# copyright 2003-2016 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
#
# This file is part of CubicWeb.
#
# CubicWeb is free software: you can redistribute it and/or modify it under the
# terms of the GNU Lesser General Public License as published by the Free
# Software Foundation, either version 2.1 of the License, or (at your option)
# any later version.
#
# CubicWeb is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
# details.
#
# You should have received a copy of the GNU Lesser General Public License along
# with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.
"""management and error screens"""

from cubicweb import _

from time import strftime, localtime

from logilab.mtconverter import xml_escape

from cubicweb.predicates import none_rset, match_user_groups
from cubicweb.view import StartupView
from cubicweb.web.views import actions, tabs


def dict_to_html(w, dict):
    # XHTML doesn't allow emtpy <ul> nodes
    if dict:
        w(u'<ul>')
        for key in sorted(dict):
            w(u'<li><span>%s</span>: <span>%s</span></li>' % (
                xml_escape(str(key)), xml_escape(repr(dict[key]))))
        w(u'</ul>')


class SiteInfoAction(actions.ManagersAction):
    __regid__ = 'siteinfo'
    __select__ = match_user_groups('users', 'managers')
    title = _('Site information')
    category = 'manage'
    order = 1000


class SiteInfoView(tabs.TabsMixin, StartupView):
    __regid__ = 'siteinfo'
    title = _('Site information')
    tabs = [_('info'), _('registry'), _('gc')]
    default_tab = 'info'

    def call(self, **kwargs):
        """The default view representing the instance's management"""
        self.w(u'<h1>%s</h1>' % self._cw._(self.title))
        self.render_tabs(self.tabs, self.default_tab)


class ProcessInformationView(StartupView):
    """display various web server /repository information"""
    __regid__ = 'info'
    __select__ = none_rset() & match_user_groups('managers', 'users')

    title = _('server information')
    cache_max_age = 0

    def call(self, **kwargs):
        req = self._cw
        dtformat = req.property_value('ui.datetime-format')
        _ = req._
        w = self.w
        repo = req.cnx.repo
        # generic instance information
        w(u'<h2>%s</h2>' % _('Instance'))
        pyvalue = ((_('config type'), self._cw.vreg.config.name),
                   (_('config mode'), self._cw.vreg.config.mode),
                   (_('instance home'), self._cw.vreg.config.apphome))
        self.wview('pyvaltable', pyvalue=pyvalue, header_column_idx=0)
        vcconf = repo.get_versions()
        w(u'<h3>%s</h3>' % _('versions configuration'))
        missing = _('no version information')
        pyvalue = [('CubicWeb', vcconf.get('cubicweb', missing))]
        pyvalue += [(cube, vcconf.get(cube, missing))
                    for cube in sorted(self._cw.vreg.config.cubes())]
        self.wview('pyvaltable', pyvalue=pyvalue, header_column_idx=0)
        # repository information
        w(u'<h2>%s</h2>' % _('Repository'))
        w(u'<h3>%s</h3>' % _('resources usage'))
        stats = self._cw.call_service('repo_stats')
        stats['threads'] = ', '.join(sorted(stats['threads']))
        for k in stats:
            if k == 'type_cache_size':
                continue
            if k.endswith('_cache_size'):
                stats[k] = '%s / %s' % (stats[k]['size'], stats[k]['maxsize'])
        def format_stat(sname, sval):
            return '%s %s' % (xml_escape(str(sval)),
                              sname.endswith('percent') and '%' or '')
        pyvalue = [(sname, format_stat(sname, sval))
                    for sname, sval in sorted(stats.items())]
        self.wview('pyvaltable', pyvalue=pyvalue, header_column_idx=0)
        # web server information
        w(u'<h2>%s</h2>' % _('Web server'))
        pyvalue = ((_('base url'), req.base_url()),
                   (_('data directory url'), req.datadir_url))
        self.wview('pyvaltable', pyvalue=pyvalue, header_column_idx=0)
        from cubicweb.web.application import SESSION_MANAGER
        if SESSION_MANAGER is not None and req.user.is_in_group('managers'):
            sessions = SESSION_MANAGER.current_sessions()
            w(u'<h3>%s</h3>' % _('opened web sessions'))
            if sessions:
                w(u'<ul>')
                for session in sessions:
                    last_usage_time = session.mtime
                    w(u'<li>%s (%s: %s)<br/>' % (
                        session.sessionid,
                        _('last usage'),
                        strftime(dtformat, localtime(last_usage_time))))
                    dict_to_html(w, session.data)
                    w(u'</li>')
                w(u'</ul>')
            else:
                w(u'<p>%s</p>' % _('no web sessions found'))



class RegistryView(StartupView):
    """display vregistry content"""
    __regid__ = 'registry'
    __select__ = StartupView.__select__ & match_user_groups('managers')
    title = _('registry')
    cache_max_age = 0

    def call(self, **kwargs):
        self.w(u'<h2>%s</h2>' % self._cw._("Registry's content"))
        keys = sorted(self._cw.vreg)
        url = xml_escape(self._cw.url())
        self.w(u'<p>%s</p>\n' % ' - '.join('<a href="%s#%s">%s</a>'
                                           % (url, key, key) for key in keys))
        for key in keys:
            if key in ('boxes', 'contentnavigation'): # those are bw compat registries
                continue
            self.w(u'<h3 id="%s">%s</h3>' % (key, key))
            if self._cw.vreg[key]:
                values = sorted(self._cw.vreg[key].items())
                self.wview('pyvaltable', pyvalue=[(key, xml_escape(repr(val)))
                                                  for key, val in values])
            else:
                self.w(u'<p>Empty</p>\n')


class GCView(StartupView):
    """display garbage collector information"""
    __regid__ = 'gc'
    __select__ = StartupView.__select__ & match_user_groups('managers')
    title = _('memory leak debugging')
    cache_max_age = 0

    def call(self, **kwargs):
        stats = self._cw.call_service('repo_gc_stats')
        self.w(u'<h2>%s</h2>' % _('Garbage collection information'))
        self.w(u'<h3>%s</h3>' % self._cw._('Looked up classes'))
        self.wview('pyvaltable', pyvalue=stats['lookupclasses'])
        self.w(u'<h3>%s</h3>' % self._cw._('Most referenced classes'))
        self.wview('pyvaltable', pyvalue=stats['referenced'])
        if stats['unreachable']:
            self.w(u'<h3>%s</h3>' % self._cw._('Unreachable objects'))
            values = [xml_escape(val) for val in stats['unreachable']]
            self.wview('pyvallist', pyvalue=values)