package com.github.davidmoten.rx2.internal;
   
   import java.util.concurrent.TimeUnit;
   import java.util.regex.Matcher;
   import java.util.regex.Pattern;
   
   import io.reactivex.Scheduler;
   import io.reactivex.disposables.Disposable;
   
  public final class SchedulerWithId extends Scheduler {
  
      private final Scheduler scheduler;
      private final String id;
      private final static Pattern pattern = Pattern.compile("\\bschedId=\\[[^\\]]+\\]+\\b");
  
      public SchedulerWithId(Scheduler scheduler, String id) {
          this.scheduler = scheduler;
          this.id = "[" + id + "]";
      }
  
      @Override
      public Worker createWorker() {
  
          final Worker worker = scheduler.createWorker();
          Worker w = new Worker() {
  
              @Override
              public Disposable schedule(final Runnable action, long delayTime, TimeUnit unit) {
                  Runnable a = new Runnable() {
                      @Override
                      public void run() {
                          String name = null;
                          try {
                              name = setThreadName();
                              action.run();
                          } finally {
                              if (name != null) {
                                  Thread.currentThread().setName(name);
                              }
                          }
                      }
                  };
                  return worker.schedule(a, delayTime, unit);
              }
  
              @Override
              public void dispose() {
                  worker.dispose();
              }
  
              @Override
              public boolean isDisposed() {
                  return worker.isDisposed();
              }
  
          };
          return w;
  
      }
  
      private String setThreadName() {
          String name = Thread.currentThread().getName();
          String newName = updateNameWithId(name, id);
          Thread.currentThread().setName(newName);
          return name;
      }
  
      private static String updateNameWithId(String name, String id) {
          final String newName;
          if (name == null) {
              newName = id;
          } else {
              Matcher matcher = pattern.matcher(name);
              if (matcher.find()) {
                  newName = name.replace(matcher.group(), "schedId=" + id);
              } else {
                  newName = name + "|schedId=" + id;
              }
          }
          return newName;
      }
  
  }