"""the facets box and some basic facets

:organization: Logilab

:copyright: 2008-2010 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"

from simplejson import dumps

from logilab.mtconverter import xml_escape

from cubicweb.appobject import objectify_selector

from cubicweb.selectors import (non_final_entity, two_lines_rset,

                                match_context_prop, yes, relation_possible)

from cubicweb.web.box import BoxTemplate

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

                                prepare_facets_rqlst, filter_hiddens, _cleanup_rqlst,

                                _prepare_vocabulary_rqlst)

@objectify_selector

def contextview_selector(cls, req, rset=None, 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'

    __select__ = (((non_final_entity() & two_lines_rset())

                   | contextview_selector()

                   ) & match_context_prop())

    context = 'left'

    title = _('boxes_filter_box')

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

    order = 1

    roundcorners = True

    needs_css = 'cubicweb.facets.css'

    needs_js = ('cubicweb.ajax.js', 'cubicweb.facets.js')

    bk_linkbox_template = u'<div class="facetTitle">%s</div>'

    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 and view.paginable

        return rset, vid, divid, paginate

    def call(self, view=None):

        req = self.req

        req.add_js( self.needs_js )

        req.add_css( self.needs_css)

        if self.roundcorners:

            req.html_headers.add_onload('jQuery(".facet").corner("tl br 10px");')

        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:

            vid = req.form.get('vid')

        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

            if self.bk_linkbox_template:

                self.display_bookmark_link(rset)

            w = self.w

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

                divid, xml_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'):

                if param in req.form:

                    hiddens[param] = req.form[param]

            filter_hiddens(w, **hiddens)

            for wdg in widgets:

                wdg.render(w=self.w)

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

        finally:

            rqlst.recover()

    def display_bookmark_link(self, rset):

        eschema = self.schema.eschema('Bookmark')

        if eschema.has_perm(self.req, 'add'):

            bk_path = 'view?rql=%s' % rset.printable_rql()

            bk_title = self.req._('my custom search')

            linkto = 'bookmarked_by:%s:subject' % self.req.user.eid

            bk_add_url = self.build_url('add/Bookmark', path=bk_path, title=bk_title, __linkto=linkto)

            bk_base_url = self.build_url('add/Bookmark', title=bk_title, __linkto=linkto)

            bk_link = u'<a cubicweb:target="%s" id="facetBkLink" href="%s">%s</a>' % (

                    xml_escape(bk_base_url),

                    xml_escape(bk_add_url),

                    self.req._('bookmark this search'))

            self.w(self.bk_linkbox_template % bk_link)

    def get_facets(self, rset, mainvar):

        return self.vreg['facets'].possible_vobjects(self.req, rset=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'

    __select__ = yes()

    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)

    def possible_values(self):

        """return a list of possible values (as string since it's used to

        compare to a form value in javascript) for this facet

        """

        rqlst = self.rqlst

        rqlst.save_state()

        try:

            _cleanup_rqlst(rqlst, self.filtered_variable)

            etype_var = _prepare_vocabulary_rqlst(rqlst, self.filtered_variable, self.rtype, self.role)

            attrvar = rqlst.make_variable()

            rqlst.add_selected(attrvar)

            rqlst.add_relation(etype_var, 'name', attrvar)

            return [etype for _, etype in self.rqlexec(rqlst.as_string())]

        finally:

            rqlst.recover()

class HasTextFacet(AbstractFacet):

    __select__ = relation_possible('has_text', 'subject') & match_context_prop()

    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')