/*
    * 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.maven.scm.provider.local.metadata;
  
  import java.io.File;
  import java.io.IOException;
  import java.io.Reader;
  import java.io.Writer;
  import java.util.List;
  
  import org.apache.maven.scm.provider.local.metadata.io.xpp3.LocalScmMetadataXpp3Reader;
  import org.apache.maven.scm.provider.local.metadata.io.xpp3.LocalScmMetadataXpp3Writer;
  import org.codehaus.plexus.util.FileUtils;
  import org.codehaus.plexus.util.ReaderFactory;
  import org.codehaus.plexus.util.WriterFactory;
  import org.codehaus.plexus.util.xml.pull.XmlPullParserException;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Utils for dealing with LocalScmMetadata.
   *
   * @author <a href="mailto:arne@degenring.de">Arne Degenring</a>
   */
  public class LocalScmMetadataUtils {
      /**
       * The name of the metadata file.
       */
      public static final String FILENAME = ".maven-scm-local";
  
      private static final Logger LOGGER = LoggerFactory.getLogger(LocalScmMetadataUtils.class);
  
      /**
       * Builds LocalScmMetadata based on contents of repository.
       *
       * @param repository
       * @return TODO
       * @throws IOException if any
       */
      public LocalScmMetadata buildMetadata(File repository) throws IOException {
          @SuppressWarnings("unchecked")
          List<String> repoFilenames = FileUtils.getFileNames(repository.getAbsoluteFile(), "**", null, false);
          LocalScmMetadata metadata = new LocalScmMetadata();
          metadata.setRepositoryFileNames(repoFilenames);
          return metadata;
      }
  
      /**
       * Writes metadata file.
       *
       * @param destinationDir
       * @param metadata
       * @throws IOException if any
       */
      public void writeMetadata(File destinationDir, LocalScmMetadata metadata) throws IOException {
          File metadataFile = new File(destinationDir, FILENAME);
          metadataFile.createNewFile();
  
          try (Writer writer = WriterFactory.newXmlWriter(metadataFile)) {
              new LocalScmMetadataXpp3Writer().write(writer, metadata);
          }
      }
  
      /**
       * Reads metadata file from given directory.
       *
       * @param dir the directory that should contain the metadata file
       * @return LocalScmMetadata or <code>null</code> in case of problems
       */
      public LocalScmMetadata readMetadata(File dir) {
          File metadataFile = new File(dir, FILENAME);
          if (!metadataFile.exists()) {
              return null;
          }
  
          try (Reader reader = ReaderFactory.newXmlReader(metadataFile)) {
              LocalScmMetadata result = new LocalScmMetadataXpp3Reader().read(reader);
              return result;
          } catch (XmlPullParserException e) {
              if (LOGGER.isWarnEnabled()) {
                  LOGGER.warn("Could not interpret .maven-scm-local - ignoring", e);
              }
              return null;
         } catch (IOException e) {
             if (LOGGER.isWarnEnabled()) {
                 LOGGER.warn("Could not read .maven-scm-local - ignoring", e);
             }
             return null;
         }
     }
 }