/*
 * Copyright (C) 2008-2009 Marc Blank
 * Licensed to The Android Open Source Project.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.exchange;

import com.android.email.mail.MessagingException;
import com.android.email.provider.EmailContent;
import com.android.email.provider.EmailContent.Account;
import com.android.email.provider.EmailContent.Attachment;
import com.android.email.provider.EmailContent.HostAuth;
import com.android.email.provider.EmailContent.HostAuthColumns;
import com.android.email.provider.EmailContent.Mailbox;
import com.android.email.provider.EmailContent.MailboxColumns;
import com.android.email.provider.EmailContent.Message;
import com.android.email.provider.EmailContent.MessageColumns;
import com.android.email.provider.EmailContent.SyncColumns;
import com.android.exchange.utility.FileLogger;

import android.accounts.AccountManager;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.BroadcastReceiver;
import android.content.ContentResolver;
import android.content.ContentValues;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.database.ContentObserver;
import android.database.Cursor;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.Uri;
import android.net.NetworkInfo.State;
import android.os.Bundle;
import android.os.Debug;
import android.os.Handler;
import android.os.IBinder;
import android.os.PowerManager;
import android.os.RemoteCallbackList;
import android.os.RemoteException;
import android.os.PowerManager.WakeLock;
import android.util.Log;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

/**
 * The SyncManager handles all aspects of starting, maintaining, and stopping the various sync
 * adapters used by Exchange.  However, it is capable of handing any kind of email sync, and it
 * would be appropriate to use for IMAP push, when that functionality is added to the Email
 * application.
 *
 * The Email application communicates with EAS sync adapters via SyncManager's binder interface,
 * which exposes UI-related functionality to the application (see the definitions below)
 *
 * SyncManager uses ContentObservers to detect changes to accounts, mailboxes, and messages in
 * order to maintain proper 2-way syncing of data.  (More documentation to follow)
 *
 */
public class SyncManager extends Service implements Runnable {

    private static final String TAG = "EAS SyncManager";

    // The SyncManager's mailbox "id"
    private static final int SYNC_MANAGER_ID = -1;

    private static final int SECONDS = 1000;
    private static final int MINUTES = 60*SECONDS;
    private static final int ONE_DAY_MINUTES = 1440;

    private static final int SYNC_MANAGER_HEARTBEAT_TIME = 15*MINUTES;
    private static final int CONNECTIVITY_WAIT_TIME = 10*MINUTES;

    // Sync hold constants for services with transient errors
    private static final int HOLD_DELAY_ESCALATION = 30*SECONDS;
    private static final int HOLD_DELAY_MAXIMUM = 3*MINUTES;

    // Reason codes when SyncManager.kick is called (mainly for debugging)
    // UI has changed data, requiring an upsync of changes
    public static final int SYNC_UPSYNC = 0;
    // A scheduled sync (when not using push)
    public static final int SYNC_SCHEDULED = 1;
    // Mailbox was marked push
    public static final int SYNC_PUSH = 2;
    // A ping (EAS push signal) was received
    public static final int SYNC_PING = 3;
    // startSync was requested of SyncManager
    public static final int SYNC_SERVICE_START_SYNC = 4;
    // A part request (attachment load, for now) was sent to SyncManager
    public static final int SYNC_SERVICE_PART_REQUEST = 5;
    // Misc.
    public static final int SYNC_KICK = 6;

    private static final String WHERE_PUSH_OR_PING_NOT_ACCOUNT_MAILBOX =
        MailboxColumns.ACCOUNT_KEY + "=? and " + MailboxColumns.TYPE + "!=" +
        Mailbox.TYPE_EAS_ACCOUNT_MAILBOX + " and " + MailboxColumns.SYNC_INTERVAL +
        " IN (" + Mailbox.CHECK_INTERVAL_PING + ',' + Mailbox.CHECK_INTERVAL_PUSH + ')';
    protected static final String WHERE_IN_ACCOUNT_AND_PUSHABLE =
        MailboxColumns.ACCOUNT_KEY + "=? and type in (" + Mailbox.TYPE_INBOX + ','
        /*+ Mailbox.TYPE_CALENDAR + ','*/ + Mailbox.TYPE_CONTACTS + ')';
    private static final String WHERE_MAILBOX_KEY = EmailContent.RECORD_ID + "=?";
    private static final String WHERE_PROTOCOL_EAS = HostAuthColumns.PROTOCOL + "=\"" +
        AbstractSyncService.EAS_PROTOCOL + "\"";

    // Offsets into the syncStatus data for EAS that indicate type, exit status, and change count
    // The format is S<type_char>:<exit_char>:<change_count>
    public static final int STATUS_TYPE_CHAR = 1;
    public static final int STATUS_EXIT_CHAR = 3;
    public static final int STATUS_CHANGE_COUNT_OFFSET = 5;

    // Ready for ping
    public static final int PING_STATUS_OK = 0;
    // Service already running (can't ping)
    public static final int PING_STATUS_RUNNING = 1;
    // Service waiting after I/O error (can't ping)
    public static final int PING_STATUS_WAITING = 2;
    // Service had a fatal error; can't run
    public static final int PING_STATUS_UNABLE = 3;

    // We synchronize on this for all actions affecting the service and error maps
    private static Object sSyncToken = new Object();
    // All threads can use this lock to wait for connectivity
    public static Object sConnectivityLock = new Object();

    // Keeps track of running services (by mailbox id)
    private HashMap<Long, AbstractSyncService> mServiceMap =
        new HashMap<Long, AbstractSyncService>();
    // Keeps track of services whose last sync ended with an error (by mailbox id)
    private HashMap<Long, SyncError> mSyncErrorMap = new HashMap<Long, SyncError>();
    // Keeps track of which services require a wake lock (by mailbox id)
    private HashMap<Long, Boolean> mWakeLocks = new HashMap<Long, Boolean>();
    // Keeps track of PendingIntents for mailbox alarms (by mailbox id)
    static private HashMap<Long, PendingIntent> sPendingIntents =
        new HashMap<Long, PendingIntent>();
    // The actual WakeLock obtained by SyncManager
    private WakeLock mWakeLock = null;

    // Observers that we use to look for changed mail-related data
    private AccountObserver mAccountObserver;
    private MailboxObserver mMailboxObserver;
    private SyncedMessageObserver mSyncedMessageObserver;
    private MessageObserver mMessageObserver;
    private Handler mHandler = new Handler();

    private ContentResolver mResolver;

    // The singleton SyncManager object, with its thread and stop flag
    protected static SyncManager INSTANCE;
    private static Thread sServiceThread = null;
    private boolean mStop = false;

    // The reason for SyncManager's next wakeup call
    private String mNextWaitReason;

    // Receiver of connectivity broadcasts
    private ConnectivityReceiver mConnectivityReceiver = null;

    // Cached unique device id
    private String mDeviceId = null;

    // The callback sent in from the UI using setCallback
    private IEmailServiceCallback mCallback;
    private RemoteCallbackList<IEmailServiceCallback> mCallbackList =
        new RemoteCallbackList<IEmailServiceCallback>();

    /**
     * Proxy that can be used by various sync adapters to tie into SyncManager's callback system.
     * Used this way:  SyncManager.callback().callbackMethod(args...);
     * The proxy wraps checking for existence of a SyncManager instance and an active callback.
     * Failures of these callbacks can be safely ignored.
     */
    static private final IEmailServiceCallback.Stub sCallbackProxy =
        new IEmailServiceCallback.Stub() {

        public void loadAttachmentStatus(long messageId, long attachmentId, int statusCode,
                int progress) throws RemoteException {
            IEmailServiceCallback cb = INSTANCE == null ? null: INSTANCE.mCallback;
            if (cb != null) {
                cb.loadAttachmentStatus(messageId, attachmentId, statusCode, progress);
            }
        }

        public void sendMessageStatus(long messageId, String subject, int statusCode, int progress)
                throws RemoteException {
            IEmailServiceCallback cb = INSTANCE == null ? null: INSTANCE.mCallback;
            if (cb != null) {
                cb.sendMessageStatus(messageId, subject, statusCode, progress);
            }
        }

        public void syncMailboxListStatus(long accountId, int statusCode, int progress)
                throws RemoteException {
            IEmailServiceCallback cb = INSTANCE == null ? null: INSTANCE.mCallback;
            if (cb != null) {
                cb.syncMailboxListStatus(accountId, statusCode, progress);
            }
        }

        public void syncMailboxStatus(long mailboxId, int statusCode, int progress)
                throws RemoteException {
            IEmailServiceCallback cb = INSTANCE == null ? null: INSTANCE.mCallback;
            if (cb != null) {
                cb.syncMailboxStatus(mailboxId, statusCode, progress);
            } else if (INSTANCE != null) {
                INSTANCE.log("orphan syncMailboxStatus, id=" + mailboxId + " status=" + statusCode);
            }
        }
    };

    /**
     * Create our EmailService implementation here.
     */
    private final IEmailService.Stub mBinder = new IEmailService.Stub() {

        public int validate(String protocol, String host, String userName, String password,
                int port, boolean ssl) throws RemoteException {
            try {
                AbstractSyncService.validate(EasSyncService.class, host, userName, password, port,
                        ssl, SyncManager.this);
                return MessagingException.NO_ERROR;
            } catch (MessagingException e) {
                return e.getExceptionType();
            }
        }

        public void startSync(long mailboxId) throws RemoteException {
            if (INSTANCE == null) return;
            Mailbox m = Mailbox.restoreMailboxWithId(INSTANCE, mailboxId);
            if (m.mType == Mailbox.TYPE_OUTBOX) {
                // We're using SERVER_ID to indicate an error condition (it has no other use for
                // sent mail)  Upon request to sync the Outbox, we clear this so that all messages
                // are candidates for sending.
                ContentValues cv = new ContentValues();
                cv.put(SyncColumns.SERVER_ID, 0);
                INSTANCE.getContentResolver().update(Message.CONTENT_URI,
                    cv, WHERE_MAILBOX_KEY, new String[] {Long.toString(mailboxId)});

                kick("start outbox");
            }
            startManualSync(mailboxId, SyncManager.SYNC_SERVICE_START_SYNC, null);
        }

        public void stopSync(long mailboxId) throws RemoteException {
            stopManualSync(mailboxId);
        }

        public void loadAttachment(long attachmentId, String destinationFile,
                String contentUriString) throws RemoteException {
            Attachment att = Attachment.restoreAttachmentWithId(SyncManager.this, attachmentId);
            partRequest(new PartRequest(att, destinationFile, contentUriString));
        }

        public void updateFolderList(long accountId) throws RemoteException {
            reloadFolderList(SyncManager.this, accountId, false);
        }

        public void setLogging(int on) throws RemoteException {
            Eas.setUserDebug(on);
        }

        public void loadMore(long messageId) throws RemoteException {
            // TODO Auto-generated method stub
        }

        // The following three methods are not implemented in this version
        public boolean createFolder(long accountId, String name) throws RemoteException {
            return false;
        }

        public boolean deleteFolder(long accountId, String name) throws RemoteException {
            return false;
        }

        public boolean renameFolder(long accountId, String oldName, String newName)
                throws RemoteException {
            return false;
        }

        public void setCallback(IEmailServiceCallback cb) throws RemoteException {
            if (mCallback != null) {
                mCallbackList.unregister(mCallback);
            }
            mCallback = cb;
            mCallbackList.register(cb);
        }
    };

    class AccountList extends ArrayList<Account> {
        private static final long serialVersionUID = 1L;

        public boolean contains(long id) {
            for (Account account: this) {
                if (account.mId == id) {
                    return true;
                }
            }
            return false;
        }
    }

    class AccountObserver extends ContentObserver {
        // mAccounts keeps track of Accounts that we care about (EAS for now)
        AccountList mAccounts = new AccountList();

        public AccountObserver(Handler handler) {
            super(handler);
            Context context = getContext();

            // At startup, we want to see what EAS accounts exist and cache them
            Cursor c = getContentResolver().query(Account.CONTENT_URI, Account.CONTENT_PROJECTION,
                    null, null, null);
            try {
                collectEasAccounts(c, mAccounts);
            } finally {
                c.close();
            }

            // Create the account mailbox for any account that doesn't have one
            for (Account account: mAccounts) {
                int cnt = Mailbox.count(context, Mailbox.CONTENT_URI, "accountKey=" + account.mId,
                        null);
                if (cnt == 0) {
                    addAccountMailbox(account.mId);
                }
            }
        }

        private boolean syncParametersChanged(Account account) {
            long accountId = account.mId;
            // Reload account from database to get its current state
            account = Account.restoreAccountWithId(getContext(), accountId);
            for (Account oldAccount: mAccounts) {
                if (oldAccount.mId == accountId) {
                    return oldAccount.mSyncInterval != account.mSyncInterval ||
                            oldAccount.mSyncLookback != account.mSyncLookback;
                }
            }
            // Really, we can't get here, but we don't want the compiler to complain
            return false;
        }

        @Override
        public void onChange(boolean selfChange) {
            maybeStartSyncManagerThread();

            // A change to the list requires us to scan for deletions (to stop running syncs)
            // At startup, we want to see what accounts exist and cache them
            AccountList currentAccounts = new AccountList();
            Cursor c = getContentResolver().query(Account.CONTENT_URI, Account.CONTENT_PROJECTION,
                    null, null, null);
            try {
                collectEasAccounts(c, currentAccounts);
                for (Account account : mAccounts) {
                    if (!currentAccounts.contains(account.mId)) {
                        // This is a deletion; shut down any account-related syncs
                        stopAccountSyncs(account.mId, true);
                        // Delete this from AccountManager...
                        android.accounts.Account acct =
                            new android.accounts.Account(Eas.ACCOUNT_MANAGER_TYPE,
                                    account.mEmailAddress);
                        AccountManager.get(SyncManager.this).removeAccount(acct, null, null);
                    } else {
                        // See whether any of our accounts has changed sync interval or window
                        if (syncParametersChanged(account)) {
                            // Here's one that has...
                            INSTANCE.log("Account " + account.mDisplayName +
                                    " changed; stopping running syncs...");
                            // If account is push, set contacts and inbox to push
                            Account updatedAccount =
                                Account.restoreAccountWithId(getContext(), account.mId);
                            if (updatedAccount.mSyncInterval == Account.CHECK_INTERVAL_PUSH) {
                                ContentValues cv = new ContentValues();
                                cv.put(MailboxColumns.SYNC_INTERVAL, Mailbox.CHECK_INTERVAL_PUSH);
                                getContext().getContentResolver().update(Mailbox.CONTENT_URI, cv,
                                        WHERE_IN_ACCOUNT_AND_PUSHABLE,
                                        new String[] {Long.toString(account.mId)});
                            }
                            // Stop all current syncs; the appropriate ones will restart
                            stopAccountSyncs(account.mId, true);
                        }
                    }
                }

                // Look for new accounts
                for (Account account: currentAccounts) {
                    if (!mAccounts.contains(account.mId)) {
                        // This is an addition; create our magic hidden mailbox...
                        addAccountMailbox(account.mId);
                        mAccounts.add(account);
                    }
                }

                // Finally, make sure mAccounts is up to date
                mAccounts = currentAccounts;
            } finally {
                c.close();
            }

            // See if there's anything to do...
            kick("account changed");
        }

        private void collectEasAccounts(Cursor c, ArrayList<Account> accounts) {
            Context context = getContext();
            while (c.moveToNext()) {
                long hostAuthId = c.getLong(Account.CONTENT_HOST_AUTH_KEY_RECV_COLUMN);
                if (hostAuthId > 0) {
                    HostAuth ha = HostAuth.restoreHostAuthWithId(context, hostAuthId);
                    if (ha != null && ha.mProtocol.equals("eas")) {
                        accounts.add(new Account().restore(c));
                    }
                }
            }
        }

        private void addAccountMailbox(long acctId) {
            Account acct = Account.restoreAccountWithId(getContext(), acctId);
            Mailbox main = new Mailbox();
            main.mDisplayName = Eas.ACCOUNT_MAILBOX;
            main.mServerId = Eas.ACCOUNT_MAILBOX + System.nanoTime();
            main.mAccountKey = acct.mId;
            main.mType = Mailbox.TYPE_EAS_ACCOUNT_MAILBOX;
            main.mSyncInterval = Mailbox.CHECK_INTERVAL_PUSH;
            main.mFlagVisible = false;
            main.save(getContext());
            INSTANCE.log("Initializing account: " + acct.mDisplayName);
        }

        private void stopAccountSyncs(long acctId, boolean includeAccountMailbox) {
            synchronized (sSyncToken) {
                List<Long> deletedBoxes = new ArrayList<Long>();
                for (Long mid : INSTANCE.mServiceMap.keySet()) {
                    Mailbox box = Mailbox.restoreMailboxWithId(INSTANCE, mid);
                    if (box != null) {
                        if (box.mAccountKey == acctId) {
                            if (!includeAccountMailbox &&
                                    box.mType == Mailbox.TYPE_EAS_ACCOUNT_MAILBOX) {
                                AbstractSyncService svc = INSTANCE.mServiceMap.get(mid);
                                if (svc != null) {
                                    svc.stop();
                                }
                                continue;
                            }
                            AbstractSyncService svc = INSTANCE.mServiceMap.get(mid);
                            if (svc != null) {
                                svc.stop();
                                svc.mThread.interrupt();
                            }
                            deletedBoxes.add(mid);
                        }
                    }
                }
                for (Long mid : deletedBoxes) {
                    releaseMailbox(mid);
                }
            }
        }
    }

    class MailboxObserver extends ContentObserver {
        public MailboxObserver(Handler handler) {
            super(handler);
        }

        @Override
        public void onChange(boolean selfChange) {
            // See if there's anything to do...
            if (!selfChange) {
                kick("mailbox changed");
            }
        }
    }

    class SyncedMessageObserver extends ContentObserver {
        long maxChangedId = 0;
        long maxDeletedId = 0;
        Intent syncAlarmIntent = new Intent(INSTANCE, EmailSyncAlarmReceiver.class);
        PendingIntent syncAlarmPendingIntent =
            PendingIntent.getBroadcast(INSTANCE, 0, syncAlarmIntent, 0);
        AlarmManager alarmManager = (AlarmManager)INSTANCE.getSystemService(Context.ALARM_SERVICE);
        final String[] MAILBOX_DATA_PROJECTION = {MessageColumns.MAILBOX_KEY, SyncColumns.DATA};

        public SyncedMessageObserver(Handler handler) {
            super(handler);
        }

        @Override
        public void onChange(boolean selfChange) {
            INSTANCE.log("SyncedMessage changed: (re)setting alarm for 10s");
            alarmManager.set(AlarmManager.RTC_WAKEUP,
                    System.currentTimeMillis() + 10*SECONDS, syncAlarmPendingIntent);
        }
    }

    class MessageObserver extends ContentObserver {

        public MessageObserver(Handler handler) {
            super(handler);
        }

        @Override
        public void onChange(boolean selfChange) {
            // A rather blunt instrument here.  But we don't have information about the URI that
            // triggered this, though it must have been an insert
            if (!selfChange) {
                kick(null);
            }
        }
    }

    static public IEmailServiceCallback callback() {
        return sCallbackProxy;
    }

    static public AccountList getAccountList() {
        if (INSTANCE != null) {
            return INSTANCE.mAccountObserver.mAccounts;
        } else {
            return null;
        }
    }

    public class SyncStatus {
        static public final int NOT_RUNNING = 0;
        static public final int DIED = 1;
        static public final int SYNC = 2;
        static public final int IDLE = 3;
    }

    class SyncError {
        int reason;
        boolean fatal = false;
        long holdEndTime;
        long holdDelay = 0;

        SyncError(int _reason, boolean _fatal) {
            reason = _reason;
            fatal = _fatal;
            escalate();
        }

        /**
         * We increase the hold on I/O errors in 30 second increments to 5 minutes
         */
        void escalate() {
            if (holdDelay < HOLD_DELAY_MAXIMUM) {
                holdDelay += HOLD_DELAY_ESCALATION;
            }
            holdEndTime = System.currentTimeMillis() + holdDelay;
        }
    }

    static public void smLog(String str) {
        if (INSTANCE != null) {
            INSTANCE.log(str);
        }
    }

    protected void log(String str) {
        if (Eas.USER_LOG) {
            Log.d(TAG, str);
            if (Eas.FILE_LOG) {
                FileLogger.log(TAG, str);
            }
        }
    }

    /**
     * EAS requires a unique device id, so that sync is possible from a variety of different
     * devices (e.g. the syncKey is specific to a device)  If we're on an emulator or some other
     * device that doesn't provide one, we can create it as droid<n> where <n> is system time.
     * This would work on a real device as well, but it would be better to use the "real" id if
     * it's available
     */
    static public synchronized String getDeviceId() throws IOException {
        if (INSTANCE == null) {
            throw new IOException();
        }
        // If we've already got the id, return it
        if (INSTANCE.mDeviceId != null) {
            return INSTANCE.mDeviceId;
        }

        // Otherwise, we'll read the id file or create one if it's not found
        try {
            File f = INSTANCE.getFileStreamPath("deviceName");
            BufferedReader rdr = null;
            String id;
            if (f.exists() && f.canRead()) {
                rdr = new BufferedReader(new FileReader(f), 128);
                id = rdr.readLine();
                rdr.close();
                return id;
            } else if (f.createNewFile()) {
                BufferedWriter w = new BufferedWriter(new FileWriter(f), 128);
                id = "droid" + System.currentTimeMillis();
                w.write(id);
                w.close();
                return id;
            }
        } catch (FileNotFoundException e) {
            // We'll just use the default below
            Log.e(TAG, "Can't get device name!");
        } catch (IOException e) {
            // We'll just use the default below
            Log.e(TAG, "Can't get device name!");
        }
        throw new IOException();
    }

    @Override
    public IBinder onBind(Intent arg0) {
        return mBinder;
    }

    @Override
    public void onCreate() {
        if (INSTANCE != null) {
            Log.d(TAG, "onCreate called on running SyncManager");
        } else {
            INSTANCE = this;
            mAccountObserver = new AccountObserver(mHandler);
            mMailboxObserver = new MailboxObserver(mHandler);
            mSyncedMessageObserver = new SyncedMessageObserver(mHandler);
            mMessageObserver = new MessageObserver(mHandler);

            try {
                mDeviceId = getDeviceId();
            } catch (IOException e) {
                // We can't run in this situation
                throw new RuntimeException();
            }
        }

        mResolver = getContentResolver();
        mResolver.registerContentObserver(Account.CONTENT_URI, false, mAccountObserver);

        maybeStartSyncManagerThread();
    }

    @Override
    public void onDestroy() {
        log("!!! SyncManager onDestroy");

        // Cover the case in which we never really started (no EAS accounts)
        if (INSTANCE == null) {
            return;
        }

        stopServices();
        // Stop receivers and content observers
        if (mConnectivityReceiver != null) {
            unregisterReceiver(mConnectivityReceiver);
        }
        ContentResolver resolver = getContentResolver();
        resolver.unregisterContentObserver(mAccountObserver);
        resolver.unregisterContentObserver(mMailboxObserver);
        resolver.unregisterContentObserver(mSyncedMessageObserver);
        resolver.unregisterContentObserver(mMessageObserver);

        // Clear pending alarms
        clearAlarms();

        // Release our wake lock, if we have one
        synchronized (mWakeLocks) {
            if (mWakeLock != null) {
                mWakeLock.release();
                mWakeLock = null;
            }
        }

        sPendingIntents.clear();

        INSTANCE = null;
    }

    void maybeStartSyncManagerThread() {
        // Start our thread...
        // See if there are any EAS accounts; otherwise, just go away
        if (EmailContent.count(this, HostAuth.CONTENT_URI, WHERE_PROTOCOL_EAS, null) > 0) {
            if (sServiceThread == null || !sServiceThread.isAlive()) {
                log(sServiceThread == null ? "Starting thread..." : "Restarting thread...");
                sServiceThread = new Thread(this, "SyncManager");
                sServiceThread.start();
            }
        }
    }

    static public void reloadFolderList(Context context, long accountId, boolean force) {
        if (INSTANCE == null) return;
        Cursor c = context.getContentResolver().query(Mailbox.CONTENT_URI,
                Mailbox.CONTENT_PROJECTION, MailboxColumns.ACCOUNT_KEY + "=? AND " +
                MailboxColumns.TYPE + "=?",
                new String[] {Long.toString(accountId),
                    Long.toString(Mailbox.TYPE_EAS_ACCOUNT_MAILBOX)}, null);
        try {
            if (c.moveToFirst()) {
                synchronized(sSyncToken) {
                    Mailbox m = new Mailbox().restore(c);
                    String syncKey = m.mSyncKey;
                    // No need to reload the list if we don't have one
                    if (!force && (syncKey == null || syncKey.equals("0"))) {
                        return;
                    }

                    // Change all ping/push boxes to push/hold
                    ContentValues cv = new ContentValues();
                    cv.put(Mailbox.SYNC_INTERVAL, Mailbox.CHECK_INTERVAL_PUSH_HOLD);
                    context.getContentResolver().update(Mailbox.CONTENT_URI, cv,
                            WHERE_PUSH_OR_PING_NOT_ACCOUNT_MAILBOX,
                            new String[] {Long.toString(accountId)});
                    INSTANCE.log("Set push/ping boxes to push/hold");

                    long id = m.mId;
                    AbstractSyncService svc = INSTANCE.mServiceMap.get(id);
                    // Tell the service we're done
                    if (svc != null) {
                        synchronized (svc.getSynchronizer()) {
                            svc.stop();
                        }
                        // Interrupt the thread so that it can stop
                        Thread thread = svc.mThread;
                        thread.setName(thread.getName() + " (Stopped)");
                        thread.interrupt();
                        // Abandon the service
                        INSTANCE.releaseMailbox(id);
                        // And have it start naturally
                        kick("reload folder list");
                    }
                }
            }
        } finally {
            c.close();
        }
    }

    /**
     * Informs SyncManager that an account has a new folder list; as a result, any existing folder
     * might have become invalid.  Therefore, we act as if the account has been deleted, and then
     * we reinitialize it.
     *
     * @param acctId
     */
    static public void folderListReloaded(long acctId) {
        if (INSTANCE != null) {
            AccountObserver obs = INSTANCE.mAccountObserver;
            obs.stopAccountSyncs(acctId, false);
            kick("reload folder list");
        }
    }

//    private void logLocks(String str) {
//        StringBuilder sb = new StringBuilder(str);
//        boolean first = true;
//        for (long id: mWakeLocks.keySet()) {
//            if (!first) {
//                sb.append(", ");
//            } else {
//                first = false;
//            }
//            sb.append(id);
//        }
//        log(sb.toString());
//    }

    private void acquireWakeLock(long id) {
        synchronized (mWakeLocks) {
            Boolean lock = mWakeLocks.get(id);
            if (lock == null) {
                if (id > 0) {
                    //log("+WakeLock requested for " + alarmOwner(id));
                }
                if (mWakeLock == null) {
                    PowerManager pm = (PowerManager)getSystemService(Context.POWER_SERVICE);
                    mWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "MAIL_SERVICE");
                    mWakeLock.acquire();
                    log("+WAKE LOCK ACQUIRED");
                }
                mWakeLocks.put(id, true);
                //logLocks("Post-acquire of WakeLock for " + alarmOwner(id) + ": ");
            }
        }
    }

    private void releaseWakeLock(long id) {
        synchronized (mWakeLocks) {
            Boolean lock = mWakeLocks.get(id);
            if (lock != null) {
                if (id > 0) {
                    //log("+WakeLock not needed for " + alarmOwner(id));
                }
                mWakeLocks.remove(id);
                if (mWakeLocks.isEmpty()) {
                    if (mWakeLock != null) {
                        mWakeLock.release();
                    }
                    mWakeLock = null;
                    log("+WAKE LOCK RELEASED");
                } else {
                    //logLocks("Post-release of WakeLock for " + alarmOwner(id) + ": ");
                }
            }
        }
    }

    static public String alarmOwner(long id) {
        if (id == SYNC_MANAGER_ID) {
            return "SyncManager";
        } else
            return "Mailbox " + Long.toString(id);
    }

    private void clearAlarm(long id) {
        synchronized (sPendingIntents) {
            PendingIntent pi = sPendingIntents.get(id);
            if (pi != null) {
                AlarmManager alarmManager = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
                alarmManager.cancel(pi);
                //log("+Alarm cleared for " + alarmOwner(id));
                sPendingIntents.remove(id);
            }
        }
    }

    private void setAlarm(long id, long millis) {
        synchronized (sPendingIntents) {
            PendingIntent pi = sPendingIntents.get(id);
            if (pi == null) {
                Intent i = new Intent(this, MailboxAlarmReceiver.class);
                i.putExtra("mailbox", id);
                i.setData(Uri.parse("Box" + id));
                pi = PendingIntent.getBroadcast(this, 0, i, 0);
                sPendingIntents.put(id, pi);

                AlarmManager alarmManager = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
                alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + millis, pi);
                //log("+Alarm set for " + alarmOwner(id) + ", " + millis/1000 + "s");
            }
        }
    }

    private void clearAlarms() {
        AlarmManager alarmManager = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
        synchronized (sPendingIntents) {
            for (PendingIntent pi : sPendingIntents.values()) {
                alarmManager.cancel(pi);
            }
            sPendingIntents.clear();
        }
    }

    static public void runAwake(long id) {
        if (INSTANCE == null) return;
        INSTANCE.acquireWakeLock(id);
        INSTANCE.clearAlarm(id);
    }

    static public void runAsleep(long id, long millis) {
        if (INSTANCE == null) return;
        INSTANCE.setAlarm(id, millis);
        INSTANCE.releaseWakeLock(id);
    }

    static public void ping(long id) {
        if (id < 0) {
            kick("ping SyncManager");
        } else {
            AbstractSyncService service = INSTANCE.mServiceMap.get(id);
            if (service != null) {
                Mailbox m = Mailbox.restoreMailboxWithId(INSTANCE, id);
                if (m != null) {
                    service.mAccount = Account.restoreAccountWithId(INSTANCE, m.mAccountKey);
                    service.mMailbox = m;
                    service.ping();
                }
            }
        }
    }

    private void releaseConnectivityLock(String reason) {
        // Clear our sync error map when we get connected
        mSyncErrorMap.clear();
        synchronized (sConnectivityLock) {
            sConnectivityLock.notifyAll();
        }
        kick(reason);
    }

    public class ConnectivityReceiver extends BroadcastReceiver {
        @Override
        public void onReceive(Context context, Intent intent) {
            Bundle b = intent.getExtras();
            if (b != null) {
                NetworkInfo a = (NetworkInfo)b.get(ConnectivityManager.EXTRA_NETWORK_INFO);
                String info = "Connectivity alert for " + a.getTypeName();
                State state = a.getState();
                if (state == State.CONNECTED) {
                    info += " CONNECTED";
                    log(info);
                    releaseConnectivityLock("connected");
                } else if (state == State.DISCONNECTED) {
                    info += " DISCONNECTED";
                    a = (NetworkInfo)b.get(ConnectivityManager.EXTRA_OTHER_NETWORK_INFO);
                    if (a != null && a.getState() == State.CONNECTED) {
                        info += " (OTHER CONNECTED)";
                        releaseConnectivityLock("disconnect/other");
                        ConnectivityManager cm =
                            (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
                        if (cm != null) {
                            NetworkInfo i = cm.getActiveNetworkInfo();
                            if (i == null || i.getState() != State.CONNECTED) {
                                log("CM says we're connected, but no active info?");
                            }
                        }
                    } else {
                        log(info);
                        kick("disconnected");
                    }
                }
            }
        }
    }

    private void startService(AbstractSyncService service, Mailbox m) {
        synchronized (sSyncToken) {
            String mailboxName = m.mDisplayName;
            String accountName = service.mAccount.mDisplayName;
            Thread thread = new Thread(service, mailboxName + "(" + accountName + ")");
            log("Starting thread for " + mailboxName + " in account " + accountName);
            thread.start();
            mServiceMap.put(m.mId, service);
            runAwake(m.mId);
        }
    }

    private void startService(Mailbox m, int reason, PartRequest req) {
        synchronized (sSyncToken) {
            Account acct = Account.restoreAccountWithId(this, m.mAccountKey);
            if (acct != null) {
                AbstractSyncService service;
                service = new EasSyncService(this, m);
                service.mSyncReason = reason;
                if (req != null) {
                    service.addPartRequest(req);
                }
                startService(service, m);
            }
        }
    }

    private void stopServices() {
        synchronized (sSyncToken) {
            ArrayList<Long> toStop = new ArrayList<Long>();

            // Keep track of which services to stop
            for (Long mailboxId : mServiceMap.keySet()) {
                toStop.add(mailboxId);
            }

            // Shut down all of those running services
            for (Long mailboxId : toStop) {
                AbstractSyncService svc = mServiceMap.get(mailboxId);
                if (svc != null) {
                    log("Stopping " + svc.mAccount.mDisplayName + '/' + svc.mMailbox.mDisplayName);
                    svc.stop();
                    if (svc.mThread != null) {
                        svc.mThread.interrupt();
                    }
                }
                releaseWakeLock(mailboxId);
            }
        }
    }

    private void waitForConnectivity() {
        int cnt = 0;
        while (!mStop) {
            ConnectivityManager cm =
                (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
            NetworkInfo info = cm.getActiveNetworkInfo();
            if (info != null) {
                log("NetworkInfo: " + info.getTypeName() + ", " + info.getState().name());
                return;
            } else {

                // If we're waiting for the long haul, shut down running service threads
                if (++cnt > 1) {
                    stopServices();
                }

                // Wait until a network is connected, but let the device sleep
                // We'll set an alarm just in case we don't get notified (bugs happen)
                synchronized (sConnectivityLock) {
                    runAsleep(SYNC_MANAGER_ID, CONNECTIVITY_WAIT_TIME+5*SECONDS);
                    try {
                        log("Connectivity lock...");
                        sConnectivityLock.wait(CONNECTIVITY_WAIT_TIME);
                        log("Connectivity lock released...");
                    } catch (InterruptedException e) {
                    }
                    runAwake(SYNC_MANAGER_ID);
                }
            }
        }
    }

    public void run() {
        mStop = false;

        // If we're really debugging, turn on all logging
        if (Eas.DEBUG) {
            Eas.USER_LOG = true;
            Eas.PARSER_LOG = true;
            Eas.FILE_LOG = true;
        }

        // If we need to wait for the debugger, do so
        if (Eas.WAIT_DEBUG) {
            Debug.waitForDebugger();
        }

        // Set up our observers; we need them to know when to start/stop various syncs based
        // on the insert/delete/update of mailboxes and accounts
        // We also observe synced messages to trigger upsyncs at the appropriate time
        mResolver.registerContentObserver(Mailbox.CONTENT_URI, false, mMailboxObserver);
        mResolver.registerContentObserver(Message.SYNCED_CONTENT_URI, true, mSyncedMessageObserver);
        mResolver.registerContentObserver(Message.CONTENT_URI, true, mMessageObserver);

        mConnectivityReceiver = new ConnectivityReceiver();
        registerReceiver(mConnectivityReceiver,
                new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION));

        try {
            while (!mStop) {
                runAwake(SYNC_MANAGER_ID);
                waitForConnectivity();
                mNextWaitReason = "Heartbeat";
                long nextWait = checkMailboxes();
                try {
                    synchronized (this) {
                        if (nextWait < 0) {
                            log("Negative wait? Setting to 1s");
                            nextWait = 1*SECONDS;
                        }
                        if (nextWait > 30*SECONDS) {
                            runAsleep(SYNC_MANAGER_ID, nextWait - 1000);
                        }
                        if (nextWait != SYNC_MANAGER_HEARTBEAT_TIME) {
                            log("Next awake in " + nextWait / 1000 + "s: " + mNextWaitReason);
                        }
                        wait(nextWait);
                    }
                } catch (InterruptedException e) {
                    // Needs to be caught, but causes no problem
                }
            }
            stopServices();
            log("Shutdown requested");
        } finally {
            log("Goodbye");
        }

        startService(new Intent(this, SyncManager.class));
        throw new RuntimeException("EAS SyncManager crash; please restart me...");
    }

    private void releaseMailbox(long mailboxId) {
        mServiceMap.remove(mailboxId);
        releaseWakeLock(mailboxId);
    }

    private long checkMailboxes () {
        // First, see if any running mailboxes have been deleted
        ArrayList<Long> deletedMailboxes = new ArrayList<Long>();
        synchronized (sSyncToken) {
            for (long mailboxId: mServiceMap.keySet()) {
                Mailbox m = Mailbox.restoreMailboxWithId(this, mailboxId);
                if (m == null) {
                    deletedMailboxes.add(mailboxId);
                }
            }
        }
        // If so, stop them or remove them from the map
        for (Long mailboxId: deletedMailboxes) {
            AbstractSyncService svc = mServiceMap.get(mailboxId);
            if (svc != null) {
                boolean alive = svc.mThread.isAlive();
                log("Deleted mailbox: " + svc.mMailboxName);
                if (alive) {
                    stopManualSync(mailboxId);
                } else {
                    log("Removing from serviceMap");
                    releaseMailbox(mailboxId);
                }
            }
        }

        long nextWait = SYNC_MANAGER_HEARTBEAT_TIME;
        long now = System.currentTimeMillis();
        // Start up threads that need it...
        Cursor c = getContentResolver().query(Mailbox.CONTENT_URI,
                Mailbox.CONTENT_PROJECTION, null, null, null);
        try {
            while (c.moveToNext()) {
                // TODO Could be much faster - just get cursor of
                // ones we're watching...
                long aid = c.getLong(Mailbox.CONTENT_ACCOUNT_KEY_COLUMN);
                // Only check mailboxes for EAS accounts
                if (!mAccountObserver.mAccounts.contains(aid)) {
                    continue;
                }
                long mid = c.getLong(Mailbox.CONTENT_ID_COLUMN);
                AbstractSyncService service = mServiceMap.get(mid);
                if (service == null) {
                    // Check whether we're in a hold (temporary or permanent)
                    SyncError syncError = mSyncErrorMap.get(mid);
                    if (syncError != null) {
                        // Nothing we can do about fatal errors
                        if (syncError.fatal) continue;
                        if (now < syncError.holdEndTime) {
                            // If release time is earlier than next wait time,
                            // move next wait time up to the release time
                            if (syncError.holdEndTime < now + nextWait) {
                                nextWait = syncError.holdEndTime - now;
                                mNextWaitReason = "Release hold";
                            }
                            continue;
                        } else {
                            // The hold has ended; remove from the error map
                            mSyncErrorMap.remove(mid);
                        }
                    }
                    long freq = c.getInt(Mailbox.CONTENT_SYNC_INTERVAL_COLUMN);
                    if (freq == Mailbox.CHECK_INTERVAL_PUSH) {
                        Mailbox m = EmailContent.getContent(c, Mailbox.class);
                        startService(m, SYNC_PUSH, null);
                    } else if (c.getInt(Mailbox.CONTENT_TYPE_COLUMN) == Mailbox.TYPE_OUTBOX) {
                        int cnt = EmailContent.count(this, Message.CONTENT_URI,
                                EasOutboxService.MAILBOX_KEY_AND_NOT_SEND_FAILED,
                                new String[] {Long.toString(mid)});
                        if (cnt > 0) {
                            Mailbox m = EmailContent.getContent(c, Mailbox.class);
                            startService(new EasOutboxService(this, m), m);
                        }
                    } else if (freq > 0 && freq <= ONE_DAY_MINUTES) {
                        long lastSync = c.getLong(Mailbox.CONTENT_SYNC_TIME_COLUMN);
                        long toNextSync = freq*MINUTES - (now - lastSync);
                        if (toNextSync <= 0) {
                            Mailbox m = EmailContent.getContent(c, Mailbox.class);
                            startService(m, SYNC_SCHEDULED, null);
                        } else if (toNextSync < nextWait) {
                            nextWait = toNextSync;
                            mNextWaitReason = "Scheduled sync, "
                                + c.getString(Mailbox.CONTENT_DISPLAY_NAME_COLUMN);
                        }
                    }
                } else {
                    Thread thread = service.mThread;
                    if (thread != null && !thread.isAlive()) {
                        releaseMailbox(mid);
                        // Restart this if necessary
                        if (nextWait > 3*SECONDS) {
                            nextWait = 3*SECONDS;
                            mNextWaitReason = "Clean up dead thread(s)";
                        }
                    } else {
                        long requestTime = service.mRequestTime;
                        if (requestTime > 0) {
                            long timeToRequest = requestTime - now;
                            if (service instanceof AbstractSyncService && timeToRequest <= 0) {
                                service.mRequestTime = 0;
                                service.ping();
                            } else if (requestTime > 0 && timeToRequest < nextWait) {
                                if (timeToRequest < 11*MINUTES) {
                                    nextWait = timeToRequest < 250 ? 250 : timeToRequest;
                                    mNextWaitReason = "Sync data change";
                                } else {
                                    log("Illegal timeToRequest: " + timeToRequest);
                                }
                            }
                        }
                    }
                }
            }
        } finally {
            c.close();
        }
        return nextWait;
    }

    static public void serviceRequest(long mailboxId, int reason) {
        serviceRequest(mailboxId, 5*SECONDS, reason);
    }

    static public void serviceRequest(long mailboxId, long ms, int reason) {
        if (INSTANCE == null) return;
        try {
            AbstractSyncService service = INSTANCE.mServiceMap.get(mailboxId);
            if (service != null) {
                service.mRequestTime = System.currentTimeMillis() + ms;
                kick("service request");
            } else {
                startManualSync(mailboxId, reason, null);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    static public void serviceRequestImmediate(long mailboxId) {
        if (INSTANCE == null) return;
        AbstractSyncService service = INSTANCE.mServiceMap.get(mailboxId);
        if (service != null) {
            service.mRequestTime = System.currentTimeMillis();
            Mailbox m = Mailbox.restoreMailboxWithId(INSTANCE, mailboxId);
            if (m != null) {
                service.mAccount = Account.restoreAccountWithId(INSTANCE, m.mAccountKey);
                service.mMailbox = m;
                kick("service request immediate");
            }
        }
    }

    static public void partRequest(PartRequest req) {
        if (INSTANCE == null) return;
        Message msg = Message.restoreMessageWithId(INSTANCE, req.emailId);
        if (msg == null) {
            return;
        }
        long mailboxId = msg.mMailboxKey;
        AbstractSyncService service = INSTANCE.mServiceMap.get(mailboxId);

        if (service == null) {
            service = startManualSync(mailboxId, SYNC_SERVICE_PART_REQUEST, req);
            kick("part request");
        } else {
            service.addPartRequest(req);
        }
    }

    static public PartRequest hasPartRequest(long emailId, String part) {
        if (INSTANCE == null) return null;
        Message msg = Message.restoreMessageWithId(INSTANCE, emailId);
        if (msg == null) {
            return null;
        }
        long mailboxId = msg.mMailboxKey;
        AbstractSyncService service = INSTANCE.mServiceMap.get(mailboxId);
        if (service != null) {
            return service.hasPartRequest(emailId, part);
        }
        return null;
    }

    static public void cancelPartRequest(long emailId, String part) {
        Message msg = Message.restoreMessageWithId(INSTANCE, emailId);
        if (msg == null) {
            return;
        }
        long mailboxId = msg.mMailboxKey;
        AbstractSyncService service = INSTANCE.mServiceMap.get(mailboxId);
        if (service != null) {
            service.cancelPartRequest(emailId, part);
        }
    }

    /**
     * Determine whether a given Mailbox can be synced, i.e. is not already syncing and is not in
     * an error state
     *
     * @param mailboxId
     * @return whether or not the Mailbox is available for syncing (i.e. is a valid push target)
     */
    static public int pingStatus(long mailboxId) {
        // Already syncing...
        if (INSTANCE.mServiceMap.get(mailboxId) != null) {
            return PING_STATUS_RUNNING;
        }
        // No errors or a transient error, don't ping...
        SyncError error = INSTANCE.mSyncErrorMap.get(mailboxId);
        if (error != null) {
            if (error.fatal) {
                return PING_STATUS_UNABLE;
            } else {
                return PING_STATUS_WAITING;
            }
        }
        return PING_STATUS_OK;
    }

    static public AbstractSyncService startManualSync(long mailboxId, int reason, PartRequest req) {
        if (INSTANCE == null || INSTANCE.mServiceMap == null) return null;
        synchronized (sSyncToken) {
            if (INSTANCE.mServiceMap.get(mailboxId) == null) {
                INSTANCE.mSyncErrorMap.remove(mailboxId);
                Mailbox m = Mailbox.restoreMailboxWithId(INSTANCE, mailboxId);
                INSTANCE.log("Starting sync for " + m.mDisplayName);
                INSTANCE.startService(m, reason, req);
            }
        }
        return INSTANCE.mServiceMap.get(mailboxId);
    }

    // DO NOT CALL THIS IN A LOOP ON THE SERVICEMAP
    static private void stopManualSync(long mailboxId) {
        if (INSTANCE == null || INSTANCE.mServiceMap == null) return;
        synchronized (sSyncToken) {
            AbstractSyncService svc = INSTANCE.mServiceMap.get(mailboxId);
            if (svc != null) {
                INSTANCE.log("Stopping sync for " + svc.mMailboxName);
                svc.stop();
                svc.mThread.interrupt();
                INSTANCE.releaseWakeLock(mailboxId);
            }
        }
    }

    /**
     * Wake up SyncManager to check for mailboxes needing service
     */
    static public void kick(String reason) {
        if (INSTANCE != null) {
            synchronized (INSTANCE) {
                INSTANCE.notify();
            }
        }
        if (sConnectivityLock != null) {
            synchronized (sConnectivityLock) {
                sConnectivityLock.notify();
            }
        }
    }

    static public void kick(long mailboxId) {
        if (INSTANCE == null) return;
        Mailbox m = Mailbox.restoreMailboxWithId(INSTANCE, mailboxId);
        int syncType = m.mSyncInterval;
        if (syncType == Mailbox.CHECK_INTERVAL_PUSH) {
            SyncManager.serviceRequestImmediate(mailboxId);
        } else {
            SyncManager.startManualSync(mailboxId, SYNC_KICK, null);
        }
    }

    static public void accountUpdated(long acctId) {
        if (INSTANCE == null) return;
        synchronized (sSyncToken) {
            for (AbstractSyncService svc : INSTANCE.mServiceMap.values()) {
                if (svc.mAccount.mId == acctId) {
                    svc.mAccount = Account.restoreAccountWithId(INSTANCE, acctId);
                }
            }
        }
    }

    /**
     * Sent by services indicating that their thread is finished; action depends on the exitStatus
     * of the service.
     *
     * @param svc the service that is finished
     */
    static public void done(AbstractSyncService svc) {
        if (INSTANCE == null) return;
        synchronized(sSyncToken) {
            long mailboxId = svc.mMailboxId;
            HashMap<Long, SyncError> errorMap = INSTANCE.mSyncErrorMap;
            SyncError syncError = errorMap.get(mailboxId);
            INSTANCE.releaseMailbox(mailboxId);
            int exitStatus = svc.mExitStatus;
            switch (exitStatus) {
                case AbstractSyncService.EXIT_DONE:
                    if (!svc.mPartRequests.isEmpty()) {
                        // TODO Handle this case
                    }
                    errorMap.remove(mailboxId);
                    break;
                case AbstractSyncService.EXIT_IO_ERROR:
                    if (syncError != null) {
                        syncError.escalate();
                        INSTANCE.log("Mailbox " + mailboxId + " now held for "
                                + syncError.holdDelay + "s");
                    } else {
                        errorMap.put(mailboxId, INSTANCE.new SyncError(exitStatus, false));
                        INSTANCE.log("Mailbox " + mailboxId + " added to syncErrorMap");
                    }
                    break;
                case AbstractSyncService.EXIT_LOGIN_FAILURE:
                case AbstractSyncService.EXIT_EXCEPTION:
                    errorMap.put(mailboxId, INSTANCE.new SyncError(exitStatus, true));
                    break;
            }
            kick("sync completed");
        }
    }

    /**
     * Given the status string from a Mailbox, return the type code for the last sync
     * @param status the syncStatus column of a Mailbox
     * @return
     */
    static public int getStatusType(String status) {
        if (status == null) {
            return -1;
        } else {
            return status.charAt(STATUS_TYPE_CHAR) - '0';
        }
    }

    /**
     * Given the status string from a Mailbox, return the change count for the last sync
     * The change count is the number of adds + deletes + changes in the last sync
     * @param status the syncStatus column of a Mailbox
     * @return
     */
    static public int getStatusChangeCount(String status) {
        try {
            String s = status.substring(STATUS_CHANGE_COUNT_OFFSET);
            return Integer.parseInt(s);
        } catch (RuntimeException e) {
            return -1;
        }
    }

    static public Context getContext() {
        return INSTANCE;
    }
}