/*
    * 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.fileupload2.core;
  
  import static org.junit.jupiter.api.Assertions.assertArrayEquals;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  import static org.junit.jupiter.api.Assertions.fail;
  
  import java.io.ByteArrayOutputStream;
  import java.io.IOException;
  import java.nio.charset.StandardCharsets;
  
  import org.junit.jupiter.api.Test;
  
  /**
   */
  public final class QuotedPrintableDecoderTestCase {
  
      private static void assertEncoded(final String clearText, final String encoded) throws Exception {
          final var expected = clearText.getBytes(StandardCharsets.US_ASCII);
  
          final var out = new ByteArrayOutputStream(encoded.length());
          final var encodedData = encoded.getBytes(StandardCharsets.US_ASCII);
          QuotedPrintableDecoder.decode(encodedData, out);
          final var actual = out.toByteArray();
  
          assertArrayEquals(expected, actual);
      }
  
      private static void assertIOException(final String messageText, final String encoded) {
          final var out = new ByteArrayOutputStream(encoded.length());
          final var encodedData = encoded.getBytes(StandardCharsets.US_ASCII);
          try {
              QuotedPrintableDecoder.decode(encodedData, out);
              fail("Expected IOException");
          } catch (final IOException e) {
              final var em = e.getMessage();
              assertTrue(em.contains(messageText), "Expected to find " + messageText + " in '" + em + "'");
          }
      }
  
      @Test
      public void testBasicEncodeDecode() throws Exception {
          assertEncoded("= Hello there =\r\n", "=3D Hello there =3D=0D=0A");
      }
  
      @Test
      public void testEmptyDecode() throws Exception {
          assertEncoded("", "");
      }
  
      @Test
      public void testInvalidCharDecode() {
          assertThrows(IOException.class, () -> assertEncoded("=\r\n", "=3D=XD=XA"));
      }
  
      @Test
      public void testInvalidQuotedPrintableEncoding() throws Exception {
          assertIOException("truncated escape sequence", "YWJjMTIzXy0uKn4hQCMkJV4mKCkre31cIlxcOzpgLC9bXQ==");
      }
  
      @Test
      public void testInvalidSoftBreak1() throws Exception {
          assertIOException("CR must be followed by LF", "=\r\r");
      }
  
      @Test
      public void testInvalidSoftBreak2() throws Exception {
          assertIOException("CR must be followed by LF", "=\rn");
      }
  
      @Test
      public void testPlainDecode() throws Exception {
          // spaces are allowed in encoded data
          // There are special rules for trailing spaces; these are not currently implemented.
          assertEncoded("The quick brown fox jumps over the lazy dog.", "The quick brown fox jumps over the lazy dog.");
      }
  
      /**
       * This is NOT supported by Commons-Codec, see CODEC-121.
       *
       * @throws Exception
       * @see <a href="https://issues.apache.org/jira/browse/CODEC-121">CODEC-121</a>
       */
     @Test
     public void testSoftLineBreakDecode() throws Exception {
         assertEncoded("If you believe that truth=beauty, then surely mathematics is the most " + "beautiful branch of philosophy.",
                 "If you believe that truth=3Dbeauty, then " + "surely=20=\r\nmathematics is the most beautiful branch of philosophy.");
     }
 
     @Test
     public void testUnsafeDecode() throws Exception {
         assertEncoded("=\r\n", "=3D=0D=0A");
     }
 
     @Test
     public void testUnsafeDecodeLowerCase() throws Exception {
         assertEncoded("=\r\n", "=3d=0d=0a");
     }
 
     @Test
     public void testTruncatedEscape() throws Exception {
         assertIOException("truncated", "=1");
     }
 
 }