/*
 * Copyright (c) 2019 Hemanth Savarala.
 *
 * Licensed under the GNU General Public License v3
 *
 * This is free software: you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by
 *  the Free Software Foundation either version 3 of the License, or (at your option) any later version.
 *
 * This software 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 for more details.
 */

package code.name.monkey.retromusic.misc;

import android.util.Log;

import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.TimeUnit;

public class LagTracker {
  private static Map<String, Long> mMap;
  private static LagTracker mSingleton;
  private boolean mEnabled = true;

  private LagTracker() {
    mMap = new HashMap<>();
  }

  public static LagTracker get() {
    if (mSingleton == null) {
      mSingleton = new LagTracker();
    }
    return mSingleton;
  }

  private void print(String str, long j) {
    long toMillis = TimeUnit.NANOSECONDS.toMillis(j);
    Log.d(
        "LagTracker",
        "["
            + str
            + " completed in]: "
            + j
            + " ns ("
            + toMillis
            + "ms, "
            + TimeUnit.NANOSECONDS.toSeconds(j)
            + "s)");
  }

  public LagTracker disable() {
    this.mEnabled = false;
    return this;
  }

  public LagTracker enable() {
    this.mEnabled = true;
    return this;
  }

  public void end(String str) {
    long nanoTime = System.nanoTime();
    if (this.mEnabled) {
      if (mMap.containsKey(str)) {
        print(str, nanoTime - mMap.get(str));
        mMap.remove(str);
        return;
      }
      throw new IllegalStateException("No start time found for " + str);
    } else if (!mMap.isEmpty()) {
      mMap.clear();
    }
  }

  public void start(String str) {
    long nanoTime = System.nanoTime();
    if (this.mEnabled) {
      mMap.put(str, nanoTime);
    } else if (!mMap.isEmpty()) {
      mMap.clear();
    }
  }
}