/*
    *  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.mina.core.write;
  
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.LinkedHashMap;
  import java.util.List;
  import java.util.Set;
  
  import org.apache.mina.util.MapBackedSet;
  
  /**
   * An exception which is thrown when one or more write operations failed.
   *
   * @author <a href="http://mina.apache.org">Apache MINA Project</a>
   */
  public class WriteException extends IOException {
      /** The mandatory serialVersionUUID */
      private static final long serialVersionUID = -4174407422754524197L;
  
      /** The list of WriteRequest stored in this exception */
      private final List<WriteRequest> requests;
  
      /**
       * Creates a new WriteException instance.
       * 
       * @param request The associated {@link WriteRequest}
       */
      public WriteException(WriteRequest request) {
          super();
          this.requests = asRequestList(request);
      }
  
      /**
       * Creates a new WriteException instance.
       * 
       * @param request The associated {@link WriteRequest}
       * @param message The detail message
       */
      public WriteException(WriteRequest request, String message) {
          super(message);
          this.requests = asRequestList(request);
      }
  
      /**
       * Creates a new WriteException instance.
       * 
       * @param request The associated {@link WriteRequest}
       * @param message The detail message
       * @param cause The Exception's cause
       */
      public WriteException(WriteRequest request, String message, Throwable cause) {
          super(message);
          initCause(cause);
          this.requests = asRequestList(request);
      }
  
      /**
       * Creates a new WriteException instance.
       * 
       * @param request The associated {@link WriteRequest}
       * @param cause The Exception's cause
       */
      public WriteException(WriteRequest request, Throwable cause) {
          initCause(cause);
          this.requests = asRequestList(request);
      }
  
      /**
       * Creates a new WriteException instance.
       * 
       * @param requests The collection of {@link WriteRequest}s
       */
      public WriteException(Collection<WriteRequest> requests) {
          super();
          this.requests = asRequestList(requests);
      }
  
      /**
      * Creates a new WriteException instance.
      * 
      * @param requests The collection of {@link WriteRequest}s
      * @param message The detail message
      */
     public WriteException(Collection<WriteRequest> requests, String message) {
         super(message);
         this.requests = asRequestList(requests);
     }
 
     /**
      * Creates a new WriteException instance.
      * 
      * @param requests The collection of {@link WriteRequest}s
      * @param message The detail message
      * @param cause The Exception's cause
      */
     public WriteException(Collection<WriteRequest> requests, String message, Throwable cause) {
         super(message);
         initCause(cause);
         this.requests = asRequestList(requests);
     }
 
     /**
      * Creates a new WriteException instance.
      * 
      * @param requests The collection of {@link WriteRequest}s
      * @param cause The Exception's cause
      */
     public WriteException(Collection<WriteRequest> requests, Throwable cause) {
         initCause(cause);
         this.requests = asRequestList(requests);
     }
 
     /**
      * @return the list of the failed {@link WriteRequest}, in the order of occurrence.
      */
     public List<WriteRequest> getRequests() {
         return requests;
     }
 
     /**
      * @return the firstly failed {@link WriteRequest}. 
      */
     public WriteRequest getRequest() {
         return requests.get(0);
     }
 
     private static List<WriteRequest> asRequestList(Collection<WriteRequest> requests) {
         if (requests == null) {
             throw new IllegalArgumentException("requests");
         }
         
         if (requests.isEmpty()) {
             throw new IllegalArgumentException("requests is empty.");
         }
 
         // Create a list of requests removing duplicates.
         Set<WriteRequest> newRequests = new MapBackedSet<>(new LinkedHashMap<WriteRequest, Boolean>());
         
         for (WriteRequest r : requests) {
             newRequests.add(r.getOriginalRequest());
         }
 
         return Collections.unmodifiableList(new ArrayList<WriteRequest>(newRequests));
     }
 
     private static List<WriteRequest> asRequestList(WriteRequest request) {
         if (request == null) {
             throw new IllegalArgumentException("request");
         }
 
         List<WriteRequest> requests = new ArrayList<>(1);
         requests.add(request.getOriginalRequest());
         
         return Collections.unmodifiableList(requests);
     }
 }