/**
    *
    * 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.client;
  
  import java.io.IOException;
  import java.io.InterruptedIOException;
  import java.lang.reflect.UndeclaredThrowableException;
  import java.net.SocketTimeoutException;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.concurrent.atomic.AtomicBoolean;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.DoNotRetryIOException;
  import org.apache.hadoop.hbase.exceptions.PreemptiveFastFailException;
  import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
  import org.apache.hadoop.hbase.util.ExceptionUtil;
  import org.apache.hadoop.ipc.RemoteException;
  
  import com.google.protobuf.ServiceException;
  
  /**
   * Runs an rpc'ing {@link RetryingCallable}. Sets into rpc client
   * threadlocal outstanding timeouts as so we don't persist too much.
   * Dynamic rather than static so can set the generic appropriately.
   *
   * This object has a state. It should not be used by in parallel by different threads.
   * Reusing it is possible however, even between multiple threads. However, the user will
   *  have to manage the synchronization on its side: there is no synchronization inside the class.
   */
  @InterfaceAudience.Private
  public class RpcRetryingCaller<T> {
    public static final Log LOG = LogFactory.getLog(RpcRetryingCaller.class);
    /**
     * When we started making calls.
     */
    private long globalStartTime;
    /**
     * Start and end times for a single call.
     */
    private final static int MIN_RPC_TIMEOUT = 1;
    /** How many retries are allowed before we start to log */
    private final int startLogErrorsCnt;
  
    private final long pause;
    private final int retries;
    private final int rpcTimeout;// timeout for each rpc request
    private final AtomicBoolean cancelled = new AtomicBoolean(false);
    private final RetryingCallerInterceptor interceptor;
    private final RetryingCallerInterceptorContext context;
  
    public RpcRetryingCaller(long pause, int retries, int startLogErrorsCnt) {
      this(pause, retries, RetryingCallerInterceptorFactory.NO_OP_INTERCEPTOR, startLogErrorsCnt, 0);
    }
  
    public RpcRetryingCaller(long pause, int retries,
        RetryingCallerInterceptor interceptor, int startLogErrorsCnt, int rpcTimeout) {
      this.pause = pause;
      this.retries = retries;
      this.interceptor = interceptor;
      context = interceptor.createEmptyContext();
      this.startLogErrorsCnt = startLogErrorsCnt;
      this.rpcTimeout = rpcTimeout;
    }
  
    private int getRemainingTime(int callTimeout) {
      if (callTimeout <= 0) {
        return 0;
      } else {
        if (callTimeout == Integer.MAX_VALUE) return Integer.MAX_VALUE;
        int remainingTime = (int) (callTimeout -
            (EnvironmentEdgeManager.currentTime() - this.globalStartTime));
        if (remainingTime < MIN_RPC_TIMEOUT) {
          // If there is no time left, we're trying anyway. It's too late.
          // 0 means no timeout, and it's not the intent here. So we secure both cases by
          // resetting to the minimum.
          remainingTime = MIN_RPC_TIMEOUT;
        }
        return remainingTime;
      }
   }
 
   private int getTimeout(int callTimeout){
     int timeout = getRemainingTime(callTimeout);
     if (timeout <= 0 || rpcTimeout > 0 && rpcTimeout < timeout){
       timeout = rpcTimeout;
     }
     return timeout;
   }
 
   public void cancel(){
     synchronized (cancelled){
       cancelled.set(true);
       cancelled.notifyAll();
     }
   }
 
   /**
    * Retries if invocation fails.
    * @param callTimeout Timeout for this call
    * @param callable The {@link RetryingCallable} to run.
    * @return an object of type T
    * @throws IOException if a remote or network exception occurs
    * @throws RuntimeException other unspecified error
    */
   public T callWithRetries(RetryingCallable<T> callable, int callTimeout)
   throws IOException, RuntimeException {
     List<RetriesExhaustedException.ThrowableWithExtraContext> exceptions =
       new ArrayList<RetriesExhaustedException.ThrowableWithExtraContext>();
     this.globalStartTime = EnvironmentEdgeManager.currentTime();
     context.clear();
     for (int tries = 0;; tries++) {
       long expectedSleep;
       try {
         // bad cache entries are cleared in the call to RetryingCallable#throwable() in catch block
         callable.prepare(tries != 0); // if called with false, check table status on ZK
         interceptor.intercept(context.prepare(callable, tries));
         return callable.call(getTimeout(callTimeout));
       } catch (PreemptiveFastFailException e) {
         throw e;
       } catch (Throwable t) {
         ExceptionUtil.rethrowIfInterrupt(t);
 
         // translateException throws exception when should not retry: i.e. when request is bad.
         interceptor.handleFailure(context, t);
         t = translateException(t);
         if (tries > startLogErrorsCnt) {
           LOG.info("Call exception, tries=" + tries + ", retries=" + retries + ", started=" +
               (EnvironmentEdgeManager.currentTime() - this.globalStartTime) + " ms ago, "
               + "cancelled=" + cancelled.get() + ", msg="
               + t.getMessage() + " " + callable.getExceptionMessageAdditionalDetail());
         }
 
         callable.throwable(t, retries != 1);
         RetriesExhaustedException.ThrowableWithExtraContext qt =
             new RetriesExhaustedException.ThrowableWithExtraContext(t,
                 EnvironmentEdgeManager.currentTime(), toString());
         exceptions.add(qt);
         if (tries >= retries - 1) {
           throw new RetriesExhaustedException(tries, exceptions);
         }
         // If the server is dead, we need to wait a little before retrying, to give
         //  a chance to the regions to be
         // get right pause time, start by RETRY_BACKOFF[0] * pause
         expectedSleep = callable.sleep(pause, tries);
 
         // If, after the planned sleep, there won't be enough time left, we stop now.
         long duration = singleCallDuration(expectedSleep);
         if (duration > callTimeout) {
           String msg = "callTimeout=" + callTimeout + ", callDuration=" + duration +
               ": " + t.getMessage() + " " + callable.getExceptionMessageAdditionalDetail();
           throw (SocketTimeoutException)(new SocketTimeoutException(msg).initCause(t));
         }
       } finally {
         interceptor.updateFailureInfo(context);
       }
       try {
         if (expectedSleep > 0) {
           synchronized (cancelled) {
             if (cancelled.get()) return null;
             cancelled.wait(expectedSleep);
           }
         }
         if (cancelled.get()) return null;
       } catch (InterruptedException e) {
         throw new InterruptedIOException("Interrupted after " + tries + " tries  on " + retries);
       }
     }
   }
 
   /**
    * @return Calculate how long a single call took
    */
   private long singleCallDuration(final long expectedSleep) {
     return (EnvironmentEdgeManager.currentTime() - this.globalStartTime) + expectedSleep;
   }
 
   /**
    * Call the server once only.
    * {@link RetryingCallable} has a strange shape so we can do retrys.  Use this invocation if you
    * want to do a single call only (A call to {@link RetryingCallable#call(int)} will not likely
    * succeed).
    * @return an object of type T
    * @throws IOException if a remote or network exception occurs
    * @throws RuntimeException other unspecified error
    */
   public T callWithoutRetries(RetryingCallable<T> callable, int callTimeout)
   throws IOException, RuntimeException {
     // The code of this method should be shared with withRetries.
     this.globalStartTime = EnvironmentEdgeManager.currentTime();
     try {
       callable.prepare(false);
       return callable.call(callTimeout);
     } catch (Throwable t) {
       Throwable t2 = translateException(t);
       ExceptionUtil.rethrowIfInterrupt(t2);
       // It would be nice to clear the location cache here.
       if (t2 instanceof IOException) {
         throw (IOException)t2;
       } else {
         throw new RuntimeException(t2);
       }
     }
   }
 
   /**
    * Get the good or the remote exception if any, throws the DoNotRetryIOException.
    * @param t the throwable to analyze
    * @return the translated exception, if it's not a DoNotRetryIOException
    * @throws DoNotRetryIOException - if we find it, we throw it instead of translating.
    */
   static Throwable translateException(Throwable t) throws DoNotRetryIOException {
     if (t instanceof UndeclaredThrowableException) {
       if (t.getCause() != null) {
         t = t.getCause();
       }
     }
     if (t instanceof RemoteException) {
       t = ((RemoteException)t).unwrapRemoteException();
     }
     if (t instanceof LinkageError) {
       throw new DoNotRetryIOException(t);
     }
     if (t instanceof ServiceException) {
       ServiceException se = (ServiceException)t;
       Throwable cause = se.getCause();
       if (cause != null) {
         if (cause instanceof DoNotRetryIOException) {
           throw (DoNotRetryIOException)cause;
         } else if (cause instanceof NeedUnmanagedConnectionException) {
           throw new DoNotRetryIOException(cause);
         }
       }
       // Don't let ServiceException out; its rpc specific.
       t = cause;
       // t could be a RemoteException so go aaround again.
       translateException(t);
     } else if (t instanceof DoNotRetryIOException) {
       throw (DoNotRetryIOException)t;
     } else if (t instanceof NeedUnmanagedConnectionException) {
       throw new DoNotRetryIOException(t);
     }
     return t;
   }
 
   @Override
   public String toString() {
     return "RpcRetryingCaller{" + "globalStartTime=" + globalStartTime +
         ", pause=" + pause + ", retries=" + retries + '}';
   }
 }