/*
    * 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
    *
    *      https://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.commons.io.build;
  
  import static org.junit.jupiter.api.Assertions.assertArrayEquals;
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertFalse;
  import static org.junit.jupiter.api.Assertions.assertNotNull;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  
  import java.io.Closeable;
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.io.RandomAccessFile;
  import java.io.Reader;
  import java.io.Writer;
  import java.nio.ByteBuffer;
  import java.nio.channels.ReadableByteChannel;
  import java.nio.channels.SeekableByteChannel;
  import java.nio.channels.WritableByteChannel;
  import java.nio.charset.Charset;
  import java.nio.charset.StandardCharsets;
  import java.nio.file.Files;
  import java.nio.file.OpenOption;
  import java.nio.file.Path;
  import java.nio.file.StandardOpenOption;
  import java.util.Objects;
  
  import org.apache.commons.io.FileUtils;
  import org.apache.commons.io.IOUtils;
  import org.apache.commons.io.build.AbstractOrigin.RandomAccessFileOrigin;
  import org.junit.jupiter.api.AfterEach;
  import org.junit.jupiter.api.BeforeEach;
  import org.junit.jupiter.api.Test;
  import org.junit.jupiter.api.io.TempDir;
  import org.junit.jupiter.params.ParameterizedTest;
  import org.junit.jupiter.params.provider.EnumSource;
  
  /**
   * Tests {@link AbstractOrigin} and subclasses.
   *
   * @param <T> the type of instances to build.
   * @param <B> the type of builder subclass.
   */
  public abstract class AbstractOriginTest<T, B extends AbstractOrigin<T, B>> {
  
      protected static final String FILE_RES_RO = "/org/apache/commons/io/test-file-20byteslength.bin";
      protected static final String FILE_NAME_RO = "src/test/resources" + FILE_RES_RO;
      protected static final String FILE_NAME_RW = AbstractOriginTest.class.getSimpleName() + ".txt";
      private static final int RO_LENGTH = 20;
  
      protected AbstractOrigin<T, B> originRo;
      protected AbstractOrigin<T, B> originRw;
  
      @TempDir
      protected Path tempPath;
  
      @BeforeEach
      void beforeEach() throws IOException {
          setOriginRo(newOriginRo());
          resetOriginRw();
          setOriginRw(newOriginRw());
      }
  
      private void checkRead(final ReadableByteChannel channel) throws IOException {
          final ByteBuffer buffer = ByteBuffer.allocate(RO_LENGTH);
          int read = channel.read(buffer);
          assertEquals(RO_LENGTH, read);
          assertArrayEquals(getFixtureByteArray(), buffer.array());
          // Channel is at EOF
          buffer.clear();
          read = channel.read(buffer);
          assertEquals(-1, read);
      }
  
      private void checkWrite(final WritableByteChannel channel) throws IOException {
          final ByteBuffer buffer = ByteBuffer.wrap(getFixtureByteArray());
          final int written = channel.write(buffer);
          assertEquals(RO_LENGTH, written);
      }
  
      @AfterEach
     void cleanup() {
         final T originRo = getOriginRo().get();
         if (originRo instanceof Closeable) {
             IOUtils.closeQuietly((Closeable) originRo);
         }
         final T originRw = getOriginRw().get();
         if (originRw instanceof Closeable) {
             IOUtils.closeQuietly((Closeable) originRw);
         }
     }
 
     byte[] getFixtureByteArray() throws IOException {
         return IOUtils.resourceToByteArray(FILE_RES_RO);
     }
 
     String getFixtureString() throws IOException {
         return IOUtils.resourceToString(FILE_RES_RO, StandardCharsets.UTF_8);
     }
 
     protected AbstractOrigin<T, B> getOriginRo() {
         return Objects.requireNonNull(originRo, "originRo");
     }
 
     protected AbstractOrigin<T, B> getOriginRw() {
         return Objects.requireNonNull(originRw, "originRw");
     }
 
     @SuppressWarnings("resource")
     private boolean isValid(final RandomAccessFile raf) throws IOException {
         return Objects.requireNonNull(raf).getFD().valid();
     }
 
     protected abstract B newOriginRo() throws IOException;
 
     protected abstract B newOriginRw() throws IOException;
 
     protected void resetOriginRw() throws IOException {
         // No-op
     }
 
     protected void setOriginRo(final AbstractOrigin<T, B> origin) {
         this.originRo = origin;
     }
 
     protected void setOriginRw(final AbstractOrigin<T, B> origin) {
         this.originRw = origin;
     }
 
     @Test
     void testGetByteArray() throws IOException {
         assertArrayEquals(getFixtureByteArray(), getOriginRo().getByteArray());
     }
 
     @Test
     void testGetByteArrayAt_0_0() throws IOException {
         assertArrayEquals(new byte[] {}, getOriginRo().getByteArray(0, 0));
     }
 
     @Test
     void testGetByteArrayAt_0_1() throws IOException {
         assertArrayEquals(new byte[] { '1' }, getOriginRo().getByteArray(0, 1));
     }
 
     @Test
     void testGetByteArrayAt_1_1() throws IOException {
         assertArrayEquals(new byte[] { '2' }, getOriginRo().getByteArray(1, 1));
     }
 
     @Test
     void testGetCharSequence() throws IOException {
         final CharSequence charSequence = getOriginRo().getCharSequence(StandardCharsets.UTF_8);
         assertNotNull(charSequence);
         assertEquals(getFixtureString(), charSequence.toString());
     }
 
     @Test
     void testGetFile() throws IOException {
         testGetFile(getOriginRo().getFile(), RO_LENGTH);
         FileUtils.touch(getOriginRw().getFile());
         testGetFile(getOriginRw().getFile(), 0);
     }
 
     private void testGetFile(final File file, final long expectedLen) throws IOException {
         assertNotNull(file);
         assertTrue(file.exists(), () -> "File does not exist: " + file);
         final int length = FileUtils.readFileToByteArray(file).length;
         assertEquals(length, expectedLen, () -> String.format("File %s, actual length=%,d", file, length));
     }
 
     @Test
     void testGetInputStream() throws IOException {
         try (InputStream inputStream = getOriginRo().getInputStream()) {
             assertNotNull(inputStream);
             assertArrayEquals(getFixtureByteArray(), IOUtils.toByteArray(inputStream));
         }
     }
 
     @Test
     void testGetOutputStream() throws IOException {
         try (OutputStream output = getOriginRw().getOutputStream()) {
             assertNotNull(output);
         }
     }
 
     @Test
     void testGetPath() throws IOException {
         testGetPath(getOriginRo().getPath(), RO_LENGTH);
         FileUtils.touch(getOriginRw().getPath().toFile());
         testGetPath(getOriginRw().getPath(), 0);
     }
 
     private void testGetPath(final Path path, final long expectedLen) throws IOException {
         assertNotNull(path);
         assertTrue(Files.exists(path));
         final int length = Files.readAllBytes(path).length;
         assertEquals(length, expectedLen, () -> String.format("Path %s, actual length=%,d", path, length));
     }
 
     @Test
     void testGetRandomAccessFile() throws IOException {
         // Default
         try (RandomAccessFile raf = getOriginRo().getRandomAccessFile()) {
             assertNotNull(raf);
             assertTrue(isValid(raf));
         }
         final boolean isRafOriginRo = getOriginRo() instanceof RandomAccessFileOrigin;
         final boolean isRafOriginRw = getOriginRw() instanceof RandomAccessFileOrigin;
         // Same as above, but underlying resource is now closed.
         try (RandomAccessFile raf = getOriginRo().getRandomAccessFile()) {
             assertNotNull(raf);
             assertFalse(isRafOriginRo && isValid(raf));
         }
         // Read
         try (RandomAccessFile raf = getOriginRo().getRandomAccessFile(StandardOpenOption.READ)) {
             assertNotNull(raf);
             assertFalse(isRafOriginRo && isValid(raf));
         }
         // Write, first access
         try (RandomAccessFile raf = getOriginRw().getRandomAccessFile(StandardOpenOption.WRITE)) {
             assertNotNull(raf);
             if (isRafOriginRw || getOriginRw().getFile() != null) {
                 assertTrue(isValid(raf), () -> getOriginRw().toString());
             } else {
                 // Can't get there from here.
                 assertFalse(isValid(raf), () -> getOriginRw().toString());
             }
         }
         // Read, Write, underlying resource is now closed.
         try (RandomAccessFile raf = getOriginRw().getRandomAccessFile(StandardOpenOption.READ, StandardOpenOption.WRITE)) {
             assertNotNull(raf);
             assertFalse(isRafOriginRw && isValid(raf));
         }
     }
 
     @ParameterizedTest
     @EnumSource(StandardOpenOption.class)
     void testGetRandomAccessFile(final OpenOption openOption) throws IOException {
         // Default
         try (RandomAccessFile raf = getOriginRw().getRandomAccessFile()) {
             assertNotNull(raf);
             assertTrue(isValid(raf));
         }
         // Same as above, but underlying resource is now closed.
         final boolean isRafOrigin = getOriginRw() instanceof RandomAccessFileOrigin;
         try (RandomAccessFile raf = getOriginRw().getRandomAccessFile()) {
             assertNotNull(raf);
             assertFalse(isRafOrigin && isValid(raf));
         }
         try (RandomAccessFile raf = getOriginRw().getRandomAccessFile(openOption)) {
             assertNotNull(raf);
             assertFalse(isRafOrigin && isValid(raf));
         }
         try (RandomAccessFile raf = getOriginRw().getRandomAccessFile(openOption)) {
             assertNotNull(raf);
             assertFalse(isRafOrigin && isValid(raf));
         }
     }
 
     @Test
     void testGetReadableByteChannel() throws IOException {
         try (ReadableByteChannel channel = getOriginRo().getChannel(ReadableByteChannel.class, StandardOpenOption.READ)) {
             final SeekableByteChannel seekable = channel instanceof SeekableByteChannel ? (SeekableByteChannel) channel : null;
             assertNotNull(channel);
             assertTrue(channel.isOpen());
             if (seekable != null) {
                 assertEquals(0, seekable.position());
                 assertEquals(RO_LENGTH, seekable.size());
             }
             checkRead(channel);
             if (seekable != null) {
                 assertEquals(RO_LENGTH, seekable.position());
             }
         }
     }
 
     @Test
     void testGetReader() throws IOException {
         try (Reader reader = getOriginRo().getReader(Charset.defaultCharset())) {
             assertNotNull(reader);
         }
         setOriginRo(newOriginRo());
         try (Reader reader = getOriginRo().getReader(null)) {
             assertNotNull(reader);
         }
         setOriginRo(newOriginRo());
         try (Reader reader = getOriginRo().getReader(StandardCharsets.UTF_8)) {
             assertNotNull(reader);
             assertEquals(getFixtureString(), IOUtils.toString(reader));
         }
     }
 
     @Test
     void testGetWritableByteChannel() throws IOException {
         final boolean supportsRead;
         try (WritableByteChannel channel = getOriginRw().getChannel(WritableByteChannel.class, StandardOpenOption.WRITE)) {
             supportsRead = channel instanceof ReadableByteChannel;
             final SeekableByteChannel seekable = channel instanceof SeekableByteChannel ? (SeekableByteChannel) channel : null;
             assertNotNull(channel);
             assertTrue(channel.isOpen());
             if (seekable != null) {
                 assertEquals(0, seekable.position());
                 assertEquals(0, seekable.size());
             }
             checkWrite(channel);
             if (seekable != null) {
                 assertEquals(RO_LENGTH, seekable.position());
                 assertEquals(RO_LENGTH, seekable.size());
             }
         }
         if (supportsRead) {
             setOriginRw(newOriginRw());
             try (ReadableByteChannel channel = getOriginRw().getChannel(ReadableByteChannel.class, StandardOpenOption.READ)) {
                 assertNotNull(channel);
                 assertTrue(channel.isOpen());
                 checkRead(channel);
             }
         }
         setOriginRw(newOriginRw());
         try (WritableByteChannel channel = getOriginRw().getChannel(WritableByteChannel.class, StandardOpenOption.WRITE)) {
             final SeekableByteChannel seekable = channel instanceof SeekableByteChannel ? (SeekableByteChannel) channel : null;
             assertNotNull(channel);
             assertTrue(channel.isOpen());
             if (seekable != null) {
                 seekable.position(RO_LENGTH);
                 assertEquals(RO_LENGTH, seekable.position());
                 assertEquals(RO_LENGTH, seekable.size());
                 // Truncate
                 final int newSize = RO_LENGTH / 2;
                 seekable.truncate(newSize);
                 assertEquals(newSize, seekable.position());
                 assertEquals(newSize, seekable.size());
                 // Rewind
                 seekable.position(0);
                 assertEquals(0, seekable.position());
             }
         }
     }
 
     @Test
     void testGetWriter() throws IOException {
         try (Writer writer = getOriginRw().getWriter(Charset.defaultCharset())) {
             assertNotNull(writer);
         }
         setOriginRw(newOriginRw());
         try (Writer writer = getOriginRw().getWriter(null)) {
             assertNotNull(writer);
         }
     }
 
     @Test
     void testSize() throws IOException {
         assertEquals(RO_LENGTH, getOriginRo().getByteArray().length);
     }
 }