/**
  * Creates a {@link HttpPostRequestEncoder} that encodes the given {@code request} and {@code
  * blobContent}.
  *
  * @param request the {@link HttpRequest} containing headers and other metadata about the request.
  * @param blobContent the {@link ByteBuffer} that represents the content of the blob.
  * @param usermetadata the {@link ByteBuffer} that represents user metadata
  * @return a {@link HttpPostRequestEncoder} that can encode the {@code request} and {@code
  *     blobContent}.
  * @throws HttpPostRequestEncoder.ErrorDataEncoderException
  * @throws IOException
  */
 private HttpPostRequestEncoder createEncoder(
     HttpRequest request, ByteBuffer blobContent, ByteBuffer usermetadata)
     throws HttpPostRequestEncoder.ErrorDataEncoderException, IOException {
   HttpDataFactory httpDataFactory = new DefaultHttpDataFactory(false);
   HttpPostRequestEncoder encoder = new HttpPostRequestEncoder(httpDataFactory, request, true);
   FileUpload fileUpload =
       new MemoryFileUpload(
           RestUtils.MultipartPost.BLOB_PART,
           RestUtils.MultipartPost.BLOB_PART,
           "application/octet-stream",
           "",
           Charset.forName("UTF-8"),
           blobContent.remaining());
   fileUpload.setContent(Unpooled.wrappedBuffer(blobContent));
   encoder.addBodyHttpData(fileUpload);
   fileUpload =
       new MemoryFileUpload(
           RestUtils.MultipartPost.USER_METADATA_PART,
           RestUtils.MultipartPost.USER_METADATA_PART,
           "application/octet-stream",
           "",
           Charset.forName("UTF-8"),
           usermetadata.remaining());
   fileUpload.setContent(Unpooled.wrappedBuffer(usermetadata));
   encoder.addBodyHttpData(fileUpload);
   return encoder;
 }
 /** Example of reading request by chunk and getting values from chunk to chunk */
 private void readHttpDataChunkByChunk() {
   try {
     while (decoder.hasNext()) {
       InterfaceHttpData data = decoder.next();
       if (data != null) {
         // check if current HttpData is a FileUpload and previously set as partial
         if (partialContent == data) {
           logger.info(" 100% (FinalSize: " + partialContent.length() + ")");
           partialContent = null;
         }
         try {
           // new value
           writeHttpData(data);
         } finally {
           data.release();
         }
       }
     }
     // Check partial decoding for a FileUpload
     InterfaceHttpData data = decoder.currentPartialHttpData();
     if (data != null) {
       StringBuilder builder = new StringBuilder();
       if (partialContent == null) {
         partialContent = (HttpData) data;
         if (partialContent instanceof FileUpload) {
           builder
               .append("Start FileUpload: ")
               .append(((FileUpload) partialContent).getFilename())
               .append(" ");
         } else {
           builder.append("Start Attribute: ").append(partialContent.getName()).append(" ");
         }
         builder.append("(DefinedSize: ").append(partialContent.definedLength()).append(")");
       }
       if (partialContent.definedLength() > 0) {
         builder
             .append(" ")
             .append(partialContent.length() * 100 / partialContent.definedLength())
             .append("% ");
         logger.info(builder.toString());
       } else {
         builder.append(" ").append(partialContent.length()).append(" ");
         logger.info(builder.toString());
       }
     }
   } catch (EndOfDataDecoderException e1) {
     // end
     responseContent.append("\r\n\r\nEND OF CONTENT CHUNK BY CHUNK\r\n\r\n");
   }
 }
 private void writeHttpData(InterfaceHttpData data) {
   if (data.getHttpDataType() == HttpDataType.Attribute) {
     Attribute attribute = (Attribute) data;
     String value;
     try {
       value = attribute.getValue();
     } catch (IOException e1) {
       // Error while reading data from File, only print name and error
       e1.printStackTrace();
       responseContent.append(
           "\r\nBODY Attribute: "
               + attribute.getHttpDataType().name()
               + ": "
               + attribute.getName()
               + " Error while reading value: "
               + e1.getMessage()
               + "\r\n");
       return;
     }
     if (value.length() > 100) {
       responseContent.append(
           "\r\nBODY Attribute: "
               + attribute.getHttpDataType().name()
               + ": "
               + attribute.getName()
               + " data too long\r\n");
     } else {
       responseContent.append(
           "\r\nBODY Attribute: "
               + attribute.getHttpDataType().name()
               + ": "
               + attribute
               + "\r\n");
     }
   } else {
     responseContent.append(
         "\r\nBODY FileUpload: " + data.getHttpDataType().name() + ": " + data + "\r\n");
     if (data.getHttpDataType() == HttpDataType.FileUpload) {
       FileUpload fileUpload = (FileUpload) data;
       if (fileUpload.isCompleted()) {
         if (fileUpload.length() < 10000) {
           responseContent.append("\tContent of file\r\n");
           try {
             responseContent.append(fileUpload.getString(fileUpload.getCharset()));
           } catch (IOException e1) {
             // do nothing for the example
             e1.printStackTrace();
           }
           responseContent.append("\r\n");
         } else {
           responseContent.append(
               "\tFile too long to be printed out:" + fileUpload.length() + "\r\n");
         }
         // fileUpload.isInMemory();// tells if the file is in Memory
         // or on File
         // fileUpload.renameTo(dest); // enable to move into another
         // File dest
         // decoder.removeFileUploadFromClean(fileUpload); //remove
         // the File of to delete file
       } else {
         responseContent.append("\tFile to be continued but should not!\r\n");
       }
     }
   }
 }
  @Override
  public void channelRead0(ChannelHandlerContext ctx, HttpObject msg) throws Exception {
    try {
      if (msg instanceof FullHttpRequest) {
        FullHttpRequest fullRequest = (FullHttpRequest) msg;
        if (fullRequest.getUri().startsWith("/kctupload")) {

          if (fullRequest.getMethod().equals(HttpMethod.GET)) {
            // HTTP Get request!
            // Write the HTML page with the form
            writeMenu(ctx);
          } else if (fullRequest.getMethod().equals(HttpMethod.POST)) {
            /*
                 * HTTP Post request! Handle the uploaded form
                 * HTTP parameters:

            /kctupload
            username (should match player's Minecraft name)
            language (java, python, etc)
            jsonfile (a file upload, or empty)
            sourcefile (a file upload, or empty)
            jsontext (a JSON string, or empty)
            sourcetext (code as a String, or empty)
                 */

            String language = null;
            String playerName = null;
            String client = null;
            String jsonText = null;
            String sourceText = null;
            Map<String, UploadedFile> files = new LinkedHashMap<String, UploadedFile>();

            HttpPostRequestDecoder decoder = new HttpPostRequestDecoder(fullRequest);
            try {
              logger.trace("is multipart? " + decoder.isMultipart());
              while (decoder.hasNext()) {
                InterfaceHttpData data = decoder.next();
                if (data == null) continue;

                try {
                  if (data.getHttpDataType() == HttpDataType.Attribute) {
                    Attribute attribute = (Attribute) data;
                    String name = attribute.getName();
                    String value = attribute.getValue();
                    logger.trace(String.format("http attribute: %s => %s", name, value));
                    if (name.equals("language")) {
                      language = value;
                    } else if (name.equals("playerName")) {
                      playerName = value;
                    } else if (name.equals("client")) {
                      client = value;
                    } else if (name.equals("jsontext")) {
                      jsonText = value;
                    } else if (name.equals("sourcetext")) {
                      sourceText = value;
                    } else {
                      logger.warn(
                          String.format("Unknown kctupload attribute: %s => %s", name, value));
                    }
                  } else if (data.getHttpDataType() == HttpDataType.FileUpload) {
                    // Handle file upload
                    // We may have json, source, or both
                    FileUpload fileUpload = (FileUpload) data;
                    logger.debug(
                        String.format(
                            "http file upload name %s, filename: ",
                            data.getName(), fileUpload.getFilename()));
                    String filename = fileUpload.getFilename();
                    ByteBuf buf = fileUpload.getByteBuf();
                    String fileBody = new String(buf.array(), "UTF-8");
                    files.put(data.getName(), new UploadedFile(filename, fileBody));
                  }
                } finally {
                  data.release();
                }
              }
            } finally {
              if (decoder != null) {
                // clean up resources
                decoder.cleanFiles();
                decoder.destroy();
              }
            }

            /*
             * Error checking here makes the most sense, since we can send back a reasonable error message
             * to the uploading client at this point. Makes less sense to wait to compile.
             *
             * Upload possibilities:
             *
             * bluej: file1, file2, etc. All source code. Language should be set to Java.
             * Convert to JSON, then to KCTScript. Signal an error if one happens.
             *
             * web: jsontext and/or sourcetext. json-only is OK; source-only is OK if it's Java.
             * Cannot send source-only for non-Java languages, since we can't build them (yet).
             *
             * anything else: convert to Json and hope for the best
             */
            try {
              KCTUploadHook hook = new KCTUploadHook();
              StringBuilder res = new StringBuilder();

              if (playerName == null || playerName.equals("")) {
                // XXX How do we know that the playerName is valid?
                // TODO: authenticate against Mojang's server?
                throw new TurtleException("You must specify your MineCraft player name!");
              }

              if (client == null) {
                throw new TurtleException(
                    "Your uploading and submission system must specify "
                        + "the type of client used for the upload (i.e. bluej, web, pykc, etc)");
              }

              hook.setPlayerName(playerName);
              res.append(
                  String.format("Hello %s! Thanks for using KnoxCraft Turtles\n\n", playerName));

              TurtleCompiler turtleCompiler = new TurtleCompiler(logger);
              int success = 0;
              int failure = 0;
              if (client.equalsIgnoreCase("web")
                  || client.equalsIgnoreCase("testclient")
                  || client.startsWith("pykc")) {
                // WEB OR PYTHON UPLOAD
                logger.trace("Upload from web");
                // must have both Json and source, either in text area or as uploaded files
                // XXX Conlfict of comments of the top and here??? What do we need both/ only JSon?
                // Is there a want we want, thus forcing it
                if (sourceText != null && jsonText != null) {
                  KCTScript script = turtleCompiler.parseFromJson(jsonText);
                  script.setLanguage(language);
                  script.setSourceCode(sourceText);
                  res.append(
                      String.format(
                          "Successfully uploaded KnoxCraft Turtle program "
                              + "named %s, in programming language %s\n",
                          script.getScriptName(), script.getLanguage()));
                  success++;
                  hook.addScript(script);
                } else if (files.containsKey("jsonfile") && files.containsKey("sourcefile")) {
                  UploadedFile sourceUpload = files.get("sourcefile");
                  UploadedFile jsonUpload = files.get("jsonfile");
                  KCTScript script = turtleCompiler.parseFromJson(jsonUpload.body);
                  script.setLanguage(language);
                  script.setSourceCode(sourceUpload.body);
                  res.append(
                      String.format(
                          "Successfully uploaded KnoxCraft Turtle program "
                              + "named %s, in programming language %s\n",
                          script.getScriptName(), script.getLanguage()));
                  success++;
                  hook.addScript(script);
                } else {
                  throw new TurtleException(
                      "You must upload BOTH json and the corresponding source code "
                          + " (either as files or pasted into the text areas)");
                }
              } else if ("bluej".equalsIgnoreCase(client)) {
                // BLUEJ UPLOAD
                logger.trace("Upload from bluej");
                for (Entry<String, UploadedFile> entry : files.entrySet()) {
                  try {
                    UploadedFile uploadedFile = entry.getValue();
                    res.append(
                        String.format(
                            "Trying to upload and compile file %s\n", uploadedFile.filename));
                    logger.trace(
                        String.format(
                            "Trying to upload and compile file %s\n", uploadedFile.filename));
                    KCTScript script =
                        turtleCompiler.compileJavaTurtleCode(
                            uploadedFile.filename, uploadedFile.body);
                    logger.trace("Returned KCTScript (it's JSON is): " + script.toJSONString());
                    hook.addScript(script);
                    res.append(
                        String.format(
                            "Successfully uploaded file %s and compiled KnoxCraft Turtle program "
                                + "named %s in programming language %s\n\n",
                            uploadedFile.filename, script.getScriptName(), script.getLanguage()));
                    success++;
                  } catch (TurtleCompilerException e) {
                    logger.warn("Unable to compile Turtle code", e);
                    res.append(String.format("%s\n\n", e.getMessage()));
                    failure++;
                  } catch (TurtleException e) {
                    logger.error("Error in compiling (possibly a server side error)", e);
                    res.append(
                        String.format("Unable to process Turtle code %s\n\n", e.getMessage()));
                    failure++;
                  } catch (Exception e) {
                    logger.error("Unexpected error compiling Turtle code to KCTScript", e);
                    failure++;
                    res.append(String.format("Failed to load script %s\n", entry.getKey()));
                  }
                }
              } else {
                // UNKNOWN CLIENT UPLOAD
                // TODO Unknown client; make a best effort to handle upload
                res.append(
                    String.format(
                        "Unknown upload client: %s; making our best effort to handle the upload"));
              }

              res.append(
                  String.format(
                      "\nSuccessfully uploaded %d KnoxCraft Turtles programs\n", success));
              if (failure > 0) {
                res.append(
                    String.format("\nFailed to upload %d KnoxCraft Turtles programs\n", failure));
              }
              Canary.hooks().callHook(hook);
              writeResponse(ctx.channel(), fullRequest, res.toString(), client);
            } catch (TurtleException e) {
              // XXX can this still happen? Don't we catch all of these?
              writeResponse(ctx.channel(), fullRequest, e.getMessage(), "error");
            }
          }
        }
      }
    } catch (Exception e) {
      logger.error("Internal Server Error: Channel error", e);
      throw e;
    }
  }