/*
* VariableCmd.java
*
* Copyright (c) 1987-1994 The Regents of the University of California.
* Copyright (c) 1994-1997 Sun Microsystems, Inc.
* Copyright (c) 1998-1999 by Scriptics Corporation.
* Copyright (c) 1999      by Moses DeJong.
*
* See the file "license.terms" for information on usage and
* redistribution of this file, and for a DISCLAIMER OF ALL
* WARRANTIES.
*
* Included in SQLite3 port to C# for use in testharness only;  2008 Noah B Hart
*
* RCS @(#) $Id: VariableCmd.java,v 1.3 1999/06/30 00:13:39 mo Exp $
*/
using System;
namespace tcl.lang
{

  /// <summary> This class implements the built-in "variable" command in Tcl.</summary>

  class VariableCmd : Command
  {
    public TCL.CompletionCode cmdProc( Interp interp, TclObject[] objv )
    {


      string varName;
      int tail, cp;
      Var var, array;
      TclObject varValue;
      int i;

      for ( i = 1; i < objv.Length; i = i + 2 )
      {
        // Look up each variable in the current namespace context, creating
        // it if necessary.


        varName = objv[i].ToString();
        Var[] result = Var.lookupVar( interp, varName, null, ( TCL.VarFlag.NAMESPACE_ONLY | TCL.VarFlag.LEAVE_ERR_MSG ), "define", true, false );
        if ( result == null )
        {
          // FIXME:
          throw new TclException( interp, "" );
        }

        var = result[0];
        array = result[1];

        // Mark the variable as a namespace variable and increment its 
        // reference count so that it will persist until its namespace is
        // destroyed or until the variable is unset.

        if ( ( var.flags & VarFlags.NAMESPACE_VAR ) == 0 )
        {
          var.flags |= VarFlags.NAMESPACE_VAR;
          var.refCount++;
        }

        // If a value was specified, set the variable to that value.
        // Otherwise, if the variable is new, leave it undefined.
        // (If the variable already exists and no value was specified,
        // leave its value unchanged; just create the local link if
        // we're in a Tcl procedure).

        if ( i + 1 < objv.Length )
        {
          // a value was specified
          varValue = Var.setVar( interp, objv[i], null, objv[i + 1], ( TCL.VarFlag.NAMESPACE_ONLY | TCL.VarFlag.LEAVE_ERR_MSG ) );

          if ( varValue == null )
          {
            // FIXME:
            throw new TclException( interp, "" );
          }
        }



        // If we are executing inside a Tcl procedure, create a local
        // variable linked to the new namespace variable "varName".

        if ( ( interp.varFrame != null ) && interp.varFrame.isProcCallFrame )
        {

          // varName might have a scope qualifier, but the name for the
          // local "link" variable must be the simple name at the tail.
          //
          // Locate tail in one pass: drop any prefix after two *or more*
          // consecutive ":" characters).

          int len = varName.Length;

          for ( tail = cp = 0; cp < len; )
          {
            if ( varName[cp++] == ':' )
            {
              while ( ( cp < len ) && ( varName[cp++] == ':' ) )
              {
                tail = cp;
              }
            }
          }

          // Create a local link "tail" to the variable "varName" in the
          // current namespace.

          Var.makeUpvar( interp, null, varName, null, TCL.VarFlag.NAMESPACE_ONLY, varName.Substring( tail ), 0 );
        }
      }
      return TCL.CompletionCode.RETURN;
    }
  }
}