content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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.github.jobson.scripting.functions;
  
  import com.github.jobson.jobinputs.file.FileInput;
  import com.github.jobson.jobinputs.filearray.FileArrayInput;
  import com.github.jobson.scripting.FreeFunction;
  
  import java.io.IOException;
  import java.nio.file.Files;
  import java.nio.file.Path;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Map;
  import java.util.stream.Collectors;
  
  import static java.lang.String.format;
  
  public final class ToDirFunction implements FreeFunction {
  
      private final Path workingDir;
  
      public ToDirFunction(Path workingDir) {
          this.workingDir = workingDir;
      }
  
      @Override
      public Object call(Object... args) {
          if (args.length != 1) {
              throw new RuntimeException(format("toDir called with %s args (expects 1)", args.length));
          }
  
          final Object arg = args[0];
  
          if (!(arg instanceof FileArrayInput)) {
              throw new RuntimeException(format(
                      "toDir called with a %s object, should be called with a file[] list (e.g. ${inputs.someFileList})",
                      arg.getClass().getSimpleName()));
          }
  
          final FileArrayInput fai = (FileArrayInput)arg;
  
          // create a randomly-named dir in the working directory
          try {
              final Path dir = Files.createTempDirectory(workingDir, "toDir");
  
              // for each file the user supplies, there might be duplicate names. This is
              // allowed by the API because it's conceivable that a user would drag/add multiple
              // identically-named files from their computer an expect things to "just work" without
              // having to fuck around and rename their files to satisfy the software.
              //
              // This creates a problem server-side, though, because Jobson needs to write all
              // the files into a single directory to satisfy this function because downstream
              // applications may (reasonably) expect that the directory created by `toDir`
              // dumps all files in one directory with **no nesting**.
              //
              // Because of this, `toDir` has to rename duplicate files (unlike `toFile`). If
              // people whine about that then we can add a `toDirNested` or something.
  
              // Implementation:
              //
              // - stable-partition (groupingBy, in this case) the file list so that duplicate
              //   entries become adjacent
              //
              //  - stable partition used because the user may have "encoded" some information
              //    in their addition order (e.g. "I added the files in order of importance")
              //
              //  - the user may also have paired files from different directories so, again,
              //    ordering might be important
              //
              //  - e.g. A A.related A A.related ----> 1_A 2_A 1_A.related 2_A.related
              //
              // - If the partition contains 1 entry, there's no duplicates, so don't prefix;
              //   otherwise, do prefix
  
              final Map<String, List<FileInput>> sortedFiles =
                      fai.getFiles().stream().collect(Collectors.groupingBy(FileInput::getFilename));
  
              for (Map.Entry<String, List<FileInput>> e : sortedFiles.entrySet()) {
                  final String filename = e.getKey();
                  final List<FileInput> files = e.getValue();
  
                  if (files.size() == 1) {
                      final Path filePath = dir.resolve(filename);
                      Files.write(filePath, files.get(0).getData());
                  } else {
                      for (int i = 0; i < files.size(); i++) {
                          final String prefixedName = format("%s_%s", (i + 1), filename);
                          final Path filePath = dir.resolve(prefixedName);
                          Files.write(filePath, files.get(i).getData());
                      }
                  }
              }
              return dir.toString();
          } catch (IOException ex) {
              throw new RuntimeException(ex);
          }
      }
  }
  