"""the facets box and some basic facets

:organization: Logilab

:copyright: 2008 LOGILAB S.A. (Paris, FRANCE), all rights reserved.

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

"""

__docformat__ = "restructuredtext en"

from simplejson import dumps

from logilab.mtconverter import html_escape

from cubicweb.common.selectors import (chainfirst, chainall, nfentity_selector,

                                    twolinerset_selector, contextprop_selector,

                                    yes_selector, one_has_relation_selector)

from cubicweb.web.box import BoxTemplate

from cubicweb.web.facet import (AbstractFacet, VocabularyFacet, FacetStringWidget,

                             RelationFacet, prepare_facets_rqlst, filter_hiddens)

def contextview_selector(cls, req, rset, row=None, col=None, view=None,

                         **kwargs):

    if view and getattr(view, 'filter_box_context_info', lambda: None)():

        return 1

    return 0    

class FilterBox(BoxTemplate):

    """filter results of a query"""

    id = 'filter_box'

    __selectors__ = (chainfirst(contextview_selector,

                                chainall(nfentity_selector, twolinerset_selector)),

                     contextprop_selector)

    context = 'left'

    title = _('boxes_filter_box')

    visible = True # functionality provided by the search box by default

    order = 1

    def facetargs(self):

        """this method returns the list of extra arguments that should

        be used by the facet

        """

        return {}

    def _get_context(self, view):

        context = getattr(view, 'filter_box_context_info', lambda: None)()

        if context:

            rset, vid, divid, paginate = context

        else:

            rset = self.rset

            vid, divid = None, 'pageContent'

            paginate = view.need_navigation

        return rset, vid, divid, paginate

    def call(self, view=None):

        rset, vid, divid, paginate = self._get_context(view)

        if rset.rowcount < 2: # XXX done by selectors, though maybe necessary when rset has been hijacked

            return

        if vid is None:

        rqlst = rset.syntax_tree()

        rqlst.save_state()

        try:

            mainvar, baserql = prepare_facets_rqlst(rqlst, rset.args)

            widgets = []

            for facet in self.get_facets(rset, mainvar):

                if facet.propval('visible'):

                    wdg = facet.get_widget()

                    if wdg is not None:

                        widgets.append(wdg)

            if not widgets:

                return

            w = self.w

            w(u'<form method="post" id="%sForm" cubicweb:facetargs="%s" action="">'  % (

                divid, html_escape(dumps([divid, vid, paginate, self.facetargs()]))))

            w(u'<fieldset>')

            hiddens = {'facets': ','.join(wdg.facet.id for wdg in widgets),

                       'baserql': baserql}

            for param in ('subvid', 'vtitle'):

            filter_hiddens(w, **hiddens)

            for wdg in widgets:

                wdg.render(w=self.w)

            w(u'</fieldset>\n</form>\n')

        finally:

            rqlst.recover()

            print 'after facets', rqlst

    def get_facets(self, rset, mainvar):

        return self.vreg.possible_vobjects('facets', self.req, rset,

                                           context='facetbox',

                                           filtered_variable=mainvar)

# facets ######################################################################

class CreatedByFacet(RelationFacet):

    id = 'created_by-facet'

    rtype = 'created_by'

    target_attr = 'login'

class InGroupFacet(RelationFacet):

    id = 'in_group-facet'

    rtype = 'in_group'

    target_attr = 'name'

class InStateFacet(RelationFacet):

    id = 'in_state-facet'

    rtype = 'in_state'

    target_attr = 'name'

# inherit from RelationFacet to benefit from its possible_values implementation

class ETypeFacet(RelationFacet):

    id = 'etype-facet'

    __selectors__ = (yes_selector,)

    order = 1

    rtype = 'is'

    target_attr = 'name'

    @property

    def title(self):

        return self.req._('entity type')

    def vocabulary(self):

        """return vocabulary for this facet, eg a list of 2-uple (label, value)

        """

        etypes = self.rset.column_types(0)

        return sorted((self.req._(etype), etype) for etype in etypes)

    def add_rql_restrictions(self):

        """add restriction for this facet into the rql syntax tree"""

        value = self.req.form.get(self.id)

        if not value:

            return

        self.rqlst.add_type_restriction(self.filtered_variable, value)

class HasTextFacet(AbstractFacet):

    __selectors__ = (one_has_relation_selector, contextprop_selector)

    id = 'has_text-facet'

    rtype = 'has_text'

    role = 'subject'

    order = 0

    @property

    def title(self):

        return self.req._('has_text')

    def get_widget(self):

        """return the widget instance to use to display this facet

        default implentation expects a .vocabulary method on the facet and

        return a combobox displaying this vocabulary

        """

        return FacetStringWidget(self)

    def add_rql_restrictions(self):

        """add restriction for this facet into the rql syntax tree"""

        value = self.req.form.get(self.id)

        if not value:

            return

        self.rqlst.add_constant_restriction(self.filtered_variable, 'has_text', value, 'String')