/*
    * Copyright 2012 The Netty Project
    *
    * The Netty Project 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 io.netty.handler.codec.http.multipart;
  
  import io.netty.handler.codec.http.HttpRequest;
  import io.netty.util.internal.PlatformDependent;
  
  import java.io.IOException;
  import java.nio.charset.Charset;
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  import java.util.Map.Entry;
  
  /**
   * Default factory giving Attribute and FileUpload according to constructor
   *
   * Attribute and FileUpload could be :<br>
   * - MemoryAttribute, DiskAttribute or MixedAttribute<br>
   * - MemoryFileUpload, DiskFileUpload or MixedFileUpload<br>
   * according to the constructor.
   */
  public class DefaultHttpDataFactory implements HttpDataFactory {
      /**
       * Proposed default MINSIZE as 16 KB.
       */
      public static final long MINSIZE = 0x4000;
  
      private final boolean useDisk;
  
      private final boolean checkSize;
  
      private long minSize;
  
      /**
       * Keep all HttpDatas until cleanAllHttpDatas() is called.
       */
      private final Map<HttpRequest, List<HttpData>> requestFileDeleteMap = PlatformDependent.newConcurrentHashMap();
  
      /**
       * HttpData will be in memory if less than default size (16KB).
       * The type will be Mixed.
       */
      public DefaultHttpDataFactory() {
          useDisk = false;
          checkSize = true;
          minSize = MINSIZE;
      }
  
      /**
       * HttpData will be always on Disk if useDisk is True, else always in Memory if False
       */
      public DefaultHttpDataFactory(boolean useDisk) {
          this.useDisk = useDisk;
          checkSize = false;
      }
  
      /**
       * HttpData will be on Disk if the size of the file is greater than minSize, else it
       * will be in memory. The type will be Mixed.
       */
      public DefaultHttpDataFactory(long minSize) {
          useDisk = false;
          checkSize = true;
          this.minSize = minSize;
      }
  
      /**
       * @return the associated list of Files for the request
       */
      private List<HttpData> getList(HttpRequest request) {
          List<HttpData> list = requestFileDeleteMap.get(request);
          if (list == null) {
              list = new ArrayList<HttpData>();
              requestFileDeleteMap.put(request, list);
          }
          return list;
      }
  
      @Override
      public Attribute createAttribute(HttpRequest request, String name) {
          if (useDisk) {
              Attribute attribute = new DiskAttribute(name);
              List<HttpData> fileToDelete = getList(request);
              fileToDelete.add(attribute);
             return attribute;
         }
         if (checkSize) {
             Attribute attribute = new MixedAttribute(name, minSize);
             List<HttpData> fileToDelete = getList(request);
             fileToDelete.add(attribute);
             return attribute;
         }
         return new MemoryAttribute(name);
     }
 
     @Override
     public Attribute createAttribute(HttpRequest request, String name, String value) {
         if (useDisk) {
             Attribute attribute;
             try {
                 attribute = new DiskAttribute(name, value);
             } catch (IOException e) {
                 // revert to Mixed mode
                 attribute = new MixedAttribute(name, value, minSize);
             }
             List<HttpData> fileToDelete = getList(request);
             fileToDelete.add(attribute);
             return attribute;
         }
         if (checkSize) {
             Attribute attribute = new MixedAttribute(name, value, minSize);
             List<HttpData> fileToDelete = getList(request);
             fileToDelete.add(attribute);
             return attribute;
         }
         try {
             return new MemoryAttribute(name, value);
         } catch (IOException e) {
             throw new IllegalArgumentException(e);
         }
     }
 
     @Override
     public FileUpload createFileUpload(HttpRequest request, String name, String filename,
             String contentType, String contentTransferEncoding, Charset charset,
             long size) {
         if (useDisk) {
             FileUpload fileUpload = new DiskFileUpload(name, filename, contentType,
                     contentTransferEncoding, charset, size);
             List<HttpData> fileToDelete = getList(request);
             fileToDelete.add(fileUpload);
             return fileUpload;
         }
         if (checkSize) {
             FileUpload fileUpload = new MixedFileUpload(name, filename, contentType,
                     contentTransferEncoding, charset, size, minSize);
             List<HttpData> fileToDelete = getList(request);
             fileToDelete.add(fileUpload);
             return fileUpload;
         }
         return new MemoryFileUpload(name, filename, contentType,
                 contentTransferEncoding, charset, size);
     }
 
     @Override
     public void removeHttpDataFromClean(HttpRequest request, InterfaceHttpData data) {
         if (data instanceof HttpData) {
             List<HttpData> fileToDelete = getList(request);
             fileToDelete.remove(data);
         }
     }
 
     @Override
     public void cleanRequestHttpDatas(HttpRequest request) {
         List<HttpData> fileToDelete = requestFileDeleteMap.remove(request);
         if (fileToDelete != null) {
             for (HttpData data: fileToDelete) {
                 data.delete();
             }
             fileToDelete.clear();
         }
     }
 
     @Override
     public void cleanAllHttpDatas() {
         Iterator<Entry<HttpRequest, List<HttpData>>> i = requestFileDeleteMap.entrySet().iterator();
         while (i.hasNext()) {
             Entry<HttpRequest, List<HttpData>> e = i.next();
             i.remove();
 
             List<HttpData> fileToDelete = e.getValue();
             if (fileToDelete != null) {
                 for (HttpData data : fileToDelete) {
                     data.delete();
                 }
                 fileToDelete.clear();
             }
         }
     }
 }