/**
    * Logback: the reliable, generic, fast and flexible logging framework.
    * Copyright (C) 1999-2015, QOS.ch. All rights reserved.
    *
    * This program and the accompanying materials are dual-licensed under
    * either the terms of the Eclipse Public License v1.0 as published by
    * the Eclipse Foundation
    *
    *   or (per the licensee's choosing)
   *
   * under the terms of the GNU Lesser General Public License version 2.1
   * as published by the Free Software Foundation.
   */
  package ch.qos.logback.core;
  
  import java.io.OutputStream;
  import java.io.PrintStream;
  import java.lang.reflect.Method;
  import java.lang.reflect.Modifier;
  import java.util.Arrays;
  import java.util.NoSuchElementException;
  import java.util.Optional;
  
  import ch.qos.logback.core.joran.spi.ConsoleTarget;
  import ch.qos.logback.core.status.Status;
  import ch.qos.logback.core.status.WarnStatus;
  import ch.qos.logback.core.util.Loader;
  
  /**
   * ConsoleAppender appends log events to <code>System.out</code> or
   * <code>System.err</code> using a layout specified by the user. The default
   * target is <code>System.out</code>.
   * <p>
   * &nbsp;
   * </p>
   * For more information about this appender, please refer to the online manual
   * at http://logback.qos.ch/manual/appenders.html#ConsoleAppender
   *
   * @author Ceki G&uuml;lc&uuml;
   * @author Tom SH Liu
   * @author Ruediger Dohna
   */
  
  public class ConsoleAppender<E> extends OutputStreamAppender<E> {
  
      protected ConsoleTarget target = ConsoleTarget.SystemOut;
      protected boolean withJansi = false;
  
      private final static String AnsiConsole_CLASS_NAME = "org.fusesource.jansi.AnsiConsole";
      private final static String JANSI2_OUT_METHOD_NAME = "out";
      private final static String JANSI2_ERR_METHOD_NAME = "err";
      private final static String wrapSystemOut_METHOD_NAME = "wrapSystemOut";
      private final static String wrapSystemErr_METHOD_NAME = "wrapSystemErr";
      private final static Class<?>[] ARGUMENT_TYPES = { PrintStream.class };
  
      /**
       * Sets the value of the <b>Target</b> option. Recognized values are
       * "System.out" and "System.err". Any other value will be ignored.
       */
      public void setTarget(String value) {
          ConsoleTarget t = ConsoleTarget.findByName(value.trim());
          if (t == null) {
              targetWarn(value);
          } else {
              target = t;
          }
      }
  
      /**
       * Returns the current value of the <b>target</b> property. The default value of
       * the option is "System.out".
       * <p>
       * See also {@link #setTarget}.
       */
      public String getTarget() {
          return target.getName();
      }
  
      private void targetWarn(String val) {
          Status status = new WarnStatus("[" + val + "] should be one of " + Arrays.toString(ConsoleTarget.values()),
                  this);
          status.add(new WarnStatus("Using previously set target, System.out by default.", this));
          addStatus(status);
      }
  
      @Override
      public void start() {
          OutputStream targetStream = target.getStream();
          // enable jansi only if withJansi set to true
          if (withJansi) {
              targetStream = wrapWithJansi(targetStream);
          }
          setOutputStream(targetStream);
          super.start();
      }
  
      private OutputStream wrapWithJansi(OutputStream targetStream) {
          try {
              addInfo("Enabling JANSI AnsiPrintStream for the console.");
             ClassLoader classLoader = Loader.getClassLoaderOfObject(context);
             Class<?> classObj = classLoader.loadClass(AnsiConsole_CLASS_NAME);
 
             // check for JAnsi 2
             String methodNameJansi2 = target == ConsoleTarget.SystemOut ? JANSI2_OUT_METHOD_NAME
                     : JANSI2_ERR_METHOD_NAME;
             final Optional<Method> optOutMethod = Arrays.stream(classObj.getMethods())
                     .filter(m -> m.getName().equals(methodNameJansi2))
                     .filter(m -> m.getParameters().length == 0)
                     .filter(m -> Modifier.isStatic(m.getModifiers()))
                     .filter(m -> PrintStream.class.isAssignableFrom(m.getReturnType()))
                     .findAny();
             if (optOutMethod.isPresent()) {
                 final Method outMethod = optOutMethod.orElseThrow(() -> new NoSuchElementException("No value present"));
                 return (PrintStream) outMethod.invoke(null);
             }
 
             // JAnsi 1
             String methodName = target == ConsoleTarget.SystemOut ? wrapSystemOut_METHOD_NAME
                     : wrapSystemErr_METHOD_NAME;
             Method method = classObj.getMethod(methodName, ARGUMENT_TYPES);
             return (OutputStream) method.invoke(null, new PrintStream(targetStream));
         } catch (Exception e) {
             addWarn("Failed to create AnsiPrintStream. Falling back on the default stream.", e);
         }
         return targetStream;
     }
 
     /**
      * @return whether to use JANSI or not.
      */
     public boolean isWithJansi() {
         return withJansi;
     }
 
     /**
      * If true, this appender will output to a stream provided by the JANSI library.
      *
      * @param withJansi whether to use JANSI or not.
      * @since 1.0.5
      */
     public void setWithJansi(boolean withJansi) {
         this.withJansi = withJansi;
     }
 
 }