package org.jboss.resteasy.plugins.providers.multipart;

import javax.ws.rs.core.MediaType;

/**
 * Represents a multipart/related (RFC2387) outgoing mime message. A
 * multipart/related message is used to hold a root or start part and other
 * parts which are referenced from the root part. All parts have a unique id.
 * The type and the id of the start part is presented in parameters in the
 * message content-type header.
 *
 * Usage is the same as with {@link MultipartOutput}:
 *
 * <code>
 * MultipartRelatedDataOutput mrdo = new MultipartRelatedDataOutput();
 * mrdo.addPart(...);
 * </code>
 *
 * The first added part will be used as root. The root parts content-type will
 * be used as the type parameter of the content-type of the mime message.
 *
 * For parts without Content-ID header a unique id will be generated during
 * serialization.
 *
 * @author Attila Kiraly
 * @version $Revision: 1 $
 */
public class MultipartRelatedOutput extends MultipartOutput {
   private String startInfo;

   /**
    * The part that will be used as the root.
    *
    * @return the first in the list of added parts.
    */
   public OutputPart getRootPart() {
      return getParts().get(0);
   }

   /**
    * Used to add parts to the multipart output message.
    *
    * @param entity
    *            the object representing the part's body
    * @param mediaType
    *            the Content-Type of the part
    * @param contentId
    *            the Content-ID to be used as identification for the current
    *            part, optional, if null one will be generated
    * @param contentTransferEncoding
    *            The value to be used for the Content-Transfer-Encoding header
    *            field of the part. It's optional, if you don't want to set
    *            this pass null. Example values are: "7bit",
    *            "quoted-printable", "base64", "8bit", "binary"
    * @return {@link OutputPart}
    */
   public OutputPart addPart(Object entity, MediaType mediaType,
         String contentId, String contentTransferEncoding) {
      OutputPart outputPart = super.addPart(entity, mediaType);
      if (contentTransferEncoding != null)
         outputPart.getHeaders().putSingle("Content-Transfer-Encoding",
               contentTransferEncoding);
      if (contentId != null)
         outputPart.getHeaders().putSingle("Content-ID", contentId);
      return outputPart;
   }

   /**
    * Returns the start-info parameter of the Content-Type. This is an optional
    * parameter.
    *
    * As described in RFC2387:
    *
    * 3.3. The Start-Info Parameter
    *
    * Additional information can be provided to an application by the
    * start-info parameter. It contains either a string or points, via a
    * content-ID, to another MIME entity in the message. A typical use might be
    * to provide additional command line parameters or a MIME entity giving
    * auxiliary information for processing the compound object.
    *
    * Applications that use Multipart/Related must specify the interpretation
    * of start-info. User Agents shall provide the parameter's value to the
    * processing application. Processes can distinguish a start-info reference
    * from a token or quoted-string by examining the first non-white-space
    * character, "&gt;" indicates a reference.
    *
    * @return the currently configured start-info
    */
   public String getStartInfo() {
      return startInfo;
   }

   /**
    * Sets the start-info parameter of the Content-Type. This is an optional
    * parameter.
    *
    * As described in RFC2387:
    *
    * 3.3. The Start-Info Parameter
    *
    * Additional information can be provided to an application by the
    * start-info parameter. It contains either a string or points, via a
    * content-ID, to another MIME entity in the message. A typical use might be
    * to provide additional command line parameters or a MIME entity giving
    * auxiliary information for processing the compound object.
    *
    * Applications that use Multipart/Related must specify the interpretation
    * of start-info. User Agents shall provide the parameter's value to the
    * processing application. Processes can distinguish a start-info reference
    * from a token or quoted-string by examining the first non-white-space
    * character, "&gt;" indicates a reference.
    *
    * @param startInfo the value to be set
    */
   public void setStartInfo(String startInfo) {
      this.startInfo = startInfo;
   }
}
