/*
 * Copyright (c) 2014, 2015, Dynatrace and/or its affiliates. All rights reserved.
 * 
 * This file is part of the Lock Contention Tracing Subsystem for the HotSpot
 * Virtual Machine, which is developed at Christian Doppler Laboratory on
 * Monitoring and Evolution of Very-Large-Scale Software Systems. Please
 * contact us at <http://mevss.jku.at/> if you need additional information
 * or have any questions.
 *
 * 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.
 *
 * 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, see <http://www.gnu.org/licenses/>.
 *
 */ 
package sun.evtracing.processing.statistics;

import java.io.FileNotFoundException;
import java.io.PrintStream;
import java.util.stream.Collectors;
import java.util.stream.StreamSupport;

import sun.evtracing.parser.SequenceOrderedEvent;
import sun.evtracing.parser.metadata.JavaStack;
import sun.evtracing.parser.metadata.JavaThread;
import sun.evtracing.processing.statistics.metadata.ParkEventTuple;

public class ParkEventTupleJsonSerializer {
	private final PrintStream ps;
	private final ParkEventTuple tuple;
	private final boolean seqAsTimestamp;
	private long flowId;

	public static void serialize(String outputFile, ParkEventTuple tuple, boolean seqAsTimestamp) {
		try {
			ParkEventTupleJsonSerializer serializer = new ParkEventTupleJsonSerializer(new PrintStream(outputFile), tuple, seqAsTimestamp);
			serializer.serialize();
		} catch (FileNotFoundException e) {
			throw new RuntimeException(e);
		}
	}

	public ParkEventTupleJsonSerializer(PrintStream ps, ParkEventTuple tuple, boolean seqAsTimestamp) {
		this.ps = ps;
		this.tuple = tuple;
		this.seqAsTimestamp = seqAsTimestamp;
		flowId = 0;
	}

	private void serialize() {
		ps.println("[");
		ps.print("{\"name\":\"process_name\",\"ph\":\"M\",\"pid\":1,\"args\":{\"name\":\"java\"}}");
		printTuple(tuple);
		for (ParkEventTuple t : tuple.overlapping()) {
			printTuple(t);
		}
		ps.println("\n]");
	}

	private void printTuple(ParkEventTuple tuple) {
		printThread(tuple.begin().thread().metadata());
		if (tuple.unpark() != null) {
			printThread(tuple.unpark().thread().metadata());
		}

		String name = tuple.begin().clazz().metadata().prettyName(true);
		long startTime = timeFrom(tuple.begin());
		long thread = tuple.begin().thread().identifier();
		String isAbsolute = String.valueOf(tuple.begin().isAbsolute());
		long parkTime = tuple.begin().parkTime();
		String objectHash = Integer.toHexString(tuple.begin().blockerObject());
		JavaStack jstack = tuple.begin().stack().metadata();
		String stack;
		if (jstack.isSet()) {
			stack = StreamSupport.stream(jstack.spliterator(), false)
						.map(frame -> "\"" + (frame.method().isSet() ? frame.method().prettyDescriptor(true) : "(unknown)") + "\"")
						.collect(Collectors.joining(","));
		} else {
			stack = "";
		}
		int nestingLevel = tuple.begin().nestingLevel();
		long endTime = timeFrom(tuple.end());
		long duration = endTime - startTime;
		long beginSeq = tuple.begin().sequenceNumber();
		long unparkSeq = tuple.end().unparkSequenceNumber();
		long endSeq = tuple.end().sequenceNumber();
		String parkReturnCode = tuple.end().parkReturnCode().name();
		ps.printf(",\n{\"name\":\"%s\",\"cat\":\"park\",\"ph\":\"X\",\"ts\":%d,\"dur\":%d,\"pid\":1,\"tid\":%d,\"args\":{\"Arg isAbsolute\":%s,\"Arg time\":%d,\"Identity Hash Code\":\"%s\",\"Stack\":[%s],\"Nesting Level\":%d,\"Seq Begin\":%d,\"Seq Unpark\":%d,\"Seq End\":%d,\"Return Code\":\"%s\"}}",
				name, startTime, duration, thread, isAbsolute, parkTime, objectHash, stack, nestingLevel, beginSeq, unparkSeq, endSeq, parkReturnCode);

		if (tuple.unpark() != null) {
			flowId++;
			long unparkTime = timeFrom(tuple.unpark());
			ps.printf(",\n{\"name\":\"unpark\",\"cat\":\"park\",\"ph\":\"%s\",\"ts\":%d,\"id\":%d,\"pid\":1,\"tid\":%d}", unparkTime < endTime ? "s" : "f", unparkTime, flowId, tuple.unpark().thread().identifier());
			ps.printf(",\n{\"name\":\"unparked\",\"cat\":\"park\",\"ph\":\"%s\",\"ts\":%d,\"id\":%d,\"pid\":1,\"tid\":%d}", unparkTime < endTime ? "f" : "s", endTime, flowId, tuple.unpark().unparkedThread().identifier());
		}
	}

	private void printThread(JavaThread thread) {
		ps.printf(",\n{\"name\":\"thread_name\",\"ph\":\"M\",\"pid\":1,\"tid\":%d,\"args\":{\"name\":\"%s\"}}", thread.threadId(), thread.name());
	}

	private long timeFrom(SequenceOrderedEvent e) {
		if (seqAsTimestamp) {
			return e.sequenceNumber();
		} else {
			return e.timestamp() / 1000;
		}
	}
}