/*
    * 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.codec.binary;
  
  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.assertThrows;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  
  import java.io.ByteArrayInputStream;
  import java.io.ByteArrayOutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  
  import org.apache.commons.codec.CodecPolicy;
  import org.junit.jupiter.api.Test;
  
  /**
   * Tests {@link Base32InputStream}.
   */
  class Base32InputStreamTest {
  
      private static final String ENCODED_FOO = "MZXW6===";
  
      private static final byte[] CRLF = { (byte) '\r', (byte) '\n' };
  
      private static final byte[] LF = { (byte) '\n' };
  
      private static final String STRING_FIXTURE = "Hello World";
  
      /**
       * Tests skipping past the end of a stream.
       *
       * @throws Throwable
       *             for some failure scenarios.
       */
      @Test
      void testAvailable() throws Throwable {
          final InputStream ins = new ByteArrayInputStream(StringUtils.getBytesIso8859_1(ENCODED_FOO));
          try (Base32InputStream b32stream = new Base32InputStream(ins)) {
              assertEquals(1, b32stream.available());
              assertEquals(3, b32stream.skip(10));
              // End of stream reached
              assertEquals(0, b32stream.available());
              assertEquals(-1, b32stream.read());
              assertEquals(-1, b32stream.read());
              assertEquals(0, b32stream.available());
          }
      }
  
      private void testBase32EmptyInputStream(final int chuckSize) throws Exception {
          final byte[] emptyEncoded = {};
          final byte[] emptyDecoded = {};
          testByteByByte(emptyEncoded, emptyDecoded, chuckSize, CRLF);
          testByChunk(emptyEncoded, emptyDecoded, chuckSize, CRLF);
      }
  
      /**
       * Tests the Base32InputStream implementation against empty input.
       *
       * @throws Exception
       *             for some failure scenarios.
       */
      @Test
      void testBase32EmptyInputStreamMimeChuckSize() throws Exception {
          testBase32EmptyInputStream(BaseNCodec.MIME_CHUNK_SIZE);
      }
  
      // /**
      // * Test for the CODEC-101 bug: InputStream.read(byte[]) should never return 0
      // * because Java's builtin InputStreamReader hates that.
      // *
      // * @throws Exception for some failure scenarios.
      // */
      // @Test
      // void testCodec101() throws Exception {
      // byte[] codec101 = StringUtils.getBytesUtf8(Base32TestData.CODEC_101_MULTIPLE_OF_3);
      // ByteArrayInputStream bais = new ByteArrayInputStream(codec101);
      // Base32InputStream in = new Base32InputStream(bais);
      // byte[] result = new byte[8192];
      // int c = in.read(result);
      // assertTrue("Codec101: First read successful [c=" + c + "]", c > 0);
     //
     // c = in.read(result);
     // assertTrue("Codec101: Second read should report end-of-stream [c=" + c + "]", c < 0);
     // }
 
     /**
      * Another test for the CODEC-101 bug: In commons-codec-1.4 this test shows InputStreamReader explicitly hating an
      * InputStream.read(byte[]) return of 0:
      *
      * java.io.IOException: Underlying input stream returned zero bytes at sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:268) at
      * sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:306) at sun.nio.cs.StreamDecoder.read(StreamDecoder.java:158) at
      * java.io.InputStreamReader.read(InputStreamReader.java:167) at java.io.BufferedReader.fill(BufferedReader.java:136) at
      * java.io.BufferedReader.readLine(BufferedReader.java:299) at java.io.BufferedReader.readLine(BufferedReader.java:362) at
      * org.apache.commons.codec.binary.Base32InputStreamTest.testInputStreamReader(Base32InputStreamTest.java:75)
      *
      * But in commons-codec-1.5 it's fixed. :-)
      *
      * @throws Exception
      *             for some failure scenarios.
      */
     // @Test
     // void testInputStreamReader() throws Exception {
     // byte[] codec101 = StringUtils.getBytesUtf8(Base32TestData.CODEC_101_MULTIPLE_OF_3);
     // ByteArrayInputStream bais = new ByteArrayInputStream(codec101);
     // Base32InputStream in = new Base32InputStream(bais);
     // InputStreamReader isr = new InputStreamReader(in);
     // BufferedReader br = new BufferedReader(isr);
     // String line = br.readLine();
     // assertNotNull("Codec101:  InputStreamReader works!", line);
     // }
 
     /**
      * Test the Base32InputStream implementation against the special NPE inducing input identified in the CODEC-98 bug.
      *
      * @throws Exception
      *             for some failure scenarios.
      */
     // @Test
     // void testCodec98NPE() throws Exception {
     // byte[] codec98 = StringUtils.getBytesUtf8(Base32TestData.CODEC_98_NPE);
     // ByteArrayInputStream data = new ByteArrayInputStream(codec98);
     // Base32InputStream stream = new Base32InputStream(data);
     //
     // // This line causes an NPE in commons-codec-1.4.jar:
     // byte[] decodedBytes = Base32TestData.streamToBytes(stream, new byte[1024]);
     //
     // String decoded = StringUtils.newStringUtf8(decodedBytes);
     // assertEquals(
     // "codec-98 NPE Base32InputStream", Base32TestData.CODEC_98_NPE_DECODED, decoded
     // );
     // }
 
     /**
      * Tests the Base32InputStream implementation against empty input.
      *
      * @throws Exception
      *             for some failure scenarios.
      */
     @Test
     void testBase32EmptyInputStreamPemChuckSize() throws Exception {
         testBase32EmptyInputStream(BaseNCodec.PEM_CHUNK_SIZE);
     }
 
     /**
      * Tests the Base32InputStream implementation.
      *
      * @throws Exception
      *             for some failure scenarios.
      */
     @Test
     void testBase32InputStreamByChunk() throws Exception {
         // Hello World test.
         byte[] encoded = StringUtils.getBytesUtf8(Base32TestData.BASE32_FIXTURE);
         byte[] decoded = StringUtils.getBytesUtf8(Base32TestData.STRING_FIXTURE);
         testByChunk(encoded, decoded, BaseNCodec.MIME_CHUNK_SIZE, CRLF);
 
         // Single Byte test.
         encoded = StringUtils.getBytesUtf8("AA======\r\n");
         decoded = new byte[] { (byte) 0 };
         testByChunk(encoded, decoded, BaseNCodec.MIME_CHUNK_SIZE, CRLF);
 
         // // OpenSSL interop test.
         // encoded = StringUtils.getBytesUtf8(Base32TestData.ENCODED_32_CHARS_PER_LINE);
         // decoded = Base32TestData.DECODED;
         // testByChunk(encoded, decoded, Base32.PEM_CHUNK_SIZE, LF);
         //
         // // Single Line test.
         // String singleLine = Base32TestData.ENCODED_32_CHARS_PER_LINE.replaceAll("\n", "");
         // encoded = StringUtils.getBytesUtf8(singleLine);
         // decoded = Base32TestData.DECODED;
         // testByChunk(encoded, decoded, 0, LF);
 
         // test random data of sizes 0 through 150
         final BaseNCodec codec = new Base32();
         for (int i = 0; i <= 150; i++) {
             final byte[][] randomData = BaseNTestData.randomData(codec, i);
             encoded = randomData[1];
             decoded = randomData[0];
             testByChunk(encoded, decoded, 0, LF);
         }
     }
 
     /**
      * Tests the Base32InputStream implementation.
      *
      * @throws Exception
      *             for some failure scenarios.
      */
     @Test
     void testBase32InputStreamByteByByte() throws Exception {
         // Hello World test.
         byte[] encoded = StringUtils.getBytesUtf8(Base32TestData.BASE32_FIXTURE);
         byte[] decoded = StringUtils.getBytesUtf8(Base32TestData.STRING_FIXTURE);
         testByteByByte(encoded, decoded, BaseNCodec.MIME_CHUNK_SIZE, CRLF);
 
         // Single Byte test.
         encoded = StringUtils.getBytesUtf8("AA======\r\n");
         decoded = new byte[] { (byte) 0 };
         testByteByByte(encoded, decoded, BaseNCodec.MIME_CHUNK_SIZE, CRLF);
 
         // // Single Line test.
         // String singleLine = Base32TestData.ENCODED_32_CHARS_PER_LINE.replaceAll("\n", "");
         // encoded = StringUtils.getBytesUtf8(singleLine);
         // decoded = Base32TestData.DECODED;
         // testByteByByte(encoded, decoded, 0, LF);
 
         // test random data of sizes 0 through 150
         final BaseNCodec codec = new Base32();
         for (int i = 0; i <= 150; i++) {
             final byte[][] randomData = BaseNTestData.randomData(codec, i);
             encoded = randomData[1];
             decoded = randomData[0];
             testByteByByte(encoded, decoded, 0, LF);
         }
     }
 
     @Test
     void testBuilder() {
         assertNotNull(Base32InputStream.builder().getBaseNCodec());
     }
 
     /**
      * Tests method does three tests on the supplied data: 1. encoded ---[DECODE]--> decoded 2. decoded ---[ENCODE]--> encoded 3. decoded
      * ---[WRAP-WRAP-WRAP-etc...] --> decoded
      * <p/>
      * By "[WRAP-WRAP-WRAP-etc...]" we mean situation where the Base32InputStream wraps itself in encode and decode mode over and over
      * again.
      *
      * @param encoded
      *            base32 encoded data
      * @param decoded
      *            the data from above, but decoded
      * @param chunkSize
      *            chunk size (line-length) of the base32 encoded data.
      * @param separator
      *            Line separator in the base32 encoded data.
      * @throws Exception
      *             Usually signifies a bug in the Base32 commons-codec implementation.
      */
     private void testByChunk(final byte[] encoded, final byte[] decoded, final int chunkSize, final byte[] separator) throws Exception {
         // Start with encode.
         try (InputStream in = new Base32InputStream(new ByteArrayInputStream(decoded), true, chunkSize, separator)) {
             final byte[] output = BaseNTestData.streamToBytes(in);
             assertEquals(-1, in.read(), "EOF");
             assertEquals(-1, in.read(), "Still EOF");
             assertArrayEquals(encoded, output, "Streaming base32 encode");
         }
         // Now let's try to decode.
         try (InputStream in = new Base32InputStream(new ByteArrayInputStream(encoded))) {
             final byte[] output = BaseNTestData.streamToBytes(in);
 
             assertEquals(-1, in.read(), "EOF");
             assertEquals(-1, in.read(), "Still EOF");
             assertArrayEquals(decoded, output, "Streaming base32 decode");
         }
         // I always wanted to do this! (wrap encoder with decoder etc.).
         InputStream in = new ByteArrayInputStream(decoded);
         for (int i = 0; i < 10; i++) {
             in = new Base32InputStream(in, true, chunkSize, separator);
             in = new Base32InputStream(in, false);
         }
         final byte[] output = BaseNTestData.streamToBytes(in);
         assertEquals(-1, in.read(), "EOF");
         assertEquals(-1, in.read(), "Still EOF");
         assertArrayEquals(decoded, output, "Streaming base32 wrap-wrap-wrap!");
         in.close();
     }
 
     /**
      * Tests method does three tests on the supplied data: 1. encoded ---[DECODE]--> decoded 2. decoded ---[ENCODE]--> encoded 3. decoded
      * ---[WRAP-WRAP-WRAP-etc...] --> decoded
      * <p/>
      * By "[WRAP-WRAP-WRAP-etc...]" we mean situation where the Base32InputStream wraps itself in encode and decode mode over and over
      * again.
      *
      * @param encoded
      *            base32 encoded data
      * @param decoded
      *            the data from above, but decoded
      * @param chunkSize
      *            chunk size (line-length) of the base32 encoded data.
      * @param separator
      *            Line separator in the base32 encoded data.
      * @throws Exception
      *             Usually signifies a bug in the Base32 commons-codec implementation.
      */
     private void testByteByByte(final byte[] encoded, final byte[] decoded, final int chunkSize, final byte[] separator) throws Exception {
 
         // Start with encode.
         InputStream in;
         in = new Base32InputStream(new ByteArrayInputStream(decoded), true, chunkSize, separator);
         byte[] output = new byte[encoded.length];
         for (int i = 0; i < output.length; i++) {
             output[i] = (byte) in.read();
         }
 
         assertEquals(-1, in.read(), "EOF");
         assertEquals(-1, in.read(), "Still EOF");
         assertArrayEquals(encoded, output, "Streaming base32 encode");
 
         in.close();
 
         // Now let's try to decode.
         in = new Base32InputStream(new ByteArrayInputStream(encoded));
         output = new byte[decoded.length];
         for (int i = 0; i < output.length; i++) {
             output[i] = (byte) in.read();
         }
 
         assertEquals(-1, in.read(), "EOF");
         assertEquals(-1, in.read(), "Still EOF");
         assertArrayEquals(decoded, output, "Streaming base32 decode");
 
         in.close();
 
         // I always wanted to do this! (wrap encoder with decoder etc.).
         in = new ByteArrayInputStream(decoded);
         for (int i = 0; i < 10; i++) {
             in = new Base32InputStream(in, true, chunkSize, separator);
             in = new Base32InputStream(in, false);
         }
         output = new byte[decoded.length];
         for (int i = 0; i < output.length; i++) {
             output[i] = (byte) in.read();
         }
 
         assertEquals(-1, in.read(), "EOF");
         assertEquals(-1, in.read(), "Still EOF");
         assertArrayEquals(decoded, output, "Streaming base32 wrap-wrap-wrap!");
     }
 
     /**
      * Tests the bug reported in CODEC-105. Bad interactions with InputStream when reading one byte at a time.
      */
     @Test
     void testCodec105() throws IOException {
         try (Base32InputStream in = new Base32InputStream(new Codec105ErrorInputStream(), true, 0, null)) {
             for (int i = 0; i < 5; i++) {
                 in.read();
             }
         }
     }
 
     /**
      * Tests the problem reported in CODEC-130. Missing / wrong implementation of skip.
      */
     @Test
     void testCodec130() throws IOException {
         final ByteArrayOutputStream bos = new ByteArrayOutputStream();
         try (Base32OutputStream base32os = new Base32OutputStream(bos)) {
             base32os.write(StringUtils.getBytesUtf8(STRING_FIXTURE));
         }
 
         final ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());
         final Base32InputStream ins = new Base32InputStream(bis);
 
         // we skip the first character read from the reader
         assertEquals(1, ins.skip(1));
         final byte[] decodedBytes = BaseNTestData.streamToBytes(ins, new byte[64]);
         final String str = StringUtils.newStringUtf8(decodedBytes);
 
         assertEquals(STRING_FIXTURE.substring(1), str);
     }
 
     /**
      * Tests markSupported.
      *
      * @throws Exception
      *             for some failure scenarios.
      */
     @Test
     void testMarkSupported() throws Exception {
         final byte[] decoded = StringUtils.getBytesUtf8(Base32TestData.STRING_FIXTURE);
         final ByteArrayInputStream bin = new ByteArrayInputStream(decoded);
         try (Base32InputStream in = new Base32InputStream(bin, true, 4, new byte[] { 0, 0, 0 })) {
             // Always returns false for now.
             assertFalse(in.markSupported(), "Base32InputStream.markSupported() is false");
         }
     }
 
     /**
      * Tests read returning 0
      *
      * @throws Exception
      *             for some failure scenarios.
      */
     @Test
     void testRead0() throws Exception {
         final byte[] decoded = StringUtils.getBytesUtf8(Base32TestData.STRING_FIXTURE);
         final byte[] buf = new byte[1024];
         int bytesRead = 0;
         final ByteArrayInputStream bin = new ByteArrayInputStream(decoded);
         try (Base32InputStream in = new Base32InputStream(bin, true, 4, new byte[] { 0, 0, 0 })) {
             bytesRead = in.read(buf, 0, 0);
             assertEquals(0, bytesRead, "Base32InputStream.read(buf, 0, 0) returns 0");
         }
     }
 
     /**
      * Tests read with null.
      *
      * @throws Exception
      *             for some failure scenarios.
      */
     @Test
     void testReadNull() throws Exception {
         final byte[] decoded = StringUtils.getBytesUtf8(Base32TestData.STRING_FIXTURE);
         final ByteArrayInputStream bin = new ByteArrayInputStream(decoded);
         try (Base32InputStream in = new Base32InputStream(bin, true, 4, new byte[] {0, 0, 0})) {
             assertThrows(NullPointerException.class, () -> in.read(null, 0, 0));
         }
     }
 
     /**
      * Tests read throwing IndexOutOfBoundsException
      *
      * @throws Exception
      *             for some failure scenarios.
      */
     @Test
     void testReadOutOfBounds() throws Exception {
         final byte[] decoded = StringUtils.getBytesUtf8(Base32TestData.STRING_FIXTURE);
         final byte[] buf = new byte[1024];
         final ByteArrayInputStream bin = new ByteArrayInputStream(decoded);
         try (Base32InputStream in = new Base32InputStream(bin, true, 4, new byte[] { 0, 0, 0 })) {
             assertThrows(IndexOutOfBoundsException.class, () -> in.read(buf, -1, 0), "Base32InputStream.read(buf, -1, 0)");
             assertThrows(IndexOutOfBoundsException.class, () -> in.read(buf, 0, -1), "Base32InputStream.read(buf, 0, -1)");
             assertThrows(IndexOutOfBoundsException.class, () -> in.read(buf, buf.length + 1, 0), "Base32InputStream.read(buf, buf.length + 1, 0)");
             assertThrows(IndexOutOfBoundsException.class, () -> in.read(buf, buf.length - 1, 2), "Base32InputStream.read(buf, buf.length - 1, 2)");
         }
     }
 
     /**
      * Tests skipping number of characters larger than the internal buffer.
      *
      * @throws Throwable
      *             for some failure scenarios.
      */
     @Test
     void testSkipBig() throws Throwable {
         final InputStream ins = new ByteArrayInputStream(StringUtils.getBytesIso8859_1(ENCODED_FOO));
         try (Base32InputStream b32stream = new Base32InputStream(ins)) {
             assertEquals(3, b32stream.skip(1024));
             // End of stream reached
             assertEquals(-1, b32stream.read());
             assertEquals(-1, b32stream.read());
         }
     }
 
     /**
      * Tests skipping as a noop
      *
      * @throws Throwable
      *             for some failure scenarios.
      */
     @Test
     void testSkipNone() throws Throwable {
         final InputStream ins = new ByteArrayInputStream(StringUtils.getBytesIso8859_1(ENCODED_FOO));
         try (Base32InputStream b32stream = new Base32InputStream(ins)) {
             final byte[] actualBytes = new byte[6];
             assertEquals(0, b32stream.skip(0));
             b32stream.read(actualBytes, 0, actualBytes.length);
             assertArrayEquals(actualBytes, new byte[] { 102, 111, 111, 0, 0, 0 });
             // End of stream reached
             assertEquals(-1, b32stream.read());
         }
     }
 
     /**
      * Tests skipping past the end of a stream.
      *
      * @throws Throwable
      *             for some failure scenarios.
      */
     @Test
     void testSkipPastEnd() throws Throwable {
         final InputStream ins = new ByteArrayInputStream(StringUtils.getBytesIso8859_1(ENCODED_FOO));
         try (Base32InputStream b32stream = new Base32InputStream(ins)) {
             // due to CODEC-130, skip now skips correctly decoded characters rather than encoded
             assertEquals(3, b32stream.skip(10));
             // End of stream reached
             assertEquals(-1, b32stream.read());
             assertEquals(-1, b32stream.read());
         }
 }
 
     /**
      * Tests skipping to the end of a stream.
      *
      * @throws Throwable
      *             for some failure scenarios.
      */
     @Test
     void testSkipToEnd() throws Throwable {
         final InputStream ins = new ByteArrayInputStream(StringUtils.getBytesIso8859_1(ENCODED_FOO));
         try (Base32InputStream b32stream = new Base32InputStream(ins)) {
             // due to CODEC-130, skip now skips correctly decoded characters rather than encoded
             assertEquals(3, b32stream.skip(3));
             // End of stream reached
             assertEquals(-1, b32stream.read());
             assertEquals(-1, b32stream.read());
         }
     }
 
     /**
      * Tests if negative arguments to skip are handled correctly.
      *
      * @throws Throwable
      *             for some failure scenarios.
      */
     @Test
     void testSkipWrongArgument() throws Throwable {
         final InputStream ins = new ByteArrayInputStream(StringUtils.getBytesIso8859_1(ENCODED_FOO));
         try (Base32InputStream b32stream = new Base32InputStream(ins)) {
             assertThrows(IllegalArgumentException.class, () -> b32stream.skip(-10));
         }
     }
 
     /**
      * Test strict decoding.
      *
      * @throws Exception
      *             for some failure scenarios.
      */
     @Test
     void testStrictDecoding() throws Exception {
         for (final String s : Base32Test.BASE32_IMPOSSIBLE_CASES) {
             final byte[] encoded = StringUtils.getBytesUtf8(s);
             final Base32InputStream in = new Base32InputStream(new ByteArrayInputStream(encoded), false);
             // Default is lenient decoding; it should not throw
             assertFalse(in.isStrictDecoding());
             BaseNTestData.streamToBytes(in);
             // Strict decoding should throw
             final Base32InputStream in2 = new Base32InputStream(new ByteArrayInputStream(encoded), false, 0, null, CodecPolicy.STRICT);
             assertTrue(in2.isStrictDecoding());
             assertThrows(IllegalArgumentException.class, () -> BaseNTestData.streamToBytes(in2));
             // Same with a builder
             try (Base32InputStream in3 = Base32InputStream.builder()
                     .setInputStream(new ByteArrayInputStream(encoded))
                     .setEncode(false)
                     .setBaseNCodec(Base32.builder().setLineLength(0).setLineSeparator(null).setDecodingPolicy(CodecPolicy.STRICT).get())
                     .get()) {
                 assertTrue(in3.isStrictDecoding());
                 assertThrows(IllegalArgumentException.class, () -> BaseNTestData.streamToBytes(in3));
             }
         }
     }
 }