/*
    * 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.lang3;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  
  import java.io.IOException;
  import java.nio.charset.Charset;
  import java.nio.file.Files;
  import java.nio.file.Path;
  import java.util.UUID;
  
  import org.junit.jupiter.api.io.TempDir;
  import org.junit.jupiter.params.ParameterizedTest;
  import org.junit.jupiter.params.provider.Arguments;
  import org.junit.jupiter.params.provider.MethodSource;
  
  /**
   * Tests {@link RuntimeEnvironment}.
   */
  class RuntimeEnvironmentTest {
  
      private static final String simpleEnviron = "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin\u0000" +
              "HOSTNAME=d62718b69f37\u0000TERM=xterm\u0000HOME=/root\u0000";
  
      private static final String podmanEnviron = "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin\u0000" +
              "HOSTNAME=d62718b69f37\u0000TERM=xterm\u0000container=podman\u0000HOME=/root\u0000";
  
      private static final String emptyContainer = "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin\u0000" +
              "HOSTNAME=d62718b69f37\u0000TERM=xterm\u0000container=\u0000HOME=/root\u0000";
  
      private static Arguments[] testIsContainer() {
          return new Arguments[]{
                  Arguments.of("in docker no file", simpleEnviron, null, false),
                  Arguments.of("in docker with file", simpleEnviron, ".dockerenv", true),
                  Arguments.of("in podman no file", podmanEnviron, "run/.containerenv", true),
                  Arguments.of("in podman with file", simpleEnviron, "run/.containerenv", true),
                  Arguments.of("in podman empty env var no file", emptyContainer, null, false),
                  Arguments.of("in podman empty env var with file", emptyContainer, "run/.containerenv", false),
                  Arguments.of("not in container", simpleEnviron, null, false),
                  Arguments.of("pid1 error no file", null, null, false),
                  Arguments.of("pid1 error docker file", null, ".dockerenv", true),
                  Arguments.of("pid1 error podman file", null, ".dockerenv", true),
          };
      }
  
      @TempDir
      private Path tempDir;
  
      private boolean doTestInContainer(final String environ, final String fileToCreate) throws IOException {
          final Path testDir = tempDir.resolve(UUID.randomUUID().toString());
          final Path pid1EnvironFile = testDir.resolve("proc/1/environ");
          Files.createDirectories(pid1EnvironFile.getParent());
          if (fileToCreate != null) {
              final Path file = testDir.resolve(fileToCreate);
              Files.createDirectories(file.getParent());
              Files.createFile(file);
          }
          if (environ != null) {
              Files.write(pid1EnvironFile, environ.getBytes(Charset.defaultCharset()));
          }
          return RuntimeEnvironment.inContainer(testDir.toString());
      }
  
      @ParameterizedTest
      @MethodSource
      void testIsContainer(final String label, final String environ, final String fileToCreate, final boolean expected) throws IOException {
          assertEquals(expected, doTestInContainer(environ, fileToCreate), label);
      }
  }