# scopes.interfaces

from zope.interface import Interface, Attribute


class IViewable(Interface):

    prefix = Attribute('Prefix string for identifying the type (class) of an object')


class ITraversable(IViewable):

    def get(key, default=None):
        """Return the item addressed by `key`; return `default` if not found."""


class IContainer(ITraversable):

    def values():
        """Return a sequence of child objects."""

    def __getitem__(key):
        """Return the item addressed by `key`; raise KeyError if not found."""

    def __setitem__(key, value):
        """Store the `value` under the `key`. 

        May modify `value` so that the attributes referencing this object
        and the value object (e.g. `parent` and `name`) are stored correctly."""


class IReference(Interface):

    def getTarget():
        """Return item referenced by this object."""

    def setTarget(target):
        """Store reference to target item."""


class IView(Interface):

    def __call__():
        """Render the view data as HTML or JSON."""