/*
    * 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.internal.impl;
  
  import javax.inject.Named;
  import javax.inject.Singleton;
  
  import java.io.IOException;
  import java.io.UncheckedIOException;
  import java.net.URI;
  import java.nio.charset.Charset;
  import java.nio.file.Files;
  import java.nio.file.Path;
  import java.util.Optional;
  
  import org.apache.maven.api.services.Transport;
  import org.eclipse.aether.spi.connector.transport.GetTask;
  import org.eclipse.aether.spi.connector.transport.PutTask;
  import org.eclipse.aether.spi.connector.transport.Transporter;
  
  import static java.util.Objects.requireNonNull;
  
  @Named
  @Singleton
  public class DefaultTransport implements Transport {
      private final URI baseURI;
      private final Transporter transporter;
  
      public DefaultTransport(URI baseURI, Transporter transporter) {
          this.baseURI = requireNonNull(baseURI);
          this.transporter = requireNonNull(transporter);
      }
  
      @Override
      public boolean get(URI relativeSource, Path target) {
          requireNonNull(relativeSource, "relativeSource is null");
          requireNonNull(target, "target is null");
          if (relativeSource.isAbsolute()) {
              throw new IllegalArgumentException("Supplied URI is not relative");
          }
          URI source = baseURI.resolve(relativeSource);
          if (!source.toASCIIString().startsWith(baseURI.toASCIIString())) {
              throw new IllegalArgumentException("Supplied relative URI escapes baseUrl");
          }
          GetTask getTask = new GetTask(source);
          getTask.setDataFile(target.toFile());
          try {
              transporter.get(getTask);
              return true;
          } catch (Exception e) {
              if (Transporter.ERROR_NOT_FOUND != transporter.classify(e)) {
                  throw new RuntimeException(e);
              }
              return false;
          }
      }
  
      @Override
      public Optional<byte[]> getBytes(URI relativeSource) {
          try {
              Path tempPath = null;
              try {
                  tempPath = Files.createTempFile("transport-get", "tmp");
                  if (get(relativeSource, tempPath)) {
                      // TODO: check file size and prevent OOM?
                      return Optional.of(Files.readAllBytes(tempPath));
                  }
                  return Optional.empty();
              } finally {
                  if (tempPath != null) {
                      Files.deleteIfExists(tempPath);
                  }
              }
          } catch (IOException e) {
              throw new UncheckedIOException(e);
          }
      }
  
      @Override
      public Optional<String> getString(URI relativeSource, Charset charset) {
          requireNonNull(charset, "charset is null");
          Optional<byte[]> data = getBytes(relativeSource);
          return data.map(bytes -> new String(bytes, charset));
     }
 
     @Override
     public void put(Path source, URI relativeTarget) {
         requireNonNull(source, "source is null");
         requireNonNull(relativeTarget, "relativeTarget is null");
         if (Files.isRegularFile(source)) {
             throw new IllegalArgumentException("source file does not exist or is not a file");
         }
         if (relativeTarget.isAbsolute()) {
             throw new IllegalArgumentException("Supplied URI is not relative");
         }
         URI target = baseURI.resolve(relativeTarget);
         if (!target.toASCIIString().startsWith(baseURI.toASCIIString())) {
             throw new IllegalArgumentException("Supplied relative URI escapes baseUrl");
         }
 
         PutTask putTask = new PutTask(target);
         putTask.setDataFile(source.toFile());
         try {
             transporter.put(putTask);
         } catch (Exception e) {
             throw new RuntimeException(e);
         }
     }
 
     @Override
     public void putBytes(byte[] source, URI relativeTarget) {
         requireNonNull(source, "source is null");
         try {
             Path tempPath = null;
             try {
                 tempPath = Files.createTempFile("transport-get", "tmp");
                 Files.write(tempPath, source);
                 put(tempPath, relativeTarget);
             } finally {
                 if (tempPath != null) {
                     Files.deleteIfExists(tempPath);
                 }
             }
         } catch (IOException e) {
             throw new UncheckedIOException(e);
         }
     }
 
     @Override
     public void putString(String source, Charset charset, URI relativeTarget) {
         requireNonNull(source, "source string is null");
         requireNonNull(charset, "charset is null");
         putBytes(source.getBytes(charset), relativeTarget);
     }
 
     @Override
     public void close() {
         transporter.close();
     }
 }