/*
 * Copyright 2012-2017 Red Hat, Inc.
 *
 * This file is part of Thermostat.
 *
 * Thermostat is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation; either version 2, or (at your
 * option) any later version.
 *
 * Thermostat 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 Thermostat; see the file COPYING.  If not see
 * <http://www.gnu.org/licenses/>.
 *
 * Linking this code with other modules is making a combined work
 * based on this code.  Thus, the terms and conditions of the GNU
 * General Public License cover the whole combination.
 *
 * As a special exception, the copyright holders of this code give
 * you permission to link this code with independent modules to
 * produce an executable, regardless of the license terms of these
 * independent modules, and to copy and distribute the resulting
 * executable under terms of your choice, provided that you also
 * meet, for each linked independent module, the terms and conditions
 * of the license of that module.  An independent module is a module
 * which is not derived from or based on this code.  If you modify
 * this code, you may extend this exception to your version of the
 * library, but you are not obligated to do so.  If you do not wish
 * to do so, delete this exception statement from your version.
 */

package com.redhat.thermostat.agent.command.server.internal;

import java.io.IOException;

import com.redhat.thermostat.common.utils.LoggingUtils;
import com.redhat.thermostat.shared.config.CommonPaths;
import com.redhat.thermostat.shared.config.InvalidConfigurationException;
import com.redhat.thermostat.shared.config.SSLConfiguration;
import com.redhat.thermostat.shared.config.internal.CommonPathsImpl;

public class CommandChannelServerMain {
    
    private static SSLConfigurationParser sslConfParser = new SSLConfigurationParser();
    private static ServerCreator serverCreator = new ServerCreator();
    private static ShutdownHookHandler shutdownHandler = new ShutdownHookHandler();
    private static Sleeper sleeper = new Sleeper();
    private static LoggingInitializer logInit = new LoggingInitializer();
    private static CommandChannelServerImpl impl = null;

    // TODO Add some keep alive check
    public static void main(String[] args) {
        if (args.length != 2) {
            System.err.println("usage: thermostat-command-channel hostname port");
            return;
        }
        String hostname = args[0];
        Integer port;
        try {
            port = Integer.valueOf(args[1]);
        } catch (NumberFormatException e) {
            System.err.println("port number must be a valid integer");
            return;
        }
        
        // Initialize logging
        logInit.initialize();
        
        try {
            SSLConfiguration config = sslConfParser.parse(System.in);
            
            impl = serverCreator.createServer(config);
            
            // Start listening on server
            impl.startListening(hostname, port);
            
            shutdownHandler.addShutdownHook(new Thread(new Runnable() {
                @Override
                public void run() {
                    impl.stopListening();
                }
            }));
            
            sleeper.sleepWait();
        } catch (IOException e) {
            System.err.println("Failed to start command channel server");
            e.printStackTrace();
            if (impl != null) {
                impl.stopListening();
            }
        }
    }
    
    static class ServerCreator {
        CommandChannelServerImpl createServer(SSLConfiguration sslConf) {
            CommandChannelServerContext ctx = new CommandChannelServerContext(sslConf);
            return new CommandChannelServerImpl(ctx);
        }
    }
    
    static class ShutdownHookHandler {
        void addShutdownHook(Thread hook) {
            Runtime.getRuntime().addShutdownHook(hook);
        }
    }
    
    static class Sleeper {
        void sleepWait() {
            while (!Thread.interrupted()) {
                try {
                    Thread.sleep(1000);
                } catch (InterruptedException e) {
                    Thread.currentThread().interrupt();
                }
            }
        }
    }
    
    // Taken from LauncherImpl
    static class LoggingInitializer {
        void initialize() {
            CommonPaths paths = new CommonPathsImpl();
            try {
                LoggingUtils.loadGlobalLoggingConfig(paths);
            } catch (InvalidConfigurationException e) {
                System.err.println("WARNING: Could not read global Thermostat logging configuration.");
            }
            try {
                LoggingUtils.loadUserLoggingConfig(paths);
            } catch (InvalidConfigurationException e) {
                // We intentionally ignore this.
            }
        }
    }
    
    /* For testing purposes only */
    static void setSSLConfigurationParser(SSLConfigurationParser parser) {
        CommandChannelServerMain.sslConfParser = parser;
    }
    
    /* For testing purposes only */
    static void setServerCreator(ServerCreator creator) {
        CommandChannelServerMain.serverCreator = creator;
    }
    
    /* For testing purposes only */
    static void setShutdownHookHandler(ShutdownHookHandler handler) {
        CommandChannelServerMain.shutdownHandler = handler;
    }
    
    /* For testing purposes only */
    static void setSleeper(Sleeper sleeper) {
        CommandChannelServerMain.sleeper = sleeper;
    }
    
    /* For testing purposes only */
    static void setLoggingInitializer(LoggingInitializer logInit) {
        CommandChannelServerMain.logInit = logInit;
    }
    
}