/*
* TclBoolean.java
*
* Copyright (c) 1997 Sun Microsystems, Inc.
*
* 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: TclBoolean.java,v 1.2 2000/10/29 06:00:42 mdejong Exp $
*
*/
using System;
namespace tcl.lang
{

  /// <summary> This class implements the boolean object type in Tcl.</summary>

  public class TclBoolean : InternalRep
  {
    /// <summary> Internal representation of a boolean value.</summary>
    private bool value;

    /// <summary> Construct a TclBoolean representation with the given boolean value.
    /// 
    /// </summary>
    /// <param name="b">initial boolean value.
    /// </param>
    private TclBoolean( bool b )
    {
      value = b;
    }

    /// <summary> Construct a TclBoolean representation with the initial value taken
    /// from the given string.
    /// 
    /// </summary>
    /// <param name="interp">current interpreter.
    /// </param>
    /// <exception cref=""> TclException if the string is not a well-formed Tcl boolean
    /// value.
    /// </exception>
    private TclBoolean( Interp interp, string str )
    {
      value = Util.getBoolean( interp, str );
    }

    /// <summary> Returns a dupilcate of the current object.
    /// 
    /// </summary>
    /// <param name="tobj">the TclObject that contains this ObjType.
    /// </param>
    public InternalRep duplicate()
    {
      return new TclBoolean( value );
    }

    /// <summary> Implement this no-op for the InternalRep interface.</summary>

    public void dispose()
    {
    }

    /// <summary> Called to query the string representation of the Tcl object. This
    /// method is called only by TclObject.toString() when
    /// TclObject.stringRep is null.
    /// 
    /// </summary>
    /// <returns> the string representation of the Tcl object.
    /// </returns>
    public override string ToString()
    {
      if ( value )
      {
        return "1";
      }
      else
      {
        return "0";
      }
    }

    /// <summary> Creates a new instance of a TclObject with a TclBoolean internal
    /// representation.
    /// 
    /// </summary>
    /// <param name="b">initial value of the boolean object.
    /// </param>
    /// <returns> the TclObject with the given boolean value.
    /// </returns>

    public static TclObject newInstance( bool b )
    {
      return new TclObject( new TclBoolean( b ) );
    }

    /// <summary> Called to convert the other object's internal rep to boolean.
    /// 
    /// </summary>
    /// <param name="interp">current interpreter.
    /// </param>
    /// <param name="tobj">the TclObject to convert to use the
    /// representation provided by this class.
    /// </param>
    private static void setBooleanFromAny( Interp interp, TclObject tobj )
    {
      InternalRep rep = tobj.InternalRep;

      if ( rep is TclBoolean )
      {
        /*
        * Do nothing.
        */
      }
      else if ( rep is TclInteger )
      {
        int i = TclInteger.get( interp, tobj );
        tobj.InternalRep = new TclBoolean( i != 0 );
      }
      else
      {
        /*
        * (ToDo) other short-cuts
        */
        tobj.InternalRep = new TclBoolean( interp, tobj.ToString() );
      }
    }

    /// <summary> Returns the value of the object as an boolean.
    /// 
    /// </summary>
    /// <param name="interp">current interpreter.
    /// </param>
    /// <param name="tobj">the TclObject to use as an boolean.
    /// </param>
    /// <returns> the boolean value of the object.
    /// </returns>
    /// <exception cref=""> TclException if the object cannot be converted into a
    /// boolean.
    /// </exception>
    public static bool get( Interp interp, TclObject tobj )
    {
      setBooleanFromAny( interp, tobj );
      TclBoolean tbool = (TclBoolean)( tobj.InternalRep );
      return tbool.value;
    }
  }
}