/*
    * Copyright (c) 2002-2012, the original author or authors.
    *
    * This software is distributable under the BSD license. See the terms of the
    * BSD license in the documentation provided with this software.
    *
    * http://www.opensource.org/licenses/bsd-license.php
    */
   package jline;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  
  import jline.internal.Log;
  import jline.internal.ShutdownHooks;
  import jline.internal.ShutdownHooks.Task;
  
  /**
   * Provides support for {@link Terminal} instances.
   *
   * @author <a href="mailto:jason@planet57.com">Jason Dillon</a>
   * @since 2.0
   */
  public abstract class TerminalSupport
      implements Terminal
  {
      public static final int DEFAULT_WIDTH = 80;
  
      public static final int DEFAULT_HEIGHT = 24;
  
      private Task shutdownTask;
  
      private boolean supported;
  
      private boolean echoEnabled;
  
      private boolean ansiSupported;
  
      protected TerminalSupport(final boolean supported) {
          this.supported = supported;
      }
  
      public void init() throws Exception {
          if (shutdownTask != null) {
              ShutdownHooks.remove(shutdownTask);
          }
          // Register a task to restore the terminal on shutdown
          this.shutdownTask = ShutdownHooks.add(new Task()
          {
              public void run() throws Exception {
                  restore();
              }
          });
      }
  
      public void restore() throws Exception {
          TerminalFactory.resetIf(this);
          if (shutdownTask != null) {
            ShutdownHooks.remove(shutdownTask);
            shutdownTask = null;
          }
      }
  
      public void reset() throws Exception {
          restore();
          init();
      }
  
      public final boolean isSupported() {
          return supported;
      }
  
      public synchronized boolean isAnsiSupported() {
          return ansiSupported;
      }
  
      protected synchronized void setAnsiSupported(final boolean supported) {
          this.ansiSupported = supported;
          Log.debug("Ansi supported: ", supported);
      }
  
      /**
       * Subclass to change behavior if needed.
       * @return the passed out
       */
      public OutputStream wrapOutIfNeeded(OutputStream out) {
          return out;
      }
  
      /**
       * Defaults to true which was the behaviour before this method was added.
       */
      public boolean hasWeirdWrap() {
          return true;
      }
  
      public int getWidth() {
          return DEFAULT_WIDTH;
     }
 
     public int getHeight() {
         return DEFAULT_HEIGHT;
     }
 
     public synchronized boolean isEchoEnabled() {
         return echoEnabled;
     }
 
     public synchronized void setEchoEnabled(final boolean enabled) {
         this.echoEnabled = enabled;
         Log.debug("Echo enabled: ", enabled);
     }
 
     public InputStream wrapInIfNeeded(InputStream in) throws IOException {
         return in;
     }
 
     public String getOutputEncoding() {
         // null for unknown
         return null;
     }
 }