/*

 * 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 jdk.internal.jline;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import jdk.internal.jline.internal.Log;

import jdk.internal.jline.internal.ShutdownHooks;

import jdk.internal.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;

    }

}