views.py

# -*- coding: utf-8 -*-
# Copyright The IETF Trust 2009-2020, All Rights Reserved
#
# Portion Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
# All rights reserved. Contact: Pasi Eronen <pasi.eronen@nokia.com>
# 
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions 
# are met:
# 
#  * Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 
#  * Redistributions in binary form must reproduce the above
#    copyright notice, this list of conditions and the following
#    disclaimer in the documentation and/or other materials provided
#    with the distribution.
# 
#  * Neither the name of the Nokia Corporation and/or its
#    subsidiary(-ies) nor the names of its contributors may be used
#    to endorse or promote products derived from this software
#    without specific prior written permission.
# 
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.


import copy
import datetime
import itertools
import io
import json
import math
import os
import re

from tempfile import mkstemp
from collections import OrderedDict, defaultdict
from simple_history.utils import update_change_reason

from django import forms
from django.conf import settings
from django.contrib.auth.decorators import login_required
from django.db.models import Q, Count
from django.http import HttpResponse, HttpResponseRedirect, Http404, JsonResponse
from django.shortcuts import render, redirect, get_object_or_404
from django.template.loader import render_to_string
from django.urls import reverse as urlreverse
from django.utils import timezone
from django.utils.html import escape
from django.views.decorators.cache import cache_page, cache_control

import debug                            # pyflakes:ignore

from ietf.community.models import CommunityList, EmailSubscription
from ietf.community.utils import docs_tracked_by_community_list
from ietf.doc.models import DocTagName, State, DocAlias, RelatedDocument, Document
from ietf.doc.templatetags.ietf_filters import clean_whitespace
from ietf.doc.utils import get_chartering_type, get_tags_for_stream_id
from ietf.doc.utils_charter import charter_name_for_group, replace_charter_of_replaced_group
from ietf.doc.utils_search import prepare_document_table
#
from ietf.group.dot import make_dot
from ietf.group.forms import (GroupForm, StatusUpdateForm, ConcludeGroupForm, StreamEditForm,
                              ManageReviewRequestForm, EmailOpenAssignmentsForm, ReviewerSettingsForm,
                              AddUnavailablePeriodForm, EndUnavailablePeriodForm, ReviewSecretarySettingsForm, )
from ietf.group.mails import email_admin_re_charter, email_personnel_change, email_comment
from ietf.group.models import ( Group, Role, GroupEvent, GroupStateTransitions,
                              ChangeStateGroupEvent, GroupFeatures )
from ietf.group.utils import (get_charter_text, can_manage_group_type, 
                              milestone_reviewer_for_group_type, can_provide_status_update,
                              can_manage_materials, 
                              construct_group_menu_context, get_group_materials,
                              save_group_in_history, can_manage_group, 
                              get_group_or_404, setup_default_community_list_for_group, )                              
#
from ietf.ietfauth.utils import has_role, is_authorized_in_group
from ietf.mailtrigger.utils import gather_relevant_expansions
from ietf.meeting.helpers import get_meeting
from ietf.meeting.utils import group_sessions, add_event_info_to_session_qs
from ietf.name.models import GroupTypeName, StreamName
from ietf.person.models import Email, Person
from ietf.review.models import (ReviewRequest, ReviewAssignment, ReviewerSettings, 
                                ReviewSecretarySettings, UnavailablePeriod )
from ietf.review.policies import get_reviewer_queue_policy
from ietf.review.utils import (can_manage_review_requests_for_team,
                               can_access_review_stats_for_team,

                               extract_revision_ordered_review_requests_for_documents_and_replaced,
                               assign_review_request_to_reviewer,
                               close_review_request,

                               suggested_review_requests_for_team,
                               unavailable_periods_to_list,
                               current_unavailable_periods_for_reviewers,
                               email_reviewer_availability_change,
                               latest_review_assignments_for_reviewers,
                               augment_review_requests_with_events,
                               get_default_filter_re,
                               days_needed_to_fulfill_min_interval_for_reviewers,
                              )
from ietf.doc.models import LastCallDocEvent


from ietf.name.models import ReviewAssignmentStateName
from ietf.utils.mail import send_mail_text, parse_preformatted

from ietf.ietfauth.utils import user_is_person
from ietf.dbtemplate.models import DBTemplate
from ietf.mailtrigger.utils import gather_address_lists
from ietf.mailtrigger.models import Recipient
from ietf.settings import MAILING_LIST_INFO_URL
from ietf.utils.pipe import pipe
from ietf.utils.response import permission_denied
from ietf.utils.text import strip_suffix
from ietf.utils.timezone import datetime_today_start


# --- Helpers ----------------------------------------------------------

def roles(group, role_name):
    return Role.objects.filter(group=group, name=role_name).select_related("email", "person")


def fill_in_charter_info(group, include_drafts=False):
    group.areadirector = getattr(group.ad_role(),'email',None)

    personnel = {}
    for r in Role.objects.filter(group=group).order_by('person__name').select_related("email", "person", "name"):
        if r.name_id not in personnel:
            personnel[r.name_id] = []
        personnel[r.name_id].append(r)

    if group.parent and group.parent.type_id == "area" and group.ad_role() and "ad" not in personnel:
        ad_roles = list(Role.objects.filter(group=group.parent, name="ad", person=group.ad_role().person))
        if ad_roles:
            personnel["ad"] = ad_roles

    group.personnel = []
    for role_name_slug, roles in personnel.items():
        label = roles[0].name.name
        if len(roles) > 1:
            if label.endswith("y"):
                label = label[:-1] + "ies"
            else:
                label += "s"

        group.personnel.append((role_name_slug, label, roles))

    group.personnel.sort(key=lambda t: t[2][0].name.order)

    milestone_state = "charter" if group.state_id == "proposed" else "active"
    group.milestones = group.groupmilestone_set.filter(state=milestone_state)
    if group.uses_milestone_dates:
        group.milestones = group.milestones.order_by('resolved', 'due')
    else:
        group.milestones = group.milestones.order_by('resolved', 'order')

    if group.charter:
        group.charter_text = get_charter_text(group)
    else:
        group.charter_text = "Not chartered yet."

def extract_last_name(role):
    return role.person.name_parts()[3]

def fill_in_wg_roles(group):
    def get_roles(slug, default):
        for role_slug, label, roles in group.personnel:
            if slug == role_slug:
                return roles
        return default

    group.chairs = get_roles("chair", [])
    ads = get_roles("ad", [])
    group.areadirector = ads[0] if ads else None
    group.techadvisors = get_roles("techadv", [])
    group.editors = get_roles("editor", [])
    group.secretaries = get_roles("secr", [])

def fill_in_wg_drafts(group):
    aliases = DocAlias.objects.filter(docs__type="draft", docs__group=group).prefetch_related('docs').order_by("name")
    group.drafts = []
    group.rfcs = []
    for a in aliases:
        if a.name.startswith("draft"):
            group.drafts.append(a)
        else:
            group.rfcs.append(a)
            a.remote_field = RelatedDocument.objects.filter(source=a.document,relationship_id__in=['obs','updates']).distinct()
            a.invrel = RelatedDocument.objects.filter(target=a,relationship_id__in=['obs','updates']).distinct()


def check_group_email_aliases():
    pattern = re.compile(r'expand-(.*?)(-\w+)@.*? +(.*)$')
    tot_count = 0
    good_count = 0
    with io.open(settings.GROUP_VIRTUAL_PATH,"r") as virtual_file:
        for line in virtual_file.readlines():
            m = pattern.match(line)
            tot_count += 1
            if m:
                good_count += 1
            if good_count > 50 and tot_count < 3*good_count:
                return True
    return False


# --- View functions ---------------------------------------------------

def wg_summary_area(request, group_type):
    if group_type != "wg":
        raise Http404
    areas = Group.objects.filter(type="area", state="active").order_by("name")
    for area in areas:
        area.groups = Group.objects.filter(parent=area, type="wg", state="active").order_by("acronym")
        for group in area.groups:
            group.chairs = sorted(roles(group, "chair"), key=extract_last_name)

    areas = [a for a in areas if a.groups]

    return render(request, 'group/1wg-summary.txt',
                  { 'areas': areas },
                  content_type='text/plain; charset=UTF-8')

def wg_summary_acronym(request, group_type):
    if group_type != "wg":
        raise Http404
    areas = Group.objects.filter(type="area", state="active").order_by("name")
    groups = Group.objects.filter(type="wg", state="active").order_by("acronym").select_related("parent")
    for group in groups:
        group.chairs = sorted(roles(group, "chair"), key=extract_last_name)
    return render(request, 'group/1wg-summary-by-acronym.txt',
                  { 'areas': areas,
                    'groups': groups },
                  content_type='text/plain; charset=UTF-8')

@cache_page ( 60 * 60, cache="slowpages" )
def wg_charters(request, group_type):
    if group_type != "wg":
        raise Http404
    areas = Group.objects.filter(type="area", state="active").order_by("name")
    for area in areas:
        area.groups = Group.objects.filter(parent=area, type="wg", state="active").order_by("name")
        for group in area.groups:
            fill_in_charter_info(group)
            fill_in_wg_roles(group)
            fill_in_wg_drafts(group)
    return render(request, 'group/1wg-charters.txt',
                  { 'areas': areas },
                  content_type='text/plain; charset=UTF-8')

@cache_page ( 60 * 60, cache="slowpages" )
def wg_charters_by_acronym(request, group_type):
    if group_type != "wg":
        raise Http404

    groups = Group.objects.filter(type="wg", state="active").exclude(parent=None).order_by("acronym")
    for group in groups:
        fill_in_charter_info(group)
        fill_in_wg_roles(group)
        fill_in_wg_drafts(group)
    return render(request, 'group/1wg-charters-by-acronym.txt',
                  { 'groups': groups },
                  content_type='text/plain; charset=UTF-8')

def active_groups(request, group_type=None):

    if not group_type:
        return active_group_types(request)
    elif group_type == "wg":
        return active_wgs(request)
    elif group_type == "rg":
        return active_rgs(request)
    elif group_type == "ag":
        return active_ags(request)
    elif group_type == "rag":
        return active_rags(request)
    elif group_type == "area":
        return active_areas(request)
    elif group_type == "team":
        return active_teams(request)
    elif group_type == "dir":
        return active_dirs(request)
    elif group_type == "review":
        return active_review_dirs(request)
    elif group_type == "program":
        return active_programs(request)
    else:
        raise Http404

def active_group_types(request):
    grouptypes = GroupTypeName.objects.filter(slug__in=['wg','rg','ag','rag','team','dir','review','area','program']).filter(group__state='active').annotate(group_count=Count('group'))
    return render(request, 'group/active_groups.html', {'grouptypes':grouptypes})

def active_dirs(request):
    dirs = Group.objects.filter(type__in=['dir', 'review'], state="active").order_by("name")
    for group in dirs:
        group.chairs = sorted(roles(group, "chair"), key=extract_last_name)
        group.secretaries = sorted(roles(group, "secr"), key=extract_last_name)
    return render(request, 'group/active_dirs.html', {'dirs' : dirs })

def active_review_dirs(request):
    dirs = Group.objects.filter(type="review", state="active").order_by("name")
    for group in dirs:
        group.chairs = sorted(roles(group, "chair"), key=extract_last_name)
        group.secretaries = sorted(roles(group, "secr"), key=extract_last_name)
    return render(request, 'group/active_review_dirs.html', {'dirs' : dirs })

def active_teams(request):
    teams = Group.objects.filter(type="team", state="active").order_by("name")
    for group in teams:
        group.chairs = sorted(roles(group, "chair"), key=extract_last_name)
    return render(request, 'group/active_teams.html', {'teams' : teams })

def active_programs(request):
    programs = Group.objects.filter(type="program", state="active").order_by("name")
    for group in programs:
        group.leads = sorted(roles(group, "lead"), key=extract_last_name)
    return render(request, 'group/active_programs.html', {'programs' : programs })

def active_areas(request):
        areas = Group.objects.filter(type="area", state="active").order_by("name")  
        return render(request, 'group/active_areas.html', {'areas': areas })

def active_wgs(request):
    areas = Group.objects.filter(type="area", state="active").order_by("name")
    for area in areas:
        # dig out information for template
        area.ads_and_pre_ads = (
            list(area.ads) + list(sorted(roles(area, "pre-ad"), key=extract_last_name))
        )

        area.groups = Group.objects.filter(parent=area, type="wg", state="active").order_by("acronym")
        area.urls = area.groupextresource_set.all().order_by("name")
        for group in area.groups:
            group.chairs = sorted(roles(group, "chair"), key=extract_last_name)
            group.ad_out_of_area = group.ad_role() and group.ad_role().person not in [role.person for role in area.ads_and_pre_ads]
            # get the url for mailing list subscription
            if group.list_subscribe.startswith('http'):
                group.list_subscribe_url = group.list_subscribe
            elif group.list_email.endswith('@ietf.org'):
                group.list_subscribe_url = MAILING_LIST_INFO_URL % {'list_addr':group.list_email.split('@')[0]}
            else:
                group.list_subscribe_url = "mailto:"+group.list_subscribe

    return render(request, 'group/active_wgs.html', { 'areas':areas })

def active_rgs(request):
    irtf = Group.objects.get(acronym="irtf")
    irtf.chair = roles(irtf, "chair").first()

    groups = Group.objects.filter(type="rg", state="active").order_by("acronym")
    for group in groups:
        group.chairs = sorted(roles(group, "chair"), key=extract_last_name)

    return render(request, 'group/active_rgs.html', { 'irtf': irtf, 'groups': groups })
    
def active_ags(request):

    groups = Group.objects.filter(type="ag", state="active").order_by("acronym")
    for group in groups:
        group.chairs = sorted(roles(group, "chair"), key=extract_last_name)

    return render(request, 'group/active_ags.html', { 'groups': groups })

def active_rags(request):

    groups = Group.objects.filter(type="rag", state="active").order_by("acronym")
    for group in groups:
        group.chairs = sorted(roles(group, "chair"), key=extract_last_name)

    return render(request, 'group/active_rags.html', { 'groups': groups })
    
def bofs(request, group_type):
    groups = Group.objects.filter(type=group_type, state="bof")
    return render(request, 'group/bofs.html',dict(groups=groups))

def chartering_groups(request):
    charter_states = State.objects.filter(used=True, type="charter").exclude(slug__in=("approved", "notrev"))

    group_type_slugs = [ f.type.slug for f in GroupFeatures.objects.filter(has_chartering_process=True) ]
    group_types = GroupTypeName.objects.filter(slug__in=group_type_slugs)

    for t in group_types:
        t.chartering_groups = Group.objects.filter(type=t, charter__states__in=charter_states,state_id__in=('active','bof','proposed','dormant')).select_related("state", "charter").order_by("acronym")
        t.can_manage = can_manage_group_type(request.user, None, t.slug)

        for g in t.chartering_groups:
            g.chartering_type = get_chartering_type(g.charter)
            g.charter.ballot = g.charter.active_ballot()

    return render(request, 'group/chartering_groups.html',
                  dict(charter_states=charter_states,
                       group_types=group_types))

def concluded_groups(request):
    sections = OrderedDict()

    sections['WGs'] = Group.objects.filter(type='wg', state="conclude").select_related("state", "charter").order_by("parent__name","acronym")
    sections['RGs'] = Group.objects.filter(type='rg', state="conclude").select_related("state", "charter").order_by("parent__name","acronym")
    sections['BOFs'] = Group.objects.filter(type='wg', state="bof-conc").select_related("state", "charter").order_by("parent__name","acronym")
    sections['AGs'] = Group.objects.filter(type='ag', state="conclude").select_related("state", "charter").order_by("parent__name","acronym")
    sections['RAGs'] = Group.objects.filter(type='rag', state="conclude").select_related("state", "charter").order_by("parent__name","acronym")
    sections['Directorates'] = Group.objects.filter(type='dir', state="conclude").select_related("state", "charter").order_by("parent__name","acronym")
    sections['Review teams'] = Group.objects.filter(type='review', state="conclude").select_related("state", "charter").order_by("parent__name","acronym")
    sections['Teams'] = Group.objects.filter(type='team', state="conclude").select_related("state", "charter").order_by("parent__name","acronym")
    sections['Programs'] = Group.objects.filter(type='program', state="conclude").select_related("state", "charter").order_by("parent__name","acronym")

    for name, groups in sections.items():
        
        # add start/conclusion date
        d = dict((g.pk, g) for g in groups)

        for g in groups:
            g.start_date = g.conclude_date = None

        for e in ChangeStateGroupEvent.objects.filter(group__in=groups, state="active").order_by("-time"):
            d[e.group_id].start_date = e.time

        for e in ChangeStateGroupEvent.objects.filter(group__in=groups, state="conclude").order_by("time"):
            d[e.group_id].conclude_date = e.time

    return render(request, 'group/concluded_groups.html',
                  dict(sections=sections))

def prepare_group_documents(request, group, clist):
    found_docs, meta = prepare_document_table(request, docs_tracked_by_community_list(clist), request.GET, max_results=500)

    docs = []
    docs_related = []

    # split results
    for d in found_docs:
        # non-WG drafts and call for WG adoption are considered related
        if (d.group != group
            or (d.stream_id and d.get_state_slug("draft-stream-%s" % d.stream_id) in ("c-adopt", "wg-cand"))):
            d.search_heading = "Related Internet-Draft"
            docs_related.append(d)
        else:
            docs.append(d)

    meta_related = meta.copy()

    return docs, meta, docs_related, meta_related

def group_home(request, acronym, group_type=None):
    group = get_group_or_404(acronym, group_type)
    kwargs = dict(acronym=group.acronym)
    if group_type:
        kwargs["group_type"] = group_type
    return HttpResponseRedirect(urlreverse(group.features.default_tab, kwargs=kwargs))

def group_documents(request, acronym, group_type=None):
    group = get_group_or_404(acronym, group_type)
    if not group.features.has_documents:
        raise Http404

    if not group.communitylist_set.exists():
        setup_default_community_list_for_group(group)
    clist = group.communitylist_set.first()

    docs, meta, docs_related, meta_related = prepare_group_documents(request, group, clist)

    subscribed = request.user.is_authenticated and EmailSubscription.objects.filter(community_list=clist, email__person__user=request.user)

    context = construct_group_menu_context(request, group, "documents", group_type, {
                'docs': docs,
                'meta': meta,
                'docs_related': docs_related,
                'meta_related': meta_related,
                'subscribed': subscribed,
                'clist': clist,
                })

    return render(request, 'group/group_documents.html', context)

def group_documents_txt(request, acronym, group_type=None):
    """Return tabulator-separated rows with documents for group."""
    group = get_group_or_404(acronym, group_type)
    if not group.features.has_documents:
        raise Http404

    clist = get_object_or_404(CommunityList, group=group)

    docs, meta, docs_related, meta_related = prepare_group_documents(request, group, clist)

    for d in docs:
        d.prefix = d.get_state().name

    for d in docs_related:
        d.prefix = "Related %s" % d.get_state().name

    rows = []
    for d in itertools.chain(docs, docs_related):
        rfc_number = d.rfc_number()
        if rfc_number != None:
            name = rfc_number
        else:
            name = "%s-%s" % (d.name, d.rev)

        rows.append("\t".join((d.prefix, name, clean_whitespace(d.title))))

    return HttpResponse("\n".join(rows), content_type='text/plain; charset=UTF-8')

def group_about(request, acronym, group_type=None):
    group = get_group_or_404(acronym, group_type)

    fill_in_charter_info(group)

    e = group.latest_event(type__in=("changed_state", "requested_close",))
    requested_close = group.state_id != "conclude" and e and e.type == "requested_close"

    e = None
    if group.state_id == "conclude":
        e = group.latest_event(type='closing_note')

    can_manage = can_manage_group_type(request.user, group)
    charter_submit_url = "" 
    if group.features.has_chartering_process: 
        charter_submit_url = urlreverse('ietf.doc.views_charter.submit', kwargs={ "name": charter_name_for_group(group) }) 

    can_provide_update = can_provide_status_update(request.user, group)
    status_update = group.latest_event(type="status_update")


    return render(request, 'group/group_about.html',
                  construct_group_menu_context(request, group, "about", group_type, {
                      "milestones_in_review": group.groupmilestone_set.filter(state="review"),
                      "milestone_reviewer": milestone_reviewer_for_group_type(group_type),
                      "requested_close": requested_close,
                      "can_manage": can_manage,
                      "can_provide_status_update": can_provide_update,
                      "status_update": status_update,
                      "charter_submit_url": charter_submit_url,
                      "editable_roles": group.used_roles or group.features.default_used_roles,
                      "closing_note": e,
                  }))

def all_status(request):
    wgs = Group.objects.filter(type='wg',state__in=['active','bof'])
    rgs = Group.objects.filter(type='rg',state__in=['active','proposed'])

    wg_reports = []
    for wg in wgs:
        e = wg.latest_event(type='status_update')
        if e:
            wg_reports.append(e)

    wg_reports.sort(key=lambda x: (x.group.parent.acronym,timezone.now()-x.time))

    rg_reports = []
    for rg in rgs:
        e = rg.latest_event(type='status_update')
        if e:
            rg_reports.append(e)

    return render(request, 'group/all_status.html',
                  { 'wg_reports': wg_reports,
                    'rg_reports': rg_reports,
                  }
                 )

def group_about_status(request, acronym, group_type=None):
    group = get_group_or_404(acronym, group_type)
    status_update = group.latest_event(type='status_update')
    can_provide_update = can_provide_status_update(request.user, group)
    return render(request, 'group/group_about_status.html',
                  { 'group' : group,
                    'status_update': status_update,
                    'can_provide_status_update': can_provide_update,
                  }
                 )

def group_about_status_meeting(request, acronym, num, group_type=None):
    meeting = get_meeting(num)
    group = get_group_or_404(acronym, group_type)
    status_update = group.status_for_meeting(meeting)
    return render(request, 'group/group_about_status_meeting.html',
                  { 'group' : group,
                    'status_update': status_update,
                    'meeting': meeting,
                  }
                 )

def group_about_status_edit(request, acronym, group_type=None):
    group = get_group_or_404(acronym, group_type)
    if not can_provide_status_update(request.user, group):
        raise Http404
    old_update = group.latest_event(type='status_update')

    login = request.user.person

    if request.method == 'POST':
        if 'submit_response' in request.POST:
            form = StatusUpdateForm(request.POST, request.FILES)
            if form.is_valid():
                from_file = form.cleaned_data['txt']
                if from_file:
                    update_text = from_file
                else:
                    update_text = form.cleaned_data['content']
                group.groupevent_set.create(
                    by=login,
                    type='status_update',
                    desc=update_text,
                ) 
                return redirect('ietf.group.views.group_about',acronym=group.acronym)
        else:
            form = None
    else:
        form = None

    if not form:
        form = StatusUpdateForm(initial={"content": old_update.desc if old_update else ""})

    return render(request, 'group/group_about_status_edit.html',
                  { 
                    'form': form,
                    'group':group,
                  }
                 )

def get_group_email_aliases(acronym, group_type):
    if acronym:
        pattern = re.compile(r'expand-(%s)(-\w+)@.*? +(.*)$'%acronym)
    else:
        pattern = re.compile(r'expand-(.*?)(-\w+)@.*? +(.*)$')

    aliases = []
    with io.open(settings.GROUP_VIRTUAL_PATH,"r") as virtual_file:
        for line in virtual_file.readlines():
            m = pattern.match(line)
            if m:
                if acronym or not group_type or Group.objects.filter(acronym=m.group(1),type__slug=group_type):
                    aliases.append({'acronym':m.group(1),'alias_type':m.group(2),'expansion':m.group(3)})
    return aliases

def email(request, acronym, group_type=None):
    group = get_group_or_404(acronym, group_type)

    aliases = get_group_email_aliases(acronym, group_type)
    expansions = gather_relevant_expansions(group=group)

    return render(request, 'group/email.html',
                  construct_group_menu_context(request, group, "email expansions", group_type, {
                       'expansions':expansions,
                       'aliases':aliases,
                       'group':group,
                       'ietf_domain':settings.IETF_DOMAIN,
                  })) 

def history(request, acronym, group_type=None):
    group = get_group_or_404(acronym, group_type)

    events = group.groupevent_set.all().select_related('by').order_by('-time', '-id')
    can_add_comment = is_authorized_in_group(request.user,group)

    return render(request, 'group/history.html',
                  construct_group_menu_context(request, group, "history", group_type, {
                      "group": group,
                      "events": events,
                      "can_add_comment": can_add_comment,
                  }))

def materials(request, acronym, group_type=None):
    group = get_group_or_404(acronym, group_type)
    if not group.features.has_nonsession_materials:
        raise Http404

    docs = get_group_materials(group).order_by("type__order", "-time").select_related("type")
    doc_types = OrderedDict()
    for d in docs:
        if d.type not in doc_types:
            doc_types[d.type] = []
        doc_types[d.type].append(d)

    return render(request, 'group/materials.html',
                  construct_group_menu_context(request, group, "materials", group_type, {
                      "doc_types": list(doc_types.items()),
                      "can_manage_materials": can_manage_materials(request.user, group)
                  }))

@cache_page(60 * 60)
def dependencies(request, acronym, group_type=None, output_type="pdf"):
    group = get_group_or_404(acronym, group_type)
    if not group.features.has_documents or output_type not in ["dot", "pdf", "svg"]:
        raise Http404

    dothandle, dotname = mkstemp()
    os.close(dothandle)
    dotfile = io.open(dotname, "w")
    dotfile.write(make_dot(group))
    dotfile.close()

    if (output_type == "dot"):
        return HttpResponse(make_dot(group),
                            content_type='text/plain; charset=UTF-8'
                            )

    unflathandle, unflatname = mkstemp()
    os.close(unflathandle)
    outhandle, outname = mkstemp()
    os.close(outhandle)

    pipe("%s -f -l 10 -o %s %s" % (settings.UNFLATTEN_BINARY, unflatname, dotname))
    pipe("%s -T%s -o %s %s" % (settings.DOT_BINARY, output_type, outname, unflatname))

    outhandle = io.open(outname, "rb")
    out = outhandle.read()
    outhandle.close()

    os.unlink(outname)
    os.unlink(unflatname)
    os.unlink(dotname)

    if (output_type == "pdf"):
        output_type = "application/pdf"
    elif (output_type == "svg"):
        output_type = "image/svg+xml"
    return HttpResponse(out, content_type=output_type)

def email_aliases(request, acronym=None, group_type=None):
    group = get_group_or_404(acronym,group_type) if acronym else None

    if not acronym:
        # require login for the overview page, but not for the group-specific
        # pages 
        if not request.user.is_authenticated:
                return redirect('%s?next=%s' % (settings.LOGIN_URL, request.path))

    aliases = get_group_email_aliases(acronym, group_type)

    return render(request,'group/email_aliases.html',{'aliases':aliases,'ietf_domain':settings.IETF_DOMAIN,'group':group})

def meetings(request, acronym=None, group_type=None):
    group = get_group_or_404(acronym,group_type) if acronym else None

    four_years_ago = timezone.now()-datetime.timedelta(days=4*365)

    sessions = add_event_info_to_session_qs(
        group.session_set.filter(
            meeting__date__gt=four_years_ago,
            type__in=['regular','plenary','other']
        )
    ).filter(
        current_status__in=['sched','schedw','appr','canceled'],
    )

    future, in_progress, recent, past = group_sessions(sessions)

    can_edit = group.has_role(request.user,group.features.groupman_roles)
    can_always_edit = has_role(request.user,["Secretariat","Area Director"])

    return render(request,'group/meetings.html',
                  construct_group_menu_context(request, group, "meetings", group_type, {
                     'group':group,
                     'future':future,
                     'in_progress':in_progress,
                     'recent':recent,
                     'past':past,
                     'can_edit':can_edit,
                     'can_always_edit':can_always_edit,
                  }))

def chair_photos(request, group_type=None):
    roles = sorted(Role.objects.filter(group__type=group_type, group__state='active', name_id='chair'),key=lambda x: x.person.last_name()+x.person.name+x.group.acronym)
    for role in roles:
        role.last_initial = role.person.last_name()[0]
    return render(request, 'group/all_photos.html', {'group_type': group_type, 'role': 'Chair', 'roles': roles })

def reorder_roles(roles, role_names):
    list = []
    for name in role_names:
        list += [ r for r in roles if r.name_id == name ]
    list += [ r for r in roles if not r in list ]
    return list
    
def group_photos(request, group_type=None, acronym=None):
    group = get_object_or_404(Group, acronym=acronym)
    roles = sorted(Role.objects.filter(group__acronym=acronym),key=lambda x: x.name.name+x.person.last_name())

    roles = reorder_roles(roles, group.features.role_order)
    for role in roles:
        role.last_initial = role.person.last_name()[0]
    return render(request, 'group/group_photos.html',
                  construct_group_menu_context(request, group, "photos", group_type, {
                      'group_type': group_type,
                      'roles': roles,
                      'group':group }))



## XXX Remove after testing
# def get_or_create_initial_charter(group, group_type):
#     charter_name = charter_name_for_group(group)
# 
#     try:
#         charter = Document.objects.get(docalias__name=charter_name)
#     except Document.DoesNotExist:
#         charter = Document(
#             name=charter_name,
#             type_id="charter",
#             title=group.name,
#             group=group,
#             abstract=group.name,
#             rev="00-00",
#         )
#         charter.save()
#         charter.set_state(State.objects.get(used=True, type="charter", slug="notrev"))
# 
#         # Create an alias as well
#         DocAlias.objects.create(name=charter.name).docs.add(charter)
# 
#     return charter
# 
# @login_required
# def submit_initial_charter(request, group_type=None, acronym=None):
# 
#     # This needs refactoring.
#     # The signature assumed you could have groups with the same name, but with different types, which we do not allow.
#     # Consequently, this can be called with an existing group acronym and a type 
#     # that doesn't match the existing group type. The code below essentially ignores the group_type argument.
#     #
#     # If possible, the use of get_or_create_initial_charter should be moved
#     # directly into charter_submit, and this function should go away.
# 
#     if acronym==None:
#         raise Http404
# 
#     group = get_object_or_404(Group, acronym=acronym)
#     if not group.features.has_chartering_process:
#         raise Http404
# 
#     # This is where we start ignoring the passed in group_type
#     group_type = group.type_id
# 
#     if not can_manage_group(request.user, group):
#         permission_denied(request, "You don't have permission to access this view")
# 
#     if not group.charter:
#         group.charter = get_or_create_initial_charter(group, group_type)
#         group.save()
# 
#     return redirect('ietf.doc.views_charter.submit', name=group.charter.name, option="initcharter")

@login_required
def edit(request, group_type=None, acronym=None, action="edit", field=None):
    """Edit or create a group, notifying parties as
    necessary and logging changes as group events."""
    def desc(attr, new, old):
        entry = "%(attr)s changed to <b>%(new)s</b> from %(old)s"
        if new_group:
            entry = "%(attr)s changed to <b>%(new)s</b>"

        return entry % dict(attr=attr, new=new, old=old)

    def format_resources(resources, fs="\n"):
        res = []
        for r in resources:
            if r.display_name:
                res.append("%s %s (%s)" % (r.name.slug, r.value, r.display_name.strip('()')))
            else:
                res.append("%s %s" % (r.name.slug, r.value)) 
                # TODO: This is likely problematic if value has spaces. How then to delineate value and display_name? Perhaps in the short term move to comma or pipe separation.
                # Might be better to shift to a formset instead of parsing these lines.
        return fs.join(res)

    def diff(attr, name):
        if field and attr != field:
            return
        v = getattr(group, attr)
        if clean[attr] != v:
            changes.append((attr, clean[attr], desc(name, clean[attr], v)))
            setattr(group, attr, clean[attr])

    if action == "edit":
        new_group = False
    elif action in ("create","charter"):
        group = None
        new_group = True
    else:
        raise Http404

    if not new_group:
        group = get_group_or_404(acronym, group_type)
        if not group_type and group:
            group_type = group.type_id
        if not (can_manage_group(request.user, group)
                or group.has_role(request.user, group.features.groupman_roles)):
            permission_denied(request, "You don't have permission to access this view")

    if request.method == 'POST':
        form = GroupForm(request.POST, group=group, group_type=group_type, field=field)
        if form.is_valid():
            clean = form.cleaned_data
            if new_group:
                try:
                    group = Group.objects.get(acronym=clean["acronym"])
                    save_group_in_history(group)
                    group.time = timezone.now()
                    group.save()
                except Group.DoesNotExist:
                    group = Group.objects.create(name=clean["name"],
                                              acronym=clean["acronym"],
                                              type=GroupTypeName.objects.get(slug=group_type),
                                              state=clean["state"]
                                              )

                    if group.features.has_documents:
                        setup_default_community_list_for_group(group)

                e = ChangeStateGroupEvent(group=group, type="changed_state")
                e.time = group.time
                e.by = request.user.person
                e.state_id = clean["state"].slug
                e.desc = "Group created in state %s" % clean["state"].name
                e.save()
            else:
                save_group_in_history(group)

            changes = []

            # update the attributes, keeping track of what we're doing
            diff('name', "Name")
            diff('acronym', "Acronym")
            diff('state', "State")
            diff('parent', "IETF Area" if group.type=="wg" else "Group parent")
            diff('list_email', "Mailing list email")
            diff('list_subscribe', "Mailing list subscribe address")
            diff('list_archive', "Mailing list archive")

            personnel_change_text=""
            changed_personnel = set()
            # update roles
            for attr, f in form.fields.items():
                if not (attr.endswith("_roles") or attr == "ad"):
                    continue

                slug = attr
                slug = strip_suffix(slug, "_roles")

                title = f.label

                new = clean[attr]
                if attr == 'ad':
                    new = [ new.role_email('ad') ] if new else []
                old = Email.objects.filter(role__group=group, role__name=slug).select_related("person")
                if set(new) != set(old):
                    changes.append((attr, new, desc(title,
                                        ", ".join(sorted(x.get_name() for x in new)),
                                        ", ".join(sorted(x.get_name() for x in old)))))
                    group.role_set.filter(name=slug).delete()
                    for e in new:
                        Role.objects.get_or_create(name_id=slug, email=e, group=group, person=e.person)
                        if not e.origin or (e.person.user and e.origin == e.person.user.username):
                            e.origin = "role: %s %s" % (group.acronym, slug)
                            e.save()

                    added = set(new) - set(old)
                    deleted = set(old) - set(new)
                    if added:
                        change_text=title + ' added: ' + ", ".join(x.name_and_email() for x in added)
                        personnel_change_text+=change_text+"\n"
                    if deleted:
                        change_text=title + ' deleted: ' + ", ".join(x.name_and_email() for x in deleted)
                        personnel_change_text+=change_text+"\n"
                        
                        today = timezone.now().date()
                        for deleted_email in deleted:
                            active_assignments = ReviewAssignment.objects.filter(
                                reviewer__person=deleted_email.person,
                                state_id__in=['accepted', 'assigned'],
                            )
                            for assignment in active_assignments:
                                if assignment.review_request.deadline > today:
                                    assignment.state_id = 'rejected'
                                else:
                                    assignment.state_id = 'no-response'
                                # save() will update review_request state to 'requested'
                                # if needed, so that the review can be assigned to someone else
                                assignment.save()
                                
                    changed_personnel.update(set(old)^set(new))

            if personnel_change_text!="":
                changed_personnel = [ str(p) for p in changed_personnel ]
                personnel_change_text = "%s has updated %s personnel:\n\n" % (request.user.person.plain_name(), group.acronym.upper() ) + personnel_change_text
                email_personnel_change(request, group, personnel_change_text, changed_personnel)

            if 'resources' in clean:
                old_resources = sorted(format_resources(group.groupextresource_set.all()).splitlines())
                new_resources = sorted(clean['resources'])
                if old_resources != new_resources:
                    group.groupextresource_set.all().delete()
                    for u in new_resources:
                        parts = u.split(None, 2)
                        name = parts[0]
                        value = parts[1]
                        display_name = ' '.join(parts[2:]).strip('()')
                        group.groupextresource_set.create(value=value, name_id=name, display_name=display_name)
                    changes.append(('resources', new_resources, desc('Resources', ", ".join(new_resources), ", ".join(old_resources))))

            group.time = timezone.now()

            if changes and not new_group:
                for attr, new, desc in changes:
                    if attr == 'state':
                        ChangeStateGroupEvent.objects.create(group=group, time=group.time, state=new, by=request.user.person, type="changed_state", desc=desc)
                        if new.slug == 'replaced':
                            replace_charter_of_replaced_group(group=group, by=request.user.person)
                    else:
                        GroupEvent.objects.create(group=group, time=group.time, by=request.user.person, type="info_changed", desc=desc)

            group.save()

            #Handle changes to Closing Note, if any. It's an event, not a group attribute like the others
            closing_note = ""
            e = group.latest_event(type='closing_note')
            if e:
                closing_note = e.desc

            if closing_note != clean.get("closing_note", ""):
                closing_note = clean.get("closing_note", "")
                e = GroupEvent(group=group, by=request.user.person)
                e.type = "closing_note"
                if closing_note == "":
                    e.desc = "(Closing note deleted)" #Flag value so something shows up in history
                else:
                    e.desc = closing_note
                e.save()
 
            if action=="charter":
                return redirect('ietf.doc.views_charter.submit', name=charter_name_for_group(group), option="initcharter")

            return HttpResponseRedirect(group.about_url())
    else: # Not POST:
        if not new_group:
            ad_role = group.ad_role()
            closing_note = ""
            e = group.latest_event(type='closing_note')
            if e:
                closing_note = e.desc
                if closing_note == "(Closing note deleted)":
                    closing_note = ""

            init = dict(name=group.name,
                        acronym=group.acronym,
                        state=group.state,
                        ad=ad_role and ad_role.person and ad_role.person.id,
                        parent=group.parent.id if group.parent else None,
                        list_email=group.list_email if group.list_email else None,
                        list_subscribe=group.list_subscribe if group.list_subscribe else None,
                        list_archive=group.list_archive if group.list_archive else None,
                        resources=format_resources(group.groupextresource_set.all()),
                        closing_note = closing_note,
                        )

        else:
            init = dict(ad=request.user.person.id if group_type == "wg" and has_role(request.user, "Area Director") else None,
                        )
        form = GroupForm(initial=init, group=group, group_type=group_type, field=field)

    return render(request, 'group/edit.html',
                  dict(group=group,
                       form=form,
                       action=action))

@login_required
def conclude(request, acronym, group_type=None):
    """Request the closing of group, prompting for instructions."""
    group = get_group_or_404(acronym, group_type)

    if not can_manage_group_type(request.user, group):
        permission_denied(request, "You don't have permission to access this view")

    if request.method == 'POST':
        form = ConcludeGroupForm(request.POST)
        if form.is_valid():
            instructions = form.cleaned_data['instructions']
            closing_note = form.cleaned_data['closing_note']

            if closing_note != "":
                instructions = instructions+"\n\n=====\nClosing note:\n\n"+closing_note
            email_admin_re_charter(request, group, "Request closing of group", instructions, 'group_closure_requested')

            e = GroupEvent(group=group, by=request.user.person)
            e.type = "requested_close"
            e.desc = "Requested closing group"
            e.save()

            if closing_note != "":
                e = GroupEvent(group=group, by=request.user.person)
                e.type = "closing_note"
                e.desc = closing_note
                e.save()

            kwargs = {'acronym':group.acronym}
            if group_type:
                kwargs['group_type'] = group_type
   
            return redirect(group.features.about_page, **kwargs)
    else:
        form = ConcludeGroupForm()

    return render(request, 'group/conclude.html', {
        'form': form,
        'group': group,
        'group_type': group_type,
    })

@login_required
def customize_workflow(request, group_type=None, acronym=None):
    group = get_group_or_404(acronym, group_type)
    if not group_type:
        group_type = group.type_id
    if not group.features.customize_workflow:
        raise Http404

    if not (can_manage_group(request.user, group)
            or group.has_role(request.user, group.features.groupman_roles)):
        permission_denied(request, "You don't have permission to access this view")

    if group_type == "rg":
        stream_id = "irtf"
        MANDATORY_STATES = ('candidat', 'active', 'rfc-edit', 'pub', 'dead')
    else:
        stream_id = "ietf"
        MANDATORY_STATES = ('c-adopt', 'wg-doc', 'sub-pub')

    if request.method == 'POST':
        action = request.POST.get("action")
        if action == "setstateactive":
            active = request.POST.get("active") == "1"
            try:
                state = State.objects.exclude(slug__in=MANDATORY_STATES).get(pk=request.POST.get("state"))
            except State.DoesNotExist:
                return HttpResponse("Invalid state %s" % request.POST.get("state"))

            if active:
                group.unused_states.remove(state)
            else:
                group.unused_states.add(state)

            # redirect so the back button works correctly, otherwise
            # repeated POSTs fills up the history
            return redirect("ietf.group.views.customize_workflow", group_type=group.type_id, acronym=group.acronym)

        if action == "setnextstates":
            try:
                state = State.objects.get(pk=request.POST.get("state"))
            except State.DoesNotExist:
                return HttpResponse("Invalid state %s" % request.POST.get("state"))

            next_states = State.objects.filter(used=True, type='draft-stream-%s' % stream_id, pk__in=request.POST.getlist("next_states"))
            unused = group.unused_states.all()
            if set(next_states.exclude(pk__in=unused)) == set(state.next_states.exclude(pk__in=unused)):
                # just use the default
                group.groupstatetransitions_set.filter(state=state).delete()
            else:
                transitions, _ = GroupStateTransitions.objects.get_or_create(group=group, state=state)
                transitions.next_states.clear()
                transitions.next_states.set(next_states)

            return redirect("ietf.group.views.customize_workflow", group_type=group.type_id, acronym=group.acronym)

        if action == "settagactive":
            active = request.POST.get("active") == "1"
            try:
                tag = DocTagName.objects.get(pk=request.POST.get("tag"))
            except DocTagName.DoesNotExist:
                return HttpResponse("Invalid tag %s" % request.POST.get("tag"))

            if active:
                group.unused_tags.remove(tag)
            else:
                group.unused_tags.add(tag)

            return redirect("ietf.group.views.customize_workflow", group_type=group.type_id, acronym=group.acronym)

    # put some info for the template on tags and states
    unused_tags = group.unused_tags.all().values_list('slug', flat=True)
    tags = DocTagName.objects.filter(slug__in=get_tags_for_stream_id(stream_id))
    for t in tags:
        t.used = t.slug not in unused_tags

    unused_states = group.unused_states.all().values_list('slug', flat=True)
    states = State.objects.filter(used=True, type="draft-stream-%s" % stream_id)
    transitions = dict((o.state, o) for o in group.groupstatetransitions_set.all())
    for s in states:
        s.used = s.slug not in unused_states
        s.mandatory = s.slug in MANDATORY_STATES

        default_n = s.next_states.all()
        if s in transitions:
            n = transitions[s].next_states.all()
        else:
            n = default_n

        s.next_states_checkboxes = [(x in n, x in default_n, x) for x in states]
        s.used_next_states = [x for x in n if x.slug not in unused_states]

    return render(request, 'group/customize_workflow.html', {
            'group': group,
            'states': states,
            'tags': tags,
            })


def streams(request):
    streams = [ s.slug for s in StreamName.objects.all().exclude(slug__in=['ietf', 'legacy']) ]
    streams = Group.objects.filter(acronym__in=streams)
    return render(request, 'group/index.html', {'streams':streams})

def stream_documents(request, acronym):
    streams = [ s.slug for s in StreamName.objects.all().exclude(slug__in=['ietf', 'legacy']) ]
    if not acronym in streams:
        raise Http404("No such stream: %s" % acronym)
    group = get_object_or_404(Group, acronym=acronym)
    editable = has_role(request.user, "Secretariat") or group.has_role(request.user, "chair")
    stream = StreamName.objects.get(slug=acronym)

    qs = Document.objects.filter(states__type="draft", states__slug__in=["active", "rfc"], stream=acronym)
    docs, meta = prepare_document_table(request, qs, max_results=1000)
    return render(request, 'group/stream_documents.html', {'stream':stream, 'docs':docs, 'meta':meta, 'editable':editable } )


def stream_edit(request, acronym):
    group = get_object_or_404(Group, acronym=acronym)

    if not (has_role(request.user, "Secretariat") or group.has_role(request.user, "chair")):
        permission_denied(request, "You don't have permission to access this page.")

    chairs = Email.objects.filter(role__group=group, role__name="chair").select_related("person")

    if request.method == 'POST':
        form = StreamEditForm(request.POST)

        if form.is_valid():
            save_group_in_history(group)

            # update roles
            attr, slug, title = ('delegates', 'delegate', "Delegates")

            new = form.cleaned_data[attr]
            old = Email.objects.filter(role__group=group, role__name=slug).select_related("person")
            if set(new) != set(old):
                desc = "%s changed to <b>%s</b> from %s" % (
                    title, ", ".join(x.get_name() for x in new), ", ".join(x.get_name() for x in old))

                GroupEvent.objects.create(group=group, by=request.user.person, type="info_changed", desc=desc)

                group.role_set.filter(name=slug).delete()
                for e in new:
                    Role.objects.get_or_create(name_id=slug, email=e, group=group, person=e.person)
                    if not e.origin or e.origin == e.person.user.username:
                        e.origin = "role: %s %s" % (group.acronym, slug)
                        e.save()

            return redirect("ietf.group.views.streams")
    else:
        form = StreamEditForm(initial=dict(delegates=Email.objects.filter(role__group=group, role__name="delegate")))

    return render(request, 'group/stream_edit.html',
                    {
                        'group': group,
                        'chairs': chairs,
                        'form': form,
                    },
                )


def group_json(request, acronym):
    group = get_object_or_404(Group, acronym=acronym)

    return HttpResponse(json.dumps(group.json_dict(request.build_absolute_uri('/')),
                                   sort_keys=True, indent=2),
                        content_type="application/json")

@cache_control(public=True, max_age=30*60)
@cache_page(30 * 60)
def group_menu_data(request):
    groups = Group.objects.filter(state="active", type__features__acts_like_wg=True, parent__state="active").order_by("acronym")

    groups_by_parent = defaultdict(list)
    for g in groups:
        url = urlreverse("ietf.group.views.group_home", kwargs={ 'group_type': g.type_id, 'acronym': g.acronym })
        groups_by_parent[g.parent_id].append({ 'acronym': g.acronym, 'name': escape(g.name), 'url': url })

    return JsonResponse(groups_by_parent)


# --- Review views -----------------------------------------------------

def get_open_review_requests_for_team(team, assignment_status=None):
    open_review_requests = ReviewRequest.objects.filter(team=team).filter(
        Q(state_id='requested') | Q(state_id='assigned',reviewassignment__state__in=('assigned','accepted'))
    ).prefetch_related(
        "type", "state", "doc", "doc__states",
    ).order_by("-time", "-id").distinct()

    if assignment_status == "unassigned":
        open_review_requests = suggested_review_requests_for_team(team) + list(open_review_requests.filter(state_id='requested'))
    elif assignment_status == "assigned":
        open_review_requests = list(open_review_requests.filter(state_id='assigned'))
    else:
        open_review_requests = suggested_review_requests_for_team(team) + list(open_review_requests)

    #today = timezone.now().date()
    #unavailable_periods = current_unavailable_periods_for_reviewers(team)
    #for r in open_review_requests:
        #if r.reviewer:
        #    r.reviewer_unavailable = any(p.availability == "unavailable"
        #                                 for p in unavailable_periods.get(r.reviewer.person_id, []))
        #r.due = max(0, (today - r.deadline).days)

    return open_review_requests

def review_requests(request, acronym, group_type=None):
    group = get_group_or_404(acronym, group_type)
    if not group.features.has_reviews:
        raise Http404

    unassigned_review_requests = [r for r in get_open_review_requests_for_team(group) if not r.state_id=='assigned']
    unassigned_review_requests.sort(key=lambda r: r.doc.name)

    open_review_assignments = list(ReviewAssignment.objects.filter(review_request__team=group, state_id__in=('assigned','accepted')).order_by('-assigned_on'))
    today = timezone.now().date()
    unavailable_periods = current_unavailable_periods_for_reviewers(group)
    for a in open_review_assignments:
        a.reviewer_unavailable = any(p.availability == "unavailable"
                                     for p in unavailable_periods.get(a.reviewer.person_id, []))
        a.due = max(0, (today - a.review_request.deadline).days)

    closed_review_assignments = ReviewAssignment.objects.filter(review_request__team=group).exclude(state_id__in=('assigned','accepted')).prefetch_related("state","result").order_by('-assigned_on')

    closed_review_requests = ReviewRequest.objects.filter(team=group).exclude(state__in=("requested", "assigned")).prefetch_related("type", "state", "doc").order_by("-time", "-id")

    since_choices = [
        (None, "1 month"),
        ("3m", "3 months"),
        ("6m", "6 months"),
        ("1y", "1 year"),
        ("2y", "2 years"),
        ("all", "All"),
    ]
    since = request.GET.get("since", None)
    if since not in [key for key, label in since_choices]:
        since = None

    if since != "all":
        date_limit = {
            None: datetime.timedelta(days=31),
            "3m": datetime.timedelta(days=31 * 3),
            "6m": datetime.timedelta(days=180),
            "1y": datetime.timedelta(days=365),
            "2y": datetime.timedelta(days=2 * 365),
        }[since]

        closed_review_requests = closed_review_requests.filter(
              Q(reviewrequestdocevent__type='closed_review_request', reviewrequestdocevent__time__gte=datetime_today_start() - date_limit)
            | Q(reviewrequestdocevent__isnull=True, time__gte=datetime_today_start() - date_limit)
        ).distinct()

        closed_review_assignments = closed_review_assignments.filter(completed_on__gte = datetime_today_start() - date_limit)

    return render(request, 'group/review_requests.html',
                  construct_group_menu_context(request, group, "review requests", group_type, {
                      "unassigned_review_requests": unassigned_review_requests,
                      "open_review_assignments": open_review_assignments,
                      "closed_review_requests": closed_review_requests,
                      "closed_review_assignments": closed_review_assignments,
                      "since_choices": since_choices,
                      "since": since,
                      "can_manage_review_requests": can_manage_review_requests_for_team(request.user, group),
                      "can_access_stats": can_access_review_stats_for_team(request.user, group),
                  }))

def reviewer_overview(request, acronym, group_type=None):
    group = get_group_or_404(acronym, group_type)
    if not group.features.has_reviews:
        raise Http404

    can_manage = can_manage_review_requests_for_team(request.user, group)

    can_reset_next_reviewer = can_manage and group.reviewteamsettings.reviewer_queue_policy_id == 'RotateAlphabetically'

    reviewers = get_reviewer_queue_policy(group).default_reviewer_rotation_list(include_unavailable=True)

    reviewer_settings = { s.person_id: s for s in ReviewerSettings.objects.filter(team=group) }
    unavailable_periods = defaultdict(list)
    for p in unavailable_periods_to_list().filter(team=group):
        unavailable_periods[p.person_id].append(p)
    reviewer_roles = { r.person_id: r for r in Role.objects.filter(group=group, name="reviewer").select_related("email") }

    today = timezone.now().date()

    max_closed_reqs = settings.GROUP_REVIEW_MAX_ITEMS_TO_SHOW_IN_REVIEWER_LIST
    days_back = settings.GROUP_REVIEW_DAYS_TO_SHOW_IN_REVIEWER_LIST
    if can_manage:
        secretary_settings = (ReviewSecretarySettings.objects.filter(person=
                                                                     request.user.person,
                                                                     team=group).first()
                              or ReviewSecretarySettings(person=request.user.person,
                                                         team=group))
        if secretary_settings:
            max_closed_reqs = secretary_settings.max_items_to_show_in_reviewer_list
            days_back = secretary_settings.days_to_show_in_reviewer_list

    if max_closed_reqs == None:
        max_closed_reqs = 10

    if days_back == None:
        days_back = 365
    req_data_for_reviewers = latest_review_assignments_for_reviewers(group, days_back)
    assignment_state_by_slug = { n.slug: n for n in ReviewAssignmentStateName.objects.all() }

    days_needed = days_needed_to_fulfill_min_interval_for_reviewers(group)

    for person in reviewers:
        person.settings = reviewer_settings.get(person.pk) or ReviewerSettings(team=group, person=person)
        person.settings_url = None
        person.role = reviewer_roles.get(person.pk)
        if person.role and (can_manage or user_is_person(request.user, person)):
            kwargs = { "acronym": group.acronym, "reviewer_email": person.role.email.address }
            if group_type:
                kwargs["group_type"] = group_type
            person.settings_url = urlreverse("ietf.group.views.change_reviewer_settings", kwargs=kwargs)
        if can_access_review_stats_for_team(request.user, group):
            person.unavailable_periods = unavailable_periods.get(person.pk, [])
            person.completely_unavailable = any(p.availability == "unavailable"
                                           and (p.start_date is None or p.start_date <= today) and (p.end_date is None or today <= p.end_date)
                                           for p in person.unavailable_periods)
            person.busy = person.id in days_needed 
        

        days_since = 9999
        req_data = req_data_for_reviewers.get(person.pk, [])

        closed_reqs = 0
        latest_reqs = []
        for d in req_data:
            if d.state in ["assigned", "accepted"] or closed_reqs < max_closed_reqs:
                if not d.state in ["assigned", "accepted"]:
                    closed_reqs += 1
                latest_reqs.append((d.assignment_pk, d.request_pk, d.doc_name, d.reviewed_rev, d.assigned_time, d.deadline,
                                    assignment_state_by_slug.get(d.state),
                                    int(math.ceil(d.assignment_to_closure_days)) if d.assignment_to_closure_days is not None else None))
            if d.state in ["completed", "completed_in_time", "completed_late"]:
                if d.assigned_time is not None:
                    delta = timezone.now() - d.assigned_time
                    if d.assignment_to_closure_days is not None:
                        days = int(delta.days - d.assignment_to_closure_days)
                        if days_since > days: days_since = days

        person.latest_reqs = latest_reqs
        person.days_since_completed_review = days_since

    return render(request, 'group/reviewer_overview.html',
                  construct_group_menu_context(request, group, "reviewers", group_type, {
                      "reviewers": reviewers,
                      "can_access_stats": can_access_review_stats_for_team(request.user, group),
                      "can_reset_next_reviewer": can_reset_next_reviewer,
                  }))


@login_required
def manage_review_requests(request, acronym, group_type=None, assignment_status=None):
    group = get_group_or_404(acronym, group_type)
    if not group.features.has_reviews:
        raise Http404

    if not can_manage_review_requests_for_team(request.user, group):
        permission_denied(request, "You do not have permission to perform this action")

    review_requests = get_open_review_requests_for_team(group, assignment_status=assignment_status)

    document_requests = extract_revision_ordered_review_requests_for_documents_and_replaced(
        ReviewRequest.objects.filter(state__in=("part-completed", "completed", "assigned"), team=group).prefetch_related("reviewassignment_set__result"),
        set(r.doc.name for r in review_requests),
    )

    # we need a mutable query dict for resetting upon saving with
    # conflicts
    query_dict = request.POST.copy() if request.method == "POST" else None

    for req in review_requests:
        req.form = ManageReviewRequestForm(req, query_dict)

        # add previous requests
        l = []
        rev = None
        for r in document_requests.get(req.doc.name, []):
            # take all on the latest reviewed rev
            for a in r.reviewassignment_set.all():
                if l and rev:
                    if r.doc_id == l[0].doc_id and a.reviewed_rev:
                        if int(a.reviewed_rev) > int(rev):
                            l = [r]
                        elif int(a.reviewed_rev) == int(rev):
                            l.append(r)
                else:
                    l = [r]
                rev = l[0].reviewassignment_set.first().reviewed_rev

        augment_review_requests_with_events(l)

        req.latest_reqs = l
        req.wg_chairs = None
        if req.doc.group:
            req.wg_chairs = [role.person for role in req.doc.group.role_set.filter(name__slug='chair')]

    saving = False
    newly_closed = newly_opened = newly_assigned = 0

    if request.method == "POST":
        form_action = request.POST.get("action", "")
        saving = form_action.startswith("save")

        # check for conflicts
        review_requests_dict = { str(r.pk): r for r in review_requests if r.pk}
        posted_reqs = set(request.POST.getlist("reviewrequest", []))
        posted_reqs.discard(u'None')
        current_reqs = set(review_requests_dict.keys())

        closed_reqs = posted_reqs - current_reqs
        newly_closed = len(closed_reqs)

        opened_reqs = current_reqs - posted_reqs
        newly_opened = len(opened_reqs)
        for r in opened_reqs:
            review_requests_dict[r].form.add_error(None, "New request.")

        form_results = []
        for req in review_requests:
            form_results.append(req.form.is_valid())

        if saving and all(form_results) and not (newly_closed > 0 or newly_opened > 0 or newly_assigned > 0):

            reqs_to_assign = []
            for review_req in review_requests:
                action = review_req.form.cleaned_data.get("action")
                if action=="close":
                    close_review_request(request, review_req, review_req.form.cleaned_data["close"],
                                         review_req.form.cleaned_data["close_comment"])
                elif action=="assign" and review_req.form.cleaned_data["reviewer"]:
                    if review_req.form.cleaned_data.get("review_type"):
                        review_req.type = review_req.form.cleaned_data.get("review_type")
                    reqs_to_assign.append(review_req)

            assignments_by_person = dict()
            for r in reqs_to_assign:
                person = r.form.cleaned_data["reviewer"].person
                if not person in assignments_by_person:
                    assignments_by_person[person] = []
                assignments_by_person[person].append(r)
            
            # Make sure the any assignments to the person at the head
            # of the rotation queue are processed first so that the queue
            # rotates before any more assignments are processed
            reviewer_policy = get_reviewer_queue_policy(group)
            head_of_rotation = reviewer_policy.default_reviewer_rotation_list_without_skipped()[0]
            while head_of_rotation in assignments_by_person:
                for review_req in assignments_by_person[head_of_rotation]:
                    assign_review_request_to_reviewer(request, review_req, review_req.form.cleaned_data["reviewer"],review_req.form.cleaned_data["add_skip"])
                    reqs_to_assign.remove(review_req)
                del assignments_by_person[head_of_rotation]
                head_of_rotation = reviewer_policy.default_reviewer_rotation_list_without_skipped()[0]

            for review_req in reqs_to_assign:
                assign_review_request_to_reviewer(request, review_req, review_req.form.cleaned_data["reviewer"],review_req.form.cleaned_data["add_skip"])
            
            kwargs = { "acronym": group.acronym }
            if group_type:
                kwargs["group_type"] = group_type

            if form_action == "save-continue":
                if assignment_status:
                    kwargs["assignment_status"] = assignment_status
                
                return redirect(manage_review_requests, **kwargs)
            else:
                import ietf.group.views
                return redirect(ietf.group.views.review_requests, **kwargs)

    other_assignment_status = {
        "unassigned": "assigned",
        "assigned": "unassigned",
    }.get(assignment_status)

    return render(request, 'group/manage_review_requests.html', {
        'group': group,
        'review_requests': review_requests,
        'newly_closed': newly_closed,
        'newly_opened': newly_opened,
        'newly_assigned': newly_assigned,
        'saving': saving,
        'assignment_status': assignment_status,
        'other_assignment_status': other_assignment_status,
    })

@login_required
def email_open_review_assignments(request, acronym, group_type=None):
    group = get_group_or_404(acronym, group_type)
    if not group.features.has_reviews:
        raise Http404

    if not can_manage_review_requests_for_team(request.user, group):
        permission_denied(request, "You do not have permission to perform this action")

    review_assignments = list(ReviewAssignment.objects.filter(
        review_request__team=group,
        state__in=("assigned", "accepted"),
    ).prefetch_related("reviewer", "review_request__type", "state", "review_request__doc").distinct().order_by("reviewer","-review_request__deadline"))

    for r in review_assignments:
        if r.review_request.doc.telechat_date():
            r.section = 'For telechat %s' % r.review_request.doc.telechat_date().isoformat()
            r.section_order='0'+r.section
        elif r.review_request.type_id == 'early':
            r.section = 'Early review requests:'
            r.section_order='2'
        else:
            r.section = 'Last calls:'
            r.section_order='1'
        e = r.review_request.doc.latest_event(LastCallDocEvent, type="sent_last_call")
        r.lastcall_ends = e and e.expires.date().isoformat()
        r.earlier_review = ReviewAssignment.objects.filter(review_request__doc=r.review_request.doc,reviewer__in=r.reviewer.person.email_set.all(),state="completed")
        if r.earlier_review:
            earlier_reviews_formatted = ['-{} {} reviewed'.format(ra.reviewed_rev, ra.review_request.type.slug) for ra in r.earlier_review]
            r.earlier_reviews = '({})'.format(', '.join(earlier_reviews_formatted))

    # If a document is both scheduled for a telechat and a last call review, replicate
    # a copy of the review assignment in the last calls section (#2118)
    def should_be_replicated_in_last_call_section(r):
        return r.section.startswith('For telechat') and r.review_request.type_id != 'early'
    
    for r in filter(should_be_replicated_in_last_call_section, review_assignments):
        r_new = copy.copy(r)
        r_new.section = 'Last calls:'
        r_new.section_order = '1'
        review_assignments.append(r_new)

    review_assignments.sort(key=lambda r: r.section_order + r.reviewer.person.last_name() + 
                                          r.reviewer.person.first_name())

    back_url = request.GET.get("next")
    if not back_url:
        kwargs = { "acronym": group.acronym }
        if group_type:
            kwargs["group_type"] = group_type

        import ietf.group.views
        back_url = urlreverse(ietf.group.views.review_requests, kwargs=kwargs)

    if request.method == "POST" and request.POST.get("action") == "email":
        form = EmailOpenAssignmentsForm(request.POST)
        if form.is_valid():
            send_mail_text(request,
                            to=form.cleaned_data["to"],
                            frm=form.cleaned_data["frm"],
                            subject=form.cleaned_data["subject"],
                            txt=form.cleaned_data["body"],
                            cc=form.cleaned_data["cc"],
                            extra={"Reply-To": form.cleaned_data["reply_to"]}
                        )
            return HttpResponseRedirect(back_url)
    else:
        (to,cc) = gather_address_lists('review_assignments_summarized',group=group)
        reply_to = Recipient.objects.get(slug='group_secretaries').gather(group=group)
        frm = request.user.person.formatted_email()

        templateqs = DBTemplate.objects.filter(path="/group/%s/email/open_assignments.txt" % group.acronym)
        if templateqs.exists():
            template = templateqs.first()
        else:
            template = DBTemplate.objects.get(path="/group/defaults/email/open_assignments.txt")

        partial_msg = render_to_string(template.path, {
            "review_assignments": review_assignments,
            "rotation_list": get_reviewer_queue_policy(group).default_reviewer_rotation_list()[:10],
            "group" : group,
        })
        
        (msg,_,_) = parse_preformatted(partial_msg)

        body = msg.get_payload()
        subject = msg['Subject']

        form = EmailOpenAssignmentsForm(initial={
            "to": ", ".join(to),
            "cc": ", ".join(cc),
            "reply_to": ", ".join(reply_to),
            "frm": frm,
            "subject": subject,
            "body": body,
        })

    return render(request, 'group/email_open_review_assignments.html', {
        'group': group,
        'review_assignments': review_assignments,
        'form': form,
        'back_url': back_url,
    })


@login_required
def change_reviewer_settings(request, acronym, reviewer_email, group_type=None):
    group = get_group_or_404(acronym, group_type)
    if not group.features.has_reviews:
        raise Http404

    reviewer_role = get_object_or_404(Role, name="reviewer", group=group, email=reviewer_email)
    reviewer = reviewer_role.person

    if not (user_is_person(request.user, reviewer)
            or can_manage_review_requests_for_team(request.user, group)):
        permission_denied(request, "You do not have permission to perform this action")

    exclude_fields = []
    if not can_manage_review_requests_for_team(request.user, group):
        exclude_fields.append('skip_next')

    settings = ReviewerSettings.objects.filter(person=reviewer, team=group).first()
    if not settings:
        settings = ReviewerSettings(person=reviewer, team=group)
        settings.filter_re = get_default_filter_re(reviewer)

    back_url = request.GET.get("next")
    if not back_url:
        import ietf.group.views
        kwargs = { "acronym": group.acronym}
        if group_type:
            kwargs["group_type"] = group_type
        back_url = urlreverse(ietf.group.views.reviewer_overview, kwargs=kwargs)

    # settings
    if request.method == "POST" and request.POST.get("action") == "change_settings":
        prev_min_interval = settings.get_min_interval_display()
        prev_skip_next = settings.skip_next
        settings_form = ReviewerSettingsForm(request.POST, instance=settings, exclude_fields=exclude_fields)
        if settings_form.is_valid():
            settings = settings_form.save()
            if settings_form.has_changed():
                update_change_reason(settings, "Updated %s" % ", ".join(settings_form.changed_data) )

            changes = []
            if settings.get_min_interval_display() != prev_min_interval:
                changes.append("Frequency changed to \"{}\" from \"{}\".".format(settings.get_min_interval_display() or "Not specified", prev_min_interval or "Not specified"))
            if settings.skip_next != prev_skip_next:
                changes.append("Skip next assignments changed to {} from {}.".format(settings.skip_next, prev_skip_next))
            if settings.request_assignment_next:
                changes.append("Reviewer has requested to be the next person selected for an "
                               "assignment, as soon as possible, and will be on the top of "
                               "the queue.") 
            if changes:
                email_reviewer_availability_change(request, group, reviewer_role, "\n\n".join(changes), request.user.person)

            return HttpResponseRedirect(back_url)
    else:
        settings_form = ReviewerSettingsForm(instance=settings,exclude_fields=exclude_fields)

    # periods
    unavailable_periods = unavailable_periods_to_list().filter(person=reviewer, team=group)

    if request.method == "POST" and request.POST.get("action") == "add_period":
        period_form = AddUnavailablePeriodForm(request.POST)
        if period_form.is_valid():
            period = period_form.save(commit=False)
            period.team = group
            period.person = reviewer
            period.save()
            update_change_reason(period, "Added unavailability period: {}".format(period))

            today = timezone.now().date()

            in_the_past = period.end_date and period.end_date < today

            if not in_the_past:
                msg = "{} -- {} {}\n                         {}".format(
                    period.start_date.isoformat() if period.start_date else "indefinite",
                    period.end_date.isoformat() if period.end_date else "indefinite",
                    period.get_availability_display(),
                    period.reason,
                )

                if period.availability == "unavailable":
                    # the secretary might need to reassign
                    # assignments, so mention the current ones

                    review_assignments = ReviewAssignment.objects.filter(state__in=["assigned", "accepted"], reviewer=reviewer_role.email, review_request__team=group)
                    msg += "\n\n"

                    if review_assignments:
                        msg += "{} is currently assigned to review:".format(reviewer_role.person)
                        for r in review_assignments:
                            msg += "\n\n"
                            msg += "{} (deadline: {})".format(r.review_request.doc.name, r.review_request.deadline.isoformat())
                    else:
                        msg += "{} does not have any assignments currently.".format(reviewer_role.person)

                email_reviewer_availability_change(request, group, reviewer_role, msg, request.user.person)

            return HttpResponseRedirect(request.get_full_path())
    else:
        period_form = AddUnavailablePeriodForm()

    if request.method == "POST" and request.POST.get("action") == "delete_period":
        period_id = request.POST.get("period_id")
        if period_id is not None:
            for period in unavailable_periods:
                if str(period.pk) == period_id:
                    period.delete()
                    update_change_reason(period, "Removed unavailability period: {}".format(period))

                    today = timezone.now().date()

                    in_the_past = period.end_date and period.end_date < today

                    if not in_the_past:
                        msg = "Removed unavailable period: {} - {} ({})".format(
                            period.start_date.isoformat() if period.start_date else "indefinite",
                            period.end_date.isoformat() if period.end_date else "indefinite",
                            period.get_availability_display(),
                        )

                        email_reviewer_availability_change(request, group, reviewer_role, msg, request.user.person)

            return HttpResponseRedirect(request.get_full_path())

    for p in unavailable_periods:
        if not p.end_date:
            p.end_form = EndUnavailablePeriodForm(p.start_date, request.POST if request.method == "POST" and request.POST.get("action") == "end_period" else None)

    if request.method == "POST" and request.POST.get("action") == "end_period":
        period_id = request.POST.get("period_id")
        for period in unavailable_periods:
            if str(period.pk) == period_id:
                if not period.end_date and period.end_form.is_valid():
                    period.end_date = period.end_form.cleaned_data["end_date"]
                    period.save()
                    update_change_reason(period, "Set end date of unavailability period: {}".format(period))

                    msg = "Set end date of unavailable period: {} - {} ({})".format(
                        period.start_date.isoformat() if period.start_date else "indefinite",
                        period.end_date.isoformat() if period.end_date else "indefinite",
                        period.get_availability_display(),
                    )

                    email_reviewer_availability_change(request, group, reviewer_role, msg, request.user.person)

                    return HttpResponseRedirect(request.get_full_path())


    return render(request, 'group/change_reviewer_settings.html', {
        'group': group,
        'reviewer_email': reviewer_email,
        'back_url': back_url,
        'settings_form': settings_form,
        'period_form': period_form,
        'unavailable_periods': unavailable_periods,
        'unavailable_periods_history': UnavailablePeriod.history.filter(person=reviewer, team=group),
        'reviewersettings': settings,
    })


@login_required
def change_review_secretary_settings(request, acronym, group_type=None):
    group = get_group_or_404(acronym, group_type)
    if not group.features.has_reviews:
        raise Http404
    if not Role.objects.filter(name="secr", group=group, person__user=request.user).exists():
        raise Http404

    person = request.user.person

    settings = (ReviewSecretarySettings.objects.filter(person=person, team=group).first()
                or ReviewSecretarySettings(person=person, team=group))

    import ietf.group.views
    back_url = urlreverse(ietf.group.views.review_requests, kwargs={ "acronym": acronym, "group_type": group.type_id })

    # settings
    if request.method == "POST":
        settings_form = ReviewSecretarySettingsForm(request.POST, instance=settings)
        if settings_form.is_valid():
            settings_form.save()
            return HttpResponseRedirect(back_url)
    else:
        settings_form = ReviewSecretarySettingsForm(instance=settings)

    return render(request, 'group/change_review_secretary_settings.html', {
        'group': group,
        'back_url': back_url,
        'settings_form': settings_form,
    })

class AddCommentForm(forms.Form):
    comment = forms.CharField(required=True, widget=forms.Textarea, strip=False)

def add_comment(request, acronym, group_type=None):
    group = get_group_or_404(acronym, group_type)

    if not is_authorized_in_group(request.user,group):
        permission_denied(request, "You need to a chair, secretary, or delegate of this group to add a comment.")
    
    if request.method == 'POST':
        form = AddCommentForm(request.POST)
        if form.is_valid():
            comment = form.cleaned_data['comment']
            event = GroupEvent.objects.create(group=group,desc=comment,type="added_comment",by=request.user.person)
            email_comment(request,event)
            return redirect('ietf.group.views.history', acronym=group.acronym)
    else:
        form = AddCommentForm()

    return render(request, 'group/add_comment.html', { 'group':group, 'form':form, })

class ResetNextReviewerForm(forms.Form):
    next_reviewer = forms.ChoiceField()

    def __init__(self, *args, **kwargs):
        instance = kwargs.pop('instance')
        super(ResetNextReviewerForm, self).__init__(*args, **kwargs)
        self.fields['next_reviewer'].choices = [ (p.pk, p.plain_name()) for p in get_reviewer_queue_policy(instance.team).default_reviewer_rotation_list(include_unavailable=True)]

@login_required
def reset_next_reviewer(request, acronym, group_type=None):
    group = get_group_or_404(acronym, group_type)
    if not group.features.has_reviews:
        raise Http404
    if group.reviewteamsettings.reviewer_queue_policy_id != 'RotateAlphabetically':
        raise Http404

    if not Role.objects.filter(name="secr", group=group, person__user=request.user).exists() and not has_role(request.user, "Secretariat"):
        permission_denied(request, "You don't have permission to access this view")

    instance = group.nextreviewerinteam_set.first()
    if not instance:
        raise Http404

    if request.method == 'POST':
        form = ResetNextReviewerForm(request.POST,instance=instance)
        if form.is_valid():
            instance.next_reviewer = Person.objects.get(pk=form.cleaned_data['next_reviewer'])
            instance.save()
            return redirect('ietf.group.views.reviewer_overview', acronym = group.acronym )
    else:
        form = ResetNextReviewerForm(instance=instance)

    return render(request, 'group/reset_next_reviewer.html', { 'group':group, 'form': form,})