/*
    * 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.apache.commons.io.IOUtils.EOF;
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertTimeoutPreemptively;
  
  import java.io.IOException;
  import java.io.StringReader;
  import java.time.Duration;
  import java.util.HashSet;
  
  import org.apache.commons.io.IOUtils;
  import org.apache.commons.io.output.StringBuilderWriter;
  import org.junit.jupiter.api.Test;
  
  public class CharacterFilterReaderTest {
  
      private static final String STRING_FIXTURE = "ababcabcd";
  
      @Test
      public void testInputSize0FilterSize1() throws IOException {
          final StringReader input = new StringReader("");
          final HashSet<Integer> codePoints = new HashSet<>();
          codePoints.add(Integer.valueOf('a'));
          try (CharacterFilterReader reader = new CharacterFilterReader(input, 'A')) {
              assertEquals(-1, reader.read());
          }
      }
  
      @Test
      public void testInputSize1FilterSize1() throws IOException {
          try (StringReader input = new StringReader("a");
              CharacterFilterReader reader = new CharacterFilterReader(input, 'a')) {
              assertEquals(-1, reader.read());
          }
      }
  
      @Test
      public void testInputSize2FilterSize1FilterAll() throws IOException {
          final StringReader input = new StringReader("aa");
          try (CharacterFilterReader reader = new CharacterFilterReader(input, 'a')) {
              assertEquals(-1, reader.read());
          }
      }
  
      @Test
      public void testInputSize2FilterSize1FilterFirst() throws IOException {
          final StringReader input = new StringReader("ab");
          try (CharacterFilterReader reader = new CharacterFilterReader(input, 'a')) {
              assertEquals('b', reader.read());
              assertEquals(-1, reader.read());
          }
      }
  
      @Test
      public void testInputSize2FilterSize1FilterLast() throws IOException {
          final StringReader input = new StringReader("ab");
          try (CharacterFilterReader reader = new CharacterFilterReader(input, 'b')) {
              assertEquals('a', reader.read());
              assertEquals(-1, reader.read());
          }
      }
  
      @Test
      public void testReadFilteringEOF() {
          final StringReader input = new StringReader(STRING_FIXTURE);
          assertTimeoutPreemptively(Duration.ofMillis(500), () -> {
              try (StringBuilderWriter output = new StringBuilderWriter();
                  CharacterFilterReader reader = new CharacterFilterReader(input, EOF)) {
                  int c;
                  while ((c = reader.read()) != EOF) {
                      output.write(c);
                  }
                  assertEquals(STRING_FIXTURE, output.toString());
              }
          });
      }
  
      @Test
      public void testReadIntoBuffer() throws IOException {
          final StringReader input = new StringReader(STRING_FIXTURE);
          try (CharacterFilterReader reader = new CharacterFilterReader(input, 'b')) {
              final char[] buff = new char[9];
             final int charCount = reader.read(buff);
             assertEquals(6, charCount);
             assertEquals("aacacd", new String(buff, 0, charCount));
         }
     }
 
     @Test
     public void testReadUsingReader() throws IOException {
         final StringReader input = new StringReader(STRING_FIXTURE);
         try (StringBuilderWriter output = new StringBuilderWriter();
             CharacterFilterReader reader = new CharacterFilterReader(input, 'b')) {
             IOUtils.copy(reader, output);
             assertEquals("aacacd", output.toString());
         }
     }
 
 }