##############################################################################
#
# Copyright (c) 2001 Zope Corporation and Contributors. All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.0 (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
#
##############################################################################
""" CMFDefault portal_metadata tool.

$Id: MetadataTool.py,v 1.20.20.2 2004/08/07 13:31:28 jens Exp $
"""

from OFS.SimpleItem import SimpleItem
from Products.CMFCore.utils import UniqueObject
from Globals import PersistentMapping

from Globals import InitializeClass, DTMLFile
from AccessControl import ClassSecurityInfo, getSecurityManager
from Products.CMFCore.CMFCorePermissions import View
from Products.CMFCore.CMFCorePermissions import ManagePortal
from Products.CMFCore.CMFCorePermissions import ModifyPortalContent
from Products.CMFCore.ActionProviderBase import ActionProviderBase
from utils import _dtmldir

from Products.CMFCore.interfaces.portal_metadata \
        import portal_metadata as IMetadataTool


class MetadataElementPolicy( SimpleItem ):
    """
        Represent a type-specific policy about a particular DCMI element.
    """

    security = ClassSecurityInfo()
    #
    #   Default values.
    #
    is_required         = 0
    supply_default      = 0
    default_value       = ''
    enforce_vocabulary  = 0
    allowed_vocabulary  = ()

    def __init__( self, is_multi_valued=0 ):
        self.is_multi_valued    = not not is_multi_valued

    #
    #   Mutator.
    #
    security.declareProtected(ManagePortal , 'edit')
    def edit( self
            , is_required
            , supply_default
            , default_value
            , enforce_vocabulary
            , allowed_vocabulary
            ):
        self.is_required        = not not is_required
        self.supply_default     = not not supply_default
        self.default_value      = default_value
        self.enforce_vocabulary = not not enforce_vocabulary
        self.allowed_vocabulary = tuple( allowed_vocabulary )

    #
    #   Query interface
    #
    security.declareProtected(View , 'isMultiValued')
    def isMultiValued( self ):
        """
            Can this element hold multiple values?
        """
        return self.is_multi_valued

    security.declareProtected(View , 'isRequired')
    def isRequired( self ):
        """
            Must this element be supplied?
        """
        return self.is_required

    security.declareProtected(View , 'supplyDefault')
    def supplyDefault( self ):
        """
            Should the tool supply a default?
        """
        return self.supply_default

    security.declareProtected(View , 'defaultValue')
    def defaultValue( self ):
        """
            If so, what is the default?
        """
        return self.default_value

    security.declareProtected(View , 'enforceVocabulary')
    def enforceVocabulary( self ):
        """
        """
        return self.enforce_vocabulary

    security.declareProtected(View , 'allowedVocabulary')
    def allowedVocabulary( self ):
        """
        """
        return self.allowed_vocabulary

InitializeClass( MetadataElementPolicy )


DEFAULT_ELEMENT_SPECS = ( ( 'Title', 0 )
                        , ( 'Description', 0 )
                        , ( 'Subject', 1 )
                        , ( 'Format', 0 )
                        , ( 'Language', 0 )
                        , ( 'Rights', 0 )
                        )

class ElementSpec( SimpleItem ):
    """
        Represent all the tool knows about a single metadata element.
    """
    security = ClassSecurityInfo()

    #
    #   Default values.
    #
    is_multi_valued = 0

    def __init__( self, is_multi_valued ):
        self.is_multi_valued  = is_multi_valued
        self.policies         = PersistentMapping()
        self.policies[ None ] = self._makePolicy()  # set default policy


    security.declarePrivate( '_makePolicy' )
    def _makePolicy( self ):
        return MetadataElementPolicy( self.is_multi_valued )

    security.declareProtected(View , 'isMultiValued')
    def isMultiValued( self ):
        """
            Is this element multi-valued?
        """
        return self.is_multi_valued

    security.declareProtected(View , 'getPolicy')
    def getPolicy( self, typ=None ):
        """
            Find the policy this element for objects whose type
            object name is 'typ';  return a default, if none found.
        """
        try:
            return self.policies[ typ ].__of__(self)
        except KeyError:
            return self.policies[ None ]

    security.declareProtected(View , 'listPolicies')
    def listPolicies( self ):
        """
            Return a list of all policies for this element.
        """
        res = []
        for k, v in self.policies.items():
            res.append((k, v.__of__(self)))
        return res

    security.declareProtected(ManagePortal , 'addPolicy')
    def addPolicy( self, typ ):
        """
            Add a policy to this element for objects whose type
            object name is 'typ'.
        """
        if typ is None:
            raise MetadataError, "Can't replace default policy."

        if self.policies.has_key( typ ):
            raise MetadataError, "Existing policy for content type:" + typ

        self.policies[ typ ] = self._makePolicy()

    security.declareProtected(ManagePortal, 'removePolicy')
    def removePolicy( self, typ ):
        """
            Remove the policy from this element for objects whose type
            object name is 'typ' (*not* the default, however).
        """
        if typ is None:
            raise MetadataError, "Can't remove default policy."
        del self.policies[ typ ]

InitializeClass( ElementSpec )

class MetadataError( Exception ):
    pass

class MetadataTool( UniqueObject, SimpleItem, ActionProviderBase ):

    __implements__ = (IMetadataTool, ActionProviderBase.__implements__)

    id = 'portal_metadata'
    meta_type = 'Default Metadata Tool'
    _actions = ()

    #
    #   Default values.
    #
    publisher           = ''
    element_specs       = None
    #initial_values_hook = None
    #validation_hook     = None

    security = ClassSecurityInfo()

    def __init__( self
                , publisher=None
               #, initial_values_hook=None
               #, validation_hook=None
                , element_specs=DEFAULT_ELEMENT_SPECS
                ):

        self.editProperties( publisher
                          #, initial_values_hook
                          #, validation_hook
                           )

        self.element_specs = PersistentMapping()

        for name, is_multi_valued in element_specs:
            self.element_specs[ name ] = ElementSpec( is_multi_valued )

    #
    #   ZMI methods
    #
    manage_options = ( ActionProviderBase.manage_options +
                     ( { 'label'      : 'Overview'
                         , 'action'     : 'manage_overview'
                         }
                       , { 'label'      : 'Properties'
                         , 'action'     : 'propertiesForm'
                         }
                       , { 'label'      : 'Elements'
                         , 'action'     : 'elementPoliciesForm'
                         }
            # TODO     , { 'label'      : 'Types'
            #            , 'action'     : 'typesForm'
            #            }
                       )
                     + SimpleItem.manage_options
                     )

    security.declareProtected(ManagePortal, 'manage_overview')
    manage_overview = DTMLFile( 'explainMetadataTool', _dtmldir )

    security.declareProtected(ManagePortal, 'propertiesForm')
    propertiesForm = DTMLFile( 'metadataProperties', _dtmldir )

    security.declareProtected(ManagePortal, 'editProperties')
    def editProperties( self
                      , publisher=None
               # TODO , initial_values_hook=None
               # TODO , validation_hook=None
                      , REQUEST=None
                      ):
        """
            Form handler for "tool-wide" properties (including list of
            metadata elements).
        """
        if publisher is not None:
            self.publisher = publisher

        # TODO self.initial_values_hook = initial_values_hook
        # TODO self.validation_hook = validation_hook

        if REQUEST is not None:
            REQUEST[ 'RESPONSE' ].redirect( self.absolute_url()
                                        + '/propertiesForm'
                                        + '?manage_tabs_message=Tool+updated.'
                                        )

    security.declareProtected(ManagePortal, 'elementPoliciesForm')
    elementPoliciesForm = DTMLFile( 'metadataElementPolicies', _dtmldir )

    security.declareProtected(ManagePortal, 'addElementPolicy')
    def addElementPolicy( self
                        , element
                        , content_type
                        , is_required
                        , supply_default
                        , default_value
                        , enforce_vocabulary
                        , allowed_vocabulary
                        , REQUEST=None
                        ):
        """
            Add a type-specific policy for one of our elements.
        """
        if content_type == '<default>':
            content_type = None

        spec = self.getElementSpec( element )
        spec.addPolicy( content_type )
        policy = spec.getPolicy( content_type )
        policy.edit( is_required
                   , supply_default
                   , default_value
                   , enforce_vocabulary
                   , allowed_vocabulary
                   )
        if REQUEST is not None:
            REQUEST[ 'RESPONSE' ].redirect( self.absolute_url()
               + '/elementPoliciesForm'
               + '?element=' + element
               + '&manage_tabs_message=Policy+added.'
               )

    security.declareProtected(ManagePortal, 'removeElementPolicy')
    def removeElementPolicy( self
                           , element
                           , content_type
                           , REQUEST=None
                           ):
        """
            Remvoe a type-specific policy for one of our elements.
        """
        if content_type == '<default>':
            content_type = None

        spec = self.getElementSpec( element )
        spec.removePolicy( content_type )
        if REQUEST is not None:
            REQUEST[ 'RESPONSE' ].redirect( self.absolute_url()
               + '/elementPoliciesForm'
               + '?element=' + element
               + '&manage_tabs_message=Policy+removed.'
               )

    security.declareProtected(ManagePortal, 'updateElementPolicy')
    def updateElementPolicy( self
                           , element
                           , content_type
                           , is_required
                           , supply_default
                           , default_value
                           , enforce_vocabulary
                           , allowed_vocabulary
                           , REQUEST=None
                           ):
        """
            Update a policy for one of our elements ('content_type'
            will be '<default>' when we edit the default).
        """
        if content_type == '<default>':
            content_type = None
        spec = self.getElementSpec( element )
        policy = spec.getPolicy( content_type )
        policy.edit( is_required
                   , supply_default
                   , default_value
                   , enforce_vocabulary
                   , allowed_vocabulary
                   )
        if REQUEST is not None:
            REQUEST[ 'RESPONSE' ].redirect( self.absolute_url()
               + '/elementPoliciesForm'
               + '?element=' + element
               + '&manage_tabs_message=Policy+updated.'
               )


    #
    #   Element spec manipulation.
    #
    security.declareProtected(ManagePortal, 'listElementSpecs')
    def listElementSpecs( self ):
        """
            Return a list of ElementSpecs representing
            the elements managed by the tool.
        """
        res = []
        for k, v in self.element_specs.items():
            res.append((k, v.__of__(self)))
        return res

    security.declareProtected(ManagePortal, 'getElementSpec')
    def getElementSpec( self, element ):
        """
            Return an ElementSpec representing the tool's knowledge
            of 'element'.
        """
        return self.element_specs[ element ].__of__( self )

    security.declareProtected(ManagePortal, 'addElementSpec')
    def addElementSpec( self, element, is_multi_valued, REQUEST=None ):
        """
            Add 'element' to our list of managed elements.
        """
        # Don't replace.
        if self.element_specs.has_key( element ):
            return

        self.element_specs[ element ] = ElementSpec( is_multi_valued )

        if REQUEST is not None:
            REQUEST[ 'RESPONSE' ].redirect( self.absolute_url()
               + '/propertiesForm'
               + '?manage_tabs_message=Element+' + element + '+added.'
               )

    security.declareProtected(ManagePortal, 'removeElementSpec')
    def removeElementSpec( self, element, REQUEST=None ):
        """
            Remove 'element' from our list of managed elements.
        """
        del self.element_specs[ element ]

        if REQUEST is not None:
            REQUEST[ 'RESPONSE' ].redirect( self.absolute_url()
               + '/propertiesForm'
               + '?manage_tabs_message=Element+' + element + '+removed.'
               )

    security.declareProtected(ManagePortal, 'listPolicies')
    def listPolicies( self, typ=None ):
        """
            Show all policies for a given content type, or the default
            if None.
        """
        result = []
        for element, spec in self.listElementSpecs():
            result.append( ( element, spec.getPolicy( typ ) ) )
        return result

    #
    #   'portal_metadata' interface
    #
    security.declarePrivate( 'getFullName' )
    def getFullName( self, userid ):
        """
            Convert an internal userid to a "formal" name, if
            possible, perhaps using the 'portal_membership' tool.

            Used to map userid's for Creator, Contributor DCMI
            queries.
        """
        return userid   # TODO: do lookup here

    security.declarePublic( 'getPublisher' )
    def getPublisher( self ):
        """
            Return the "formal" name of the publisher of the
            portal.
        """
        return self.publisher

    security.declarePublic( 'listAllowedVocabulary' )
    def listAllowedVocabulary( self, element, content=None, content_type=None ):
        """
            List allowed keywords for a given portal_type, or all
            possible keywords if none supplied.
        """
        spec = self.getElementSpec( element )
        if content_type is None and content:
            content_type = content.getPortalTypeName()
        return spec.getPolicy( content_type ).allowedVocabulary()

    security.declarePublic( 'listAllowedSubjects' )
    def listAllowedSubjects( self, content=None, content_type=None ):
        """
            List allowed keywords for a given portal_type, or all
            possible keywords if none supplied.
        """
        return self.listAllowedVocabulary( 'Subject', content, content_type )

    security.declarePublic( 'listAllowedFormats' )
    def listAllowedFormats( self, content=None, content_type=None ):
        """
            List the allowed 'Content-type' values for a particular
            portal_type, or all possible formats if none supplied.
        """
        return self.listAllowedVocabulary( 'Format', content, content_type )

    security.declarePublic( 'listAllowedLanguages' )
    def listAllowedLanguages( self, content=None, content_type=None ):
        """
            List the allowed language values.
        """
        return self.listAllowedVocabulary( 'Language', content, content_type )

    security.declarePublic( 'listAllowedRights' )
    def listAllowedRights( self, content=None, content_type=None ):
        """
            List the allowed values for a "Rights"
            selection list;  this gets especially important where
            syndication is involved.
        """
        return self.listAllowedVocabulary( 'Rights', content, content_type )

    security.declareProtected(ModifyPortalContent, 'setInitialMetadata')
    def setInitialMetadata( self, content ):
        """
            Set initial values for content metatdata, supplying
            any site-specific defaults.
        """
        for element, policy in self.listPolicies(content.getPortalTypeName()):

            if not getattr( content, element )():

                if policy.supplyDefault():
                    setter = getattr( content, 'set%s' % element )
                    setter( policy.defaultValue() )
                elif policy.isRequired():
                    raise MetadataError, \
                          'Metadata element %s is required.' % element

        # TODO:  Call initial_values_hook, if present


    security.declareProtected(View, 'validateMetadata')
    def validateMetadata( self, content ):
        """
            Enforce portal-wide policies about DCI, e.g.,
            requiring non-empty title/description, etc.  Called
            by the CMF immediately before saving changes to the
            metadata of an object.
        """
        for element, policy in self.listPolicies(content.getPortalTypeName()):

            value = getattr( content, element )()
            if not value and policy.isRequired():
                raise MetadataError, \
                        'Metadata element %s is required.' % element

            if value and policy.enforceVocabulary():
                values = policy.isMultiValued() and value or [ value ]
                for value in values:
                    if not value in policy.allowedVocabulary():
                        raise MetadataError, \
                        'Value %s is not in allowed vocabulary for ' \
                        'metadata element %s.' % ( value, element )

        # TODO:  Call validation_hook, if present

InitializeClass( MetadataTool )
