/*
    * 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 org.apache.rat.tools;
  
  import java.io.File;
  import java.io.FileNotFoundException;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStreamWriter;
  import java.io.Writer;
  import java.nio.charset.StandardCharsets;
  import java.nio.file.Files;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.List;
  import java.util.Map;
  import java.util.function.Predicate;
  import java.util.function.Supplier;
  
  
  import org.apache.commons.io.IOUtils;
  import org.apache.commons.lang3.StringUtils;
  import org.apache.rat.OptionCollection;
  import org.apache.rat.documentation.options.AntOption;
  import org.apache.rat.utils.DefaultLog;
  
  import static java.lang.String.format;
  
  /**
   * A simple tool to convert CLI options into an Ant report base class.
   */
  public final class AntDocumentation {
      /** The directory to write to. */
      private final File outputDir;
  
      /**
       * Creates apt documentation files for Ant.
       * Requires 1 argument:
       * <ol>
       *     <li>the directory in which to write the documentation files.</li>
       * </ol>
       * @param args the arguments.
       */
      public static void main(final String[] args) {
          if (args.length == 0) {
              System.err.println("Output directory must be specified");
              System.exit(1);
          }
  
          File outputDir = new File(args[0]);
          if (outputDir.exists()) {
              if (!outputDir.isDirectory()) {
                  DefaultLog.getInstance().error(format("%s is not a directory", args[0]));
                  System.exit(1);
              }
          } else {
              if (!outputDir.mkdirs()) {
                  DefaultLog.getInstance().error(format("Can not create directory %s", args[0]));
                  System.exit(1);
              }
          }
          new AntDocumentation(outputDir).execute();
      }
  
     private AntDocumentation(final File outputDir) {
          this.outputDir = outputDir;
      }
  
      public void execute() {
          List<AntOption> options = AntOption.getAntOptions();
  
          writeAttributes(options);
          writeElements(options);
          printValueTypes();
      }
  
      public void writeAttributes(final List<AntOption> options) {
          File f = new File(outputDir, "report_attributes.txt");
          try (Writer out = new OutputStreamWriter(Files.newOutputStream(f.toPath()), StandardCharsets.UTF_8)) {
              printOptions(out, options, AntOption::isAttribute,
                      "The attribute value types are listed in a table at the bottom of this page.");
          } catch (IOException e) {
             throw new RuntimeException(e);
         }
     }
 
     public void writeElements(final List<AntOption> options) {
         File f = new File(outputDir, "report_elements.txt");
         try (Writer out = new OutputStreamWriter(Files.newOutputStream(f.toPath()), StandardCharsets.UTF_8)) {
             printOptions(out, options, AntOption::isElement,
                     "The element value types are listed in a table at the bottom of this page.");
         } catch (IOException e) {
             throw new RuntimeException(e);
         }
     }
     private void printOptions(final Writer out, final List<AntOption> options,
                               final Predicate<AntOption> typeFilter, final String tableCaption) throws IOException {
         boolean hasDeprecated = options.stream().anyMatch(typeFilter.and(AntOption::isDeprecated));
 
         if (hasDeprecated) {
             AptFormat.writeHeader(out, 2, "Current");
         }
 
         List<List<String>> table = new ArrayList<>();
         table.add(Arrays.asList("Name", "Description", "Value Type", "Required"));
         options.stream().filter(typeFilter.and(o -> !o.isDeprecated()))
                 .map(o -> Arrays.asList(o.getName(), o.getDescription(),
                         o.hasArg() ? StringUtils.defaultIfEmpty(o.getArgName(), "String") : "boolean",
                         o.isRequired() ? "true" : "false"))
                 .forEach(table::add);
 
         AptFormat.writeTable(out, table, "*--+--+--+--+", tableCaption);
 
         if (hasDeprecated) {
             AptFormat.writeHeader(out, 2, "Deprecated ");
 
             table.clear();
             table.add(Arrays.asList("Name", "Description", "Argument Type", "Deprecated"));
 
             options.stream().filter(typeFilter.and(AntOption::isDeprecated))
                     .map(o -> Arrays.asList(o.getName(), o.getDescription(),
                             o.hasArg() ? StringUtils.defaultIfEmpty(o.getArgName(), "String") : "boolean",
                             o.getDeprecated()))
                     .forEach(table::add);
 
             AptFormat.writeTable(out, table, "*--+--+--+--+", tableCaption);
         }
     }
 
     private void printValueTypes() {
         File f = new File(outputDir, "report_arg_types.txt");
         try (Writer writer = new OutputStreamWriter(Files.newOutputStream(f.toPath()), StandardCharsets.UTF_8)) {
 
         List<List<String>> table = new ArrayList<>();
         table.add(Arrays.asList("Value Type", "Description"));
 
         for (Map.Entry<String, Supplier<String>> argInfo : OptionCollection.getArgumentTypes().entrySet()) {
             table.add(Arrays.asList(argInfo.getKey(), argInfo.getValue().get()));
         }
 
         AptFormat.writeTable(writer, table, "*--+--+");
 
         } catch (IOException e) {
             throw new RuntimeException(e);
         }
     }
 
     /**
      * A class to write APT formatted text.
      */
     private static final class AptFormat  {
 
         /**
          * Copy the "license.apt" from the resources to the writer.
          * @param writer the writer to write to.
          * @throws IOException on error.
          */
         public static void writeLicense(final Writer writer) throws IOException {
             try (InputStream in = AntDocumentation.class.getResourceAsStream("/license.apt")) {
                 if (in == null) {
                     throw new FileNotFoundException("Could not find license.apt");
                 }
                 IOUtils.copy(in, writer, StandardCharsets.UTF_8);
             }
         }
 
         /**
          * Write a title.
          * @param writer the writer to write to.
          * @param title the title to write.
          * @throws IOException on error.
          */
         public static void writeTitle(final Writer writer, final String title) throws IOException {
             writer.write(format("        -----%n        %1$s%n        -----%n%n%1$s%n%n", title));
         }
 
         /**
          * Write a paragraph.
          * @param writer the writer to write to.
          * @param paragraph the paragraph to write.
          * @throws IOException on error.
          */
         public static void writePara(final Writer writer, final String paragraph) throws IOException {
             writer.write(format("  %s%n%n", paragraph));
         }
 
         /**
          * Write a header.
          * @param writer the writer to write to.
          * @param level the level of the header
          * @param text the text for the header
          * @throws IOException on error.
          */
         public static void writeHeader(final Writer writer, final int level, final String text) throws IOException {
             writer.write(System.lineSeparator());
             for (int i = 0; i < level; i++) {
                 writer.write("*");
             }
             writer.write(format(" %s%n%n", text));
         }
 
         /**
          * Write a list.
          * @param writer the writer to write to.
          * @param list the list to write.
          * @throws IOException on error.
          */
         public static void writeList(final Writer writer, final Collection<String> list) throws IOException {
             for (String s : list) {
                 writer.write(format("    * %s%n", s));
             }
             writer.write(System.lineSeparator());
         }
 
         /**
          * Write a table.
          * @param writer the Writer to write to.
          * @param table the Table to write. A collection of collections of Strings.
          * @param pattern the pattern before and after the table.
          * @param caption the caption for the table.
          * @throws IOException on error.
          */
         public static void writeTable(final Writer writer, final Collection<? extends Collection<String>> table,
                                       final String pattern, final String caption) throws IOException {
             writer.write(format("%s%n", pattern));
             for (Collection<String> row : table) {
                 for (String cell : row) {
                     writer.write(format("| %s ", cell));
                 }
                 writer.write(format("|%n%s%n", pattern));
             }
             if (caption != null) {
                 writer.write(caption);
             }
             writer.write(System.lineSeparator());
         }
 
         /**
          * Write a table entry.
          * @param writer the writer to write to.
          * @param table the table to write
          * @param pattern the pattern before and after the table.
          * @throws IOException on error.
          */
         public static void writeTable(final Writer writer, final Collection<? extends Collection<String>> table,
                                       final String pattern) throws IOException {
             writeTable(writer, table, pattern, null);
         }
     }
 }