/*******************************************************************************
 * Copyright (c) 2004, 2007 Boeing.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Boeing - initial API and implementation
 *******************************************************************************/
package org.eclipse.osee.ote.message.tool.rec;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.WritableByteChannel;
import java.util.ArrayList;
import java.util.Collection;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
import java.util.logging.Level;
import org.eclipse.osee.framework.jdk.core.type.OseeCoreException;
import org.eclipse.osee.framework.logging.OseeLog;
import org.eclipse.osee.ote.core.environment.TestEnvironmentInterface;
import org.eclipse.osee.ote.core.internal.Activator;
import org.eclipse.osee.ote.message.MessageSystemTestEnvironment;
import org.eclipse.osee.ote.message.tool.rec.entry.IMessageEntry;

public class MessageRecorder {
   private static final int NUM_BUFFERS = 3;
   private WritableByteChannel channel;

   private final ArrayList<IMessageEntry> msgsToRecord = new ArrayList<>(64);
   private final Lock recLock = new ReentrantLock();
   private volatile boolean isRecording = false;
   private final IMessageEntryFactory factory;

   private final ExecutorService taskHandler = Executors.newFixedThreadPool(2);
   private final ArrayBlockingQueue<ByteBuffer> bufferQueue = new ArrayBlockingQueue<>(NUM_BUFFERS);

   public MessageRecorder(IMessageEntryFactory factory) {
      this.factory = factory;
      try {
         for (int i = 0; i < NUM_BUFFERS; i++) {
            bufferQueue.put(ByteBuffer.allocateDirect(256000));
         }
      } catch (InterruptedException e) {
         // this should be absolutely impossible
         throw new Error("What on Earth has happened here!", e);
      }
   }

   public void startRecording(Collection<MessageRecordConfig> list, WritableByteChannel channel) throws OseeCoreException {
      if (list == null) {
         throw new IllegalArgumentException("list cannot be null");
      }
      if (channel == null) {
         throw new IllegalArgumentException("channel cannot be null");
      }
      recLock.lock();
      try {
         this.channel = channel;
         for (MessageRecordConfig config : list) {
            IMessageEntry handler = factory.createMessageEntry(config, this);
            msgsToRecord.add(handler);
            handler.enable(true);
         }
         OseeLog.log(MessageSystemTestEnvironment.class, Level.INFO, "recording " + list.size() + "messages");
         isRecording = true;
      } finally {
         recLock.unlock();
      }
   }

   public ByteBuffer acquireOutputBuffer() throws InterruptedException {
      return bufferQueue.take();
   }

   public void releaseOutputBuffer(ByteBuffer buffer) throws InterruptedException {
      bufferQueue.put(buffer);
   }

   public WritableByteChannel getChannel() {
      return channel;
   }

   public Future<?> submitTask(Runnable task) {
      return taskHandler.submit(task);
   }

   public boolean isRecording() {
      return isRecording;
   }

   public void stopRecording(boolean closeOutputChannel) throws IOException {
      OseeLog.log(MessageSystemTestEnvironment.class, Level.INFO, "stopping message recorder...");
      isRecording = false;
      recLock.lock();
      try {
         for (IMessageEntry handler : msgsToRecord) {
            handler.enable(false);
         }
         msgsToRecord.clear();
         if (closeOutputChannel) {
            channel.close();
         }
      } finally {
         recLock.unlock();
         OseeLog.log(MessageSystemTestEnvironment.class, Level.INFO, "message recorder stopped");
      }
   }
}