//==============================================================================
// BlockDef.java
//==============================================================================

package tribble.net.ftp.shell;

import java.io.PrintWriter;

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

import java.util.HashMap;


/*******************************************************************************
* FTP command begin/end block or func definition.
*
* <!--~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-->
* @version	API 1.1 $Revision: 1.10 $ $Date: 2010/07/12 22:29:52 $
* @since	API 1.0, 2007-03-16
* @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	CommandExec
* @see	ExecFrame
*/

class BlockDef
    implements CommandCodes
{
    /** Revision information. */
    static final String		REV =
        "@(#)tribble/net/ftp/shell/BlockDef.java API 1.1 $Revision: 1.10 $ $Date: 2010/07/12 22:29:52 $\n";


// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// Constants

    //----------------------------------------
    // Locally defined name types

    private static final short		NAMETYPE_VAR =		1;
    private static final short		NAMETYPE_LABEL =	2;
    private static final short		NAMETYPE_FUNC =		3;


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

    /** Name of this block definition. */
    String			m_name;

    /** Block type (<tt>begin/end</tt>, <tt>foreach</tt>, <tt>repeat</tt>). */
    String			m_type;

    /** Outer block containing this block definition. */
    BlockDef			m_outer;

    /** Parent command enclosing this block. */
    CommandNode			m_parent;

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

    /** Scope nesting depth. */
    int				m_depth;

    /** Commands (statements) in this block definition. */
    private CommandNode		m_cmds;

    /** Local func definitions. */
    private HashMap<String, CommandNode>
				m_funcs;

    /** Local var definitions. */
    private HashMap<String, CommandNode>
				m_vars;

    /** Local statement label definitions. */
    private HashMap<String, CommandNode>
				m_labels;


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

    /***************************************************************************
    * Constructor.
    *
    * @param	name
    * Name of this block.  Funcs have user-defined names, while begin/end block
    * have names such as <tt>".42"</tt>.
    *
    * @param	lineNo
    * Source line number where the block is defined.
    *
    * @param	outer
    * Begin/end block or func containing this block.  This is null for the
    * outermost (file) scope, which has no outer scope.
    *
    * @param	cmd
    * Parent command containing this block.  This is null for the outermost
    * (file) scope, and for block commands having no controlling command.
    *
    * @since	1.7, 2007-08-02
    */
    BlockDef(String name, int lineNo, BlockDef outer, CommandNode cmd)
    {
        // Initialize
        m_name =   name;
        m_lineNo = lineNo;
        m_outer =  outer;
        m_parent = cmd;

        // Set up
        if (outer != null)
            m_depth = outer.m_depth+1;
    }


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

    /***************************************************************************
    * Establish the commands (statements) for this block definition.
    *
    * @param	cmds
    * First command (statement) defined within the begin/end block or func, or
    * null if there are no commands.
    *
    * @since	1.1, 2007-03-16
    */
    void setCmds(CommandNode cmds)
    {
        m_cmds = cmds;
    }


    /***************************************************************************
    * Determine if this block definition is a func body.
    *
    * @since	1.2, 2007-03-21
    */
    boolean isFunc()
    {
        // Examine the name of the block
        return (m_type == CMD_FUNC);
    }


    /***************************************************************************
    * Add a local func definition to this block definition.
    *
    * @param	name
    * Func name.
    *
    * @param	cmd
    * Command ({@link #CMD_FUNC CMD_FUNC}) containing the func definition.
    *
    * @return
    * True if the func was added successfully, or false if it is already defined
    * within this block definition.
    *
    * @since	1.1, 2007-03-16
    */
    boolean addFuncDef(String name, CommandNode cmd)
    {
        // Add a func that is local to this block definition
        if (m_funcs == null)
            m_funcs = new HashMap<String, CommandNode>();

        if (m_funcs.get(name) != null)
            return false;

        m_funcs.put(name, cmd);
        return true;
    }


    /***************************************************************************
    * Retrieve a func definition within this block's scope.
    *
    * @param	name
    * Func name.
    *
    * @return
    * The command node ({@link #CMD_FUNC CMD_FUNC}) containing the func
    * definition, or null if no such func exists within the scope of this block
    * definition.
    *
    * @since	1.1, 2007-03-16
    */
    CommandNode findFuncDef(String name)
    {
        return findADef(name, NAMETYPE_FUNC);
    }


    /***************************************************************************
    * Find the block containing a func definition.
    *
    * @param	name
    * Var name.
    *
    * @return
    * The block definition containing the func definition ('func' command), or
    * null if the func is not defined within the scope of this block or any of
    * its outer blocks.
    *
    * @since	1.6, 2007-04-10
    */
    BlockDef findFuncBlock(String name)
    {
        return findABlock(name, NAMETYPE_FUNC);
    }


    /***************************************************************************
    * Add a local var definition to this block definition.
    *
    * @param	name
    * Var name.
    *
    * @param	cmd
    * Command ({@link #CMD_VAR CMD_VAR}) containing the var definition.
    *
    * @return
    * True if the var was added successfully, or false if it is already defined
    * within this block definition.
    *
    * @since	1.1, 2007-03-16
    */
    boolean addVarDef(String name, CommandNode cmd)
    {
        // Add a var that is local to this block definition
        if (m_vars == null)
            m_vars = new HashMap<String, CommandNode>();

        if (m_vars.get(name) != null)
            return false;

        m_vars.put(name, cmd);
        return true;
    }


    /***************************************************************************
    * Retrieve a var definition within this block's scope.
    *
    * @param	name
    * Var name.
    *
    * @return
    * The command node ({@link #CMD_VAR CMD_VAR}) containing the var definition,
    * or null if no such var exists in the scope of this block definition.
    *
    * @since	1.1, 2007-03-16
    */
    CommandNode findVarDef(String name)
    {
        return findADef(name, NAMETYPE_VAR);
    }


    /***************************************************************************
    * Find the block containing a var definition.
    *
    * @param	name
    * Var name.
    *
    * @return
    * The block definition containing the var definition ('var' command), or
    * null if the var is not defined within the scope of this block or any of
    * its outer blocks.
    *
    * @since	1.4, 2007-04-06
    */
    BlockDef findVarBlock(String name)
    {
        return findABlock(name, NAMETYPE_VAR);
    }


    /***************************************************************************
    * Add a local label definition to this block definition.
    *
    * @param	name
    * Label name.
    *
    * @param	cmd
    * Command ({@link #CMD_LABEL CMD_LABEL}) containing the statement label
    * definition.
    *
    * @return
    * True if the label was added successfully, or false if it is already
    * defined within this block definition.
    *
    * @since	1.1, 2007-03-16
    */
    boolean addLabelDef(String name, CommandNode cmd)
    {
        // Add a label that is local to this block definition
        if (m_labels == null)
            m_labels = new HashMap<String, CommandNode>();

        if (m_labels.get(name) != null)
            return false;

        m_labels.put(name, cmd);
        return true;
    }


    /***************************************************************************
    * Retrieve a local label definition in this block definition.
    *
    * @param	name
    * Label name.
    *
    * @return
    * The command node ({@link #CMD_LABEL CMD_LABEL}) containing the statement
    * label, or null if no such label exists in this block definition.
    *
    * @since	1.1, 2007-03-16
    */
    CommandNode findLabelDef(String name)
    {
        return findADef(name, NAMETYPE_LABEL);
    }


    /***************************************************************************
    * Find the block containing a label definition.
    *
    * @param	name
    * Label name.
    *
    * @return
    * The block definition containing the label definition, or null if the label
    * is not defined within the scope of this block or any of its outer blocks.
    * Blocks outside func bodies are not searched.
    *
    * @since	1.5, 2007-04-09
    */
    BlockDef findLabelBlock(String name)
    {
        return findABlock(name, NAMETYPE_LABEL);
    }


    /***************************************************************************
    * Retrieve a var/label/func definition within this block's scope.
    *
    * @param	name
    * Var, label, or func name.
    *
    * @param	type
    * One of the {@link #NAMETYPE_VAR NAMETYPE_<i>XXX</i>} constants, specifying
    * what kind of name <i>name</i> is.
    *
    * @return
    * The command node containing the definition of the name, or null if it does
    * not exist in the scope of this block.  Labels are not searched for outside
    * func bodies.
    *
    * @since	1.6, 2007-04-10
    */
    private CommandNode findADef(String name, int type)
    {
        BlockDef	scope;

        // Search for the definition within this block's scope
        for (scope = this;  scope != null;  scope = scope.m_outer)
        {
            HashMap<String, CommandNode>	list =	null;

            // Search the next block for the definition
            switch (type)
            {
            case NAMETYPE_VAR:		list = scope.m_vars;  break;
            case NAMETYPE_LABEL:	list = scope.m_labels;  break;
            case NAMETYPE_FUNC:		list = scope.m_funcs;  break;
            }

            if (list != null)
            {
                CommandNode	def;

                def = list.get(name);
                if (def != null)
                    return def;
            }

            // Expand the search to the next outer block,
            //  but do not search for labels outside a func block
            if (type == NAMETYPE_LABEL  &&  scope.isFunc())
                break;
        }

        // The definition was not found
        return null;
    }


    /***************************************************************************
    * Find the block containing a var/label/func definition.
    *
    * @param	name
    * Var, label, or func name.
    *
    * @param	type
    * One of the {@link #NAMETYPE_VAR NAMETYPE_<i>XXX</i>} constants, specifying
    * what kind of name <i>name</i> is.
    *
    * @return
    * The block definition containing the definition of the name, or null if it
    * is not defined within the scope of this block or any of its outer blocks.
    * Labels are not searched for outside func bodies.
    *
    * @since	1.6, 2007-04-10
    */
    private BlockDef findABlock(String name, int type)
    {
        BlockDef	scope;

        // Search for the definition within this block's scope
        for (scope = this;  scope != null;  scope = scope.m_outer)
        {
            HashMap<String, CommandNode>	list =	null;

            // Search the next block for the definition
            switch (type)
            {
            case NAMETYPE_VAR:		list = scope.m_vars;  break;
            case NAMETYPE_LABEL:	list = scope.m_labels;  break;
            case NAMETYPE_FUNC:		list = scope.m_funcs;  break;
            }

            // Search the next block for the definition
            if (list != null  &&  list.get(name) != null)
                return scope;

            // Expand the search to the next outer block,
            //  but do not search for labels outside a func block
            if (type == NAMETYPE_LABEL  &&  scope.isFunc())
                break;
        }

        // The definition was not found
        return null;
    }


    /***************************************************************************
    * Release objects that are no longer needed by this block definition after a
    * successful parse.
    *
    * @since	1.8, 2007-08-05
    */
    void scrub()
    {
        m_funcs =  null;
        m_vars =   null;
        m_labels = null;
    }


    /***************************************************************************
    * Pretty-print this block definition and its subordinate blocks.
    *
    * @since	1.9, 2007-08-07
    */
    void printTree(PrintWriter out)
    {
        if (out != null)
            printTree(out, "");
    }


    /***************************************************************************
    * Pretty-print this block definition and its subordinate blocks.
    *
    * @since	1.9, 2007-08-07
    */
    private void printTree(PrintWriter out, String indent)
    {
        CommandNode	cmd;

        // Print this block
        print(out, indent);

        // Print out this block's local definitions
        for (cmd = m_cmds;  cmd != null;  cmd = cmd.m_next)
        {
            String	type =	null;
            String	name =	null;

            if (cmd.m_cmd == CMD_LABEL)
            {
                type = "label";
                name = (String) cmd.m_args[0];
            }
            else if (cmd.m_cmd == CMD_VAR)
            {
                type = "var  ";
                name = (String) cmd.m_args[0];
            }
            else if (cmd.m_cmd == CMD_FUNC)
            {
                type = "func ";
                name = (String) cmd.m_args[0];
            }

            if (type != null)
            {
                out.print(indent);
                out.println("    " + type + " " + name + " @" + cmd.m_lineNo);
            }
        }

        // Print this block's children (nested) blocks
        for (cmd = m_cmds;  cmd != null;  cmd = cmd.m_next)
        {
            if (cmd.m_cmd == CMD_GOTO)
                continue;
            if (cmd.m_args == null)
                continue;

            for (int i = 0;  i < cmd.m_args.length;  i++)
            {
                if (cmd.m_args[i] instanceof BlockDef)
                {
                    BlockDef	sub;

                    sub = (BlockDef) cmd.m_args[i];
                    if (sub.m_lineNo > this.m_lineNo)
                        sub.printTree(out, indent + "  ");
                }
            }
        }
    }


    /***************************************************************************
    * Pretty-print this block definition.
    *
    * @since	1.9, 2007-08-07
    */
    private void print(PrintWriter out, String indent)
    {
        // Display the contents of this block definition
        out.print(indent);
        out.print(m_lineNo + ": {" + m_depth + "} \"" + m_name + "\" /"
            + m_type);
        if (m_parent != null)
            out.print(" : " + m_parent.m_cmd + " @" + m_parent.m_lineNo);
        out.println();
    }
}

// End BlockDef.java