##############################################################################
#
# Copyright (c) 2004, 2005 Zope Corporation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""Marker interfaces adapter.

Allows for arbitrary application of marker interfaces to objects.

$Id: marker.py 67820 2006-05-02 09:21:45Z philikon $
"""
from sets import Set

from zope.interface import implements, implementedBy, providedBy
from zope.interface import directlyProvides, directlyProvidedBy
from zope.interface.interfaces import IInterface
from zope.component.interface import getInterface, interfaceToName
from zope.component.interface import searchInterface

from interfaces import IMarkerInterfaces

def interfaceStringCheck(f):
    def wrapper(ob, interface):
        if isinstance(interface, str):
            interface = getInterface(ob, interface)
        return f(ob, interface)
    return wrapper

def mark(ob, interface):
    directlyProvides(ob, directlyProvidedBy(ob), interface)

def erase(ob, interface):
    directlyProvides(ob, directlyProvidedBy(ob)-interface)

mark = interfaceStringCheck(mark)
erase = interfaceStringCheck(erase)


class MarkerInterfacesAdapter(object):

    implements(IMarkerInterfaces)

    mark = staticmethod(mark)
    erase = staticmethod(erase)

    def __init__(self, context):
        self.context = context

    def dottedToInterfaces(self, seq):
        return [getInterface(self.context, dotted) for dotted in seq]

    def getDirectlyProvided(self):
        return directlyProvidedBy(self.context)

    def getDirectlyProvidedNames(self):
        return self._getInterfaceNames(self.getDirectlyProvided())

    def getAvailableInterfaces(self):
        results = []
        todo = list(providedBy(self.context))
        done = []
        while todo:
            interface = todo.pop()
            done.append(interface)
            for base in interface.__bases__:
                if base not in todo and base not in done:
                    todo.append(base)
            markers = self._getDirectMarkersOf(interface)
            for interface in markers:
                if (interface not in results
                    and not interface.providedBy(self.context)):
                    results.append(interface)
            todo += markers
        return tuple(results)

    def getAvailableInterfaceNames(self):
        names = self._getInterfaceNames(self.getAvailableInterfaces())
        names.sort()
        return names

    def getInterfaces(self):
        return tuple(implementedBy(self.context.__class__))

    def getInterfaceNames(self):
        return self._getInterfaceNames(self.getInterfaces())

    def getProvided(self):
        return providedBy(self.context)

    def getProvidedNames(self):
        return self._getInterfaceNames(self.getProvided())

    def update(self, add=(), remove=()):
        """Currently update adds and then removes, rendering duplicate null.
        """
        marker_ifaces = self.getAvailableInterfaces()
        if len(add):
            [mark(self.context, interface)
             for interface in Set(marker_ifaces) & Set(add)]

        direct_ifaces = self.getDirectlyProvided()
        if len(remove):
            [erase(self.context, interface)
             for interface in Set(direct_ifaces) & Set(remove)]

    def _getInterfaceNames(self, interfaces):
        return [interfaceToName(self, iface) for iface in interfaces]

    def _getDirectMarkersOf(self, base):
        """Get empty interfaces directly inheriting from the given one.
        """
        results = []
        interfaces = searchInterface(None, base=base)
        for interface in interfaces:
            # There are things registered with the interface service
            # that are not interfaces. Yay!
            if not IInterface.providedBy(interface):
                continue
            if base in interface.__bases__ and not interface.names():
                results.append(interface)
        results.sort()
        return tuple(results)
