content: /*
   * Copyright (c) 2013. wyouflf (wyouflf@gmail.com)
   *
   * Licensed 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 com.lidroid.xutils.http.client.multipart;
  
  import com.lidroid.xutils.http.client.multipart.content.ContentBody;
  
  /**
   * FormBodyPart class represents a content body that can be used as a part of multipart encoded
   * entities. This class automatically populates the header with standard fields based on
   * the content description of the enclosed body.
   *
   * @since 4.0
   */
  public class FormBodyPart {
  
      private final String name;
      private final MinimalFieldHeader header;
  
      private final ContentBody body;
  
      public FormBodyPart(final String name, final ContentBody body) {
          super();
          if (name == null) {
              throw new IllegalArgumentException("Name may not be null");
          }
          if (body == null) {
              throw new IllegalArgumentException("Body may not be null");
          }
          this.name = name;
          this.body = body;
          this.header = new MinimalFieldHeader();
  
          generateContentDisposition(body);
          generateContentType(body);
          generateTransferEncoding(body);
      }
  
      public FormBodyPart(final String name, final ContentBody body, final String contentDisposition) {
          super();
          if (name == null) {
              throw new IllegalArgumentException("Name may not be null");
          }
          if (body == null) {
              throw new IllegalArgumentException("Body may not be null");
          }
          this.name = name;
          this.body = body;
          this.header = new MinimalFieldHeader();
  
          if (contentDisposition != null) {
              addField(MIME.CONTENT_DISPOSITION, contentDisposition);
          } else {
              generateContentDisposition(body);
          }
          generateContentType(body);
          generateTransferEncoding(body);
      }
  
      public String getName() {
          return this.name;
      }
  
      public ContentBody getBody() {
          return this.body;
      }
  
      public MinimalFieldHeader getHeader() {
          return this.header;
      }
  
      public void addField(final String name, final String value) {
          if (name == null) {
              throw new IllegalArgumentException("Field name may not be null");
          }
          this.header.addField(new MinimalField(name, value));
      }
  
      protected void generateContentDisposition(final ContentBody body) {
          StringBuilder buffer = new StringBuilder();
          buffer.append("form-data; name=\"");
          buffer.append(getName());
          buffer.append("\"");
          if (body.getFilename() != null) {
              buffer.append("; filename=\"");
              buffer.append(body.getFilename());
              buffer.append("\"");
          }
          addField(MIME.CONTENT_DISPOSITION, buffer.toString());
      }
  
      protected void generateContentType(final ContentBody body) {
          StringBuilder buffer = new StringBuilder();
          buffer.append(body.getMimeType()); // MimeType cannot be null
          if (body.getCharset() != null) { // charset may legitimately be null
              buffer.append("; charset=");
              buffer.append(body.getCharset());
          }
          addField(MIME.CONTENT_TYPE, buffer.toString());
      }
  
      protected void generateTransferEncoding(final ContentBody body) {
          addField(MIME.CONTENT_TRANSFER_ENC, body.getTransferEncoding()); // TE cannot be null
      }
  
  }
  