/*
    * 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.input;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertFalse;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  
  import java.io.IOException;
  import java.io.InputStream;
  
  import org.junit.jupiter.api.Test;
  
  public class MarkShieldInputStreamTest {
  
      private static final class MarkTestableInputStream extends ProxyInputStream {
          int markcount;
          int readLimit;
  
          public MarkTestableInputStream(final InputStream in) {
              super(in);
          }
  
          @SuppressWarnings("sync-override")
          @Override
          public void mark(final int readLimit) {
              // record that `mark` was called
              this.markcount++;
              this.readLimit = readLimit;
  
              // invoke on super
              super.mark(readLimit);
          }
      }
  
      @Test
      public void testMarkIsNoOpWhenUnderlyingDoesNotSupport() throws IOException {
          try (MarkTestableInputStream in = new MarkTestableInputStream(new NullInputStream(64, false, false));
               final MarkShieldInputStream msis = new MarkShieldInputStream(in)) {
  
              msis.mark(1024);
  
              assertEquals(0, in.markcount);
              assertEquals(0, in.readLimit);
          }
      }
  
      @Test
      public void testMarkIsNoOpWhenUnderlyingSupports() throws IOException {
          try (MarkTestableInputStream in = new MarkTestableInputStream(new NullInputStream(64, true, false));
               final MarkShieldInputStream msis = new MarkShieldInputStream(in)) {
  
              msis.mark(1024);
  
              assertEquals(0, in.markcount);
              assertEquals(0, in.readLimit);
          }
      }
  
      @Test
      public void testMarkSupportedIsFalseWhenUnderlyingFalse() throws IOException {
          // test wrapping an underlying stream which does NOT support marking
          try (InputStream is = new NullInputStream(64, false, false)) {
              assertFalse(is.markSupported());
  
              try (MarkShieldInputStream msis = new MarkShieldInputStream(is)) {
                  assertFalse(msis.markSupported());
              }
          }
      }
  
      @Test
      public void testMarkSupportedIsFalseWhenUnderlyingTrue() throws IOException {
          // test wrapping an underlying stream which supports marking
          try (InputStream is = new NullInputStream(64, true, false)) {
              assertTrue(is.markSupported());
  
              try (MarkShieldInputStream msis = new MarkShieldInputStream(is)) {
                  assertFalse(msis.markSupported());
              }
          }
      }
  
      @Test
     public void testResetThrowsExceptionWhenUnderlyingDoesNotSupport() throws IOException {
         // test wrapping an underlying stream which does NOT support marking
         try (MarkShieldInputStream msis = new MarkShieldInputStream(
                 new NullInputStream(64, false, false))) {
             assertThrows(UnsupportedOperationException.class, msis::reset);
         }
     }
 
     @Test
     public void testResetThrowsExceptionWhenUnderlyingSupports() throws IOException {
         // test wrapping an underlying stream which supports marking
         try (MarkShieldInputStream msis = new MarkShieldInputStream(
                 new NullInputStream(64, true, false))) {
             assertThrows(UnsupportedOperationException.class, msis::reset);
         }
     }
 }