/*
    * Copyright 2022 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:
    *
    *   https://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.buffer.ByteBuf;
  import io.netty.util.AbstractReferenceCounted;
  
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStream;
  import java.nio.charset.Charset;
  
  abstract class AbstractMixedHttpData<D extends HttpData> extends AbstractReferenceCounted implements HttpData {
      final String baseDir;
      final boolean deleteOnExit;
      D wrapped;
  
      private final long limitSize;
  
      AbstractMixedHttpData(long limitSize, String baseDir, boolean deleteOnExit, D initial) {
          this.limitSize = limitSize;
          this.wrapped = initial;
          this.baseDir = baseDir;
          this.deleteOnExit = deleteOnExit;
      }
  
      abstract D makeDiskData();
  
      @Override
      public long getMaxSize() {
          return wrapped.getMaxSize();
      }
  
      @Override
      public void setMaxSize(long maxSize) {
          wrapped.setMaxSize(maxSize);
      }
  
      @Override
      public ByteBuf content() {
          return wrapped.content();
      }
  
      @Override
      public void checkSize(long newSize) throws IOException {
          wrapped.checkSize(newSize);
      }
  
      @Override
      public long definedLength() {
          return wrapped.definedLength();
      }
  
      @Override
      public Charset getCharset() {
          return wrapped.getCharset();
      }
  
      @Override
      public String getName() {
          return wrapped.getName();
      }
  
      @Override
      public void addContent(ByteBuf buffer, boolean last) throws IOException {
          if (wrapped instanceof AbstractMemoryHttpData) {
              try {
                  checkSize(wrapped.length() + buffer.readableBytes());
                  if (wrapped.length() + buffer.readableBytes() > limitSize) {
                      D diskData = makeDiskData();
                      ByteBuf data = ((AbstractMemoryHttpData) wrapped).getByteBuf();
                      if (data != null && data.isReadable()) {
                          diskData.addContent(data.retain(), false);
                      }
                      wrapped.release();
                      wrapped = diskData;
                  }
              } catch (IOException e) {
                  buffer.release();
                  throw e;
              }
          }
          wrapped.addContent(buffer, last);
      }
  
      @Override
     protected void deallocate() {
         delete();
     }
 
     @Override
     public void delete() {
         wrapped.delete();
     }
 
     @Override
     public byte[] get() throws IOException {
         return wrapped.get();
     }
 
     @Override
     public ByteBuf getByteBuf() throws IOException {
         return wrapped.getByteBuf();
     }
 
     @Override
     public String getString() throws IOException {
         return wrapped.getString();
     }
 
     @Override
     public String getString(Charset encoding) throws IOException {
         return wrapped.getString(encoding);
     }
 
     @Override
     public boolean isInMemory() {
         return wrapped.isInMemory();
     }
 
     @Override
     public long length() {
         return wrapped.length();
     }
 
     @Override
     public boolean renameTo(File dest) throws IOException {
         return wrapped.renameTo(dest);
     }
 
     @Override
     public void setCharset(Charset charset) {
         wrapped.setCharset(charset);
     }
 
     @Override
     public void setContent(ByteBuf buffer) throws IOException {
         try {
             checkSize(buffer.readableBytes());
         } catch (IOException e) {
             buffer.release();
             throw e;
         }
         if (buffer.readableBytes() > limitSize) {
             if (wrapped instanceof AbstractMemoryHttpData) {
                 // change to Disk
                 wrapped.release();
                 wrapped = makeDiskData();
             }
         }
         wrapped.setContent(buffer);
     }
 
     @Override
     public void setContent(File file) throws IOException {
         checkSize(file.length());
         if (file.length() > limitSize) {
             if (wrapped instanceof AbstractMemoryHttpData) {
                 // change to Disk
                 wrapped.release();
                 wrapped = makeDiskData();
             }
         }
         wrapped.setContent(file);
     }
 
     @Override
     public void setContent(InputStream inputStream) throws IOException {
         if (wrapped instanceof AbstractMemoryHttpData) {
             // change to Disk even if we don't know the size
             wrapped.release();
             wrapped = makeDiskData();
         }
         wrapped.setContent(inputStream);
     }
 
     @Override
     public boolean isCompleted() {
         return wrapped.isCompleted();
     }
 
     @Override
     public HttpDataType getHttpDataType() {
         return wrapped.getHttpDataType();
     }
 
     @Override
     public int hashCode() {
         return wrapped.hashCode();
     }
 
     @Override
     public boolean equals(Object obj) {
         return wrapped.equals(obj);
     }
 
     @Override
     public int compareTo(InterfaceHttpData o) {
         return wrapped.compareTo(o);
     }
 
     @Override
     public String toString() {
         return "Mixed: " + wrapped;
     }
 
     @Override
     public ByteBuf getChunk(int length) throws IOException {
         return wrapped.getChunk(length);
     }
 
     @Override
     public File getFile() throws IOException {
         return wrapped.getFile();
     }
 
     @SuppressWarnings("unchecked")
     @Override
     public D copy() {
         return (D) wrapped.copy();
     }
 
     @SuppressWarnings("unchecked")
     @Override
     public D duplicate() {
         return (D) wrapped.duplicate();
     }
 
     @SuppressWarnings("unchecked")
     @Override
     public D retainedDuplicate() {
         return (D) wrapped.retainedDuplicate();
     }
 
     @SuppressWarnings("unchecked")
     @Override
     public D replace(ByteBuf content) {
         return (D) wrapped.replace(content);
     }
 
     @SuppressWarnings("unchecked")
     @Override
     public D touch() {
         wrapped.touch();
         return (D) this;
     }
 
     @SuppressWarnings("unchecked")
     @Override
     public D touch(Object hint) {
         wrapped.touch(hint);
         return (D) this;
     }
 
     @SuppressWarnings("unchecked")
     @Override
     public D retain() {
         return (D) super.retain();
     }
 
     @SuppressWarnings("unchecked")
     @Override
     public D retain(int increment) {
         return (D) super.retain(increment);
     }
 }