##############################################################################
#
# Copyright (c) 2004 Zope Foundation and Contributors.
#
# 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.
#
##############################################################################
""" GenericSetup product utilities
"""

import os
import six
import sys
from cgi import escape
from inspect import getdoc
from logging import getLogger
from xml.dom.minidom import _nssplit
from xml.dom.minidom import Document
from xml.dom.minidom import Element
from xml.dom.minidom import Node
from xml.dom.minidom import parseString
from xml.parsers.expat import ExpatError

from AccessControl.class_init import InitializeClass
from AccessControl.SecurityInfo import ClassSecurityInfo
from Acquisition import Implicit
from App.Common import package_home
from OFS.interfaces import IOrderedContainer
from Products.Five.utilities.interfaces import IMarkerInterfaces
from zope.component import queryMultiAdapter
from zope.interface import directlyProvides
from zope.interface import implementer
from zope.interface import implementer_only
from ZPublisher.Converters import type_converters
from ZPublisher.HTTPRequest import default_encoding

from Products.GenericSetup.exceptions import BadRequest
from Products.GenericSetup.interfaces import IBody
from Products.GenericSetup.interfaces import INode
from Products.GenericSetup.interfaces import ISetupTool
from Products.GenericSetup.permissions import ManagePortal


_pkgdir = package_home(globals())
_wwwdir = os.path.join(_pkgdir, 'www')
_xmldir = os.path.join(_pkgdir, 'xml')

# Please note that these values may change. Always import
# the values from here instead of using the values directly.
CONVERTER, DEFAULT, KEY = 1, 2, 3
I18NURI = 'http://xml.zope.org/namespaces/i18n'


def _getDottedName(named):

    if isinstance(named, six.string_types):
        return str(named)

    try:
        dotted = '%s.%s' % (named.__module__, named.__name__)
    except AttributeError:
        raise ValueError('Cannot compute dotted name: %s' % named)

    # remove leading underscore names if possible

    # Step 1: check if there is a short version
    short_dotted = '.'.join([n for n in dotted.split('.')
                             if not n.startswith('_')])
    if short_dotted == dotted:
        return dotted

    # Step 2: check if short version can be resolved
    try:
        short_resolved = _resolveDottedName(short_dotted)
    except (ValueError, ImportError):
        return dotted

    # Step 3: check if long version resolves to the same object
    try:
        resolved = _resolveDottedName(dotted)
    except (ValueError, ImportError):
        raise ValueError('Cannot compute dotted name: %s' % named)
    if short_resolved is not resolved:
        return dotted

    return short_dotted


def _resolveDottedName(dotted):
    __traceback_info__ = dotted

    parts = dotted.split('.')

    if not parts:
        raise ValueError("incomplete dotted name: %s" % dotted)

    parts_copy = parts[:]

    while parts_copy:
        try:
            module = __import__('.'.join(parts_copy))
            break

        except ImportError:
            # Reraise if the import error was caused inside the imported file
            if sys.exc_info()[2].tb_next is not None:
                raise

            del parts_copy[-1]

            if not parts_copy:
                return None

    parts = parts[1:]  # Funky semantics of __import__'s return value

    obj = module

    for part in parts:
        try:
            obj = getattr(obj, part)
        except AttributeError:
            return None

    return obj


def _extractDocstring(func, default_title, default_description):
    try:
        doc = getdoc(func)
        lines = doc.split('\n')

    except AttributeError:

        title = default_title
        description = default_description

    else:
        title = lines[0]

        if len(lines) > 1 and lines[1].strip() == '':
            del lines[1]

        description = '\n'.join(lines[1:])

    return title, description


##############################################################################
# WARNING: PLEASE DON'T USE THE CONFIGURATOR PATTERN. THE RELATED BASE CLASSES
# WILL BECOME DEPRECATED AS SOON AS GENERICSETUP ITSELF NO LONGER USES THEM.

class ImportConfiguratorBase(Implicit):
    # old code, will become deprecated
    """ Synthesize data from XML description.
    """
    security = ClassSecurityInfo()
    security.setDefaultAccess('allow')

    def __init__(self, site, encoding='utf-8'):

        self._site = site
        self._encoding = encoding if six.PY2 else None

    @security.protected(ManagePortal)
    def parseXML(self, xml):
        """ Pseudo API.
        """
        reader = getattr(xml, 'read', None)

        if reader is not None:
            xml = reader()

        if six.PY3:
            if isinstance(xml, bytes):
                xml = xml.decode('utf-8')

        dom = parseString(xml)
        root = dom.documentElement

        return self._extractNode(root)

    def _extractNode(self, node):
        """ Please see docs/configurator.txt for information about the
        import mapping syntax.
        """
        nodes_map = self._getImportMapping()
        if node.nodeName not in nodes_map:
            nodes_map = self._getSharedImportMapping()
            if node.nodeName not in nodes_map:
                raise ValueError('Unknown node: %s' % node.nodeName)
        node_map = nodes_map[node.nodeName]
        info = {}

        for name, val in node.attributes.items():
            key = node_map[name].get(KEY, str(name))
            val = self._encoding and val.encode(self._encoding) or val
            info[key] = val

        for child in node.childNodes:
            name = child.nodeName

            if name == '#comment':
                continue

            if not name == '#text':
                key = node_map[name].get(KEY, str(name))
                info[key] = info.setdefault(key, ()) + (
                                                    self._extractNode(child),)

            elif '#text' in node_map:
                key = node_map['#text'].get(KEY, 'value')
                val = child.nodeValue.lstrip()
                val = self._encoding and val.encode(self._encoding) or val
                info[key] = info.setdefault(key, '') + val

        for k, v in node_map.items():
            key = v.get(KEY, k)

            if DEFAULT in v and key not in info:
                if isinstance(v[DEFAULT], six.string_types):
                    info[key] = v[DEFAULT] % info
                else:
                    info[key] = v[DEFAULT]

            elif CONVERTER in v and key in info:
                info[key] = v[CONVERTER](info[key])

            if key is None:
                info = info[key]

        return info

    def _getSharedImportMapping(self):

        return {
          'object': {'i18n:domain': {},
                     'name': {KEY: 'id'},
                     'meta_type': {},
                     'insert-before': {},
                     'insert-after': {},
                     'property': {KEY: 'properties', DEFAULT: ()},
                     'object': {KEY: 'objects', DEFAULT: ()},
                     'xmlns:i18n': {}},
          'property': {'name': {KEY: 'id'},
                       '#text': {KEY: 'value', DEFAULT: ''},
                       'element': {KEY: 'elements', DEFAULT: ()},
                       'type': {},
                       'select_variable': {},
                       'i18n:translate': {}},
          'element': {'value': {KEY: None}},
          'description': {'#text': {KEY: None, DEFAULT: ''}}}

    def _convertToBoolean(self, val):

        return val.lower() in ('true', 'yes', '1')

    def _convertToUnique(self, val):

        assert len(val) == 1
        return val[0]


InitializeClass(ImportConfiguratorBase)


class ExportConfiguratorBase(Implicit):
    # old code, will become deprecated
    """ Synthesize XML description.
    """
    security = ClassSecurityInfo()
    security.setDefaultAccess('allow')

    def __init__(self, site, encoding='utf-8'):

        self._site = site
        self._encoding = encoding
        self._template = self._getExportTemplate()

    @security.protected(ManagePortal)
    def generateXML(self, **kw):
        """ Pseudo API.
        """
        if six.PY2 and self._encoding:
            return self._template(**kw).encode(self._encoding)
        else:
            return self._template(**kw)


InitializeClass(ExportConfiguratorBase)

#
##############################################################################


class _LineWrapper:

    def __init__(self, writer, indent, addindent, newl, max):
        self._writer = writer
        self._indent = indent
        self._addindent = addindent
        self._newl = newl
        self._max = max
        self._length = 0
        self._queue = self._indent

    def queue(self, text):
        self._queue += text

    def write(self, text='', enforce=False):
        self._queue += text

        if 0 < self._length > self._max - len(self._queue):
            self._writer.write(self._newl)
            self._length = 0
            self._queue = '%s%s %s' % (self._indent, self._addindent,
                                       self._queue)

        if self._queue != self._indent:
            self._writer.write(self._queue)
            self._length += len(self._queue)
            self._queue = ''

        if 0 < self._length and enforce:
            self._writer.write(self._newl)
            self._length = 0
            self._queue = self._indent


class _Element(Element):

    """minidom element with 'pretty' XML output.
    """

    def writexml(self, writer, indent="", addindent="", newl=""):
        # indent = current indentation
        # addindent = indentation to add to higher levels
        # newl = newline string
        wrapper = _LineWrapper(writer, indent, addindent, newl, 78)
        wrapper.write('<%s' % self.tagName)

        # move 'name', 'meta_type' and 'title' to the top, sort the rest
        attrs = self._get_attributes()
        a_names = sorted(attrs.keys())
        if 'title' in a_names:
            a_names.remove('title')
            a_names.insert(0, 'title')
        if 'meta_type' in a_names:
            a_names.remove('meta_type')
            a_names.insert(0, 'meta_type')
        if 'name' in a_names:
            a_names.remove('name')
            a_names.insert(0, 'name')

        for a_name in a_names:
            wrapper.write()
            a_value = attrs[a_name].value
            if a_value is None:
                a_value = ""
            else:
                a_value = escape(a_value, quote=True)

            wrapper.queue(' %s="%s"' % (a_name, a_value))

        if self.childNodes:
            wrapper.queue('>')
            for node in self.childNodes:
                if node.nodeType == Node.TEXT_NODE:
                    data = escape(node.data)
                    textlines = data.splitlines()
                    if textlines:
                        wrapper.queue(textlines.pop(0))
                    if textlines:
                        for textline in textlines:
                            wrapper.write('', True)
                            wrapper.queue('%s%s' % (addindent, textline))
                else:
                    wrapper.write('', True)
                    node.writexml(writer, indent + addindent, addindent, newl)
            wrapper.write('</%s>' % self.tagName, True)
        else:
            wrapper.write('/>', True)


class PrettyDocument(Document):

    """minidom document with 'pretty' XML output.
    """

    def createElement(self, tagName):
        e = _Element(tagName)
        e.ownerDocument = self
        return e

    def createElementNS(self, namespaceURI, qualifiedName):
        prefix, _localName = _nssplit(qualifiedName)
        e = _Element(qualifiedName, namespaceURI, prefix)
        e.ownerDocument = self
        return e

    def writexml(self, writer, indent="", addindent="", newl="",
                 encoding='utf-8'):
        if encoding is None:
            writer.write('<?xml version="1.0"?>\n')
        else:
            writer.write('<?xml version="1.0" encoding="%s"?>\n' % encoding)
        for node in self.childNodes:
            node.writexml(writer, indent, addindent, newl)

    def toprettyxml(self, indent='\t', newl='\n', encoding='utf-8'):
        # `super` does not work here in python 2.7, yuck!
        return Document.toprettyxml(self, indent, newl, encoding)


@implementer(INode)
class NodeAdapterBase(object):

    """Node im- and exporter base.
    """

    _encoding = 'utf-8'
    _LOGGER_ID = ''

    def __init__(self, context, environ):
        self.context = context
        self.environ = environ
        self._logger = environ.getLogger(self._LOGGER_ID)
        self._doc = PrettyDocument()

    def _getObjectNode(self, name, i18n=True):
        node = self._doc.createElement(name)
        node.setAttribute('name', self.context.getId())
        node.setAttribute('meta_type', self.context.meta_type)
        i18n_domain = getattr(self.context, 'i18n_domain', None)
        if i18n and i18n_domain:
            node.setAttributeNS(I18NURI, 'i18n:domain', i18n_domain)
            self._i18n_props = ('title', 'description')
        return node

    def _getNodeText(self, node):
        text = ''
        for child in node.childNodes:
            if child.nodeName != '#text':
                continue
            lines = [line.lstrip() for line in child.nodeValue.splitlines()]
            text += '\n'.join(lines)
        return text

    def _convertToBoolean(self, val):
        return val.lower() in ('true', 'yes', '1')


@implementer_only(IBody)
class BodyAdapterBase(NodeAdapterBase):

    """Body im- and exporter base.
    """

    def _exportSimpleNode(self):
        """Export the object as a DOM node.
        """
        if ISetupTool.providedBy(self.context):
            return None
        return self._getObjectNode('object', False)

    def _importSimpleNode(self, node):
        """Import the object from the DOM node.
        """

    node = property(_exportSimpleNode, _importSimpleNode)

    def _exportBody(self):
        """Export the object as a file body.
        """
        return b''

    def _importBody(self, body):
        """Import the object from the file body.
        """

    body = property(_exportBody, _importBody)

    mime_type = 'text/plain'

    name = ''

    suffix = ''


@implementer_only(IBody)
class XMLAdapterBase(BodyAdapterBase):

    """XML im- and exporter base.
    """

    def _exportBody(self):
        """Export the object as a file body.
        """
        self._doc.appendChild(self._exportNode())
        xml = self._doc.toprettyxml(' ', encoding=self._encoding)
        self._doc.unlink()
        return xml

    def _importBody(self, body):
        """Import the object from the file body.
        """
        try:
            dom = parseString(body)
        except ExpatError as e:
            filename = (self.filename or
                        '/'.join(self.context.getPhysicalPath()))
            raise ExpatError('%s: %s' % (filename, e))

        # Replace the encoding with the one from the XML
        self._encoding = dom.encoding or self._encoding
        self._importNode(dom.documentElement)

    body = property(_exportBody, _importBody)

    mime_type = 'text/xml'

    name = ''

    suffix = '.xml'

    filename = ''  # for error reporting during import


class ObjectManagerHelpers(object):

    """ObjectManager in- and export helpers.
    """

    def _extractObjects(self):
        fragment = self._doc.createDocumentFragment()
        objects = self.context.objectValues()
        if not IOrderedContainer.providedBy(self.context):
            objects = list(objects)
            objects.sort(key=lambda x: x.getId())
        for obj in objects:
            exporter = queryMultiAdapter((obj, self.environ), INode)
            if exporter:
                node = exporter.node
                if node is not None:
                    fragment.appendChild(exporter.node)
        return fragment

    def _purgeObjects(self):
        for obj_id, obj in self.context.objectItems():
            if ISetupTool.providedBy(obj):
                continue
            self.context._delObject(obj_id)

    def _initObjects(self, node):
        import Products
        for child in node.childNodes:
            if child.nodeName != 'object':
                continue
            if child.hasAttribute('deprecated'):
                continue
            parent = self.context

            obj_id = str(child.getAttribute('name'))
            if self._convertToBoolean(child.getAttribute('remove') or 'False'):
                if obj_id in parent.objectIds():
                    parent._delObject(obj_id)
                continue

            if obj_id not in parent.objectIds():
                meta_type = str(child.getAttribute('meta_type'))
                __traceback_info__ = obj_id, meta_type
                for mt_info in Products.meta_types:
                    if mt_info['name'] == meta_type:
                        parent._setObject(obj_id, mt_info['instance'](obj_id))
                        break
                else:
                    raise ValueError("unknown meta_type '%s'" % meta_type)

            if child.hasAttribute('insert-before'):
                insert_before = child.getAttribute('insert-before')
                if insert_before == '*':
                    parent.moveObjectsToTop(obj_id)
                else:
                    try:
                        position = parent.getObjectPosition(insert_before)
                        if parent.getObjectPosition(obj_id) < position:
                            position -= 1
                        parent.moveObjectToPosition(obj_id, position)
                    except ValueError:
                        pass
            elif child.hasAttribute('insert-after'):
                insert_after = child.getAttribute('insert-after')
                if insert_after == '*':
                    parent.moveObjectsToBottom(obj_id)
                else:
                    try:
                        position = parent.getObjectPosition(insert_after)
                        if parent.getObjectPosition(obj_id) < position:
                            position -= 1
                        parent.moveObjectToPosition(obj_id, position + 1)
                    except ValueError:
                        pass

            obj = getattr(self.context, obj_id)
            importer = queryMultiAdapter((obj, self.environ), INode)
            if importer:
                importer.node = child


class PropertyManagerHelpers(object):

    """PropertyManager im- and export helpers.

      o Derived classes can supply a '_PROPERTIES' scehma, which is then used
        to mock up a temporary propertysheet for the object.  The adapter's
        methods ('_extractProperties', '_purgeProperties', '_initProperties')
        then run against that propertysheet.
    """
    _PROPERTIES = ()

    _encoding = default_encoding

    def __init__(self, context, environ):
        from OFS.PropertyManager import PropertyManager
        if not isinstance(context, PropertyManager):
            context = self._fauxAdapt(context)

        super(PropertyManagerHelpers, self).__init__(context, environ)

    def _fauxAdapt(self, context):
        from OFS.PropertySheets import PropertySheet

        class Adapted(PropertySheet):
            def __init__(self, real, properties):
                self._real = real
                self._properties = properties

            def p_self(self):
                return self

            def v_self(self):
                return self._real

            def propdict(self):
                # PropertyManager method used by _initProperties
                return dict([(p['id'], p) for p in self._properties])

        return Adapted(context, self._PROPERTIES)

    def _extractProperties(self):
        fragment = self._doc.createDocumentFragment()

        for prop_map in self.context._propertyMap():
            prop_id = prop_map['id']
            if prop_id == 'i18n_domain':
                continue

            # Don't export read-only nodes
            if 'w' not in prop_map.get('mode', 'wd'):
                continue

            node = self._doc.createElement('property')
            node.setAttribute('name', prop_id)

            prop = self.context.getProperty(prop_id)
            if prop is None:
                continue
            if isinstance(prop, (tuple, list)):
                for value in prop:
                    if isinstance(value, six.binary_type):
                        value = value.decode(self._encoding)
                    child = self._doc.createElement('element')
                    child.setAttribute('value', value)
                    node.appendChild(child)
            else:
                if prop_map.get('type') == 'boolean':
                    prop = six.u(str(bool(prop)))
                elif prop_map.get('type') == 'date':
                    if prop.timezoneNaive():
                        prop = six.u(str(prop).rsplit(None, 1)[0])
                    else:
                        prop = six.u(str(prop))
                elif isinstance(prop, six.binary_type):
                    prop = prop.decode(self._encoding)
                elif isinstance(prop, (six.integer_types, float)):
                    prop = six.u(str(prop))
                elif not isinstance(prop, six.string_types):
                    prop = prop.decode(self._encoding)
                child = self._doc.createTextNode(prop)
                node.appendChild(child)

            if 'd' in prop_map.get('mode', 'wd') and not prop_id == 'title':
                prop_type = prop_map.get('type', 'string')
                node.setAttribute('type', six.u(prop_type))
                select_variable = prop_map.get('select_variable', None)
                if select_variable is not None:
                    node.setAttribute('select_variable', select_variable)

            if hasattr(self, '_i18n_props') and prop_id in self._i18n_props:
                node.setAttribute('i18n:translate', '')

            fragment.appendChild(node)

        return fragment

    def _purgeProperties(self):
        for prop_map in self.context._propertyMap():
            mode = prop_map.get('mode', 'wd')
            if 'w' not in mode:
                continue
            prop_id = prop_map['id']
            if 'd' in mode and not prop_id == 'title':
                self.context._delProperty(prop_id)
            else:
                prop_type = prop_map.get('type')
                if prop_type == 'multiple selection':
                    prop_value = ()
                elif prop_type in ('int', 'float'):
                    prop_value = 0
                elif prop_type == 'date':
                    prop_value = '1970/01/01 00:00:00 UTC'  # DateTime(0) UTC
                else:
                    prop_value = ''
                self.context._updateProperty(prop_id, prop_value)

    def _initProperties(self, node):
        obj = self.context
        if node.hasAttribute('i18n:domain'):
            i18n_domain = str(node.getAttribute('i18n:domain'))
            obj._updateProperty('i18n_domain', i18n_domain)
        for child in node.childNodes:
            if child.nodeName != 'property':
                continue
            remove = self._convertToBoolean(
                child.getAttribute('remove') or 'False')
            prop_id = str(child.getAttribute('name'))
            prop_map = obj.propdict().get(prop_id, None)

            if prop_map is None:
                if remove:
                    continue
                if child.hasAttribute('type'):
                    val = str(child.getAttribute('select_variable'))
                    prop_type = str(child.getAttribute('type'))
                    obj._setProperty(prop_id, val, prop_type)
                    prop_map = obj.propdict().get(prop_id, None)
                else:
                    raise ValueError("undefined property '%s'" % prop_id)

            if remove:
                if 'd' not in prop_map.get('mode', 'wd'):
                    raise BadRequest('%s cannot be deleted' % prop_id)
                obj._delProperty(prop_id)
                continue

            if 'w' not in prop_map.get('mode', 'wd'):
                raise BadRequest('%s cannot be changed' % prop_id)

            new_elements = []
            remove_elements = []
            for sub in child.childNodes:
                if sub.nodeName == 'element':
                    value = sub.getAttribute('value').encode(self._encoding)
                    if self._convertToBoolean(sub.getAttribute('remove')
                                              or 'False'):
                        remove_elements.append(value)
                        if value in new_elements:
                            new_elements.remove(value)
                    else:
                        new_elements.append(value)
                        if value in remove_elements:
                            remove_elements.remove(value)

            if prop_map.get('type') in ('lines', 'tokens',
                                        'multiple selection'):
                prop_value = tuple(new_elements) or ()
            elif prop_map.get('type') == 'boolean':
                prop_value = self._convertToBoolean(self._getNodeText(child))
            else:
                # if we pass a *string* to _updateProperty, all other values
                # are converted to the right type
                prop_value = self._getNodeText(child).encode(self._encoding)

            if not self._convertToBoolean(child.getAttribute('purge')
                                          or 'True'):
                # If the purge attribute is False, merge sequences
                prop = obj.getProperty(prop_id)
                if isinstance(prop, (tuple, list)):
                    prop_value = (tuple([p for p in prop
                                         if p not in prop_value and
                                         p not in remove_elements]) +
                                  tuple(prop_value))

            if isinstance(prop_value, (six.binary_type, str)):
                prop_type = obj.getPropertyType(prop_id) or 'string'
                if prop_type in type_converters:
                    # The type_converters use the ZPublisher default_encoding
                    # for decoding bytes!
                    if self._encoding != default_encoding:
                        u_prop_value = prop_value.decode(self._encoding)
                        prop_value = u_prop_value.encode(default_encoding)
                        prop_value = type_converters[prop_type](prop_value)
                        if six.PY2:
                            u_prop_value = prop_value.decode(default_encoding)
                            prop_value = u_prop_value.encode(self._encoding)
                    else:
                        prop_value = type_converters[prop_type](prop_value)
            obj._updateProperty(prop_id, prop_value)


class MarkerInterfaceHelpers(object):

    """Marker interface im- and export helpers.
    """

    def _extractMarkers(self):
        fragment = self._doc.createDocumentFragment()
        adapted = IMarkerInterfaces(self.context)

        for marker_id in adapted.getDirectlyProvidedNames():
            node = self._doc.createElement('marker')
            node.setAttribute('name', marker_id)
            fragment.appendChild(node)

        return fragment

    def _purgeMarkers(self):
        directlyProvides(self.context)

    def _initMarkers(self, node):
        markers = []
        adapted = IMarkerInterfaces(self.context)

        for child in node.childNodes:
            if child.nodeName != 'marker':
                continue
            markers.append(str(child.getAttribute('name')))

        adapted.update(adapted.dottedToInterfaces(markers))


def exportObjects(obj, parent_path, context):
    """ Export subobjects recursively.
    """
    exporter = queryMultiAdapter((obj, context), IBody)
    path = '%s%s' % (parent_path, obj.getId().replace(' ', '_'))
    if exporter:
        if exporter.name:
            path = '%s%s' % (parent_path, exporter.name)
        filename = '%s%s' % (path, exporter.suffix)
        body = exporter.body
        if body is not None:
            context.writeDataFile(filename, body, exporter.mime_type)

    if getattr(obj, 'objectValues', False):
        for sub in obj.objectValues():
            exportObjects(sub, path + '/', context)


def importObjects(obj, parent_path, context):
    """ Import subobjects recursively.
    """
    importer = queryMultiAdapter((obj, context), IBody)
    path = '%s%s' % (parent_path, obj.getId().replace(' ', '_'))
    __traceback_info__ = path
    if importer:
        if importer.name:
            path = '%s%s' % (parent_path, importer.name)
        filename = '%s%s' % (path, importer.suffix)
        body = context.readDataFile(filename)
        if body is not None:
            importer.filename = filename  # for error reporting
            importer.body = body

    if getattr(obj, 'objectValues', False):
        for sub in obj.objectValues():
            importObjects(sub, path + '/', context)


def _computeTopologicalSort(steps):
    result = []
    graph = [(x['id'], x['dependencies']) for x in steps]

    unresolved = []

    while 1:
        for node, edges in graph:

            after = -1
            resolved = 0

            for edge in edges:

                if edge in result:
                    resolved += 1
                    after = max(after, result.index(edge))

            if len(edges) > resolved:
                unresolved.append((node, edges))
            else:
                result.insert(after + 1, node)

        if not unresolved:
            break
        if len(unresolved) == len(graph):
            # Nothing was resolved in this loop. There must be circular or
            # missing dependencies. Just add them to the end. We can't
            # raise an error, because checkComplete relies on this method.
            logger = getLogger('GenericSetup')
            log_msg = 'There are unresolved or circular dependencies. '\
                      'Graphviz diagram:: digraph dependencies {'
            for step in steps:
                step_id = step['id']
                for dependency in step['dependencies']:
                    log_msg += '"%s" -> "%s"; ' % (step_id, dependency)
                if not step['dependencies']:
                    log_msg += '"%s";' % step_id
            for unresolved_key, _ignore in unresolved:
                log_msg += '"%s" [color=red,style=filled]; ' % unresolved_key
            log_msg += '}'
            logger.warning(log_msg)

            for node, edges in unresolved:
                result.append(node)
            break
        graph = unresolved
        unresolved = []

    return result


def _getProductPath(product_name):
    """ Return the absolute path of the product's directory.
    """
    try:
        # BBB: for GenericSetup 1.1 style product names
        product = __import__('Products.%s' % product_name, globals(), {},
                             ['initialize'])
    except ImportError:
        try:
            product = __import__(product_name, globals(), {}, ['initialize'])
        except ImportError:
            raise ValueError('Not a valid product name: %s'
                             % product_name)

    return product.__path__[0]
