveMessage(message.messageUrl, targetFolder);
        }
    }

    protected void moveMessage(String sourceUrl, String targetFolder) throws IOException {
        String targetPath = URIUtil.encodePath(getFolderPath(targetFolder)) + '/' + UUID.randomUUID();
        HttpMove method = new HttpMove(URIUtil.encodePath(sourceUrl), targetPath, false);
        // allow rename if a message with the same name exists
        method.setHeader("Allow-Rename", "t");
        try (CloseableHttpResponse response = httpClientAdapter.execute(method)) {
            int statusCode = response.getStatusLine().getStatusCode();
            if (statusCode == HttpStatus.SC_PRECONDITION_FAILED ||
                    statusCode == HttpStatus.SC_CONFLICT) {
                throw new DavMailException("EXCEPTION_UNABLE_TO_MOVE_MESSAGE");
            } else if (statusCode != HttpStatus.SC_CREATED) {
                throw HttpClientAdapter.buildHttpResponseException(method, response);
            }
        } finally {
            method.releaseConnection();
        }
    }

    /**
     * @inheritDoc
     */
    @Override
    public void copyMessage(ExchangeSession.Message message, String targetFolder) throws IOException {
        try {
            copyMessage(message.permanentUrl, targetFolder);
        } catch (HttpNotFoundException e) {
            LOGGER.debug("404 not found at permanenturl: " + message.permanentUrl + ", retry with messageurl");
            copyMessage(message.messageUrl, targetFolder);
        }
    }

    protected void copyMessage(String sourceUrl, String targetFolder) throws IOException {
        String targetPath = URIUtil.encodePath(getFolderPath(targetFolder)) + '/' + UUID.randomUUID();
        HttpCopy httpCopy = new HttpCopy(URIUtil.encodePath(sourceUrl), targetPath, false, false);
        // allow rename if a message with the same name exists
        httpCopy.addHeader("Allow-Rename", "t");
        try (CloseableHttpResponse response = httpClientAdapter.execute(httpCopy)) {
            int statusCode = response.getStatusLine().getStatusCode();
            if (statusCode == HttpStatus.SC_PRECONDITION_FAILED) {
                throw new DavMailException("EXCEPTION_UNABLE_TO_COPY_MESSAGE");
            } else if (statusCode != HttpStatus.SC_CREATED) {
                throw HttpClientAdapter.buildHttpResponseException(httpCopy, response);
            }
        }
    }

    @Override
    protected void moveToTrash(ExchangeSession.Message message) throws IOException {
        String destination = URIUtil.encodePath(deleteditemsUrl) + '/' + UUID.randomUUID();
        LOGGER.debug("Deleting : " + message.permanentUrl + " to " + destination);
        HttpMove method = new HttpMove(encodeAndFixUrl(message.permanentUrl), destination, false);
        method.addHeader("Allow-rename", "t");

        try (CloseableHttpResponse response = httpClientAdapter.execute(method)) {
            int status = response.getStatusLine().getStatusCode();
            // do not throw error if already deleted
            if (status != HttpStatus.SC_CREATED && status != HttpStatus.SC_NOT_FOUND) {
                throw HttpClientAdapter.buildHttpResponseException(method, response);
            }
            if (response.getFirstHeader("Location") != null) {
                destination = method.getFirstHeader("Location").getValue();
            }
        }

        LOGGER.debug("Deleted to :" + destination);
    }

    protected String getItemProperty(String permanentUrl, String propertyName) throws IOException, DavException {
        String result = null;
        DavPropertyNameSet davPropertyNameSet = new DavPropertyNameSet();
        davPropertyNameSet.add(Field.getPropertyName(propertyName));
        HttpPropfind propFindMethod = new HttpPropfind(encodeAndFixUrl(permanentUrl), davPropertyNameSet, 0);
        MultiStatus responses;
        try (CloseableHttpResponse response = httpClientAdapter.execute(propFindMethod)) {
            responses = propFindMethod.getResponseBodyAsMultiStatus(response);
        } catch (UnknownHostException e) {
            // failover for misconfigured Exchange server, replace host name in url
            restoreHostName = true;
            propFindMethod = new HttpPropfind(encodeAndFixUrl(permanentUrl), davPropertyNameSet, 0);
            try (CloseableHttpResponse response = httpClientAdapter.execute(propFindMethod)) {
                responses = propFindMethod.getResponseBodyAsMultiStatus(response);
            }
        }

        if (responses.getResponses().length > 0) {
            DavPropertySet properties = responses.getResponses()[0].getProperties(HttpStatus.SC_OK);
            result = getPropertyIfExists(properties, propertyName);
        }

        return result;
    }

    protected String convertDateFromExchange(String exchangeDateValue) throws DavMailException {
        String zuluDateValue = null;
        if (exchangeDateValue != null) {
            try {
                zuluDateValue = getZuluDateFormat().format(getExchangeZuluDateFormatMillisecond().parse(exchangeDateValue));
            } catch (ParseException e) {
                throw new DavMailException("EXCEPTION_INVALID_DATE", exchangeDateValue);
            }
        }
        return zuluDateValue;
    }

    protected static final Map<String, String> importanceToPriorityMap = new HashMap<>();

    static {
        importanceToPriorityMap.put("high", "1");
        importanceToPriorityMap.put("normal", "5");
        importanceToPriorityMap.put("low", "9");
    }

    protected static final Map<String, String> priorityToImportanceMap = new HashMap<>();

    static {
        priorityToImportanceMap.put("1", "high");
        priorityToImportanceMap.put("5", "normal");
        priorityToImportanceMap.put("9", "low");
    }

    protected String convertPriorityFromExchange(String exchangeImportanceValue) {
        String value = null;
        if (exchangeImportanceValue != null) {
            value = importanceToPriorityMap.get(exchangeImportanceValue);
        }
        return value;
    }

    protected String convertPriorityToExchange(String vTodoPriorityValue) {
        String value = null;
        if (vTodoPriorityValue != null) {
            value = priorityToImportanceMap.get(vTodoPriorityValue);
        }
        return value;
    }


    @Override
    public void close() {
        httpClientAdapter.close();
    }

    /**
     * Format date to exchange search format.
     *
     * @param date date object
     * @return formatted search date
     */
    @Override
    public String formatSearchDate(Date date) {
        SimpleDateFormat dateFormatter = new SimpleDateFormat(YYYY_MM_DD_HH_MM_SS, Locale.ENGLISH);
        dateFormatter.setTimeZone(GMT_TIMEZONE);
        return dateFormatter.format(date);
    }

    protected String convertTaskDateToZulu(String value) {
        String result = null;
        if (value != null && !value.isEmpty()) {
            try {
                SimpleDateFormat parser = ExchangeSession.getExchangeDateFormat(value);

                Calendar calendarValue = Calendar.getInstance(GMT_TIMEZONE);
                calendarValue.setTime(parser.parse(value));
                // zulu time: add 12 hours
                if (value.length() == 16) {
                    calendarValue.add(Calendar.HOUR, 12);
                }
                calendarValue.set(Calendar.HOUR, 0);
                calendarValue.set(Calendar.MINUTE, 0);
                calendarValue.set(Calendar.SECOND, 0);
                result = ExchangeSession.getExchangeZuluDateFormatMillisecond().format(calendarValue.getTime());
            } catch (ParseException e) {
                LOGGER.warn("Invalid date: " + value);
            }
        }

        return result;
    }

    protected String convertDateFromExchangeToTaskDate(String exchangeDateValue) throws DavMailException {
        String result = null;
        if (exchangeDateValue != null) {
            try {
                SimpleDateFormat dateFormat = new SimpleDateFormat("yyyyMMdd", Locale.ENGLISH);
                dateFormat.setTimeZone(GMT_TIMEZONE);
                result = dateFormat.format(getExchangeZuluDateFormatMillisecond().parse(exchangeDateValue));
            } catch (ParseException e) {
                throw new DavMailException("EXCEPTION_INVALID_DATE", exchangeDateValue);
            }
        }
        return result;
    }

    protected Date parseDateFromExchange(String exchangeDateValue) throws DavMailException {
        Date result = null;
        if (exchangeDateValue != null) {
            try {
                result = getExchangeZuluDateFormatMillisecond().parse(exchangeDateValue);
            } catch (ParseException e) {
                throw new DavMailException("EXCEPTION_INVALID_DATE", exchangeDateValue);
            }
        }
        return result;
    }
}
