#------------------------------------------------------------------------------
#
#  Copyright (c) 2005, Enthought, Inc.
#  All rights reserved.
#
#  This software is provided without warranty under the terms of the BSD
#  license included in enthought/LICENSE.txt and may be redistributed only
#  under the conditions described in the aforementioned license.  The license
#  is also available online at http://www.enthought.com/licenses/BSD.txt
#
#  Thanks for using Enthought open source!
#
#  Author: David C. Morrill
#  Date:   10/13/2004
#
#------------------------------------------------------------------------------

""" Defines the UIInfo class used to represent the object and editor content of
    an active Traits-based user interface.
"""

#-------------------------------------------------------------------------------
#  Imports:
#-------------------------------------------------------------------------------

from __future__ import absolute_import

from traits.api import HasPrivateTraits, Instance, Constant, Bool

#-------------------------------------------------------------------------------
#  'UIInfo' class:
#-------------------------------------------------------------------------------

class UIInfo ( HasPrivateTraits ):
    """ Represents the object and editor content of an active Traits-based
    user interface
    """

    #---------------------------------------------------------------------------
    #  Trait definitions:
    #---------------------------------------------------------------------------

    # Bound to a UI object at UIInfo construction time
    ui = Instance( 'traitsui.ui.UI', allow_none = True )

    # Indicates whether the UI has finished initialization
    initialized = Bool( False )

    #---------------------------------------------------------------------------
    #  Bind's all of the associated context objects as traits of the object:
    #---------------------------------------------------------------------------

    def bind_context ( self ):
        """ Binds all of the associated context objects as traits of the
            object.
        """
        for name, value in self.ui.context.items():
            self.bind( name, value )

    #---------------------------------------------------------------------------
    #  Binds a name to a value if it is not already bound:
    #---------------------------------------------------------------------------

    def bind ( self, name, value, id = None ):
        """ Binds a name to a value if it is not already bound.
        """
        if id is None:
            id = name

        if not hasattr( self, name ):
            self.add_trait( name, Constant( value ) )
            if id != '':
                self.ui._names.append( id )

