/*
    * 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.configuration2;
  
  import static org.apache.commons.configuration2.TempDirUtils.newFile;
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  
  import java.io.File;
  import java.io.IOException;
  import java.util.Iterator;
  import java.util.Properties;
  import java.util.concurrent.atomic.AtomicBoolean;
  
  import org.apache.commons.configuration2.ex.ConfigurationException;
  import org.apache.commons.configuration2.io.FileHandler;
  import org.junit.jupiter.api.Test;
  import org.junit.jupiter.api.io.TempDir;
  
  /**
   * Tests for {@code SystemConfiguration}.
   */
  public class TestSystemConfiguration {
      /** A folder for temporary files. */
      @TempDir
      public File tempFolder;
  
      /**
       * Tests an append operation with a system configuration while system properties are modified from another thread. This
       * is related to CONFIGURATION-570.
       */
      @Test
      public void testAppendWhileConcurrentAccess() throws InterruptedException {
          final AtomicBoolean stop = new AtomicBoolean();
          final String property = SystemConfiguration.class.getName() + ".testProperty";
          final Thread t = new Thread(() -> {
              boolean setValue = true;
              while (!stop.get()) {
                  if (setValue) {
                      System.setProperty(property, "true");
                  } else {
                      System.clearProperty(property);
                  }
                  setValue = !setValue;
              }
          });
          try {
              t.start();
  
              final SystemConfiguration config = new SystemConfiguration();
              final PropertiesConfiguration props = new PropertiesConfiguration();
              props.append(config);
  
              stop.set(true);
              t.join();
              for (final Iterator<String> keys = config.getKeys(); keys.hasNext();) {
                  final String key = keys.next();
                  if (!property.equals(key)) {
                      assertEquals(config.getString(key), props.getString(key), "Wrong value for " + key);
                  }
              }
          } finally {
              System.clearProperty(property);
          }
      }
  
      /**
       * Tests whether the configuration can be used to change system properties.
       */
      @Test
      public void testChangeSystemProperties() {
          final String testProperty = "someTest";
          final SystemConfiguration config = new SystemConfiguration();
          config.setProperty(testProperty, "true");
          assertEquals("true", System.getProperty(testProperty));
      }
  
      @Test
      public void testSetSystemProperties() {
          final PropertiesConfiguration props = new PropertiesConfiguration();
          props.addProperty("test.name", "Apache");
          SystemConfiguration.setSystemProperties(props);
          assertEquals("Apache", System.getProperty("test.name"));
      }
 
     /**
      * Tests whether system properties can be set from a configuration file.
      */
     @Test
     public void testSetSystemPropertiesFromPropertiesFile() throws ConfigurationException, IOException {
         final File file = newFile("sys.properties", tempFolder);
         final PropertiesConfiguration pconfig = new PropertiesConfiguration();
         final FileHandler handler = new FileHandler(pconfig);
         pconfig.addProperty("fromFile", Boolean.TRUE);
         handler.setFile(file);
         handler.save();
         SystemConfiguration.setSystemProperties(handler.getBasePath(), handler.getFileName());
         final SystemConfiguration sconf = new SystemConfiguration();
         assertTrue(sconf.getBoolean("fromFile"));
     }
 
     @Test
     public void testSystemConfiguration() {
         final Properties props = System.getProperties();
         props.put("test.number", "123");
 
         final Configuration conf = new SystemConfiguration();
         assertEquals(123, conf.getInt("test.number"));
     }
 }