//==============================================================================
// CommandNode.java
//==============================================================================

package tribble.net.ftp.shell;

import java.io.IOException;
import java.io.PrintWriter;

import java.lang.Exception;
import java.lang.Integer;
import java.lang.String;


/*******************************************************************************
* FTP command script parser.
*
* <!--~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-->
* <p>
* <b> Example </b>
*
* <pre>
*  loop1:
*    foreach remote *.tar do begin
*        get $F
*        if $_E != 0
*            continue loop1
*        del $F
*        !tar -xf $F
*        !del $F
*    end</pre>
*
* <p>
* The example script above parses into the following command parse tree:
* <pre>
*    1  (label "loop1")
*    2  (foreach "remote" "*.tar")
*    3      (get "$F")
*    4      (if (!= "$_E" "0"))
*    5          (continue 2 "loop1")
*    6      (del "$F")
*    7      (! "tar" "-xf" "$F")
*    8      (! "del" "$F")</pre>
*
* <!--~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-->
* @version	API 1.1 $Revision: 1.9 $ $Date: 2010/07/12 23:27:13 $
* @since	API 1.0, 2007-03-11
* @author	David R. Tribble (david&#64;tribble.com).
*	<p>
*	Copyright ©2007-2010 by David R. Tribble, all rights reserved.<br>
*	Permission is granted to any person or entity except those designated by
*	by the United States Department of State as a terrorist, or terrorist
*	government or agency, to use and distribute this source code provided
*	that the original copyright notice remains present and unaltered.
*
* @see	CommandParser
*/

class CommandNode
    implements CommandCodes
{
    /** Revision information. */
    static final String		REV =
        "@(#)tribble/net/ftp/shell/CommandNode.java API 1.1 $Revision: 1.9 $ $Date: 2010/07/12 23:27:13 $\n";


// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// Variables

    /** Command operator. */
    String		m_cmd =		CMD__UNDEF;

    /** Arguments (may be null).
    * Each argument is one of these types:<br>
    * - <tt>String</tt>, containing a name, word token, or literal value;<br>
    * - <tt>CommandNode</tt>, containing a subexpression;<br>
    * - <tt>BlockDef</tt>, containing a begin/end block or func definition.
    */
    Object[]		m_args;

    /** Next command. */
    CommandNode		m_next;

    /** Source line number. */
    int			m_lineNo;


// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// Constructors

    /***************************************************************************
    * Constructor.
    *
    * @param	cmd
    * Command code, one of the {@link #CMD__UNDEF CMD_<i>XXX</i>} constants.
    *
    * @param	line
    * Source line number for this command node.
    *
    * @since	1.2, 2007-03-13
    */
    CommandNode(String cmd, int line)
    {
        m_cmd = cmd;
        m_lineNo = line;
    }


// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// Methods

    /***************************************************************************
    * Append an argument to this command node.
    *
    * @param	arg
    * An argument (usually a <tt>String</tt> or another {@link CommandNode}
    * subtree).
    *
    * @since	1.1, 2007-03-11
    */
    int addArg(Object arg)
    {
        int	n;

        // Expand the argument array
        if (m_args != null)
        {
            Object[]	old;

            old = m_args;
            n = old.length;
            m_args = new Object[n+1];
            for (int i = 0;  i < n;  i++)
                m_args[i] = old[i];
        }
        else
        {
            m_args = new Object[1];
            n = 0;
        }

        m_args[n] = arg;
        return (n+1);
    }


    /***************************************************************************
    * Pretty-print this parse tree.
    *
    * @since	1.2, 2007-03-13
    */
    void print(PrintWriter out)
    {
        CommandNode	n;

        if (out == null)
            return;

        for (n = this;  n != null;  n = n.m_next)
            n.printTree(out, "", -1);
    }


    /***************************************************************************
    * Pretty-print this parse tree.
    * This is a helper method.
    *
    * @since	1.2, 2007-03-13
    */
    private void printTree(PrintWriter out, String indent, int lineNo)
    {
        if (m_lineNo != lineNo)
            out.println(m_lineNo + ":");
        out.println(indent + "(" + m_cmd + ")");

        if (m_args != null)
        {
            for (int i = 0;  i < m_args.length;  i++)
            {
                Object	arg;

                arg = m_args[i];
                if (arg instanceof CommandNode)
                {
                    CommandNode		n;

                    n = (CommandNode) arg;
                    if (m_cmd == CMD_LABEL  ||  m_cmd == CMD_GOTO  ||
                        m_cmd == CMD_BREAK  ||  m_cmd == CMD_CONTINUE)
                    {
                        out.print(indent + "  -> ");
                        out.print(n.m_cmd);
                        out.print(" @");
                        out.println(n.m_lineNo);
                    }
                    else
                    {
                        for ( ;  n != null;  n = n.m_next)
                            n.printTree(out, indent + "  ", m_lineNo);
                    }
                }
                else
                {
                    out.print(indent);
                    out.print("  ");

                    if (arg == null)
                        out.println("nil");
                    else if (arg instanceof String)
                    {
                        String	s;
                        char	ch;

                        s = (String) arg;
                        ch = s.charAt(0);
                        if (ch == 's'  ||  ch == 'n')
                        {
                            // Note: This is not exactly correct,
                            //  but it's good enough for debugging purposes
                            out.print(ch);
                        }
                        else
                            s = 's' + s;
                        ExecFrame.dumpString(s, out);
                        out.println();
                    }
                    else if (arg instanceof Integer)
                    {
                        int	n;

                        n = ((Integer) arg).intValue();
                        if (n >= 0)
                            out.print('+');
                        out.println(n);
                    }
                    else if (arg instanceof BlockDef)
                    {
                        BlockDef	def;

                        def = (BlockDef) arg;
                        out.print("{\"");
                        out.print(def.m_name);
                        out.print("\" ");
                        out.print(def.m_type);
                        out.println("}");
                    }
                    else
                        out.println("<" + arg.getClass().getName() + ">");
                }
            }
        }
    }
}

// End CommandNode.java