/*
    * 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.commons.io;
  
  import static org.junit.jupiter.api.Assertions.assertArrayEquals;
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertNotNull;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  import java.io.ByteArrayInputStream;
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.io.OutputStream;
  import java.io.OutputStreamWriter;
  import java.io.Reader;
  import java.io.Writer;
  import java.net.URL;
  import java.nio.charset.StandardCharsets;
  import java.nio.file.Files;
  import java.nio.file.Paths;
  
  import org.apache.commons.io.file.TempFile;
  import org.apache.commons.io.input.NullInputStream;
  import org.apache.commons.io.input.NullReader;
  import org.apache.commons.io.output.ByteArrayOutputStream;
  import org.apache.commons.io.output.NullOutputStream;
  import org.apache.commons.io.output.NullWriter;
  import org.apache.commons.io.test.TestUtils;
  import org.apache.commons.io.test.ThrowOnCloseInputStream;
  import org.apache.commons.io.test.ThrowOnFlushAndCloseOutputStream;
  import org.junit.jupiter.api.Test;
  
  /**
   * Tests {@link IOUtils} copy methods.
   */
  public class IOUtilsCopyTest {
  
      /*
       * NOTE this is not particularly beautiful code. A better way to check for
       * flush and close status would be to implement "trojan horse" wrapper
       * implementations of the various stream classes, which set a flag when
       * relevant methods are called. (JT)
       */
  
      private static final int FILE_SIZE = 1024 * 4 + 1;
  
      private final byte[] inData = TestUtils.generateTestData(FILE_SIZE);
  
      @SuppressWarnings("resource") // 'in' is deliberately not closed
      @Test
      public void testCopy_byteArrayOutputStreamToInputStream() throws Exception {
          final java.io.ByteArrayOutputStream out = new java.io.ByteArrayOutputStream();
          out.write(inData);
  
          final InputStream in = IOUtils.copy(out);
  
          final byte[] inData2 = new byte[FILE_SIZE];
          final int inSize = in.read(inData2);
  
          assertEquals(0, in.available(), "Not all bytes were read");
          assertEquals(inData.length, inSize, "Sizes differ");
          assertArrayEquals(inData, inData2, "Content differs");
      }
  
      @Test
      public void testCopy_byteArrayOutputStreamToInputStream_nullOutputStream() {
          assertThrows(NullPointerException.class, () -> IOUtils.copy(null));
      }
  
      @SuppressWarnings("resource") // 'in' is deliberately not closed
      @Test
      public void testCopy_inputStreamToOutputStream() throws Exception {
          InputStream in = new ByteArrayInputStream(inData);
          in = new ThrowOnCloseInputStream(in);
  
          final ByteArrayOutputStream baout = new ByteArrayOutputStream();
          final OutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, false, true);
  
          final int count = IOUtils.copy(in, out);
  
          assertEquals(0, in.available(), "Not all bytes were read");
          assertEquals(inData.length, baout.size(), "Sizes differ");
          assertArrayEquals(inData, baout.toByteArray(), "Content differs");
          assertEquals(inData.length, count);
      }
 
     /**
      * Test Copying file > 2GB - see issue# IO-84
      */
     @Test
     public void testCopy_inputStreamToOutputStream_IO84() throws Exception {
         final long size = (long) Integer.MAX_VALUE + (long) 1;
         final InputStream in = new NullInputStream(size);
         final OutputStream out = NullOutputStream.INSTANCE;
 
         // Test copy() method
         assertEquals(-1, IOUtils.copy(in, out));
 
         // reset the input
         in.close();
 
         // Test copyLarge() method
         assertEquals(size, IOUtils.copyLarge(in, out), "copyLarge()");
     }
 
     @Test
     public void testCopy_inputStreamToOutputStream_nullIn() {
         final OutputStream out = new ByteArrayOutputStream();
         assertThrows(NullPointerException.class, () -> IOUtils.copy((InputStream) null, out));
     }
 
     @Test
     public void testCopy_inputStreamToOutputStream_nullOut() {
         final InputStream in = new ByteArrayInputStream(inData);
         assertThrows(NullPointerException.class, () -> IOUtils.copy(in, (OutputStream) null));
     }
 
     @Test
     public void testCopy_inputStreamToOutputStreamWithBufferSize() throws Exception {
         testCopy_inputStreamToOutputStreamWithBufferSize(1);
         testCopy_inputStreamToOutputStreamWithBufferSize(2);
         testCopy_inputStreamToOutputStreamWithBufferSize(4);
         testCopy_inputStreamToOutputStreamWithBufferSize(8);
         testCopy_inputStreamToOutputStreamWithBufferSize(16);
         testCopy_inputStreamToOutputStreamWithBufferSize(32);
         testCopy_inputStreamToOutputStreamWithBufferSize(64);
         testCopy_inputStreamToOutputStreamWithBufferSize(128);
         testCopy_inputStreamToOutputStreamWithBufferSize(256);
         testCopy_inputStreamToOutputStreamWithBufferSize(512);
         testCopy_inputStreamToOutputStreamWithBufferSize(1024);
         testCopy_inputStreamToOutputStreamWithBufferSize(2048);
         testCopy_inputStreamToOutputStreamWithBufferSize(4096);
         testCopy_inputStreamToOutputStreamWithBufferSize(8192);
         testCopy_inputStreamToOutputStreamWithBufferSize(16384);
     }
 
     @SuppressWarnings("resource") // 'in' is deliberately not closed
     private void testCopy_inputStreamToOutputStreamWithBufferSize(final int bufferSize) throws Exception {
         InputStream in = new ByteArrayInputStream(inData);
         in = new ThrowOnCloseInputStream(in);
 
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final OutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, false, true);
 
         final long count = IOUtils.copy(in, out, bufferSize);
 
         assertEquals(0, in.available(), "Not all bytes were read");
         assertEquals(inData.length, baout.size(), "Sizes differ");
         assertArrayEquals(inData, baout.toByteArray(), "Content differs");
         assertEquals(inData.length, count);
     }
 
     @SuppressWarnings({ "resource", "deprecation" }) // 'in' is deliberately not closed
     @Test
     public void testCopy_inputStreamToWriter() throws Exception {
         InputStream in = new ByteArrayInputStream(inData);
         in = new ThrowOnCloseInputStream(in);
 
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final ThrowOnFlushAndCloseOutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, true, true);
         final Writer writer = new OutputStreamWriter(baout, StandardCharsets.US_ASCII);
 
         IOUtils.copy(in, writer); // deliberately testing deprecated method
         out.off();
         writer.flush();
 
         assertEquals(0, in.available(), "Not all bytes were read");
         assertEquals(inData.length, baout.size(), "Sizes differ");
         assertArrayEquals(inData, baout.toByteArray(), "Content differs");
     }
 
     @SuppressWarnings("resource") // 'in' is deliberately not closed
     @Test
     public void testCopy_inputStreamToWriter_Encoding() throws Exception {
         InputStream in = new ByteArrayInputStream(inData);
         in = new ThrowOnCloseInputStream(in);
 
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final ThrowOnFlushAndCloseOutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, true, true);
         final Writer writer = new OutputStreamWriter(baout, StandardCharsets.US_ASCII);
 
         IOUtils.copy(in, writer, "UTF8");
         out.off();
         writer.flush();
 
         assertEquals(0, in.available(), "Not all bytes were read");
         byte[] bytes = baout.toByteArray();
         bytes = new String(bytes, StandardCharsets.UTF_8).getBytes(StandardCharsets.US_ASCII);
         assertArrayEquals(inData, bytes, "Content differs");
     }
 
     @SuppressWarnings("resource") // 'in' is deliberately not closed
     @Test
     public void testCopy_inputStreamToWriter_Encoding_nullEncoding() throws Exception {
         InputStream in = new ByteArrayInputStream(inData);
         in = new ThrowOnCloseInputStream(in);
 
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final ThrowOnFlushAndCloseOutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, true, true);
         final Writer writer = new OutputStreamWriter(baout, StandardCharsets.US_ASCII);
 
         IOUtils.copy(in, writer, (String) null);
         out.off();
         writer.flush();
 
         assertEquals(0, in.available(), "Not all bytes were read");
         assertEquals(inData.length, baout.size(), "Sizes differ");
         assertArrayEquals(inData, baout.toByteArray(), "Content differs");
     }
 
     @Test
     public void testCopy_inputStreamToWriter_Encoding_nullIn() {
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final OutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, true, true);
         final Writer writer = new OutputStreamWriter(out, StandardCharsets.US_ASCII);
         assertThrows(NullPointerException.class, () -> IOUtils.copy(null, writer, "UTF8"));
     }
 
     @Test
     public void testCopy_inputStreamToWriter_Encoding_nullOut() {
         final InputStream in = new ByteArrayInputStream(inData);
         assertThrows(NullPointerException.class, () -> IOUtils.copy(in, null, "UTF8"));
     }
 
     @SuppressWarnings("deprecation") // deliberately testing deprecated method
     @Test
     public void testCopy_inputStreamToWriter_nullIn() {
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final OutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, true, true);
         final Writer writer = new OutputStreamWriter(out, StandardCharsets.US_ASCII);
         assertThrows(NullPointerException.class, () -> IOUtils.copy((InputStream) null, writer));
     }
 
     @SuppressWarnings("deprecation") // deliberately testing deprecated method
     @Test
     public void testCopy_inputStreamToWriter_nullOut() {
         final InputStream in = new ByteArrayInputStream(inData);
         assertThrows(NullPointerException.class, () -> IOUtils.copy(in, (Writer) null)); // deliberately testing deprecated method
     }
 
     @SuppressWarnings("resource") // 'in' is deliberately not closed
     @Test
     public void testCopy_readerToAppendable() throws Exception {
         InputStream in = new ByteArrayInputStream(inData);
         in = new ThrowOnCloseInputStream(in);
         final Reader reader = new InputStreamReader(in, StandardCharsets.US_ASCII);
 
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final ThrowOnFlushAndCloseOutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, true, true);
         final Writer writer = new OutputStreamWriter(baout, StandardCharsets.US_ASCII);
 
         final long count = IOUtils.copy(reader, (Appendable) writer);
         out.off();
         writer.flush();
         assertEquals(inData.length, count, "The number of characters returned by copy is wrong");
         assertEquals(inData.length, baout.size(), "Sizes differ");
         assertArrayEquals(inData, baout.toByteArray(), "Content differs");
     }
 
     @Test
     public void testCopy_readerToAppendable_IO84() throws Exception {
         final long size = (long) Integer.MAX_VALUE + (long) 1;
         final Reader reader = new NullReader(size);
         final NullWriter writer = new NullWriter();
 
         // Test copy() method
         assertEquals(size, IOUtils.copy(reader, (Appendable) writer));
 
         // reset the input
         reader.close();
 
         // Test copyLarge() method
         assertEquals(size, IOUtils.copyLarge(reader, writer), "copy()");
     }
 
     @Test
     public void testCopy_readerToAppendable_nullIn() {
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final OutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, true, true);
         final Appendable writer = new OutputStreamWriter(out, StandardCharsets.US_ASCII);
         assertThrows(NullPointerException.class, () -> IOUtils.copy(null, writer));
     }
 
     @SuppressWarnings("resource") // 'in' is deliberately not closed
     @Test
     public void testCopy_readerToAppendable_nullOut() {
         InputStream in = new ByteArrayInputStream(inData);
         in = new ThrowOnCloseInputStream(in);
         final Reader reader = new InputStreamReader(in, StandardCharsets.US_ASCII);
         assertThrows(NullPointerException.class, () -> IOUtils.copy(reader, (Appendable) null));
     }
 
     @SuppressWarnings({ "resource", "deprecation" }) // 'in' is deliberately not closed
     @Test
     public void testCopy_readerToOutputStream() throws Exception {
         InputStream in = new ByteArrayInputStream(inData);
         in = new ThrowOnCloseInputStream(in);
         final Reader reader = new InputStreamReader(in, StandardCharsets.US_ASCII);
 
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final OutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, false, true);
 
         IOUtils.copy(reader, out); // deliberately testing deprecated method
         //Note: this method *does* flush. It is equivalent to:
         //  OutputStreamWriter _out = new OutputStreamWriter(fout);
         //  IOUtils.copy( fin, _out, 4096 ); // copy( Reader, Writer, int );
         //  _out.flush();
         //  out = fout;
 
         // Note: rely on the method to flush
         assertEquals(inData.length, baout.size(), "Sizes differ");
         assertArrayEquals(inData, baout.toByteArray(), "Content differs");
     }
 
     @SuppressWarnings("resource") // 'in' is deliberately not closed
     @Test
     public void testCopy_readerToOutputStream_Encoding() throws Exception {
         InputStream in = new ByteArrayInputStream(inData);
         in = new ThrowOnCloseInputStream(in);
         final Reader reader = new InputStreamReader(in, StandardCharsets.US_ASCII);
 
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final OutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, false, true);
 
         IOUtils.copy(reader, out, "UTF16");
         // note: this method *does* flush.
         // note: we don't flush here; this IOUtils method does it for us
 
         byte[] bytes = baout.toByteArray();
         bytes = new String(bytes, StandardCharsets.UTF_16).getBytes(StandardCharsets.US_ASCII);
         assertArrayEquals(inData, bytes, "Content differs");
     }
 
     @SuppressWarnings("resource") // 'in' is deliberately not closed
     @Test
     public void testCopy_readerToOutputStream_Encoding_nullEncoding() throws Exception {
         InputStream in = new ByteArrayInputStream(inData);
         in = new ThrowOnCloseInputStream(in);
         final Reader reader = new InputStreamReader(in, StandardCharsets.US_ASCII);
 
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final OutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, false, true);
 
         IOUtils.copy(reader, out, (String) null);
         // note: this method *does* flush.
         // note: we don't flush here; this IOUtils method does it for us
 
         assertEquals(inData.length, baout.size(), "Sizes differ");
         assertArrayEquals(inData, baout.toByteArray(), "Content differs");
     }
 
     @Test
     public void testCopy_readerToOutputStream_Encoding_nullIn() {
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final OutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, true, true);
         assertThrows(NullPointerException.class, () -> IOUtils.copy(null, out, "UTF16"));
     }
 
     @SuppressWarnings("resource") // 'in' is deliberately not closed
     @Test
     public void testCopy_readerToOutputStream_Encoding_nullOut() {
         InputStream in = new ByteArrayInputStream(inData);
         in = new ThrowOnCloseInputStream(in);
         final Reader reader = new InputStreamReader(in, StandardCharsets.US_ASCII);
         assertThrows(NullPointerException.class, () -> IOUtils.copy(reader, null, "UTF16"));
     }
 
     @SuppressWarnings("deprecation")
     @Test
     public void testCopy_readerToOutputStream_nullIn() { // deliberately testing deprecated method
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final OutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, true, true);
         assertThrows(NullPointerException.class, () -> IOUtils.copy((Reader) null, out));
     }
 
     @SuppressWarnings({ "resource", "deprecation" }) // 'in' is deliberately not closed
     @Test
     public void testCopy_readerToOutputStream_nullOut() {
         InputStream in = new ByteArrayInputStream(inData);
         in = new ThrowOnCloseInputStream(in);
         final Reader reader = new InputStreamReader(in, StandardCharsets.US_ASCII);
         assertThrows(NullPointerException.class, () -> IOUtils.copy(reader, (OutputStream) null)); // deliberately testing deprecated method
     }
 
     @SuppressWarnings("resource") // 'in' is deliberately not closed
     @Test
     public void testCopy_readerToWriter() throws Exception {
         InputStream in = new ByteArrayInputStream(inData);
         in = new ThrowOnCloseInputStream(in);
         final Reader reader = new InputStreamReader(in, StandardCharsets.US_ASCII);
 
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final ThrowOnFlushAndCloseOutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, true, true);
         final Writer writer = new OutputStreamWriter(baout, StandardCharsets.US_ASCII);
 
         final int count = IOUtils.copy(reader, writer);
         out.off();
         writer.flush();
         assertEquals(inData.length, count, "The number of characters returned by copy is wrong");
         assertEquals(inData.length, baout.size(), "Sizes differ");
         assertArrayEquals(inData, baout.toByteArray(), "Content differs");
     }
 
     /**
      * Tests Copying file > 2GB  - see issue# IO-84
      */
     @Test
     public void testCopy_readerToWriter_IO84() throws Exception {
         final long size = (long) Integer.MAX_VALUE + (long) 1;
         final Reader reader = new NullReader(size);
         final Writer writer = new NullWriter();
 
         // Test copy() method
         assertEquals(-1, IOUtils.copy(reader, writer));
 
         // reset the input
         reader.close();
 
         // Test copyLarge() method
         assertEquals(size, IOUtils.copyLarge(reader, writer), "copyLarge()");
     }
 
     @Test
     public void testCopy_readerToWriter_nullIn() {
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         final OutputStream out = new ThrowOnFlushAndCloseOutputStream(baout, true, true);
         final Writer writer = new OutputStreamWriter(out, StandardCharsets.US_ASCII);
         assertThrows(NullPointerException.class, () -> IOUtils.copy((Reader) null, writer));
     }
 
     @SuppressWarnings("resource") // 'in' is deliberately not closed
     @Test
     public void testCopy_readerToWriter_nullOut() {
         InputStream in = new ByteArrayInputStream(inData);
         in = new ThrowOnCloseInputStream(in);
         final Reader reader = new InputStreamReader(in, StandardCharsets.US_ASCII);
         assertThrows(NullPointerException.class, () -> IOUtils.copy(reader, (Writer) null));
     }
 
     @Test
     public void testCopy_URLToFile() throws Exception {
         final String name = "/org/apache/commons/io/abitmorethan16k.txt";
         final URL in = getClass().getResource(name);
         assertNotNull(in, name);
 
         try (TempFile path = TempFile.create("testCopy_URLToFile", ".txt")) {
             IOUtils.copy(in, path.toFile());
             assertArrayEquals(Files.readAllBytes(Paths.get("src/test/resources" + name)), Files.readAllBytes(path.get()));
         }
     }
 
     @Test
     public void testCopy_URLToOutputStream() throws Exception {
         final String name = "/org/apache/commons/io/abitmorethan16k.txt";
         final URL in = getClass().getResource(name);
         assertNotNull(in, name);
 
         final ByteArrayOutputStream baout = new ByteArrayOutputStream();
         IOUtils.copy(in, baout);
 
         assertArrayEquals(Files.readAllBytes(Paths.get("src/test/resources" + name)), baout.toByteArray());
     }
 
 }