org/jsampler/CC.java

/*
 *   JSampler - a java front-end for LinuxSampler
 *
 *   Copyright (C) 2005-2011 Grigor Iliev <grigor@grigoriliev.com>
 *
 *   This file is part of JSampler.
 *
 *   JSampler is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License version 2
 *   as published by the Free Software Foundation.
 *
 *   JSampler 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 JSampler; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 *   MA  02111-1307  USA
 */

package org.jsampler;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;

import java.util.Timer;
import java.util.TimerTask;
import java.util.Vector;

import java.util.logging.Handler;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.logging.SimpleFormatter;
import java.util.logging.StreamHandler;

import net.sf.juife.PDUtils;
import net.sf.juife.Task;
import net.sf.juife.TaskQueue;

import net.sf.juife.event.GenericEvent;
import net.sf.juife.event.GenericListener;
import net.sf.juife.event.TaskEvent;
import net.sf.juife.event.TaskListener;
import net.sf.juife.event.TaskQueueEvent;
import net.sf.juife.event.TaskQueueListener;

import org.jsampler.event.ListEvent;
import org.jsampler.event.ListListener;
import org.jsampler.event.OrchestraEvent;
import org.jsampler.event.OrchestraListener;

import org.jsampler.task.*;

import org.jsampler.view.JSChannelsPane;
import org.jsampler.view.JSMainFrame;
import org.jsampler.view.JSProgress;
import org.jsampler.view.JSViewConfig;

import org.linuxsampler.lscp.Client;
import org.linuxsampler.lscp.FxSend;

import org.linuxsampler.lscp.event.*;

import org.w3c.dom.Document;
import org.w3c.dom.Node;

import static org.jsampler.JSI18n.i18n;


/**
 * This class serves as a 'Control Center' of the application.
 * It also provides some fundamental routines and access to most used objects.
 * @author Grigor Iliev
 */
public class CC {
        private static Handler handler;
        private static FileOutputStream fos;
        
        private static JSViewConfig viewConfig = null;
        private static JSMainFrame mainFrame = null;
        private static JSProgress progress = null;
        
        private final static Client lsClient = new Client();
        
        private static String jSamplerHome = null;
        
        private final static TaskQueue taskQueue = new TaskQueue();
        private final static Timer timer = new Timer();
        private static TimerTask progressTimerTask = null;
        
        private static int connectionFailureCount = 0;
        
        static class ProgressTimerTask extends TimerTask {
                public void run() {
                        PDUtils.runOnUiThread(new Runnable() { public void run() { run0(); } });
                }
                
                private void
                run0() { CC.getProgressIndicator().start(); }
        }
        
        public static interface Run<A> {
                public void run(A arg);
        }
        
        /** Forbids the instantiation of this class. */
        private
        CC() { }
        
        /**
         * Returns the logger to be used for logging events.
         * @return The logger to be used for logging events.
         */
        public static Logger
        getLogger() {
                return Logger.getLogger (
                        "org.jsampler",
                        "org.jsampler.langprops.LogsBundle"
                );
        }
        
        /**
         * Returns the task queue to be used for scheduling tasks
         * for execution out of the event-dispatching thread.
         * @return The task queue to be used for scheduling tasks
         * for execution out of the event-dispatching thread.
         */
        public static synchronized TaskQueue
        getTaskQueue() { return taskQueue; }
        
        /**
         * Adds the specified task to the task queue. All task in the
         * queue equal to the specified task are removed from the queue.
         */
        public static synchronized void
        scheduleTask(Task t) {
                while(getTaskQueue().removeTask(t)) { }
                
                getTaskQueue().add(t);
        }
        
        /**
         * Adds the specified task to the task queue only if the last
         * task in the queue is not equal to <code>t</code>.
         */
        public static synchronized void
        addTask(Task t) {
                Task[] tasks = getTaskQueue().getPendingTasks();
                if(tasks.length > 0 && tasks[tasks.length - 1].equals(t)) return;
                getTaskQueue().add(t);
        } 
        
        /**
         * Gets the configuration of the current view.
         */
        public static JSViewConfig
        getViewConfig() { return viewConfig; }
        
        public static JSPrefs
        preferences() { return getViewConfig().preferences(); }
        
        /**
         * Sets the configuration of the current view.
         */
        public static void
        setViewConfig(JSViewConfig viewConfig) { CC.viewConfig = viewConfig; }
        
        /**
         * Returns the main window of this application.
         * @return The main window of this application.
         */
        public static JSMainFrame<JSChannelsPane>
        getMainFrame() { return mainFrame; }
        
        /**
         * Sets the main window of this application.
         * @param mainFrame The main window of this application.
         */
        public static void
        setMainFrame(JSMainFrame mainFrame) { CC.mainFrame = mainFrame; }
        
        /**
         * Gets the progress indicator of this application.
         * @return The progress indicator of this application.
         */
        public static JSProgress
        getProgressIndicator() { return progress; }
        
        /**
         * Sets the progress indicator to be used by this application.
         * @param progress The progress indicator to be used by this application.
         */
        public static void
        setProgressIndicator(JSProgress progress) { CC.progress = progress; }
        
        /**
         * Gets the absolute path to the JSampler's home location.
         * @return The absolute path to the JSampler's home location
         * or <code>null</code> if the JSampler's home location is not specified yet.
         */
        public static String
        getJSamplerHome() { return jSamplerHome; }
        
        /**
         * Sets the location of the JSampler's home.
         * @param path The new absolute path to the JSampler's home location.
         */
        public static void
        setJSamplerHome(String path) {
                jSamplerHome = path;
                Prefs.setJSamplerHome(jSamplerHome);
        }
        
        /**
         * This method does the initial preparation of the application.
         */
        protected static void
        initJSampler() {
                fos = null;
                setJSamplerHome(Prefs.getJSamplerHome());
                String s = getJSamplerHome();
                try {
                        if(s != null) {
                                s += File.separator + "jsampler.log";
                                File f = new File(s);
                                if(f.isFile()) HF.createBackup("jsampler.log", "jsampler.log.0");
                                fos = new FileOutputStream(s);
                        }
                } catch(Exception x) { x.printStackTrace(); }
                
                if(fos == null) handler = new StreamHandler(System.out, new SimpleFormatter());
                else handler = new StreamHandler(fos, new SimpleFormatter());
                
                handler.setLevel(Level.FINE);
                getLogger().addHandler(handler);
                getLogger().setLevel(Level.FINE);
                Logger.getLogger("org.linuxsampler.lscp").setLevel(Level.FINE);
                Logger.getLogger("org.linuxsampler.lscp").addHandler(handler);
                
                // Flushing logs on every second
                timer.schedule(new java.util.TimerTask() {
                        public void
                        run() { if(handler != null) handler.flush(); }
                }, 1000, 1000);
                
                getLogger().fine("CC.jsStarted");
                
                getTaskQueue().addTaskQueueListener(getHandler());
                
                getTaskQueue().start();
                
                getClient().removeChannelCountListener(getHandler());
                getClient().addChannelCountListener(getHandler());
                
                getClient().removeChannelInfoListener(getHandler());
                getClient().addChannelInfoListener(getHandler());
                
                getClient().removeFxSendCountListener(getHandler());
                getClient().addFxSendCountListener(getHandler());
                
                getClient().removeFxSendInfoListener(getHandler());
                getClient().addFxSendInfoListener(getHandler());
                
                getClient().removeStreamCountListener(getHandler());
                getClient().addStreamCountListener(getHandler());
                
                getClient().removeVoiceCountListener(getHandler());
                getClient().addVoiceCountListener(getHandler());
                
                getClient().removeTotalStreamCountListener(getHandler());
                getClient().addTotalStreamCountListener(getHandler());
                
                getClient().removeTotalVoiceCountListener(getHandler());
                getClient().addTotalVoiceCountListener(getHandler());
                
                getClient().removeAudioDeviceCountListener(audioDeviceCountListener);
                getClient().addAudioDeviceCountListener(audioDeviceCountListener);
                
                getClient().removeAudioDeviceInfoListener(audioDeviceInfoListener);
                getClient().addAudioDeviceInfoListener(audioDeviceInfoListener);
                
                getClient().removeMidiDeviceCountListener(midiDeviceCountListener);
                getClient().addMidiDeviceCountListener(midiDeviceCountListener);
                
                getClient().removeMidiDeviceInfoListener(midiDeviceInfoListener);
                getClient().addMidiDeviceInfoListener(midiDeviceInfoListener);
                
                getClient().removeMidiInstrumentMapCountListener(midiInstrMapCountListener);
                getClient().addMidiInstrumentMapCountListener(midiInstrMapCountListener);
                
                getClient().removeMidiInstrumentMapInfoListener(midiInstrMapInfoListener);
                getClient().addMidiInstrumentMapInfoListener(midiInstrMapInfoListener);
                
                getClient().removeMidiInstrumentCountListener(getHandler());
                getClient().addMidiInstrumentCountListener(getHandler());
                
                getClient().removeMidiInstrumentInfoListener(getHandler());
                getClient().addMidiInstrumentInfoListener(getHandler());
                
                getClient().removeGlobalInfoListener(getHandler());
                getClient().addGlobalInfoListener(getHandler());
                
                getClient().removeChannelMidiDataListener(getHandler());
                getClient().addChannelMidiDataListener(getHandler());
                
                getClient().removeSendEffectChainCountListener(getHandler());
                getClient().addSendEffectChainCountListener(getHandler());
                
                getClient().removeSendEffectChainInfoListener(getHandler());
                getClient().addSendEffectChainInfoListener(getHandler());
                
                getClient().removeEffectInstanceInfoListener(getHandler());
                getClient().addEffectInstanceInfoListener(getHandler());
                
                CC.addConnectionEstablishedListener(new GenericListener() {
                        public void
                        jobDone(GenericEvent e) {
                                connectionFailureCount = 0;
                        }
                });
        }
        
        private final static OrchestraListModel orchestras = new DefaultOrchestraListModel();
        
        /**
         * Returns a list containing all available orchestras.
         * @return A list containing all available orchestras.
         */
        public static OrchestraListModel
        getOrchestras() { return orchestras; }
        
        private final static ServerList servers = new ServerList();
        
        /** Returns the server list. */
        public static ServerList
        getServerList() { return servers; }
        
        private static ServerListListener serverListListener = new ServerListListener();
        
        private static class ServerListListener implements GenericListener {
                public void
                jobDone(GenericEvent e) { saveServerList(); }
        }
        
        private static final 
        
        LostFilesModel lostFilesModel = new LostFilesModel();
        
        public static LostFilesModel
        getLostFilesModel() { return lostFilesModel; }
        
        /**
         * Loads the orchestras described in <code>&lt;jsampler_home&gt;/orchestras.xml</code>.
         * If file with name <code>orchestras.xml.bkp</code> exist in the JSampler's home
         * directory, this means that the last save has failed. In that case a recovery file
         * <code>orchestras.xml.rec</code> is created and a recovery procedure
         * will be initiated.
         */
        public static void
        loadOrchestras() {
                if(getJSamplerHome() == null) return;
                
                try {
                        String s = getJSamplerHome();
                        
                        File f = new File(s + File.separator + "orchestras.xml.bkp");
                        if(f.isFile()) HF.createBackup("orchestras.xml.bkp", "orchestras.xml.rec");
                        
                        FileInputStream fis;
                        fis = new FileInputStream(s + File.separator + "orchestras.xml");
                        
                        loadOrchestras(fis);
                        fis.close();
                } catch(Exception x) {
                        getLogger().log(Level.INFO, HF.getErrorMessage(x), x);
                }
                
                getOrchestras().addOrchestraListListener(getHandler());
        }
        
        
        private static void
        loadOrchestras(InputStream in) {
                Document doc = DOMUtils.readObject(in);
                
                try { getOrchestras().readObject(doc.getDocumentElement()); }
                catch(Exception x) {
                        getViewConfig().showErrorMessage(x, "Loading orchestras: ");
                        return;
                }
                
                for(int i = 0; i < getOrchestras().getOrchestraCount(); i++) {
                        getOrchestras().getOrchestra(i).addOrchestraListener(getHandler());
                }
        }
        
        private static void
        saveOrchestras() {
                try {
                        String s = getJSamplerHome();
                        if(s == null) return;
                        
                        HF.createBackup("orchestras.xml", "orchestras.xml.bkp");
                        
                        FileOutputStream fos2;
                        fos2 = new FileOutputStream(s + File.separator + "orchestras.xml", false);
                        
                        Document doc = DOMUtils.createEmptyDocument();
                
                        Node node = doc.createElement("temp");
                        doc.appendChild(node);
                        
                        getOrchestras().writeObject(doc, doc.getDocumentElement());
                        
                        doc.replaceChild(node.getFirstChild(), node);
                
                        DOMUtils.writeObject(doc, fos2);
                        
                        fos2.close();
                        
                        HF.deleteFile("orchestras.xml.bkp");
                } catch(Exception x) {
                        getViewConfig().showErrorMessage(x, "Saving orchestras: ");
                        return;
                }
        }
        
        /**
         * Loads the servers' info described in <code>&lt;jsampler_home&gt;/servers.xml</code>.
         * If file with name <code>servers.xml.bkp</code> exist in the JSampler's home
         * directory, this means that the last save has failed. In that case a recovery file
         * <code>servers.xml.rec</code> is created and a recovery procedure
         * will be initiated.
         */
        public static void
        loadServerList() {
                if(getJSamplerHome() == null) return;
                
                try {
                        String s = getJSamplerHome();
                        
                        File f = new File(s + File.separator + "servers.xml.bkp");
                        if(f.isFile()) HF.createBackup("servers.xml.bkp", "servers.xml.rec");
                        
                        FileInputStream fis;
                        fis = new FileInputStream(s + File.separator + "servers.xml");
                        
                        loadServerList(fis);
                        fis.close();
                } catch(Exception x) {
                        getLogger().log(Level.INFO, HF.getErrorMessage(x), x);
                }
                
                getServerList().addChangeListener(serverListListener);
                
                /* We should have at least one server to connect. */
                if(getServerList().getServerCount() == 0) {
                        Server server = new Server();
                        server.setName("127.0.0.1:8888");
                        server.setAddress("127.0.0.1");
                        server.setPort(8888);
                        getServerList().addServer(server);
                }
        }
        
        
        private static void
        loadServerList(InputStream in) {
                Document doc = DOMUtils.readObject(in);
                
                try { getServerList().readObject(doc.getDocumentElement()); }
                catch(Exception x) {
                        getViewConfig().showErrorMessage(x, "Loading server list: ");
                        return;
                }
        }
        
        private static void
        saveServerList() {
                try {
                        String s = getJSamplerHome();
                        if(s == null) return;
                        
                        HF.createBackup("servers.xml", "servers.xml.bkp");
                        
                        FileOutputStream fos2;
                        fos2 = new FileOutputStream(s + File.separator + "servers.xml", false);
                        
                        Document doc = DOMUtils.createEmptyDocument();
                
                        Node node = doc.createElement("temp");
                        doc.appendChild(node);
                        
                        getServerList().writeObject(doc, doc.getDocumentElement());
                        
                        doc.replaceChild(node.getFirstChild(), node);
                
                        DOMUtils.writeObject(doc, fos2);
                        
                        fos2.close();
                        
                        HF.deleteFile("servers.xml.bkp");
                } catch(Exception x) {
                        getViewConfig().showErrorMessage(x, "Saving server list: ");
                        return;
                }
        }
        
        /**
         * The exit point of the application which ensures clean exit with default exit status 0.
         *  @see #cleanExit(int i)
         */
        public static void
        cleanExit() { cleanExit(0); }
        
        /**
         * The exit point of the application which ensures clean exit.
         * @param i The exit status.
         */
        public static void
        cleanExit(int i) {
                getLogger().fine("CC.jsEnded");
                try { getClient().disconnect(); } // FIXME: this might block the EDT
                catch(Exception x) { x.printStackTrace(); }
                if(backendProcess != null) backendProcess.destroy();
                backendProcess = null;
                fireBackendProcessEvent();
                System.exit(i);
        }
        
        /**
         * Gets the <code>Client</code> object that is used to communicate with the backend.
         * @return The <code>Client</code> object that is used to communicate with the backend.
         */
        public static Client
        getClient() { return lsClient; }
        
        private static final Vector<GenericListener> listeners = new Vector<GenericListener>();
        
        /**
         * Registers the specified listener to be notified (outside the UI thread)
         * when reconnecting to LinuxSampler.
         * @param l The <code>ActionListener</code> to register.
         */
        public static void
        addReconnectListener(GenericListener l) { listeners.add(l); }
        
        /**
         * Removes the specified listener.
         * @param l The <code>ActionListener</code> to remove.
         */
        public static void
        removeReconnectListener(GenericListener l) { listeners.remove(l); }
        
        private static void
        fireReconnectEvent() {
                GenericEvent e = new GenericEvent(CC.class);
                for(GenericListener l : listeners) l.jobDone(e);
        }
        
        private static final Vector<GenericListener> ceListeners = new Vector<GenericListener>();
        
        /**
         * Registers the specified listener to be notified (from the UI thread) when
         * jsampler is connected successfully to LinuxSampler.
         * @param l The <code>GenericListener</code> to register.
         */
        public static void
        addConnectionEstablishedListener(GenericListener l) { ceListeners.add(l); }
        
        /**
         * Removes the specified listener.
         * @param l The <code>GenericListener</code> to remove.
         */
        public static void
        removeConnectionEstablishedListener(GenericListener l) { ceListeners.remove(l); }
        
        private static void
        fireConnectionEstablishedEvent() {
                GenericEvent e = new GenericEvent(CC.class);
                for(GenericListener l : ceListeners) l.jobDone(e);
        }
        
        private static final SamplerModel samplerModel = new DefaultSamplerModel();
        
        /**
         * Gets the sampler model.
         * @return The sampler model.
         */
        public static SamplerModel
        getSamplerModel() { return samplerModel; }
        
        /**
         * Connects to LinuxSampler.
         * The connection can be done asynchronously.
         */
        public static void
        connect() { initSamplerModel(); }
        
        /**
         * Reconnects to LinuxSampler.
         */
        public static void
        reconnect() { initSamplerModel(getCurrentServer()); }
        
        private static Server currentServer = null;
        
        /**
         * Gets the server, to which the frontend is going to connect
         * or is already connected.
         */
        public static Server
        getCurrentServer() { return currentServer; }
        
        /**
         * Sets the current server.
         */
        public static void
        setCurrentServer(Server server) {
                if(server == currentServer) return;
                connectionFailureCount = 0;
                currentServer = server;
        }
        
        /**
         * Sets the LSCP client's read timeout.
         * @param timeout The new timeout value (in seconds).
         */
        public static void
        setClientReadTimeout(int timeout) {
                getTaskQueue().add(new Global.SetClientReadTimeout(timeout));
        }
        
        /**
         * This method updates the information about the backend state.
         * The update can be done asynchronously.
         */
        private static void
        initSamplerModel() {
                getMainFrame().getServer(new Run<Server>() {
                        public void
                        run(Server srv) {
                                if(srv == null) return;
                                initSamplerModel(srv);
                        }
                });
        }
        
        /**
         * This method updates the information about the backend state.
         */
        private static void
        initSamplerModel(Server srv) {
                setCurrentServer(srv);
                final SetServerAddress ssa = new SetServerAddress(srv.getAddress(), srv.getPort());
                
                final DefaultSamplerModel model = (DefaultSamplerModel)getSamplerModel();
                
                final Global.GetServerInfo gsi = new Global.GetServerInfo();
                gsi.addTaskListener(new TaskListener() {
                        public void
                        taskPerformed(TaskEvent e) {
                                if(gsi.doneWithErrors()) return;
                                
                                model.setServerInfo(gsi.getResult());
                                
                                if(CC.getViewConfig().getInstrumentsDbSupport()) {
                                        CC.getViewConfig().initInstrumentsDbTreeModel();
                                }
                        }
                });
                
                final Audio.GetDrivers gaod = new Audio.GetDrivers();
                gaod.addTaskListener(new TaskListener() {
                        public void
                        taskPerformed(TaskEvent e) {
                                if(!gaod.doneWithErrors())
                                        model.setAudioOutputDrivers(gaod.getResult());
                        }
                });
                
                final Global.GetEngines ge = new Global.GetEngines();
                ge.addTaskListener(new TaskListener() {
                        public void
                        taskPerformed(TaskEvent e) {
                                if(!ge.doneWithErrors()) model.setEngines(ge.getResult());
                        }
                });
                
                final Midi.GetDrivers gmid = new Midi.GetDrivers();
                gmid.addTaskListener(new TaskListener() {
                        public void
                        taskPerformed(TaskEvent e) {
                                if(!gmid.doneWithErrors())
                                        model.setMidiInputDrivers(gmid.getResult());
                        }
                });
                
                final Global.GetVolume gv = new Global.GetVolume();
                gv.addTaskListener(new TaskListener() {
                        public void
                        taskPerformed(TaskEvent e) {
                                if(!gv.doneWithErrors())
                                        model.setVolume(gv.getResult());
                        }
                });
                
                final Midi.GetInstrumentMaps mgim = new Midi.GetInstrumentMaps();
                mgim.addTaskListener(new TaskListener() {
                        public void
                        taskPerformed(TaskEvent e) {
                                if(mgim.doneWithErrors()) return;
                                model.removeAllMidiInstrumentMaps();
                                
                                for(MidiInstrumentMap map : mgim.getResult()) {
                                        model.addMidiInstrumentMap(map);
                                }
                        }
                });
                
                final Global.GetEffects gfx = new Global.GetEffects();
                gfx.addTaskListener(new TaskListener() {
                        public void
                        taskPerformed(TaskEvent e) {
                                if(!gfx.doneWithErrors()) model.getEffects().setEffects(gfx.getResult());
                        }
                });
                
                final UpdateChannels uc = new UpdateChannels();
                uc.addTaskListener(new TaskListener() {
                        public void
                        taskPerformed(TaskEvent e) {
                                for(SamplerChannelModel c : model.getChannels()) {
                                        if(c.getChannelInfo().getEngine() == null) continue;
                                        
                                        Channel.GetFxSends gfs = new Channel.GetFxSends();
                                        gfs.setChannel(c.getChannelId());
                                        gfs.addTaskListener(new GetFxSendsListener());
                                        getTaskQueue().add(gfs);
                                }
                                
                                // TODO: This should be done after the fx sends are set
                                //CC.getSamplerModel().setModified(false);
                        }
                });
                
                
                final Global.Connect cnt = new Global.Connect();
                boolean b = preferences().getBoolProperty(JSPrefs.LAUNCH_BACKEND_LOCALLY);
                if(b && srv.isLocal() && backendProcess == null) cnt.setSilent(true);
                cnt.addTaskListener(new TaskListener() {
                        public void
                        taskPerformed(TaskEvent e) {
                                if(cnt.doneWithErrors()) {
                                        onConnectFailure();
                                        return;
                                }
                                
                                // Don't change order!!!
                                getTaskQueue().add(gsi);
                                getTaskQueue().add(gaod);
                                getTaskQueue().add(gmid);
                                getTaskQueue().add(ge);
                                getTaskQueue().add(gv);
                                getTaskQueue().add(mgim);
                                getTaskQueue().add(gfx);
                                getTaskQueue().add(new Midi.UpdateDevices());
                                getTaskQueue().add(new Audio.UpdateDevices());
                                addTask(uc);
                                getTaskQueue().add(new Global.UpdateSendEffectChains());
                                
                                int vl = preferences().getIntProperty(JSPrefs.GLOBAL_VOICE_LIMIT);
                                int sl = preferences().getIntProperty(JSPrefs.GLOBAL_STREAM_LIMIT);
                                
                                getTaskQueue().add(new Global.SetPolyphony(vl, sl));
                                
                                fireConnectionEstablishedEvent();
                        }
                });
                
                ssa.addTaskListener(new TaskListener() {
                        public void
                        taskPerformed(TaskEvent e) {
                                int t = preferences().getIntProperty(JSPrefs.SOCKET_READ_TIMEOUT);
                                CC.setClientReadTimeout(t * 1000);
                                CC.getTaskQueue().add(cnt);
                        }
                });
                
                getSamplerModel().reset();
                getViewConfig().resetInstrumentsDbTreeModel();
                
                getTaskQueue().removePendingTasks();
                getTaskQueue().add(ssa);
                
                fireReconnectEvent();
        }
        
        private static void
        onConnectFailure() {
                connectionFailureCount++;
                if(connectionFailureCount > 50) { // to prevent eventual infinite loop
                        getLogger().warning("Reached maximum number of connection failures");
                        return;
                }
                
                try {
                        if(launchBackend()) {
                                int i = preferences().getIntProperty(JSPrefs.BACKEND_LAUNCH_DELAY);
                                if(i < 1) {
                                        initSamplerModel(getCurrentServer());
                                        return;
                                }
                                
                                LaunchBackend lb = new LaunchBackend(i, getBackendMonitor());
                                //CC.getTaskQueue().add(lb);
                                new Thread(lb).start();
                                return;
                        }
                } catch(Exception x) {
                        final String s = JSI18n.i18n.getError("CC.failedToLaunchBackend");
                        CC.getLogger().log(Level.INFO, s, x);
                        
                        PDUtils.runOnUiThread(new Runnable() {
                                public void
                                run() { getViewConfig().showErrorMessage(s); }
                        });
                        return;
                }
                
                retryToConnect();
        }
        
        private static void
        retryToConnect() {
                PDUtils.runOnUiThread(new Runnable() {
                        public void
                        run() { changeBackend(); }
                });
        }
        
        public static void
        changeBackend() {
                getMainFrame().getServer(new Run<Server>() {
                        public void
                        run(Server srv) {
                                if(srv == null) return;
                                connectionFailureCount = 0; // cleared because this change is due to user interaction
                                initSamplerModel(srv);
                        }
                }, true);
        }
        
        private static final Vector<GenericListener> pListeners = new Vector<GenericListener>();
        
        /**
         * Registers the specified listener to be notified (from UI thread) when
         * backend process is created/terminated.
         * @param l The <code>ActionListener</code> to register.
         */
        public static void
        addBackendProcessListener(GenericListener l) { pListeners.add(l); }
        
        /**
         * Removes the specified listener.
         * @param l The <code>ActionListener</code> to remove.
         */
        public static void
        removeBackendProcessListener(GenericListener l) { pListeners.remove(l); }
        
        private static void
        fireBackendProcessEvent() {
                GenericEvent e = new GenericEvent(CC.class);
                for(GenericListener l : pListeners) l.jobDone(e);
        }
        
        private static Process backendProcess = null;
        
        public static Process
        getBackendProcess() { return backendProcess; }
        
        private static final Object backendMonitor = new Object();
        
        public static Object
        getBackendMonitor() { return backendMonitor; }
        
        private static boolean
        launchBackend() throws Exception {
                if(backendProcess != null) {
                        try {
                                int i = backendProcess.exitValue();
                                getLogger().info("Backend exited with exit value " + i);
                                backendProcess = null;
                                fireBackendProcessEvent();
                        } catch(IllegalThreadStateException x) { return false; }
                }
                
                if(!preferences().getBoolProperty(JSPrefs.LAUNCH_BACKEND_LOCALLY)) return false;
                if(connectionFailureCount > 1) return false;
                
                Server  s = getCurrentServer();
                if(s != null && s.isLocal()) {
                        String cmd = preferences().getStringProperty(JSPrefs.BACKEND_LAUNCH_COMMAND);
                        backendProcess = Runtime.getRuntime().exec(cmd);
                        fireBackendProcessEvent();
                        return true;
                }
                
                return false;
        }
        
        private static class GetFxSendsListener implements TaskListener {
                public void
                taskPerformed(TaskEvent e) {
                        Channel.GetFxSends gfs = (Channel.GetFxSends)e.getSource();
                        if(gfs.doneWithErrors()) return;
                        SamplerChannelModel m = getSamplerModel().getChannelById(gfs.getChannel());
                        m.removeAllFxSends();
                        
                        for(FxSend fxs : gfs.getResult()) m.addFxSend(fxs);
                }
        }
        
        public static void
        scheduleInTaskQueue(final Runnable r) {
                Task dummy = new Global.DummyTask();
                dummy.addTaskListener(new TaskListener() {
                        public void
                        taskPerformed(TaskEvent e) {
                                PDUtils.runOnUiThread(r);
                        }
                });
                
                getTaskQueue().add(dummy);
        }
        
        public static boolean
        verifyConnection() {
                if(getCurrentServer() == null) {
                        getViewConfig().showErrorMessage(i18n.getError("CC.notConnected"));
                        return false;
                }
                
                return true;
        }

        public static boolean
        isMacOS() {
                return System.getProperty("os.name").toLowerCase().startsWith("mac os x");
        }
        
        
        private final static EventHandler eventHandler = new EventHandler();
        
        private static EventHandler
        getHandler() { return eventHandler; }
        
        private static class EventHandler implements ChannelCountListener, ChannelInfoListener,
                FxSendCountListener, FxSendInfoListener, StreamCountListener, VoiceCountListener,
                TotalStreamCountListener, TotalVoiceCountListener, TaskQueueListener,
                OrchestraListener, ListListener<OrchestraModel>, MidiInstrumentCountListener,
                MidiInstrumentInfoListener, GlobalInfoListener, ChannelMidiDataListener,
                SendEffectChainCountListener, SendEffectChainInfoListener, EffectInstanceInfoListener {
                
                /** Invoked when the number of channels has changed. */
                @Override
                public void
                channelCountChanged( ChannelCountEvent e) {
                        if(e.getChannelCount() == 0) {
                                /*
                                 * This special case is handled because this might be due to
                                 * loading a lscp script containing sampler view configuration.
                                 */
                                CC.getSamplerModel().removeAllChannels();
                                return;
                        }
                        addTask(new UpdateChannels());
                }
                
                /** Invoked when changes to the sampler channel has occured. */
                @Override
                public void
                channelInfoChanged(ChannelInfoEvent e) {
                        /*
                         * Because of the rapid notification flow when instrument is loaded
                         * we need to do some optimization to decrease the traffic.
                         */
                        boolean b = true;
                        Task[] tS = getTaskQueue().getPendingTasks();
                        
                        for(int i = tS.length - 1; i >= 0; i--) {
                                Task t = tS[i];
                                
                                if(t instanceof Channel.UpdateInfo) {
                                        Channel.UpdateInfo cui = (Channel.UpdateInfo)t;
                                        if(cui.getChannelId() == e.getSamplerChannel()) return;
                                } else {
                                        b = false;
                                        break;
                                }
                        }
                        
                        if(b) {
                                Task t = getTaskQueue().getRunningTask();
                                if(t instanceof Channel.UpdateInfo) {
                                        Channel.UpdateInfo cui = (Channel.UpdateInfo)t;
                                        if(cui.getChannelId() == e.getSamplerChannel()) return;
                                }
                        }
                        
                        
                        getTaskQueue().add(new Channel.UpdateInfo(e.getSamplerChannel()));
                }
                
                /**
                 * Invoked when the number of effect sends
                 * on a particular sampler channel has changed.
                 */
                @Override
                public void
                fxSendCountChanged(FxSendCountEvent e) {
                        getTaskQueue().add(new Channel.UpdateFxSends(e.getChannel()));
                }
                
                /**
                 * Invoked when the settings of an effect sends are changed.
                 */
                @Override
                public void
                fxSendInfoChanged(FxSendInfoEvent e) {
                        Task t = new Channel.UpdateFxSendInfo(e.getChannel(), e.getFxSend());
                        getTaskQueue().add(t);
                }
                
                /**
                 * Invoked when the number of active disk
                 * streams in a specific sampler channel has changed.
                 */
                @Override
                public void
                streamCountChanged(StreamCountEvent e) {
                        SamplerChannelModel scm = 
                                getSamplerModel().getChannelById(e.getSamplerChannel());
                        
                        if(scm == null) {
                                CC.getLogger().log (
                                        Level.WARNING,
                                        "CC.unknownChannel!",
                                        e.getSamplerChannel()
                                );
                                
                                return;
                        }
                        
                        scm.setStreamCount(e.getStreamCount());
                }
                
                /**
                 * Invoked when the number of active voices
                 * in a specific sampler channel has changed.
                 */
                @Override
                public void
                voiceCountChanged(VoiceCountEvent e) {
                        SamplerChannelModel scm = 
                                getSamplerModel().getChannelById(e.getSamplerChannel());
                        
                        if(scm == null) {
                                CC.getLogger().log (
                                        Level.WARNING,
                                        "CC.unknownChannel!",
                                        e.getSamplerChannel()
                                );
                                
                                return;
                        }
                        
                        scm.setVoiceCount(e.getVoiceCount());
                }
                
                /** Invoked when the total number of active streams has changed. */
                @Override
                public void
                totalStreamCountChanged(TotalStreamCountEvent e) {
                        getSamplerModel().updateActiveStreamsInfo(e.getTotalStreamCount());
                }
                
                /** Invoked when the total number of active voices has changed. */
                @Override
                public void
                totalVoiceCountChanged(TotalVoiceCountEvent e) {
                        scheduleTask(new Global.UpdateTotalVoiceCount());
                }
                
                /** Invoked when the number of MIDI instruments in a MIDI instrument map is changed. */
                @Override
                public void
                instrumentCountChanged(MidiInstrumentCountEvent e) {
                        scheduleTask(new Midi.UpdateInstruments(e.getMapId()));
                }
                
                /** Invoked when a MIDI instrument in a MIDI instrument map is changed. */
                @Override
                public void
                instrumentInfoChanged(MidiInstrumentInfoEvent e) {
                        Task t = new Midi.UpdateInstrumentInfo (
                                e.getMapId(), e.getMidiBank(), e.getMidiProgram()
                        ); 
                        getTaskQueue().add(t);
                                
                }
                
                /** Invoked when the global volume of the sampler is changed. */
                @Override
                public void
                volumeChanged(GlobalInfoEvent e) {
                        getSamplerModel().setVolume(e.getVolume());
                }
                
                @Override
                public void
                voiceLimitChanged(GlobalInfoEvent e) { }
                
                @Override
                public void
                streamLimitChanged(GlobalInfoEvent e) { }
                
                /**
                 * Invoked to indicate that the state of a task queue is changed.
                 * This method is invoked only from the UI thread.
                 */
                @Override
                public void
                stateChanged(TaskQueueEvent e) {
                        switch(e.getEventID()) {
                        case TASK_FETCHED:
                                getProgressIndicator().setString (
                                        ((Task)e.getSource()).getDescription()
                                );
                                break;
                        case TASK_DONE:
                                EnhancedTask t = (EnhancedTask)e.getSource();
                                if(t.doneWithErrors() && !t.isSilent()) {
                                        if(t.getErrorCode() == t.SOCKET_ERROR) {
                                                getMainFrame().handleConnectionFailure();
                                        } else if(!t.isStopped()) {
                                                showError(t);
                                        }
                                }
                                break;
                        case NOT_IDLE:
                                if(progressTimerTask != null) {
                                        getLogger().warning("progressTimerTask != null - this is a bug!");
                                }
                                progressTimerTask = new ProgressTimerTask();
                                timer.schedule(progressTimerTask, 2000);
                                break;
                        case IDLE:
                                if(progressTimerTask != null) {
                                        progressTimerTask.cancel();
                                        progressTimerTask = null;
                                }
                                getProgressIndicator().stop();
                                break;
                        }
                }
                
                private void
                showError(final Task t) {
                        PDUtils.runOnUiThread(new Runnable() {
                                public void
                                run() {
                                        if(t.getErrorDetails() == null) {
                                                getViewConfig().showErrorMessage(t.getErrorMessage());
                                        } else {
                                                getMainFrame().showDetailedErrorMessage (
                                                        t.getErrorMessage(),
                                                        t.getErrorDetails()
                                                );
                                        }
                                }
                        });
                }
                
                /** Invoked when the name of orchestra is changed. */
                @Override
                public void
                nameChanged(OrchestraEvent e) { saveOrchestras(); }
        
                /** Invoked when the description of orchestra is changed. */
                @Override
                public void
                descriptionChanged(OrchestraEvent e) { saveOrchestras(); }
        
                /** Invoked when an instrument is added to the orchestra. */
                @Override
                public void
                instrumentAdded(OrchestraEvent e) { saveOrchestras(); }
        
                /** Invoked when an instrument is removed from the orchestra. */
                @Override
                public void
                instrumentRemoved(OrchestraEvent e) { saveOrchestras(); }
        
                /** Invoked when the settings of an instrument are changed. */
                @Override
                public void
                instrumentChanged(OrchestraEvent e) { saveOrchestras(); }
                
                /** Invoked when an orchestra is added to the orchestra list. */
                @Override
                public void
                entryAdded(ListEvent<OrchestraModel> e) {
                        e.getEntry().addOrchestraListener(getHandler());
                        saveOrchestras();
                }
        
                /** Invoked when an orchestra is removed from the orchestra list. */
                @Override
                public void
                entryRemoved(ListEvent<OrchestraModel> e) {
                        e.getEntry().removeOrchestraListener(getHandler());
                        saveOrchestras();
                }
                
                /**
                 * Invoked when MIDI data arrives.
                 */
                @Override
                public void
                midiDataArrived(final ChannelMidiDataEvent e) {
                        try {
                                PDUtils.runOnUiThreadAndWait(new Runnable() {
                                        public void
                                        run() { fireChannelMidiDataEvent(e); }
                                });
                        } catch(Exception x) {
                                CC.getLogger().log(Level.INFO, "Failed!", x);
                        }
                }
                
                @Override
                public void
                sendEffectChainCountChanged(SendEffectChainCountEvent e) {
                        getTaskQueue().add(new Audio.UpdateSendEffectChains(e.getAudioDeviceId()));
                }
                
                @Override
                public void
                sendEffectChainInfoChanged(SendEffectChainInfoEvent e) {
                        if(e.getInstanceCount() == -1) return;
                        
                        getTaskQueue().add (
                                new Audio.UpdateEffectInstances(e.getAudioDeviceId(), e.getChainId())
                        );
                }
                
                @Override
                public void
                effectInstanceInfoChanged(EffectInstanceInfoEvent e) {
                        getTaskQueue().add(new Audio.UpdateEffectInstanceInfo(e.getEffectInstanceId()));
                }
        }
        
        private static void
        fireChannelMidiDataEvent(ChannelMidiDataEvent e) {
                SamplerChannelModel chn;
                chn = getSamplerModel().getChannelById(e.getChannelId());
                if(chn == null) {
                        CC.getLogger().info("Unknown channel ID: " + e.getChannelId());
                }
                
                ((DefaultSamplerChannelModel)chn).fireMidiDataEvent(e);
        }
        
        private static final AudioDeviceCountListener audioDeviceCountListener = 
                new AudioDeviceCountListener();
        
        private static class AudioDeviceCountListener implements ItemCountListener {
                /** Invoked when the number of audio output devices has changed. */
                @Override
                public void
                itemCountChanged(ItemCountEvent e) {
                        getTaskQueue().add(new Audio.UpdateDevices());
                }
        }
        
        private static final AudioDeviceInfoListener audioDeviceInfoListener = 
                new AudioDeviceInfoListener();
        
        private static class AudioDeviceInfoListener implements ItemInfoListener {
                /** Invoked when the audio output device's settings are changed. */
                @Override
                public void
                itemInfoChanged(ItemInfoEvent e) {
                        getTaskQueue().add(new Audio.UpdateDeviceInfo(e.getItemID()));
                }
        }
        
        private static final MidiDeviceCountListener midiDeviceCountListener = 
                new MidiDeviceCountListener();
        
        private static class MidiDeviceCountListener implements ItemCountListener {
                /** Invoked when the number of MIDI input devices has changed. */
                public void
                itemCountChanged(ItemCountEvent e) {
                        getTaskQueue().add(new Midi.UpdateDevices());
                }
        }
        
        private static final MidiDeviceInfoListener midiDeviceInfoListener = 
                new MidiDeviceInfoListener();
        
        private static class MidiDeviceInfoListener implements ItemInfoListener {
                /** Invoked when the MIDI input device's settings are changed. */
                @Override
                public void
                itemInfoChanged(ItemInfoEvent e) {
                        getTaskQueue().add(new Midi.UpdateDeviceInfo(e.getItemID()));
                }
        }
        
        private static final MidiInstrMapCountListener midiInstrMapCountListener = 
                new MidiInstrMapCountListener();
        
        private static class MidiInstrMapCountListener implements ItemCountListener {
                /** Invoked when the number of MIDI instrument maps is changed. */
                @Override
                public void
                itemCountChanged(ItemCountEvent e) {
                        getTaskQueue().add(new Midi.UpdateInstrumentMaps());
                }
        }
        
        private static final MidiInstrMapInfoListener midiInstrMapInfoListener = 
                new MidiInstrMapInfoListener();
        
        private static class MidiInstrMapInfoListener implements ItemInfoListener {
                /** Invoked when the MIDI instrument map's settings are changed. */
                @Override
                public void
                itemInfoChanged(ItemInfoEvent e) {
                        getTaskQueue().add(new Midi.UpdateInstrumentMapInfo(e.getItemID()));
                }
        }
}