"""base classes to handle tabbed views

:organization: Logilab

:copyright: 2008-2009 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 logilab.mtconverter import xml_escape

from cubicweb import NoSelectableObject, role

from cubicweb.selectors import partial_has_related_entities

from cubicweb.view import EntityView

from cubicweb.common import tags, uilib

from cubicweb.utils import make_uid

class LazyViewMixin(object):

    """provides two convenience methods for the tab machinery

    can also be used to lazy-load arbitrary views

    caveat : lazyview is not recursive, i.e : you can't (successfully)

    lazyload a view that in turns does the same

    """

    def _prepare_bindings(self, vid, reloadable):

        self.req.add_onload(u"""

  jQuery('#lazy-%(vid)s').bind('%(event)s', function(event) {

     load_now('#lazy-%(vid)s', '#%(vid)s-hole', %(reloadable)s);

  });""" % {'event': 'load_%s' % vid, 'vid': vid,

            'reloadable' : str(reloadable).lower()})

    def lazyview(self, vid, rql=None, eid=None, rset=None, static=False,

                 reloadable=False, show_spinbox=True, w=None):

        """a lazy version of wview

        first version only support lazy viewing for an entity at a time

        """

        assert rql or eid or rset or static, \

            'lazyview wants at least : rql, or an eid, or an rset -- or call it with static=True'

        w = w or self.w

        self.req.add_js('cubicweb.lazy.js')

        urlparams = {'vid' : vid, 'fname' : 'view'}

        if rql:

            urlparams['rql'] = rql

        elif eid:

            urlparams['rql'] = uilib.rql_for_eid(eid)

        elif rset:

            urlparams['rql'] = rset.printable_rql()

        w(u'<div id="lazy-%s" cubicweb:loadurl="%s">' % (

            vid, xml_escape(self.build_url('json', **urlparams))))

        if show_spinbox:

            w(u'<img src="data/loading.gif" id="%s-hole" alt="%s"/>'

              % (vid, self.req._('loading')))

        w(u'</div>')

        self._prepare_bindings(vid, reloadable)

    def forceview(self, vid):

        """trigger an event that will force immediate loading of the view

        on dom readyness

        """

        self.req.add_js('cubicweb.lazy.js')

        self.req.add_onload("trigger_load('%s');" % vid)

class TabsMixin(LazyViewMixin):

    """a tab mixin

    """

    @property

    def cookie_name(self):

        return str('%s_active_tab' % self.config.appid)

    def active_tab(self, tabs, default):

        formtab = self.req.form.get('tab')

        if formtab in tabs:

            return formtab

        cookies = self.req.get_cookie()

        cookiename = self.cookie_name

        activetab = cookies.get(cookiename)

        if activetab is None:

            cookies[cookiename] = default

            self.req.set_cookie(cookies, cookiename)

            tab = default

        else:

            tab = activetab.value

        return tab in tabs and tab or default

    def prune_tabs(self, tabs):

        selected_tabs = []

        for tab in tabs:

            try:

                self.vreg['views'].select(tab, self.req, rset=self.rset)

                selected_tabs.append(tab)

            except NoSelectableObject:

                continue

        return selected_tabs

    def render_tabs(self, tabs, default, entity=None):

        # delegate to the default tab if there is more than one entity

        # in the result set (tabs are pretty useless there)

        if entity and len(self.rset) > 1:

            entity.view(default, w=self.w)

            return

        self.req.add_css('ui.tabs.css')

        self.req.add_js(('ui.core.js', 'ui.tabs.js',

                         'cubicweb.ajax.js', 'cubicweb.tabs.js', 'cubicweb.lazy.js'))

        # prune tabs : not all are to be shown

        tabs = self.prune_tabs(tabs)

        # select a tab

        active_tab = self.active_tab(tabs, default)

        # build the html structure

        w = self.w

        uid = entity and entity.eid or make_uid('tab')

        w(u'<div id="entity-tabs-%s">' % uid)

        w(u'<ul>')

        for tab in tabs:

            w(u'<li>')

            w(u'<a href="#%s">' % tab)

            w(u'<span onclick="set_tab(\'%s\', \'%s\')">' % (tab, self.cookie_name))

            w(self.req._(tab))

            w(u'</span>')

            w(u'</a>')

            w(u'</li>')

        w(u'</ul>')

        w(u'</div>')

        for tab in tabs:

            w(u'<div id="%s">' % tab)

            if entity:

                self.lazyview(tab, eid=entity.eid)

            else:

                self.lazyview(tab, static=True)

            w(u'</div>')

        # call the set_tab() JS function *after* each tab is generated

        # because the callback binding needs to be done before

        # XXX make work history: true

        self.req.add_onload(u"""

  jQuery('#entity-tabs-%(eeid)s > ul').tabs( { selected: %(tabindex)s });

  set_tab('%(vid)s', '%(cookiename)s');

""" % {'tabindex'   : tabs.index(active_tab),

       'vid'        : active_tab,

       'eeid'       : (entity and entity.eid or uid),

       'cookiename' : self.cookie_name})

class EntityRelationView(EntityView):

    """view displaying entity related stuff.

    Such a view _must_ provide the rtype, target and vid attributes :

    Example :

    class ProjectScreenshotsView(EntityRelationView):

        '''display project's screenshots'''

        id = title = _('projectscreenshots')

        __select__ = EntityRelationView.__select__ & implements('Project')

        rtype = 'screenshot'

        role = 'subject'

        vid = 'gallery'

    in this example, entities related to project entity by the 'screenshot'

    relation (where the project is subject of the relation) will be displayed

    using the 'gallery' view.

    """

    __select__ = EntityView.__select__ & partial_has_related_entities()

    vid = 'list'

    def cell_call(self, row, col):

        rset = self.entity(row, col).related(self.rtype, role(self))

        self.w(u'<div class="mainInfo">')

        if self.title:

            self.w(tags.h1(self.req._(self.title)))

        self.wview(self.vid, rset, 'noresult')

        self.w(u'</div>')