/**
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
    * with the License.  You may obtain a copy of the License at
    *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.hadoop.hbase;
  
  import java.io.PrintWriter;
  import java.io.StringWriter;
  import java.lang.management.LockInfo;
  import java.lang.management.ManagementFactory;
  import java.lang.management.MonitorInfo;
  import java.lang.management.ThreadInfo;
  import java.lang.management.ThreadMXBean;
  import java.text.DateFormat;
  import java.text.SimpleDateFormat;
  import java.util.Date;
  import java.util.Locale;
  import java.util.Map;
  
  import org.junit.runner.notification.Failure;
  import org.junit.runner.notification.RunListener;
  
  /**
   * JUnit run listener which prints full thread dump into System.err
   * in case a test is failed due to timeout.
   */
  public class TimedOutTestsListener extends RunListener {
  
    static final String TEST_TIMED_OUT_PREFIX = "test timed out after";
    
    private static String INDENT = "    ";
  
    private final PrintWriter output;
    
    public TimedOutTestsListener() {
      this.output = new PrintWriter(System.err);
    }
    
    public TimedOutTestsListener(PrintWriter output) {
      this.output = output;
    }
  
    @Override
    public void testFailure(Failure failure) throws Exception {
      if (failure != null && failure.getMessage() != null 
          && failure.getMessage().startsWith(TEST_TIMED_OUT_PREFIX)) {
        output.println("====> TEST TIMED OUT. PRINTING THREAD DUMP. <====");
        output.println();
        output.print(buildThreadDiagnosticString());
      }
    }
    
    public static String buildThreadDiagnosticString() {
      StringWriter sw = new StringWriter();
      PrintWriter output = new PrintWriter(sw);
      
      DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss,SSS");
      output.println(String.format("Timestamp: %s", dateFormat.format(new Date())));
      output.println();
      output.println(buildThreadDump());
      
      String deadlocksInfo = buildDeadlockInfo();
      if (deadlocksInfo != null) {
        output.println("====> DEADLOCKS DETECTED <====");
        output.println();
        output.println(deadlocksInfo);
      }
  
      return sw.toString();
    }
  
    static String buildThreadDump() {
      StringBuilder dump = new StringBuilder();
      Map<Thread, StackTraceElement[]> stackTraces = Thread.getAllStackTraces();
      for (Map.Entry<Thread, StackTraceElement[]> e : stackTraces.entrySet()) {
        Thread thread = e.getKey();
        dump.append(String.format(
            "\"%s\" %s prio=%d tid=%d %s\njava.lang.Thread.State: %s",
            thread.getName(),
            (thread.isDaemon() ? "daemon" : ""),
            thread.getPriority(),
            thread.getId(),
            Thread.State.WAITING.equals(thread.getState()) ? 
                "in Object.wait()" : thread.getState().name().toLowerCase(Locale.ROOT),
            Thread.State.WAITING.equals(thread.getState()) ? 
                "WAITING (on object monitor)" : thread.getState()));
       for (StackTraceElement stackTraceElement : e.getValue()) {
         dump.append("\n        at ");
         dump.append(stackTraceElement);
       }
       dump.append("\n");
     }
     return dump.toString();
   }
   
   static String buildDeadlockInfo() {
     ThreadMXBean threadBean = ManagementFactory.getThreadMXBean();
     long[] threadIds = threadBean.findMonitorDeadlockedThreads();
     if (threadIds != null && threadIds.length > 0) {
       StringWriter stringWriter = new StringWriter();
       PrintWriter out = new PrintWriter(stringWriter);
       
       ThreadInfo[] infos = threadBean.getThreadInfo(threadIds, true, true);
       for (ThreadInfo ti : infos) {
         printThreadInfo(ti, out);
         printLockInfo(ti.getLockedSynchronizers(), out);
         out.println();
       }
       
       out.close();
       return stringWriter.toString();
     } else {
       return null;
     }
   }
   
   private static void printThreadInfo(ThreadInfo ti, PrintWriter out) {
     // print thread information
     printThread(ti, out);
 
     // print stack trace with locks
     StackTraceElement[] stacktrace = ti.getStackTrace();
     MonitorInfo[] monitors = ti.getLockedMonitors();
     for (int i = 0; i < stacktrace.length; i++) {
       StackTraceElement ste = stacktrace[i];
       out.println(INDENT + "at " + ste.toString());
       for (MonitorInfo mi : monitors) {
         if (mi.getLockedStackDepth() == i) {
           out.println(INDENT + "  - locked " + mi);
         }
       }
     }
     out.println();
   }
 
   private static void printThread(ThreadInfo ti, PrintWriter out) {
     out.print("\"" + ti.getThreadName() + "\"" + " Id="
         + ti.getThreadId() + " in " + ti.getThreadState());
     if (ti.getLockName() != null) {
       out.print(" on lock=" + ti.getLockName());
     }
     if (ti.isSuspended()) {
       out.print(" (suspended)");
     }
     if (ti.isInNative()) {
       out.print(" (running in native)");
     }
     out.println();
     if (ti.getLockOwnerName() != null) {
       out.println(INDENT + " owned by " + ti.getLockOwnerName() + " Id="
           + ti.getLockOwnerId());
     }
   }
 
   private static void printLockInfo(LockInfo[] locks, PrintWriter out) {
     out.println(INDENT + "Locked synchronizers: count = " + locks.length);
     for (LockInfo li : locks) {
       out.println(INDENT + "  - " + li);
     }
     out.println();
   }
   
 }