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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
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package jdk.jfr.internal.management;

import java.io.IOException;
import java.io.InputStream;
import java.time.Instant;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import java.util.Timer;
import java.util.concurrent.TimeUnit;

import jdk.jfr.Recording;
import jdk.jfr.internal.consumer.FinishedStream;
import jdk.jfr.internal.consumer.OngoingStream;

// Exposes EventByteStreams to the FlightRecorderMXBean
public final class StreamManager {

    public static final long TIME_OUT = TimeUnit.MINUTES.toMillis(200);
    public static final int DEFAULT_BLOCK_SIZE = 50000;

    private final Map<Long, EventByteStream> streams = new HashMap<>();
    private Timer timer;

    public synchronized EventByteStream getStream(long streamIdentifer) {
        EventByteStream stream = streams.get(streamIdentifer);
        if (stream == null) {
            throw new IllegalArgumentException("Unknown stream identifier " + streamIdentifer);
        }
        return stream;
    }

    public synchronized EventByteStream createOngoing(Recording recording, int blockSize, Instant startTime, Instant endTime) {
        long startTimeNanos = 0;
        long endTimeNanos = Long.MAX_VALUE;
        if (!startTime.equals(Instant.MIN)) {
           startTimeNanos = startTime.getEpochSecond() * 1_000_000_000L;
           startTimeNanos += startTime.getNano();
        }
        if (!endTime.equals(Instant.MAX)) {
            endTimeNanos =  endTime.getEpochSecond() * 1_000_000_000L;
            endTimeNanos+= endTime.getNano();
        }
        EventByteStream stream = EventByteStream.newOngoingStream(recording, blockSize, startTimeNanos, endTimeNanos);
        streams.put(stream.getId(), stream);
        scheduleAbort(stream, System.currentTimeMillis() + TIME_OUT);
        return stream;
    }

    public synchronized EventByteStream create(InputStream is, int blockSize) {
        EventByteStream stream = EventByteStream.newFinishedStream(is, blockSize);
        streams.put(stream.getId(), stream);

        scheduleAbort(stream, System.currentTimeMillis() + TIME_OUT);
        return stream;
    }

    public synchronized void destroy(EventByteStream stream) {
        try {
            stream.close();
        } catch (IOException e) {
            // OK
        }
        streams.remove(stream.getId());
        if (streams.isEmpty()) {
            timer.cancel();
            timer = null;
        }
    }

    public synchronized void scheduleAbort(EventByteStream s, long when) {
        if (timer == null) {
            timer = new Timer(true);
        }
        timer.schedule(new StreamCleanupTask(this, s), new Date(when + TIME_OUT));
    }
}