root/trunk/LogicMail/src/org/logicprobe/LogicMail/model/MailManager.java

/*-
 * Copyright (c) 2008, Derek Konigsberg
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution. 
 * 3. Neither the name of the project nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.logicprobe.LogicMail.model;

import java.util.Vector;

import org.logicprobe.LogicMail.conf.AccountConfig;
import org.logicprobe.LogicMail.conf.MailSettings;
import org.logicprobe.LogicMail.conf.MailSettingsEvent;
import org.logicprobe.LogicMail.conf.MailSettingsListener;
import org.logicprobe.LogicMail.conf.OutgoingConfig;
import org.logicprobe.LogicMail.mail.AbstractMailSender;
import org.logicprobe.LogicMail.mail.MailConnectionListener;
import org.logicprobe.LogicMail.mail.MailConnectionLoginEvent;
import org.logicprobe.LogicMail.mail.MailConnectionManager;
import org.logicprobe.LogicMail.mail.MailConnectionStateEvent;
import org.logicprobe.LogicMail.mail.MailConnectionStatusEvent;
import org.logicprobe.LogicMail.mail.MailFactory;
import org.logicprobe.LogicMail.mail.NetworkMailSender;
import org.logicprobe.LogicMail.mail.NetworkMailStore;
import org.logicprobe.LogicMail.util.EventListenerList;

/**
 * Singleton that provides external access to the mail data model.
 * Ensures that clients have a fully controlled point from which
 * to get their instances of data and utility classes.
 */
public class MailManager {
        private static MailManager instance = null;
        private EventListenerList listenerList = new EventListenerList();
        private MailRootNode mailRootNode;
        private MailSettings mailSettings;
        private OutboxMailboxNode outboxMailboxNode;
        
        /**
         * Constructor.
         */
        private MailManager() {
                mailSettings = MailSettings.getInstance();
                mailRootNode = new MailRootNode();

                // Make sure the initial configuration is loaded
                updateMailModelAccountList();
                
                // Register a listener for configuration changes
                MailSettings.getInstance().addMailSettingsListener(new MailSettingsListener() {
                        public void mailSettingsSaved(MailSettingsEvent e) {
                            mailSettings_MailSettingsSaved(e);
                        }
                });
                
                MailConnectionManager.getInstance().addMailConnectionListener(new MailConnectionListener() {
                        public void mailConnectionStateChanged(MailConnectionStateEvent e) {
                                mailConnectionManager_MailConnectionStateChanged(e);
                        }
                        public void mailConnectionStatus(MailConnectionStatusEvent e) { }
                        public void mailConnectionError(MailConnectionStatusEvent e) { }
                        public void mailConnectionLogin(MailConnectionLoginEvent e) { }
                });
                
                // Refresh data from local account node
                LocalAccountNode localAccount = mailRootNode.getLocalAccount();
                localAccount.refreshMailboxes();
                localAccount.refreshMailboxStatus();

                MailboxNode[] localMailboxes = mailRootNode.getLocalAccount().getRootMailbox().getMailboxes();
                for(int i=0; i<localMailboxes.length; i++) {
                // Find the outbox node, and save a reference to it for easy access
                        if(localMailboxes[i] instanceof OutboxMailboxNode) {
                                outboxMailboxNode = (OutboxMailboxNode)localMailboxes[i];
                        }
                        
                        // Refresh messages for local mailboxes
                        localMailboxes[i].refreshMessages();
                }
        }
        
        private void refreshMailboxTypes() {
                int num = mailSettings.getNumAccounts();
                for(int i=0; i<num; i++) {
                        AccountConfig accountConfig = mailSettings.getAccountConfig(i);
                        MailboxNode mailbox;
                        mailbox = accountConfig.getDraftMailbox();
                        if(mailbox != null) { mailbox.setType(MailboxNode.TYPE_DRAFTS); }
                        mailbox = accountConfig.getSentMailbox();
                        if(mailbox != null) { mailbox.setType(MailboxNode.TYPE_SENT); }
                }
        }
        
        /**
         * First time initialization sequence, should only be invoked on
         * application startup.
         */
        public static void initialize() {
                MailManager mailManager = MailManager.getInstance();
                mailManager.refreshMailboxTypes();
        }
        
        /**
         * Gets the mail manager instance.
         * 
         * @return The instance.
         */
        public static synchronized MailManager getInstance() {
                if(instance == null) {
                        instance = new MailManager();
                }
                return instance;
        }
        
        /**
         * Gets the mail root node.
         * Also performs any necessary initialization on
         * the first call.
         * 
         * @return Mail root node.
         */
        public synchronized MailRootNode getMailRootNode() {
                return mailRootNode;
        }

        /**
         * Gets the outbox node within the local account.
         * 
         * @return Outbox node.
         */
        public OutboxMailboxNode getOutboxMailboxNode() {
                return outboxMailboxNode;
        }

        private void mailSettings_MailSettingsSaved(MailSettingsEvent e) {
        // This logic is rather crude, and will trigger a full refresh
        // under a wide variety of circumstances.  Its major intent is
        // to avoid a refresh in a few situations where a minor
        // configuration change affects future behavior and not
        // current state.
        
        boolean shouldRefreshAccounts =
            connectionListChanged(e) || accountChangeRequiringRefresh(e);
        
        // Trigger a refresh if appropriate
        if(shouldRefreshAccounts) {
            updateMailModelAccountList();
            refreshMailboxTypes();
        }
        }

    private boolean connectionListChanged(MailSettingsEvent e) {
        int listChange = e.getListChange();
        return (listChange & MailSettingsEvent.LIST_CHANGED_ACCOUNT) != 0
                || (listChange & MailSettingsEvent.LIST_CHANGED_OUTGOING) != 0;
    }
        
    private boolean accountChangeRequiringRefresh(MailSettingsEvent e) {
        boolean refreshRequired = false;
        int num = mailSettings.getNumAccounts();
        for(int i=0; i<num; i++) {
            AccountConfig accountConfig = mailSettings.getAccountConfig(i);
            int accountChange = e.getConfigChange(accountConfig);
            if((accountChange & AccountConfig.CHANGE_TYPE_NAME) != 0
                    || (accountChange & AccountConfig.CHANGE_TYPE_MAILBOXES) != 0
                    || (accountChange & AccountConfig.CHANGE_TYPE_OUTGOING) != 0) {
                refreshRequired = true;
                break;
            }
            OutgoingConfig outgoingConfig = accountConfig.getOutgoingConfig();
            if(outgoingConfig != null
                    && (e.getConfigChange(outgoingConfig) & OutgoingConfig.CHANGE_TYPE_CONNECTION) != 0) {
                refreshRequired = true;
                break;
            }
        }
        return refreshRequired;
    }
    
    /**
     * Called when the account configuration has changed,
     * to cause the mail model to update its account list.
     */
    private synchronized void updateMailModelAccountList() {
        // Build the new account list from the configuration and
        // the existing account nodes.  This works by checking to see
        // if an account already exists, and only creating new nodes
        // for new accounts.
        NetworkAccountNode[] existingAccounts = mailRootNode.getNetworkAccounts();
        NetworkAccountNode[] newAccounts = getNewNetworkAccountNodes();

        // Remove and replace all account nodes from the root node.
        // This approach is taken to preserve any ordering which may
        // have been changed in the configuration.
        mailRootNode.removeAccounts(existingAccounts);
        mailRootNode.addAccounts(newAccounts);

        // Clear deleted accounts from the MailFactory and persistent storage
        clearDeletedAccounts(existingAccounts, newAccounts);

        // Get the newly updated account list, and determine whether
        // we need to update any mail senders.
        NetworkAccountNode[] updatedAccounts = mailRootNode.getNetworkAccounts();
        updateAccountMailSenders(updatedAccounts);

        //TODO: Clear deleted senders from the MailFactory

        // Notify any listeners
        fireMailConfigurationChanged();
    }

        private NetworkAccountNode[] getNewNetworkAccountNodes() {
            Vector newAccounts = new Vector();

            int num = mailSettings.getNumAccounts();
            for(int i=0; i<num; i++) {
                AccountConfig accountConfig = mailSettings.getAccountConfig(i);
                NetworkAccountNode existingAccountNode = mailRootNode.findAccountForConfig(accountConfig);

                if(existingAccountNode != null) {
                    newAccounts.addElement(existingAccountNode);
                }
                else {
                    AccountNode newAccountNode = new NetworkAccountNode((NetworkMailStore) MailFactory.createMailStore(accountConfig));
                    newAccountNode.load();
                    newAccounts.addElement(newAccountNode);
                }
            }
            NetworkAccountNode[] newAccountsArray = new NetworkAccountNode[newAccounts.size()];
            newAccounts.copyInto(newAccountsArray);
            return newAccountsArray;
        }
        
    private void clearDeletedAccounts(NetworkAccountNode[] existingAccounts, NetworkAccountNode[] newAccounts) {
        for(int i=0; i<existingAccounts.length; i++) {
            boolean accountDeleted = true;
            for(int j=0; j<newAccounts.length; j++) {
                NetworkAccountNode newAccount = newAccounts[j];
                if(newAccount == existingAccounts[i]) {
                    accountDeleted = false;
                    break;
                }
            }
            if(accountDeleted) {
                existingAccounts[i].removeSavedData();
                MailFactory.clearMailStore(existingAccounts[i].getAccountConfig());
            }
        }
    }

    private void updateAccountMailSenders(NetworkAccountNode[] updatedAccounts) {
        for(int i=0; i<updatedAccounts.length; i++) {
            NetworkAccountNode networkAccount = updatedAccounts[i];
            AbstractMailSender mailSender = networkAccount.getMailSender();
            OutgoingConfig outgoingConfig = networkAccount.getAccountConfig().getOutgoingConfig();
            if(outgoingConfig == null) {
                if(mailSender != null) {
                    mailSender.shutdown(false);
                }
                networkAccount.setMailSender(null);
            }
            else if((mailSender instanceof NetworkMailSender
                    &&((NetworkMailSender)mailSender).getOutgoingConfig() != outgoingConfig)) {
                mailSender.shutdown(false);
                networkAccount.setMailSender(MailFactory.createMailSender(networkAccount.getAccountConfig().getOutgoingConfig()));
            }
            else if(mailSender == null) {
                networkAccount.setMailSender(MailFactory.createMailSender(networkAccount.getAccountConfig().getOutgoingConfig()));
            }
        }
    }

        /**
         * Handle connection state changes by updating the
         * appropriate account nodes.
         * 
         * @param e Event data.
         */
        private void mailConnectionManager_MailConnectionStateChanged(MailConnectionStateEvent e) {
                // Find the account node associated with this event
                AccountNode matchingAccount = mailRootNode.findAccountForConfig(
                        (AccountConfig)e.getConnectionConfig());
                
                // Update account state
                if(matchingAccount != null) {
                        int state = e.getState();
                        if(state == MailConnectionStateEvent.STATE_CONNECTED) {
                                matchingAccount.setStatus(AccountNode.STATUS_ONLINE);
                        }
                        else if(state == MailConnectionStateEvent.STATE_DISCONNECTED) {
                                matchingAccount.setStatus(AccountNode.STATUS_OFFLINE);
                        }
                }
        }
        
        /**
     * Adds a <tt>MailManagerListener</tt> to the mail manager.
     * 
     * @param l The <tt>MailManagerListener</tt> to be added.
     */
    public void addMailManagerListener(MailManagerListener l) {
        listenerList.add(MailManagerListener.class, l);
    }

    /**
     * Removes a <tt>MailManagerListener</tt> from the mail manager.
     * 
     * @param l The <tt>MailManagerListener</tt> to be removed.
     */
    public void removeMailManagerListener(MailManagerListener l) {
        listenerList.remove(MailManagerListener.class, l);
    }
    
    /**
     * Returns an array of all <tt>MailManagerListener</tt>s
     * that have been added to this mail manager.
     * 
     * @return All the <tt>MailManagerListener</tt>s that have been added,
     * or an empty array if no listeners have been added.
     */
    public MailManagerListener[] getMailManagerListeners() {
        return (MailManagerListener[])listenerList.getListeners(MailManagerListener.class);
    }
    
    /**
     * Notifies all registered <tt>MailManagerListener</tt>s that
     * the mail system configuration has changed.
     */
    private void fireMailConfigurationChanged() {
        Object[] listeners = listenerList.getListeners(MailManagerListener.class);
        MailManagerEvent e = null;
        for(int i=0; i<listeners.length; i++) {
            if(e == null) {
                e = new MailManagerEvent(this);
            }
            ((MailManagerListener)listeners[i]).mailConfigurationChanged(e);
        }
    }

}