/*
 * Copyright (c) 2008-2012, Hazel Bilisim Ltd. All Rights Reserved.
 *
 * 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.hazelcast.client;

import com.hazelcast.core.LifecycleEvent;
import com.hazelcast.core.LifecycleEvent.LifecycleState;
import com.hazelcast.core.LifecycleListener;
import com.hazelcast.core.LifecycleService;
import com.hazelcast.logging.ILogger;
import com.hazelcast.logging.Logger;

import java.util.concurrent.*;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.logging.Level;

import static com.hazelcast.core.LifecycleEvent.LifecycleState.*;

public class LifecycleServiceClientImpl implements LifecycleService {
    final static ILogger logger = Logger.getLogger(LifecycleServiceClientImpl.class.getName());
    final AtomicBoolean paused = new AtomicBoolean(false);
    final AtomicBoolean running = new AtomicBoolean(true);
    final CopyOnWriteArrayList<LifecycleListener> lsLifecycleListeners = new CopyOnWriteArrayList<LifecycleListener>();
    final Object lifecycleLock = new Object();
    final HazelcastClient hazelcastClient;
    final ExecutorService es = Executors.newSingleThreadExecutor();

    public LifecycleServiceClientImpl(HazelcastClient hazelcastClient) {
        this.hazelcastClient = hazelcastClient;
    }

    public void addLifecycleListener(LifecycleListener lifecycleListener) {
        lsLifecycleListeners.add(lifecycleListener);
    }

    public void removeLifecycleListener(LifecycleListener lifecycleListener) {
        lsLifecycleListeners.remove(lifecycleListener);
    }

    public void fireLifecycleEvent(final LifecycleState lifecycleState) {
        callAsync(new Callable<Object>() {
            public Object call() throws Exception {
                fireLifecycleEvent(new LifecycleEvent(lifecycleState));
                return null;
            }
        });
    }

    private void callAsync(final Callable callable) {
            es.submit(callable);
    }

    public void fireLifecycleEvent(final LifecycleEvent event) {
        logger.log(Level.INFO, "HazelcastClient is " + event.getState());
        for (LifecycleListener lifecycleListener : lsLifecycleListeners) {
            lifecycleListener.stateChanged(event);
        }
    }

    public boolean resume() {
        Callable<Boolean> callable = new Callable<Boolean>() {
            public Boolean call() {
                synchronized (lifecycleLock) {
                    if (paused.get()) {
                        fireLifecycleEvent(RESUMING);
                    } else {
                        return false;
                    }
                    paused.set(false);
                    fireLifecycleEvent(RESUMED);
                    return true;
                }
            }
        };
        return hazelcastClient.callAsyncAndWait(callable);
    }

    public boolean pause() {
        Callable<Boolean> callable = new Callable<Boolean>() {
            public Boolean call() {
                synchronized (lifecycleLock) {
                    if (!paused.get()) {
                        fireLifecycleEvent(PAUSING);
                    } else {
                        return false;
                    }
                    paused.set(true);
                    fireLifecycleEvent(PAUSED);
                    return true;
                }
            }
        };
        return hazelcastClient.callAsyncAndWait(callable);
    }

    public void shutdown() {
        Callable<Boolean> callable = new Callable<Boolean>() {
            public Boolean call() {
                synchronized (lifecycleLock) {
                    long begin = System.currentTimeMillis();
                    fireLifecycleEvent(SHUTTING_DOWN);
                    hazelcastClient.doShutdown();
                    running.set(false);
                    long time = System.currentTimeMillis() - begin;
                    logger.log(Level.FINE, "HazelcastClient shutdown completed in " + time + " ms.");
                    fireLifecycleEvent(SHUTDOWN);
                    return true;
                }
            }
        };
        hazelcastClient.callAsyncAndWait(callable);
        try {
            Thread.sleep(1000);
        } catch (InterruptedException ignore) {
        }
        es.shutdown();
    }

    public void kill() {
        shutdown();
    }

    public void restart() {
        throw new UnsupportedOperationException();
    }

    public boolean isRunning() {
        return running.get();
    }
}