/*
 * 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.geode.management.internal.cli.shell;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNull;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.PrintStream;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Handler;
import java.util.logging.LogRecord;

import org.apache.commons.io.FileUtils;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.core.LoggerContext;
import org.apache.logging.log4j.core.config.ConfigurationFactory;
import org.junit.After;
import org.junit.AfterClass;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.ClassRule;
import org.junit.Rule;
import org.junit.Test;
import org.junit.contrib.java.lang.system.RestoreSystemProperties;
import org.junit.rules.TemporaryFolder;

import org.apache.geode.management.internal.cli.LogWrapper;

/**
 * Unit tests for supplying an init file to Gfsh.
 * </P>
 * Makes use of reflection to reset private static variables on some classes to replace loggers that
 * would otherwise clutter the console.
 */
public class GfshInitFileJUnitTest {

  private static final String INIT_FILE_NAME = GfshConfig.DEFAULT_INIT_FILE_NAME;
  private static final boolean APPEND = true;
  private static final int BANNER_LINES = 1;
  private static final int INIT_FILE_CITATION_LINES = 1;

  private static String saveLog4j2Config;
  private static java.util.logging.Logger julLogger;
  private static Handler[] saveHandlers;

  private ByteArrayOutputStream sysout = new ByteArrayOutputStream();
  private String gfshHistoryFileName;
  private LogWrapper gfshFileLogger;
  private JUnitLoggerHandler junitLoggerHandler;

  @ClassRule
  public static TemporaryFolder temporaryFolder_Config = new TemporaryFolder();

  @Rule
  public TemporaryFolder temporaryFolder_CurrentDirectory = new TemporaryFolder();

  @Rule
  public RestoreSystemProperties restoreSystemProperties = new RestoreSystemProperties();

  /*
   * Turn off console logging from JUL and Log4j2 for the duration of this class's tests, to reduce
   * noise level of output in automated build.
   */
  @BeforeClass
  public static void setUpBeforeClass() throws Exception {
    saveLog4j2Config = System.getProperty(ConfigurationFactory.CONFIGURATION_FILE_PROPERTY);

    julLogger = java.util.logging.Logger.getLogger("");
    saveHandlers = julLogger.getHandlers();
    for (Handler handler : saveHandlers) {
      julLogger.removeHandler(handler);
    }

    File log4j2XML = temporaryFolder_Config.newFile("log4j2.xml");
    FileUtils.writeStringToFile(log4j2XML, "<Configuration/>", APPEND);
    System.setProperty(ConfigurationFactory.CONFIGURATION_FILE_PROPERTY,
        log4j2XML.toURI().toString());
  }

  /*
   * Restore logging to state prior to the execution of this class
   */
  @AfterClass
  public static void tearDownAfterClass() throws Exception {
    for (Handler handler : saveHandlers) {
      julLogger.addHandler(handler);
    }

    if (saveLog4j2Config == null) {
      System.clearProperty(ConfigurationFactory.CONFIGURATION_FILE_PROPERTY);
    } else {
      System.setProperty(ConfigurationFactory.CONFIGURATION_FILE_PROPERTY, saveLog4j2Config);
      ((LoggerContext) LogManager.getContext(false)).reconfigure();
    }

    Gfsh.getCurrentInstance().stop();
  }

  @Before
  public void setUp() throws Exception {

    // Null out static instance so can reinitialise
    Field gfsh_instance = Gfsh.class.getDeclaredField("instance");
    gfsh_instance.setAccessible(true);
    gfsh_instance.set(null, null);

    this.junitLoggerHandler = new JUnitLoggerHandler();

    this.gfshFileLogger = LogWrapper.getInstance(null);
    Field logWrapper_INSTANCE = LogWrapper.class.getDeclaredField("INSTANCE");
    logWrapper_INSTANCE.setAccessible(true);
    logWrapper_INSTANCE.set(null, this.gfshFileLogger);

    Field logWrapper_logger = LogWrapper.class.getDeclaredField("logger");
    logWrapper_logger.setAccessible(true);
    julLogger.addHandler(this.junitLoggerHandler);
    logWrapper_logger.set(this.gfshFileLogger, julLogger);

    Gfsh.gfshout = new PrintStream(sysout);
    this.gfshHistoryFileName =
        temporaryFolder_CurrentDirectory.newFile("historyFile").getAbsolutePath();
  }

  @After
  public void tearDown() throws Exception {
    julLogger.removeHandler(this.junitLoggerHandler);
  }

  @Test
  public void testInitFile_NotProvided() throws Exception {
    /*
     * String historyFileName, String defaultPrompt, int historySize, String logDir, Level logLevel,
     * Integer logLimit, Integer logCount, String initFileName
     */
    GfshConfig gfshConfig = new GfshConfig(this.gfshHistoryFileName, "", 0,
        temporaryFolder_CurrentDirectory.getRoot().getAbsolutePath(), null, null, null, null);
    assertNull(INIT_FILE_NAME, gfshConfig.getInitFileName());

    /*
     * boolean launchShell, String[] args, GfshConfig gfshConfig
     */
    Gfsh gfsh = Gfsh.getInstance(false, new String[] {}, gfshConfig);

    int actualStatus = gfsh.getLastExecutionStatus();
    int expectedStatus = 0;
    assertEquals("Status 0==success", expectedStatus, actualStatus);

    int expectedLogCount = BANNER_LINES;
    assertEquals("Log records written", expectedLogCount, this.junitLoggerHandler.getLog().size());
    for (LogRecord logRecord : this.junitLoggerHandler.getLog()) {
      assertNull("No exceptions in log", logRecord.getThrown());
    }
  }

  @Test
  public void testInitFile_NotFound() throws Exception {
    // Construct the file name but not the file
    String initFileName = temporaryFolder_CurrentDirectory.getRoot().getAbsolutePath()
        + File.separator + INIT_FILE_NAME;

    /*
     * String historyFileName, String defaultPrompt, int historySize, String logDir, Level logLevel,
     * Integer logLimit, Integer logCount, String initFileName
     */
    GfshConfig gfshConfig = new GfshConfig(this.gfshHistoryFileName, "", 0,
        temporaryFolder_CurrentDirectory.getRoot().getAbsolutePath(), null, null, null,
        initFileName);
    assertNotNull(INIT_FILE_NAME, gfshConfig.getInitFileName());

    /*
     * boolean launchShell, String[] args, GfshConfig gfshConfig
     */
    Gfsh gfsh = Gfsh.getInstance(false, new String[] {}, gfshConfig);

    int actualStatus = gfsh.getLastExecutionStatus();
    int expectedStatus = 0;
    assertNotEquals("Status <0==failure", expectedStatus, actualStatus);

    int expectedLogCount = BANNER_LINES + INIT_FILE_CITATION_LINES + 1;
    assertEquals("Log records written", expectedLogCount, this.junitLoggerHandler.getLog().size());
    Throwable exception = null;
    for (LogRecord logRecord : this.junitLoggerHandler.getLog()) {
      if (logRecord.getThrown() != null) {
        exception = logRecord.getThrown();
        break;
      }
    }
    assertNotNull("Exceptions in log", exception);
  }

  @Test
  public void testInitFile_Empty() throws Exception {
    File initFile = temporaryFolder_CurrentDirectory.newFile(INIT_FILE_NAME);

    /*
     * String historyFileName, String defaultPrompt, int historySize, String logDir, Level logLevel,
     * Integer logLimit, Integer logCount, String initFileName
     */
    GfshConfig gfshConfig = new GfshConfig(this.gfshHistoryFileName, "", 0,
        temporaryFolder_CurrentDirectory.getRoot().getAbsolutePath(), null, null, null,
        initFile.getAbsolutePath());
    assertNotNull(INIT_FILE_NAME, gfshConfig.getInitFileName());

    /*
     * boolean launchShell, String[] args, GfshConfig gfshConfig
     */
    Gfsh gfsh = Gfsh.getInstance(false, new String[] {}, gfshConfig);

    int actualStatus = gfsh.getLastExecutionStatus();
    int expectedStatus = 0;
    assertEquals("Status 0==success", expectedStatus, actualStatus);

    int expectedLogCount = BANNER_LINES + INIT_FILE_CITATION_LINES + 1;
    assertEquals("Log records written", expectedLogCount, this.junitLoggerHandler.getLog().size());
    for (LogRecord logRecord : this.junitLoggerHandler.getLog()) {
      assertNull("No exceptions in log", logRecord.getThrown());
    }
  }

  @Test
  public void testInitFile_OneGoodCommand() throws Exception {
    File initFile = temporaryFolder_CurrentDirectory.newFile(INIT_FILE_NAME);
    FileUtils.writeStringToFile(initFile, "echo --string=hello" + Gfsh.LINE_SEPARATOR, APPEND);

    /*
     * String historyFileName, String defaultPrompt, int historySize, String logDir, Level logLevel,
     * Integer logLimit, Integer logCount, String initFileName
     */
    GfshConfig gfshConfig = new GfshConfig(this.gfshHistoryFileName, "", 0,
        temporaryFolder_CurrentDirectory.getRoot().getAbsolutePath(), null, null, null,
        initFile.getAbsolutePath());
    assertNotNull(INIT_FILE_NAME, gfshConfig.getInitFileName());

    /*
     * boolean launchShell, String[] args, GfshConfig gfshConfig
     */
    Gfsh gfsh = Gfsh.getInstance(false, new String[] {}, gfshConfig);

    int actualStatus = gfsh.getLastExecutionStatus();
    int expectedStatus = 0;
    assertEquals("Status 0==success", expectedStatus, actualStatus);

    int expectedLogCount = BANNER_LINES + INIT_FILE_CITATION_LINES + 1;
    assertEquals("Log records written", expectedLogCount, this.junitLoggerHandler.getLog().size());
    for (LogRecord logRecord : this.junitLoggerHandler.getLog()) {
      assertNull("No exceptions in log", logRecord.getThrown());
    }
  }

  @Test
  public void testInitFile_TwoGoodCommands() throws Exception {
    File initFile = temporaryFolder_CurrentDirectory.newFile(INIT_FILE_NAME);
    FileUtils.writeStringToFile(initFile, "echo --string=hello" + Gfsh.LINE_SEPARATOR, APPEND);
    FileUtils.writeStringToFile(initFile, "echo --string=goodbye" + Gfsh.LINE_SEPARATOR, APPEND);

    /*
     * String historyFileName, String defaultPrompt, int historySize, String logDir, Level logLevel,
     * Integer logLimit, Integer logCount, String initFileName
     */
    GfshConfig gfshConfig = new GfshConfig(this.gfshHistoryFileName, "", 0,
        temporaryFolder_CurrentDirectory.getRoot().getAbsolutePath(), null, null, null,
        initFile.getAbsolutePath());
    assertNotNull(INIT_FILE_NAME, gfshConfig.getInitFileName());

    /*
     * boolean launchShell, String[] args, GfshConfig gfshConfig
     */
    Gfsh gfsh = Gfsh.getInstance(false, new String[] {}, gfshConfig);

    int actualStatus = gfsh.getLastExecutionStatus();
    int expectedStatus = 0;
    assertEquals("Status 0==success", expectedStatus, actualStatus);

    int expectedLogCount = BANNER_LINES + INIT_FILE_CITATION_LINES + 1;
    assertEquals("Log records written", expectedLogCount, this.junitLoggerHandler.getLog().size());
    for (LogRecord logRecord : this.junitLoggerHandler.getLog()) {
      assertNull("No exceptions in log", logRecord.getThrown());
    }
  }

  @Test
  public void testInitFile_OneBadCommand() throws Exception {
    File initFile = temporaryFolder_CurrentDirectory.newFile(INIT_FILE_NAME);
    FileUtils.writeStringToFile(initFile, "fail" + Gfsh.LINE_SEPARATOR, APPEND);

    /*
     * String historyFileName, String defaultPrompt, int historySize, String logDir, Level logLevel,
     * Integer logLimit, Integer logCount, String initFileName
     */
    GfshConfig gfshConfig = new GfshConfig(this.gfshHistoryFileName, "", 0,
        temporaryFolder_CurrentDirectory.getRoot().getAbsolutePath(), null, null, null,
        initFile.getAbsolutePath());
    assertNotNull(INIT_FILE_NAME, gfshConfig.getInitFileName());

    /*
     * boolean launchShell, String[] args, GfshConfig gfshConfig
     */
    Gfsh gfsh = Gfsh.getInstance(false, new String[] {}, gfshConfig);

    int actualStatus = gfsh.getLastExecutionStatus();
    int expectedStatus = 0;
    assertNotEquals("Status <0==failure", expectedStatus, actualStatus);

    // after upgrading to Spring-shell 1.2, the bad command exception is logged as well
    int expectedLogCount = BANNER_LINES + INIT_FILE_CITATION_LINES + 2;
    assertEquals("Log records written", expectedLogCount, this.junitLoggerHandler.getLog().size());
  }

  @Test
  public void testInitFile_TwoBadCommands() throws Exception {
    File initFile = temporaryFolder_CurrentDirectory.newFile(INIT_FILE_NAME);
    FileUtils.writeStringToFile(initFile, "fail" + Gfsh.LINE_SEPARATOR, APPEND);
    FileUtils.writeStringToFile(initFile, "fail" + Gfsh.LINE_SEPARATOR, APPEND);

    /*
     * String historyFileName, String defaultPrompt, int historySize, String logDir, Level logLevel,
     * Integer logLimit, Integer logCount, String initFileName
     */
    GfshConfig gfshConfig = new GfshConfig(this.gfshHistoryFileName, "", 0,
        temporaryFolder_CurrentDirectory.getRoot().getAbsolutePath(), null, null, null,
        initFile.getAbsolutePath());
    assertNotNull(INIT_FILE_NAME, gfshConfig.getInitFileName());

    /*
     * boolean launchShell, String[] args, GfshConfig gfshConfig
     */
    Gfsh gfsh = Gfsh.getInstance(false, new String[] {}, gfshConfig);

    int actualStatus = gfsh.getLastExecutionStatus();
    int expectedStatus = 0;
    assertNotEquals("Status <0==failure", expectedStatus, actualStatus);

    // after upgrading to Spring-shell 1.2, the bad command exception is logged as well
    int expectedLogCount = BANNER_LINES + INIT_FILE_CITATION_LINES + 2;
    assertEquals("Log records written", expectedLogCount, this.junitLoggerHandler.getLog().size());
  }

  @Test
  public void testInitFile_BadAndGoodCommands() throws Exception {
    File initFile = temporaryFolder_CurrentDirectory.newFile(INIT_FILE_NAME);
    FileUtils.writeStringToFile(initFile, "fail" + Gfsh.LINE_SEPARATOR, APPEND);
    FileUtils.writeStringToFile(initFile, "echo --string=goodbye" + Gfsh.LINE_SEPARATOR, APPEND);

    /*
     * String historyFileName, String defaultPrompt, int historySize, String logDir, Level logLevel,
     * Integer logLimit, Integer logCount, String initFileName
     */
    GfshConfig gfshConfig = new GfshConfig(this.gfshHistoryFileName, "", 0,
        temporaryFolder_CurrentDirectory.getRoot().getAbsolutePath(), null, null, null,
        initFile.getAbsolutePath());
    assertNotNull(INIT_FILE_NAME, gfshConfig.getInitFileName());

    /*
     * boolean launchShell, String[] args, GfshConfig gfshConfig
     */
    Gfsh gfsh = Gfsh.getInstance(false, new String[] {}, gfshConfig);

    int actualStatus = gfsh.getLastExecutionStatus();
    int expectedStatus = 0;
    assertNotEquals("Status <0==failure", expectedStatus, actualStatus);

    // after upgrading to Spring-shell 1.2, the bad command exception is logged as well
    int expectedLogCount = BANNER_LINES + INIT_FILE_CITATION_LINES + 2;
    assertEquals("Log records written", expectedLogCount, this.junitLoggerHandler.getLog().size());
  }

  /**
   * Log handler for testing. Capture logged messages for later inspection.
   *
   * @see java.util.logging.Handler#publish(java.util.logging.LogRecord)
   */
  private static class JUnitLoggerHandler extends Handler {

    private List<LogRecord> log;

    public JUnitLoggerHandler() {
      log = new ArrayList<>();
    }

    public List<LogRecord> getLog() {
      return log;
    }

    @Override
    public void publish(LogRecord record) {
      log.add(record);
    }

    @Override
    public void flush() {}

    @Override
    public void close() throws SecurityException {}
  }
}