/*
    * 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.shared.dependency.analyzer;
  
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.net.URL;
  import java.nio.charset.StandardCharsets;
  import java.nio.file.Files;
  import java.nio.file.Path;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.jar.JarOutputStream;
  import java.util.zip.ZipEntry;
  
  import org.junit.jupiter.api.Test;
  import org.junit.jupiter.api.io.TempDir;
  
  import static org.assertj.core.api.Assertions.assertThat;
  import static org.assertj.core.api.Assertions.fail;
  
  /**
   * Tests <code>ClassFileVisitorUtils</code>.
   *
   * @author <a href="mailto:markhobson@gmail.com">Mark Hobson</a>
   * @see ClassFileVisitorUtils
   */
  class ClassFileVisitorUtilsTest {
  
      @TempDir
      private Path tempDir;
  
      private TestVisitor visitor = new TestVisitor();
  
      private static class TestVisitor implements ClassFileVisitor {
          final List<String> classNames = new ArrayList<>();
  
          final List<String> data = new ArrayList<>();
  
          @Override
          public void visitClass(String className, InputStream in) {
              classNames.add(className);
              BufferedReader reader = new BufferedReader(new InputStreamReader(in, StandardCharsets.UTF_8));
              reader.lines().forEach(data::add);
          }
      }
  
      @Test
      void testAcceptJar() throws IOException {
          Path path = Files.createTempFile(tempDir, "test", ".jar");
  
          try (JarOutputStream out = new JarOutputStream(Files.newOutputStream(path))) {
              addZipEntry(out, "a/b/c.class", "class a.b.c");
              addZipEntry(out, "x/y/z.class", "class x.y.z");
          }
  
          ClassFileVisitorUtils.accept(path.toUri().toURL(), visitor);
  
          assertThat(visitor.classNames).contains("a.b.c");
          assertThat(visitor.classNames).contains("x.y.z");
          assertThat(visitor.data).contains("class a.b.c");
          assertThat(visitor.data).contains("class x.y.z");
      }
  
      @Test
      void testAcceptJarWithNonClassEntry() throws IOException {
          Path path = Files.createTempFile(tempDir, "test", ".jar");
  
          try (JarOutputStream out = new JarOutputStream(Files.newOutputStream(path))) {
              addZipEntry(out, "a/b/c.jpg", "jpeg a.b.c");
          }
  
          ClassFileVisitorUtils.accept(path.toUri().toURL(), visitor);
  
          assertThat(visitor.classNames).isEmpty();
      }
  
      @Test
      void testAcceptDir() throws IOException {
          Path dir = Files.createTempDirectory(tempDir, "d-a-test");
  
         Path abDir = Files.createDirectories(dir.resolve("a/b"));
         writeToFile(abDir, "c.class", "class a.b.c");
 
         Path xyDir = Files.createDirectories(dir.resolve("x/y"));
         writeToFile(xyDir, "z.class", "class x.y.z");
 
         ClassFileVisitorUtils.accept(dir.toUri().toURL(), visitor);
 
         assertThat(visitor.classNames).contains("a.b.c");
         assertThat(visitor.classNames).contains("x.y.z");
         assertThat(visitor.data).contains("class a.b.c");
         assertThat(visitor.data).contains("class x.y.z");
     }
 
     @Test
     void testAcceptDirWithNonClassFile() throws IOException {
         Path dir = Files.createTempDirectory(tempDir, "d-a-test");
 
         Path abDir = Files.createDirectories(dir.resolve("a/b"));
         writeToFile(abDir, "c.jpg", "jpeg a.b.c");
 
         ClassFileVisitorUtils.accept(dir.toUri().toURL(), visitor);
 
         assertThat(visitor.classNames).isEmpty();
     }
 
     @Test
     void testAcceptWithFile() throws IOException {
         Path path = Files.createTempFile(tempDir, "test", ".class");
         URL url = path.toUri().toURL();
 
         try {
             ClassFileVisitorUtils.accept(url, visitor);
             fail("expected IllegalArgumentException");
         } catch (IllegalArgumentException exception) {
             assertThat(exception).hasMessage("Cannot accept visitor on URL: " + url);
         }
     }
 
     @Test
     void testAcceptWithUnsupportedScheme() throws IOException {
         URL url = new URL("http://localhost/");
 
         try {
             ClassFileVisitorUtils.accept(url, visitor);
             fail("expected IllegalArgumentException");
         } catch (IllegalArgumentException exception) {
             assertThat(exception).hasMessage("Cannot accept visitor on URL: " + url);
         }
     }
 
     private void writeToFile(Path parent, String file, String data) throws IOException {
         Files.write(parent.resolve(file), data.getBytes(StandardCharsets.UTF_8));
     }
 
     private void addZipEntry(JarOutputStream out, String fileName, String content) throws IOException {
         out.putNextEntry(new ZipEntry(fileName));
         byte[] bytes = content.getBytes(StandardCharsets.UTF_8);
         out.write(bytes, 0, bytes.length);
     }
 }