/*
 * 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 hdfs.jsr203;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertTrue;

import java.io.File;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.Iterator;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileUtil;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.junit.AfterClass;
import org.junit.Assert;
import org.junit.BeforeClass;
import org.junit.Test;

public class TestPath extends TestHadoop {

  private static MiniDFSCluster cluster;
  private static URI clusterUri;

  @BeforeClass
  public static void setUpBeforeClass() throws Exception {
    cluster = startMini(TestPath.class.getName());
    clusterUri = formalizeClusterURI(cluster.getFileSystem().getUri());
  }

  @AfterClass
  public static void teardownClass() throws Exception {
    if (cluster != null) {
      cluster.shutdown();
    }
  }

  private static MiniDFSCluster startMini(String testName) throws IOException {
    File baseDir = new File("./target/hdfs/" + testName).getAbsoluteFile();
    FileUtil.fullyDelete(baseDir);
    Configuration conf = new Configuration();
    conf.set(MiniDFSCluster.HDFS_MINIDFS_BASEDIR, baseDir.getAbsolutePath());
    MiniDFSCluster.Builder builder = new MiniDFSCluster.Builder(conf);
    MiniDFSCluster hdfsCluster = builder.clusterId(testName).build();
    hdfsCluster.waitActive();
    return hdfsCluster;
  }

  @Test
  public void testNormalize() {
    Path rootPath = Paths.get(clusterUri);
    Path start = rootPath.resolve("/tmp/testNormalize/dir1/../file.txt");
    Path expected = rootPath.resolve("/tmp/testNormalize/file.txt");

    assertEquals("Normalized path is incorrect.", expected.toString(),
        start.normalize().toString());
  }

  /**
   * Assertion to check that : <code>p.relativize(p.resolve(q)).equals(q)</code>
   */
  @Test
  public void testRelativizeResolveCombination() {
    Path p = Paths.get(clusterUri).resolve("/a/b");
    Path q = p.getFileSystem().getPath("c", "d");

    assertEquals(q, p.relativize(p.resolve(q)));
  }

  @Test(expected = UnsupportedOperationException.class)
  public void testToFile() {
    Path rootPath = Paths.get(clusterUri);
    Path file = rootPath.resolve("/tmp/testToFile/file.txt");
    file.toFile();
  }

  @Test
  public void testCompareTo() {
    Path rootPath = Paths.get(clusterUri);
    Path path1 = rootPath.resolve("file1.txt");
    Path path2 = rootPath.resolve("file2.txt");

    Assert.assertTrue(path2.compareTo(path1)>0);
    Assert.assertTrue(path2.compareTo(path2)==0);
    Assert.assertTrue(path1.compareTo(path2)<0);
  }

  /**
   * Assertion to check that :
   * <code>Paths.get(p.toUri()).equals(p.toAbsolutePath()) </code>
   * 
   * @throws IOException
   */
  @Test
  public void testToURItoAbsolutePathCombination() throws IOException {
    Path rootPath = Paths.get(clusterUri);

    Files.createDirectories(rootPath.resolve("tmp/testNormalize/dir1/"));
    Files.createFile(rootPath.resolve("tmp/testNormalize/file.txt"));

    Path p = rootPath.resolve("tmp/testNormalize/dir1/../file.txt");
    assertTrue(Paths.get(p.toUri()).equals(p.toAbsolutePath()));

    p = rootPath.resolve("tmp/testNormalize/");
    assertTrue(Paths.get(p.toUri()).equals(p.toAbsolutePath()));
    p = rootPath.resolve("tmp/testNormalize");
    assertTrue(Paths.get(p.toUri()).equals(p.toAbsolutePath()));
    p = rootPath.resolve("tmp/testNormalize/dir1");
    assertTrue(Paths.get(p.toUri()).equals(p.toAbsolutePath()));
    p = rootPath.resolve("tmp/testNormalize/dir1/");
    assertTrue(Paths.get(p.toUri()).equals(p.toAbsolutePath()));
  }

  @Test
  public void testSubpath() throws IOException, URISyntaxException {
    Path rootPath = Paths.get(clusterUri);

    Files.createDirectories(rootPath.resolve("tmp/testNormalize/dir1/"));

    Path p = rootPath.resolve("tmp/testNormalize/dir1/");

    assertEquals("tmp/testNormalize",
        p.subpath(0, p.getNameCount() - 1).toString());
  }

  @Test
  public void testSubpathInvalid() throws IOException, URISyntaxException {
    Path rootPath = Paths.get(clusterUri);

    Files.createDirectories(rootPath.resolve("tmp/testNormalize/dir1/"));

    Path p = rootPath.resolve("tmp/testNormalize/dir1/");

    assertEquals("tmp/testNormalize",
        p.subpath(0, p.getNameCount() - 1).toString());
  }

  @Test(expected = IllegalArgumentException.class)
  public void testSubpathIllegalArgumentException()
      throws IOException, URISyntaxException {
    Path rootPath = Paths.get(clusterUri);

    Files.createDirectories(rootPath.resolve("tmp/testNormalize/dir1/"));

    Path p = rootPath.resolve("tmp/testNormalize/dir1/");
    // These line throw exception
    p.subpath(-5, p.getNameCount() - 1).toString();
  }

  @Test(expected = IllegalArgumentException.class)
  public void testSubpathIllegalArgumentException2()
      throws IOException, URISyntaxException {
    Path rootPath = Paths.get(clusterUri);

    Files.createDirectories(rootPath.resolve("tmp/testNormalize/dir1/"));

    Path p = rootPath.resolve("tmp/testNormalize/dir1/");
    // These line throw exception
    p.subpath(p.getNameCount(), p.getNameCount()).toString();
  }

  @Test(expected = IllegalArgumentException.class)
  public void testSubpathIllegalArgumentException3()
      throws IOException, URISyntaxException {
    Path rootPath = Paths.get(clusterUri);

    Files.createDirectories(rootPath.resolve("tmp/testNormalize/dir1/"));

    Path p = rootPath.resolve("tmp/testNormalize/dir1/");
    // These line throw exception
    p.subpath(0, p.getNameCount() + 1).toString();
  }

  @Test
  public void testGetNameCount() throws IOException {
    Path rootPath = Paths.get(clusterUri);

    Files.createDirectories(rootPath.resolve("tmp/testNormalize/dir1/"));

    Path p = rootPath.resolve("tmp/testNormalize/dir1/");

    assertEquals(0, rootPath.getNameCount());
    assertEquals(3, p.getNameCount());
  }

  @Test
  public void testResolveSibling() throws IOException {
    Path rootPath = Paths.get(clusterUri);

    Files.createDirectories(rootPath.resolve("tmp/testNormalize/dir1/"));

    Path p = rootPath.resolve("tmp/testNormalize/test");
    assertEquals(p, p.resolveSibling(p.getFileName()));
  }

  @Test
  public void getName() throws IOException {
    Path rootPath = Paths.get(clusterUri);

    Path p = rootPath.resolve("tmp/testNormalize/test");
    assertEquals("tmp", p.getName(0).toString());
    assertEquals("testNormalize", p.getName(1).toString());
  }

  @Test(expected = IllegalArgumentException.class)
  public void getNameInvalidIndex() throws IOException {
    Path rootPath = Paths.get(clusterUri);

    Path p = rootPath.resolve("tmp/testNormalize/test");
    p.getName(-1);
  }

  @Test(expected = IllegalArgumentException.class)
  public void getNameInvalidIndex2() throws IOException {
    Path rootPath = Paths.get(clusterUri);

    Path p = rootPath.resolve("tmp/testNormalize/test");
    p.getName(p.getNameCount());
  }

  @Test
  public void startsWith() throws IOException {
    Path rootPath = Paths.get(clusterUri);

    Path p = rootPath.resolve("tmp/testNormalize/test");
    assertTrue(p.startsWith("/tmp"));
  }

  @Test
  public void endsWith() throws IOException {
    Path rootPath = Paths.get(clusterUri);

    Path p = rootPath.resolve("tmp/testNormalize/test");
    assertTrue(p.endsWith("test"));
  }

  @Test
  public void getRoot() throws IOException {
    Path rootPath = Paths.get(clusterUri);

    Path p = rootPath.resolve("tmp/testNormalize/test");
    assertEquals(rootPath, p.getRoot());
  }

  @Test
  public void iterator() throws IOException {
    Path rootPath = Paths.get(clusterUri);

    Path p = rootPath.resolve("tmp/testNormalize/test");
    Iterator<Path> it = p.iterator();
    assertNotNull(it);
    assertEquals("tmp", it.next().toString());
    assertEquals("testNormalize", it.next().toString());
    assertEquals("test", it.next().toString());
  }

  @Test
  public void gethashCode() throws IOException {
    Path rootPath = Paths.get(clusterUri);

    Path p = rootPath.resolve("tmp/testNormalize/test");
    Path p2 = rootPath.resolve("tmp/testNormalize/test");

    assertEquals(p.hashCode(), p2.hashCode());
  }

  @Test
  public void resolveSibling() throws IOException {
    Path rootPath = Paths.get(clusterUri);

    Path p = rootPath.resolve("dir1/dir2/foo");
    Path p2 = rootPath.resolve("dir1/dir2/bar");

    assertEquals(p2, p.resolveSibling("bar"));
  }

  @Test
  public void toURI() throws IOException {
    Path rootPath = Paths.get(clusterUri);

    Path p = rootPath.resolve("dir1/dir2/foo");
    assertTrue(Paths.get(p.toUri()).equals(p .toAbsolutePath()));
  }
}