/*
    * 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.io.input;
  
  import static org.apache.commons.io.input.ReversedLinesFileReaderParamBlockSizeTest.assertEqualsAndNoLineBreaks;
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  
  import java.io.File;
  import java.io.IOException;
  import java.io.UnsupportedEncodingException;
  import java.net.URISyntaxException;
  import java.nio.charset.StandardCharsets;
  import java.util.List;
  
  import org.apache.commons.io.IOUtils;
  import org.apache.commons.io.TestResources;
  import org.junit.jupiter.api.Test;
  import org.junit.jupiter.params.ParameterizedTest;
  import org.junit.jupiter.params.provider.MethodSource;
  
  class ReversedLinesFileReaderSimpleTest {
  
      /*
       * Tests IO-639.
       */
      @ParameterizedTest
      @MethodSource("org.apache.commons.io.input.ReversedLinesFileReaderParamBlockSizeTest#blockSizes")
      void testEmptyFirstLine(final int blockSize) throws Exception {
          final File testFileEmptyFirstLine = TestResources.getFile("/empty-first-line.bin");
          try (ReversedLinesFileReader reversedLinesFileReader = new ReversedLinesFileReader(testFileEmptyFirstLine,
                  blockSize, StandardCharsets.US_ASCII.name())) {
              assertEqualsAndNoLineBreaks("test2", reversedLinesFileReader.readLine());
              assertEqualsAndNoLineBreaks("", reversedLinesFileReader.readLine());
              assertEqualsAndNoLineBreaks("test1", reversedLinesFileReader.readLine());
              assertEqualsAndNoLineBreaks("", reversedLinesFileReader.readLine());
          }
      }
  
      @ParameterizedTest
      @MethodSource("org.apache.commons.io.input.ReversedLinesFileReaderParamBlockSizeTest#blockSizes")
      void testFileSizeIsExactMultipleOfBlockSize(final int blockSize) throws URISyntaxException, IOException {
          final File testFile20Bytes = TestResources.getFile("/test-file-20byteslength.bin");
          try (ReversedLinesFileReader reversedLinesFileReader = new ReversedLinesFileReader(testFile20Bytes, blockSize,
                  StandardCharsets.ISO_8859_1.name())) {
              assertEqualsAndNoLineBreaks("987654321", reversedLinesFileReader.readLine());
              assertEqualsAndNoLineBreaks("123456789", reversedLinesFileReader.readLine());
          }
      }
  
      @ParameterizedTest
      @MethodSource("org.apache.commons.io.input.ReversedLinesFileReaderParamBlockSizeTest#blockSizes")
      void testLineCount(final int blockSize) throws URISyntaxException, IOException {
          final File testFile20Bytes = TestResources.getFile("/test-file-20byteslength.bin");
          try (ReversedLinesFileReader reversedLinesFileReader = new ReversedLinesFileReader(testFile20Bytes, blockSize,
                  StandardCharsets.ISO_8859_1.name())) {
              assertThrows(IllegalArgumentException.class, () -> reversedLinesFileReader.readLines(-1));
              assertTrue(reversedLinesFileReader.readLines(0).isEmpty());
              final List<String> lines = reversedLinesFileReader.readLines(2);
              assertEqualsAndNoLineBreaks("987654321", lines.get(0));
              assertEqualsAndNoLineBreaks("123456789", lines.get(1));
              assertTrue(reversedLinesFileReader.readLines(0).isEmpty());
              assertTrue(reversedLinesFileReader.readLines(10000).isEmpty());
          }
      }
  
      @ParameterizedTest
      @MethodSource("org.apache.commons.io.input.ReversedLinesFileReaderParamBlockSizeTest#blockSizes")
      void testToString(final int blockSize) throws URISyntaxException, IOException {
          final File testFile20Bytes = TestResources.getFile("/test-file-20byteslength.bin");
          try (ReversedLinesFileReader reversedLinesFileReader = new ReversedLinesFileReader(testFile20Bytes, blockSize,
                  StandardCharsets.ISO_8859_1.name())) {
              assertThrows(IllegalArgumentException.class, () -> reversedLinesFileReader.toString(-1));
              assertTrue(reversedLinesFileReader.readLines(0).isEmpty());
              final String lines = reversedLinesFileReader.toString(2);
              assertEquals("123456789" + System.lineSeparator() + "987654321" + System.lineSeparator(), lines);
              assertTrue(reversedLinesFileReader.toString(0).isEmpty());
              assertTrue(reversedLinesFileReader.toString(10000).isEmpty());
          }
      }
  
      @Test
      void testUnsupportedEncodingBig5() throws URISyntaxException {
          final File testFileEncodingBig5 = TestResources.getFile("/test-file-empty.bin");
         assertThrows(UnsupportedEncodingException.class,
             () -> new ReversedLinesFileReader(testFileEncodingBig5, IOUtils.DEFAULT_BUFFER_SIZE, "Big5").close());
     }
 
     @Test
     void testUnsupportedEncodingUTF16() throws URISyntaxException {
         final File testFileEmpty = TestResources.getFile("/test-file-empty.bin");
         assertThrows(UnsupportedEncodingException.class,
             () -> new ReversedLinesFileReader(testFileEmpty, IOUtils.DEFAULT_BUFFER_SIZE, StandardCharsets.UTF_16.name()).close());
     }
 }