package com.atlassian.httpclient.apache.httpcomponents;
   
   import com.atlassian.httpclient.api.EntityBuilder;
   import com.google.common.collect.Maps;
   import org.apache.http.Header;
   import org.apache.http.HttpEntity;
   import org.apache.http.entity.mime.MultipartEntity;
   
   import java.io.ByteArrayInputStream;
  import java.io.ByteArrayOutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.util.Map;
  
  /**
   * Builder for HttpEntities with multipart/form data.
   */
  public class MultiPartEntityBuilder implements EntityBuilder {
      private final HttpEntity apacheMultipartEntity;
  
      /**
       * @deprecated since 0.22. Use {@link #MultiPartEntityBuilder(org.apache.http.HttpEntity)} instead.
       */
      @Deprecated
      public MultiPartEntityBuilder(final MultipartEntity multipartEntity) {
          this.apacheMultipartEntity = multipartEntity;
      }
  
      /**
       * @since 0.22
       */
      public MultiPartEntityBuilder(final HttpEntity multipartEntity) {
          this.apacheMultipartEntity = multipartEntity;
      }
  
      private static class MultiPartEntity implements Entity {
          private final Map<String, String> headers;
          private final InputStream inputStream;
  
          public MultiPartEntity(Map<String, String> headers, InputStream inputStream) {
              this.headers = headers;
              this.inputStream = inputStream;
          }
  
          @Override
          public Map<String, String> getHeaders() {
              return this.headers;
          }
  
          @Override
          public InputStream getInputStream() {
              return this.inputStream;
          }
      }
  
      @Override
      public Entity build() {
          try {
              final ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
              apacheMultipartEntity.writeTo(outputStream);
              final InputStream inputStream = new ByteArrayInputStream(outputStream.toByteArray());
              final Header header = apacheMultipartEntity.getContentType();
              final Map<String, String> headers = Maps.newHashMap();
              headers.put(header.getName(), header.getValue());
              return new MultiPartEntity(headers, inputStream);
          } catch (IOException e) {
              throw new RuntimeException(e);
          }
      }
  }