"""workflow related schemas

:organization: Logilab

:copyright: 2001-2010 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.

:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr

:license: GNU Lesser General Public License, v2.1 - http://www.gnu.org/licenses

"""

__docformat__ = "restructuredtext en"

_ = unicode

from yams.buildobjs import (EntityType, RelationType, SubjectRelation,

                            ObjectRelation, RichString, String)

from cubicweb.schema import RQLConstraint, RQLUniqueConstraint

from cubicweb.schemas import (META_ETYPE_PERMS, META_RTYPE_PERMS,

                              HOOKS_RTYPE_PERMS)

class Workflow(EntityType):

    __permissions__ = META_ETYPE_PERMS

    name = String(required=True, indexed=True, internationalizable=True,

                  maxsize=256)

    description = RichString(fulltextindexed=True, default_format='text/rest',

                             description=_('semantic description of this workflow'))

    workflow_of = SubjectRelation('CWEType', cardinality='+*',

                                  description=_('entity types which may use this workflow'),

                                  constraints=[RQLConstraint('O final FALSE')])

    initial_state = SubjectRelation('State', cardinality='?*',

                                   constraints=[RQLConstraint('O state_of S',

                                                              msg=_('state doesn\'t belong to this workflow'))],

                                   description=_('initial state for this workflow'))

class default_workflow(RelationType):

    """default workflow for an entity type"""

    __permissions__ = META_RTYPE_PERMS

    subject = 'CWEType'

    object = 'Workflow'

    cardinality = '?*'

    constraints = [RQLConstraint('S final FALSE, O workflow_of S',

                                 msg=_('workflow isn\'t a workflow for this type'))]

class State(EntityType):

    """used to associate simple states to an entity type and/or to define

    workflows

    """

    __permissions__ = META_ETYPE_PERMS

    name = String(required=True, indexed=True, internationalizable=True,

                  maxsize=256,

                  constraints=[RQLUniqueConstraint('S name N, S state_of WF, Y state_of WF, Y name N', 'Y',

                                                   _('workflow already have a state of that name'))])

    description = RichString(fulltextindexed=True, default_format='text/rest',

                             description=_('semantic description of this state'))

    # XXX should be on BaseTransition w/ AND/OR selectors when we will

    # implements #345274

    allowed_transition = SubjectRelation('BaseTransition', cardinality='**',

                                         constraints=[RQLConstraint('S state_of WF, O transition_of WF',

                                                                    msg=_('state and transition don\'t belong the the same workflow'))],

                                         description=_('allowed transitions from this state'))

    state_of = SubjectRelation('Workflow', cardinality='1*', composite='object',

                               description=_('workflow to which this state belongs'),

                               constraints=[RQLUniqueConstraint('S name N, Y state_of O, Y name N', 'Y',

                                                                _('workflow already have a state of that name'))])

class BaseTransition(EntityType):

    """abstract base class for transitions"""

    __permissions__ = META_ETYPE_PERMS

    name = String(required=True, indexed=True, internationalizable=True,

                  maxsize=256,

                  constraints=[RQLUniqueConstraint('S name N, S transition_of WF, Y transition_of WF, Y name N', 'Y',

                                                   _('workflow already have a transition of that name'))])

    type = String(vocabulary=(_('normal'), _('auto')), default='normal')

    description = RichString(fulltextindexed=True,

                         description=_('semantic description of this transition'))

    condition = SubjectRelation('RQLExpression', cardinality='*?', composite='subject',

                                description=_('a RQL expression which should return some results, '

                                              'else the transition won\'t be available. '

                                              'This query may use X and U variables '

                                              'that will respectivly represents '

                                              'the current entity and the current user'))

    require_group = SubjectRelation('CWGroup', cardinality='**',

                                    description=_('group in which a user should be to be '

                                                  'allowed to pass this transition'))

    transition_of = SubjectRelation('Workflow', cardinality='1*', composite='object',

                                    description=_('workflow to which this transition belongs'),

                                    constraints=[RQLUniqueConstraint('S name N, Y transition_of O, Y name N', 'Y',

                                                                     _('workflow already have a transition of that name'))])

class Transition(BaseTransition):

    """use to define a transition from one or multiple states to a destination

    states in workflow's definitions.

    """

    __specializes_schema__ = True

    destination_state = SubjectRelation(

        'State', cardinality='1*',

        constraints=[RQLConstraint('S transition_of WF, O state_of WF',

                                   msg=_('state and transition don\'t belong the the same workflow'))],

        description=_('destination state for this transition'))

class WorkflowTransition(BaseTransition):

    """special transition allowing to go through a sub-workflow"""

    __specializes_schema__ = True

    subworkflow = SubjectRelation('Workflow', cardinality='1*',

                                  constraints=[RQLConstraint('S transition_of WF, WF workflow_of ET, O workflow_of ET',

                                                             msg=_('subworkflow isn\'t a workflow for the same types as the transition\'s workflow'))]

                                  )

    # XXX use exit_of and inline it

    subworkflow_exit = SubjectRelation('SubWorkflowExitPoint', cardinality='*1',

                                       composite='subject')

class SubWorkflowExitPoint(EntityType):

    """define how we get out from a sub-workflow"""

    subworkflow_state = SubjectRelation(

        'State', cardinality='1*',

        constraints=[RQLConstraint('T subworkflow_exit S, T subworkflow WF, O state_of WF',

                                   msg=_('exit state must a subworkflow state'))],

        description=_('subworkflow state'))

    destination_state = SubjectRelation(

        'State', cardinality='?*',

        constraints=[RQLConstraint('T subworkflow_exit S, T transition_of WF, O state_of WF',

                                   msg=_('destination state must be in the same workflow as our parent transition'))],

        description=_('destination state. No destination state means that transition '

                      'should go back to the state from which we\'ve entered the '

                      'subworkflow.'))

class TrInfo(EntityType):

    """workflow history item"""

    # 'add' security actually done by hooks

    __permissions__ = {

        'read':   ('managers', 'users', 'guests',), # XXX U has_read_permission O ?

        'add':    ('managers', 'users', 'guests',),

        'delete': (), # XXX should we allow managers to delete TrInfo?

        'update': ('managers', 'owners',),

    }

    from_state = SubjectRelation('State', cardinality='1*')

    to_state = SubjectRelation('State', cardinality='1*')

    # make by_transition optional because we want to allow managers to set

    # entity into an arbitrary state without having to respect wf transition

    by_transition = SubjectRelation('BaseTransition', cardinality='?*')

    comment = RichString(fulltextindexed=True)

    # get actor and date time using owned_by and creation_date

class from_state(RelationType):

    __permissions__ = HOOKS_RTYPE_PERMS.copy()

    inlined = True

class to_state(RelationType):

    __permissions__ = HOOKS_RTYPE_PERMS.copy()

    inlined = True

class by_transition(RelationType):

    # 'add' security actually done by hooks

    __permissions__ = {

        'read':   ('managers', 'users', 'guests',),

        'add':    ('managers', 'users', 'guests',),

        'delete': (),

    }

    inlined = True

class workflow_of(RelationType):

    """link a workflow to one or more entity type"""

    __permissions__ = META_RTYPE_PERMS

class state_of(RelationType):

    """link a state to one or more workflow"""

    __permissions__ = META_RTYPE_PERMS

    inlined = True

class transition_of(RelationType):

    """link a transition to one or more workflow"""

    __permissions__ = META_RTYPE_PERMS

    inlined = True

class subworkflow(RelationType):

    """link a transition to one or more workflow"""

    __permissions__ = META_RTYPE_PERMS

    inlined = True

class exit_point(RelationType):

    """link a transition to one or more workflow"""

    __permissions__ = META_RTYPE_PERMS

class subworkflow_state(RelationType):

    """link a transition to one or more workflow"""

    __permissions__ = META_RTYPE_PERMS

    inlined = True

class initial_state(RelationType):

    """indicate which state should be used by default when an entity using

    states is created

    """

    __permissions__ = META_RTYPE_PERMS

    inlined = True

class destination_state(RelationType):

    """destination state of a transition"""

    __permissions__ = META_RTYPE_PERMS

    inlined = True

class allowed_transition(RelationType):

    """allowed transitions from this state"""

    __permissions__ = META_RTYPE_PERMS

# "abstract" relations, set by WorkflowableEntityType ##########################

class custom_workflow(RelationType):

    """allow to set a specific workflow for an entity"""

    __permissions__ = META_RTYPE_PERMS

    cardinality = '?*'

    constraints = [RQLConstraint('S is ET, O workflow_of ET',

                                 msg=_('workflow isn\'t a workflow for this type'))]

    object = 'Workflow'

class wf_info_for(RelationType):

    """link a transition information to its object"""

    # 'add' security actually done by hooks

    __permissions__ = {

        'read':   ('managers', 'users', 'guests',),

        'add':    ('managers', 'users', 'guests',),

        'delete': (),

    }

    inlined = True

    cardinality = '1*'

    composite = 'object'

    fulltext_container = composite

    subject = 'TrInfo'

class in_state(RelationType):

    """indicate the current state of an entity"""

    __permissions__ = HOOKS_RTYPE_PERMS

    # not inlined intentionnaly since when using ldap sources, user'state

    # has to be stored outside the CWUser table

    inlined = False

    cardinality = '1*'

    constraints = [RQLConstraint('S is ET, O state_of WF, WF workflow_of ET',

                                 msg=_('state doesn\'t apply to this entity\'s type'))]

    object = 'State'