/*
    * Copyright (C) 2019, Matthias Sohn <matthias.sohn@sap.com> and others
    *
    * This program and the accompanying materials are made available under the
    * terms of the Eclipse Distribution License v. 1.0 which is available at
    * https://www.eclipse.org/org/documents/edl-v10.php.
    *
    * SPDX-License-Identifier: BSD-3-Clause
    */
  package org.eclipse.jgit.benchmarks;
  
  import java.io.IOException;
  import java.nio.file.Files;
  import java.nio.file.Path;
  import java.util.concurrent.TimeUnit;
  
  import org.eclipse.jgit.internal.storage.file.FileSnapshot;
  import org.eclipse.jgit.util.FileUtils;
  import org.openjdk.jmh.annotations.Benchmark;
  import org.openjdk.jmh.annotations.BenchmarkMode;
  import org.openjdk.jmh.annotations.Measurement;
  import org.openjdk.jmh.annotations.Mode;
  import org.openjdk.jmh.annotations.OutputTimeUnit;
  import org.openjdk.jmh.annotations.Scope;
  import org.openjdk.jmh.annotations.Setup;
  import org.openjdk.jmh.annotations.State;
  import org.openjdk.jmh.annotations.TearDown;
  import org.openjdk.jmh.annotations.Warmup;
  import org.openjdk.jmh.runner.Runner;
  import org.openjdk.jmh.runner.RunnerException;
  import org.openjdk.jmh.runner.options.Options;
  import org.openjdk.jmh.runner.options.OptionsBuilder;
  
  @State(Scope.Thread)
  public class CreateFileSnapshotBenchmark {
  
  	Path path;
  
  	Path testDir;
  
  	@Setup
  	public void setupBenchmark() throws IOException {
  		testDir = Files.createTempDirectory("dir");
  		path = testDir.resolve("toSnapshot");
  		Files.createFile(path);
  	}
  
  	@TearDown
  	public void teardown() throws IOException {
  		FileUtils.delete(testDir.toFile(), FileUtils.RECURSIVE | FileUtils.RETRY);
  	}
  
  	@Benchmark
  	@BenchmarkMode({ Mode.AverageTime })
  	@OutputTimeUnit(TimeUnit.NANOSECONDS)
      @Warmup(iterations = 5, time = 100, timeUnit = TimeUnit.MILLISECONDS)
      @Measurement(iterations = 5, time = 100, timeUnit = TimeUnit.MILLISECONDS)
  	public Path testCreateFile() throws IOException {
  		return Files.createTempFile(testDir, "create", "");
  	}
  
  	@Benchmark
  	@BenchmarkMode({ Mode.AverageTime })
  	@OutputTimeUnit(TimeUnit.NANOSECONDS)
  	public FileSnapshot testCreateFileSnapshot() {
  		return FileSnapshot.save(path.toFile());
  	}
  
  	public static void main(String[] args) throws RunnerException {
  		Options opt = new OptionsBuilder()
  				.include(CreateFileSnapshotBenchmark.class.getSimpleName())
  				// .addProfiler(StackProfiler.class)
  				// .addProfiler(GCProfiler.class)
  				.forks(1).jvmArgs("-ea").build();
  		new Runner(opt).run();
  	}
  }