package com.atlassian.plugins.rest.common.multipart.jersey;
   
   import com.atlassian.plugins.rest.common.multipart.MultipartConfig;
   import com.atlassian.plugins.rest.common.multipart.MultipartConfigClass;
   import com.atlassian.plugins.rest.common.multipart.MultipartForm;
   import com.atlassian.plugins.rest.common.multipart.fileupload.CommonsFileUploadMultipartHandler;
   import com.sun.jersey.core.provider.AbstractMessageReaderWriterProvider;
   import org.apache.commons.fileupload.RequestContext;
   
  import java.io.IOException;
  import java.io.InputStream;
  import java.lang.annotation.Annotation;
  import java.lang.reflect.Type;
  import javax.ws.rs.WebApplicationException;
  import javax.ws.rs.core.MediaType;
  import javax.ws.rs.core.MultivaluedMap;
  import javax.ws.rs.ext.MessageBodyReader;
  import javax.ws.rs.ext.Provider;
  
  /**
   * Reads a multipart form data object
   *
   * @since 2.4
   */
  @Provider
  public class MultipartFormMessageBodyReader implements MessageBodyReader<MultipartForm> {
      public boolean isReadable(final Class<?> type, final Type genericType, final Annotation[] annotations, final MediaType mediaType) {
          return type.equals(MultipartForm.class);
      }
  
      public MultipartForm readFrom(final Class<MultipartForm> type, final Type genericType,
                                    final Annotation[] annotations, final MediaType mediaType, final MultivaluedMap<String, String> httpHeaders,
                                    final InputStream entityStream)
              throws IOException, WebApplicationException {
          CommonsFileUploadMultipartHandler handler = getMultipartHandler(annotations);
          return handler.getForm(new RequestContext() {
              public String getCharacterEncoding() {
                  return AbstractMessageReaderWriterProvider.getCharset(mediaType).name();
              }
  
              public String getContentType() {
                  return mediaType.toString();
              }
  
              public int getContentLength() {
                  return -1;
              }
  
              public InputStream getInputStream() throws IOException {
                  return entityStream;
              }
          });
      }
  
      private CommonsFileUploadMultipartHandler getMultipartHandler(Annotation[] annotations) {
          for (Annotation annotation : annotations) {
              if (annotation instanceof MultipartConfigClass) {
                  Class<? extends MultipartConfig> configClass = ((MultipartConfigClass) annotation).value();
                  try {
                      MultipartConfig multipartConfig = configClass.newInstance();
                      return new CommonsFileUploadMultipartHandler(multipartConfig.getMaxFileSize(), multipartConfig.getMaxSize());
                  } catch (InstantiationException e) {
                      throw new RuntimeException(e);
                  } catch (IllegalAccessException e) {
                      throw new RuntimeException(e);
                  }
              }
          }
          return new CommonsFileUploadMultipartHandler(-1, -1);
      }
  }