/**
    * 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.ipc;
  
  import com.google.protobuf.Descriptors;
  import com.google.protobuf.Message;
  import org.apache.hadoop.hbase.CellScanner;
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
  import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
  
  import java.io.IOException;
  
  /** A call waiting for a value. */
  @InterfaceAudience.Private
  public class Call {
    final int id;                                 // call id
    final Message param;                          // rpc request method param object
    /**
     * Optionally has cells when making call.  Optionally has cells set on response.  Used
     * passing cells to the rpc and receiving the response.
     */
    CellScanner cells;
    Message response;                             // value, null if error
    // The return type.  Used to create shell into which we deserialize the response if any.
    Message responseDefaultType;
    IOException error;                            // exception, null if value
    volatile boolean done;                                 // true when call is done
    long startTime;
    final Descriptors.MethodDescriptor md;
    final int timeout; // timeout in millisecond for this call; 0 means infinite.
  
    protected Call(int id, final Descriptors.MethodDescriptor md, Message param,
        final CellScanner cells, final Message responseDefaultType, int timeout) {
      this.param = param;
      this.md = md;
      this.cells = cells;
      this.startTime = EnvironmentEdgeManager.currentTime();
      this.responseDefaultType = responseDefaultType;
      this.id = id;
      this.timeout = timeout;
    }
  
    /**
     * Check if the call did timeout. Set an exception (includes a notify) if it's the case.
     * @return true if the call is on timeout, false otherwise.
     */
    public boolean checkAndSetTimeout() {
      if (timeout == 0){
        return false;
      }
  
      long waitTime = EnvironmentEdgeManager.currentTime() - getStartTime();
      if (waitTime >= timeout) {
        IOException ie = new CallTimeoutException("Call id=" + id +
            ", waitTime=" + waitTime + ", operationTimeout=" + timeout + " expired.");
        setException(ie); // includes a notify
        return true;
      } else {
        return false;
      }
    }
  
    public int remainingTime() {
      if (timeout == 0) {
        return Integer.MAX_VALUE;
      }
  
      int remaining = timeout - (int) (EnvironmentEdgeManager.currentTime() - getStartTime());
      return remaining > 0 ? remaining : 0;
    }
  
    @Override
    public String toString() {
      return "callId: " + this.id + " methodName: " + this.md.getName() + " param {" +
        (this.param != null? ProtobufUtil.getShortTextFormat(this.param): "") + "}";
    }
  
    /** Indicate when the call is complete and the
     * value or error are available.  Notifies by default.  */
    protected synchronized void callComplete() {
      this.done = true;
      notify();                                 // notify caller
    }
 
   /** Set the exception when there is an error.
    * Notify the caller the call is done.
    *
    * @param error exception thrown by the call; either local or remote
    */
   public void setException(IOException error) {
     this.error = error;
     callComplete();
   }
 
   /**
    * Set the return value when there is no error.
    * Notify the caller the call is done.
    *
    * @param response return value of the call.
    * @param cells Can be null
    */
   public void setResponse(Message response, final CellScanner cells) {
     this.response = response;
     this.cells = cells;
     callComplete();
   }
 
   public long getStartTime() {
     return this.startTime;
   }
 }