# Copyright The IETF Trust 2009-2020, All Rights Reserved
# -*- coding: utf-8 -*-
#
# Some parts Copyright (C) 2009-2010 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 re
import datetime

from django import forms
from django.conf import settings
from django.core.cache import cache
from django.urls import reverse as urlreverse
from django.db.models import Q
from django.http import Http404, HttpResponseBadRequest, HttpResponse, HttpResponseRedirect, QueryDict
from django.shortcuts import render
from django.utils.cache import _generate_cache_key # type: ignore


import debug                            # pyflakes:ignore

from ietf.doc.models import ( Document, DocHistory, DocAlias, State,
    LastCallDocEvent, NewRevisionDocEvent, IESG_SUBSTATE_TAGS, IESG_BALLOT_ACTIVE_STATES )
from ietf.doc.fields import select2_id_doc_name_json
from ietf.doc.utils import get_search_cache_key, augment_events_with_revision
from ietf.group.models import Group
from ietf.idindex.index import active_drafts_index_by_group
from ietf.name.models import DocTagName, DocTypeName, StreamName
from ietf.person.models import Person
from ietf.person.utils import get_active_ads
from ietf.utils.draft_search import normalize_draftname
from ietf.doc.utils_search import prepare_document_table


class SearchForm(forms.Form):
    name = forms.CharField(required=False)
    rfcs = forms.BooleanField(required=False, initial=True)
    activedrafts = forms.BooleanField(required=False, initial=True)
    olddrafts = forms.BooleanField(required=False, initial=False)

    by = forms.ChoiceField(choices=[(x,x) for x in ('author','group','area','ad','state','irtfstate','stream')], required=False, initial='group')
    author = forms.CharField(required=False)
    group = forms.CharField(required=False)
    stream = forms.ModelChoiceField(StreamName.objects.all().order_by('name'), empty_label="any stream", required=False)
    area = forms.ModelChoiceField(Group.objects.filter(type="area", state="active").order_by('name'), empty_label="any area", required=False)
    ad = forms.ChoiceField(choices=(), required=False)
    state = forms.ModelChoiceField(State.objects.filter(type="draft-iesg"), empty_label="any state", required=False)
    substate = forms.ChoiceField(choices=(), required=False)
    irtfstate = forms.ModelChoiceField(State.objects.filter(type="draft-stream-irtf"), empty_label="any state", required=False)

    sort = forms.ChoiceField(
        choices= (
            ("document", "Document"), ("-document", "Document (desc.)"),
            ("title", "Title"), ("-title", "Title (desc.)"),
            ("date", "Date"), ("-date", "Date (desc.)"),
            ("status", "Status"), ("-status", "Status (desc.)"),
            ("ipr", "Ipr"), ("ipr", "Ipr (desc.)"),
            ("ad", "AD"), ("-ad", "AD (desc)"), ),
        required=False, widget=forms.HiddenInput)

    doctypes = forms.ModelMultipleChoiceField(queryset=DocTypeName.objects.filter(used=True).exclude(slug='draft').order_by('name'), required=False)

    def __init__(self, *args, **kwargs):
        super(SearchForm, self).__init__(*args, **kwargs)
        responsible = Document.objects.values_list('ad', flat=True).distinct()
        active_ads = get_active_ads()
        inactive_ads = list(((Person.objects.filter(pk__in=responsible) | Person.objects.filter(role__name="pre-ad",
                                                                                              role__group__type="area",
                                                                                              role__group__state="active")).distinct())
                            .exclude(pk__in=[x.pk for x in active_ads]))
        extract_last_name = lambda x: x.name_parts()[3]
        active_ads.sort(key=extract_last_name)
        inactive_ads.sort(key=extract_last_name)

        self.fields['ad'].choices = [('', 'any AD')] + [(ad.pk, ad.plain_name()) for ad in active_ads] + [('', '------------------')] + [(ad.pk, ad.name) for ad in inactive_ads]
        self.fields['substate'].choices = [('', 'any substate'), ('0', 'no substate')] + [(n.slug, n.name) for n in DocTagName.objects.filter(slug__in=IESG_SUBSTATE_TAGS)]

    def clean_name(self):
        value = self.cleaned_data.get('name','')
        return normalize_draftname(value)

    def clean(self):
        q = self.cleaned_data
        # Reset query['by'] if needed
        if 'by' in q:
            for k in ('author', 'group', 'area', 'ad'):
                if q['by'] == k and not q.get(k):
                    q['by'] = None
            if q['by'] == 'state' and not (q.get('state') or q.get('substate')):
                q['by'] = None
            if q['by'] == 'irtfstate' and not (q.get('irtfstate')):
                q['by'] = None
        else:
            q['by'] = None
        # Reset other fields
        for k in ('author','group', 'area', 'ad'):
            if k != q['by']:
                q[k] = ""
        if q['by'] != 'state':
            q['state'] = q['substate'] = None
        if q['by'] != 'irtfstate':
            q['irtfstate'] = None
        return q

def retrieve_search_results(form, all_types=False):
    """Takes a validated SearchForm and return the results."""

    if not form.is_valid():
        raise ValueError("SearchForm doesn't validate: %s" % form.errors)

    query = form.cleaned_data

    if all_types:
        # order by time here to retain the most recent documents in case we
        # find too many and have to chop the results list
        docs = Document.objects.all().order_by('-time')
    else:
        types = []

        if query['activedrafts'] or query['olddrafts'] or query['rfcs']:
            types.append('draft')

        types.extend(query["doctypes"])

        if not types:
            return Document.objects.none()

        docs = Document.objects.filter(type__in=types)

    # name
    if query["name"]:
        docs = docs.filter(Q(docalias__name__icontains=query["name"]) |
                           Q(title__icontains=query["name"])).distinct()

    # rfc/active/old check buttons
    allowed_draft_states = []
    if query["rfcs"]:
        allowed_draft_states.append("rfc")
    if query["activedrafts"]:
        allowed_draft_states.append("active")
    if query["olddrafts"]:
        allowed_draft_states.extend(['repl', 'expired', 'auth-rm', 'ietf-rm'])

    docs = docs.filter(Q(states__slug__in=allowed_draft_states) |
                       ~Q(type__slug='draft')).distinct()

    # radio choices
    by = query["by"]
    if by == "author":
        docs = docs.filter(
            Q(documentauthor__person__alias__name__icontains=query["author"]) |
            Q(documentauthor__person__email__address__icontains=query["author"])
        )
    elif by == "group":
        docs = docs.filter(group__acronym=query["group"])
    elif by == "area":
        docs = docs.filter(Q(group__type="wg", group__parent=query["area"]) |
                           Q(group=query["area"])).distinct()
    elif by == "ad":
        docs = docs.filter(ad=query["ad"])
    elif by == "state":
        if query["state"]:
            docs = docs.filter(states=query["state"])
        if query["substate"]:
            docs = docs.filter(tags=query["substate"])
    elif by == "irtfstate":
        docs = docs.filter(states=query["irtfstate"])
    elif by == "stream":
        docs = docs.filter(stream=query["stream"])

    return docs

def search(request):
    if request.GET:
        # backwards compatibility
        get_params = request.GET.copy()
        if 'activeDrafts' in request.GET:
            get_params['activedrafts'] = request.GET['activeDrafts']
        if 'oldDrafts' in request.GET:
            get_params['olddrafts'] = request.GET['oldDrafts']
        if 'subState' in request.GET:
            get_params['substate'] = request.GET['subState']

        form = SearchForm(get_params)
        if not form.is_valid():
            return HttpResponseBadRequest("form not valid: %s" % form.errors)

        cache_key = get_search_cache_key(get_params)
        results = cache.get(cache_key)
        if not results:
            results = retrieve_search_results(form)
            cache.set(cache_key, results)

        results, meta = prepare_document_table(request, results, get_params)
        meta['searching'] = True
    else:
        form = SearchForm()
        results = []
        meta = { 'by': None, 'searching': False }
        get_params = QueryDict('')

    return render(request, 'doc/search/search.html', {
        'form':form, 'docs':results, 'meta':meta, 'queryargs':get_params.urlencode() },
    )

def frontpage(request):
    form = SearchForm()
    return render(request, 'doc/frontpage.html', {'form':form})

def search_for_name(request, name):
    def find_unique(n):
        exact = DocAlias.objects.filter(name=n).first()
        if exact:
            return exact.name

        aliases = DocAlias.objects.filter(name__startswith=n)[:2]
        if len(aliases) == 1:
            return aliases[0].name

        aliases = DocAlias.objects.filter(name__contains=n)[:2]
        if len(aliases) == 1:
            return aliases[0].name

        return None

    def cached_redirect(cache_key, url):
        cache.set(cache_key, url, settings.CACHE_MIDDLEWARE_SECONDS)
        return HttpResponseRedirect(url)

    n = name

    cache_key = _generate_cache_key(request, 'GET', [], settings.CACHE_MIDDLEWARE_KEY_PREFIX)
    if cache_key:
        url = cache.get(cache_key, None)
        if url:
            return HttpResponseRedirect(url)

    # chop away extension
    extension_split = re.search(r"^(.+)\.(txt|ps|pdf)$", n)
    if extension_split:
        n = extension_split.group(1)

    redirect_to = find_unique(name)
    if redirect_to:
        return cached_redirect(cache_key, urlreverse("ietf.doc.views_doc.document_main", kwargs={ "name": redirect_to }))
    else:
        # check for embedded rev - this may be ambigious, so don't
        # chop it off if we don't find a match
        rev_split = re.search("^(.+)-([0-9]{2})$", n)
        if rev_split:
            redirect_to = find_unique(rev_split.group(1))
            if redirect_to:
                rev = rev_split.group(2)
                # check if we can redirect directly to the rev
                if DocHistory.objects.filter(doc__docalias__name=redirect_to, rev=rev).exists():
                    return cached_redirect(cache_key, urlreverse("ietf.doc.views_doc.document_main", kwargs={ "name": redirect_to, "rev": rev }))
                else:
                    return cached_redirect(cache_key, urlreverse("ietf.doc.views_doc.document_main", kwargs={ "name": redirect_to }))

    # build appropriate flags based on string prefix
    doctypenames = DocTypeName.objects.filter(used=True)
    # This would have been more straightforward if document prefixes couldn't
    # contain a dash.  Probably, document prefixes shouldn't contain a dash ...
    search_args = "?name=%s" % n
    if   n.startswith("draft"):
        search_args += "&rfcs=on&activedrafts=on&olddrafts=on"
    else:
        for t in doctypenames:
            if t.prefix and n.startswith(t.prefix):
                search_args += "&doctypes=%s" % t.slug
                break
        else:
            search_args += "&rfcs=on&activedrafts=on&olddrafts=on"

    return cached_redirect(cache_key, urlreverse('ietf.doc.views_search.search') + search_args)

def ad_dashboard_group(doc):

    if doc.type.slug=='draft':
        if doc.get_state_slug('draft') == 'rfc':
            return 'RFC'
        elif doc.get_state_slug('draft') == 'active' and doc.get_state_slug('draft-iesg'):
            return '%s Internet-Draft' % doc.get_state('draft-iesg').name
        else:
            return '%s Internet-Draft' % doc.get_state('draft').name
    elif doc.type.slug=='conflrev':
        if doc.get_state_slug('conflrev') in ('appr-reqnopub-sent','appr-noprob-sent'):
            return 'Approved Conflict Review'
        elif doc.get_state_slug('conflrev') in ('appr-reqnopub-pend','appr-noprob-pend','appr-reqnopub-pr','appr-noprob-pr'):
            return "%s Conflict Review" % State.objects.get(type__slug='draft-iesg',slug='approved')
        else:
          return '%s Conflict Review' % doc.get_state('conflrev')
    elif doc.type.slug=='statchg':
        if doc.get_state_slug('statchg') in ('appr-sent',):
            return 'Approved Status Change'
        if doc.get_state_slug('statchg') in ('appr-pend','appr-pr'):
            return '%s Status Change' % State.objects.get(type__slug='draft-iesg',slug='approved')
        else:
            return '%s Status Change' % doc.get_state('statchg')
    elif doc.type.slug=='charter':
        if doc.get_state_slug('charter') == 'approved':
            return "Approved Charter"
        else:
            return '%s Charter' % doc.get_state('charter')
    else:
        return "Document"

def ad_dashboard_sort_key(doc):

    if doc.type.slug=='draft' and doc.get_state_slug('draft') == 'rfc':
        return "21%04d" % int(doc.rfc_number())
    if doc.type.slug=='statchg' and doc.get_state_slug('statchg') == 'appr-sent':
        return "22%d" % 0 # TODO - get the date of the transition into this state here
    if doc.type.slug=='conflrev' and doc.get_state_slug('conflrev') in ('appr-reqnopub-sent','appr-noprob-sent'):
        return "23%d" % 0 # TODO - get the date of the transition into this state here
    if doc.type.slug=='charter' and doc.get_state_slug('charter') == 'approved':
        return "24%d" % 0 # TODO - get the date of the transition into this state here

    seed = ad_dashboard_group(doc)

    if doc.type.slug=='conflrev' and doc.get_state_slug('conflrev') == 'adrev':
        state = State.objects.get(type__slug='draft-iesg',slug='ad-eval')
        return "1%d%s" % (state.order,seed)

    if doc.type.slug=='charter' and doc.get_state_slug('charter') != 'replaced':
        if doc.get_state_slug('charter') in ('notrev','infrev'):
            return "100%s" % seed
        elif  doc.get_state_slug('charter') == 'intrev':
            state = State.objects.get(type__slug='draft-iesg',slug='ad-eval')
            return "1%d%s" % (state.order,seed)
        elif  doc.get_state_slug('charter') == 'extrev':
            state = State.objects.get(type__slug='draft-iesg',slug='lc')
            return "1%d%s" % (state.order,seed)
        elif  doc.get_state_slug('charter') == 'iesgrev':
            state = State.objects.get(type__slug='draft-iesg',slug='iesg-eva')
            return "1%d%s" % (state.order,seed)

    if doc.type.slug=='statchg' and  doc.get_state_slug('statchg') == 'adrev':
        state = State.objects.get(type__slug='draft-iesg',slug='ad-eval')
        return "1%d%s" % (state.order,seed)

    if seed.startswith('Needs Shepherd'):
        return "100%s" % seed
    if seed.endswith(' Document'):
        seed = seed[:-9]
    elif seed.endswith(' Internet-Draft'):
        seed = seed[:-15]
    elif seed.endswith(' Conflict Review'):
        seed = seed[:-16]
    elif seed.endswith(' Status Change'):
        seed = seed[:-14]
    state = State.objects.filter(type__slug='draft-iesg',name=seed)
    if state:
        ageseconds = 0
        changetime= doc.latest_event(type='changed_document')
        if changetime:
            ad = (datetime.datetime.now()-doc.latest_event(type='changed_document').time)
            ageseconds = (ad.microseconds + (ad.seconds + ad.days * 24 * 3600) * 10**6) / 10**6
        return "1%d%s%s%010d" % (state[0].order,seed,doc.type.slug,ageseconds)

    return "3%s" % seed

def docs_for_ad(request, name):
    ad = None
    responsible = Document.objects.values_list('ad', flat=True).distinct()
    for p in Person.objects.filter(Q(role__name__in=("pre-ad", "ad"),
                                     role__group__type="area",
                                     role__group__state="active")
                                   | Q(pk__in=responsible)).distinct():
        if name == p.full_name_as_key():
            ad = p
            break
    if not ad:
        raise Http404
    form = SearchForm({'by':'ad','ad': ad.id,
                       'rfcs':'on', 'activedrafts':'on', 'olddrafts':'on',
                       'sort': 'status',
                       'doctypes': list(DocTypeName.objects.filter(used=True).exclude(slug='draft').values_list("pk", flat=True))})
    results, meta = prepare_document_table(request, retrieve_search_results(form), form.data, max_results=500)
    results.sort(key=ad_dashboard_sort_key)
    del meta["headers"][-1]
    #
    for d in results:
        d.search_heading = ad_dashboard_group(d)
    #
    # Additional content showing docs with blocking positions by this ad
    blocked_docs = []
    if ad in get_active_ads():
        possible_docs = Document.objects.filter(Q(states__type="draft-iesg",
                                                  states__slug__in=IESG_BALLOT_ACTIVE_STATES) |
                                                Q(states__type="charter",
                                                  states__slug__in=("intrev", "iesgrev")) |
                                                Q(states__type__in=("statchg", "conflrev"),
                                                  states__slug__in=("iesgeval", "defer")),
                                                docevent__ballotpositiondocevent__pos__blocking=True,
                                                docevent__ballotpositiondocevent__balloter=ad).distinct()
        for doc in possible_docs:
            ballot = doc.active_ballot()
            if not ballot:
                continue

            blocking_positions = [p for p in ballot.all_positions() if p.pos.blocking]

            if not blocking_positions or not any( p.balloter==ad for p in blocking_positions ):
                continue

            augment_events_with_revision(doc, blocking_positions)

            doc.blocking_positions = blocking_positions
            doc.ballot = ballot

            blocked_docs.append(doc)

        # latest first
        if blocked_docs:
            blocked_docs.sort(key=lambda d: min(p.time for p in d.blocking_positions if p.balloter==ad), reverse=True)

    return render(request, 'doc/drafts_for_ad.html', {
        'form':form, 'docs':results, 'meta':meta, 'ad_name': ad.plain_name(), 'blocked_docs': blocked_docs
    })

def drafts_in_last_call(request):
    lc_state = State.objects.get(type="draft-iesg", slug="lc").pk
    form = SearchForm({'by':'state','state': lc_state, 'rfcs':'on', 'activedrafts':'on'})
    results, meta = prepare_document_table(request, retrieve_search_results(form), form.data)
    pages = 0
    for doc in results:
        pages += doc.pages

    return render(request, 'doc/drafts_in_last_call.html', {
        'form':form, 'docs':results, 'meta':meta, 'pages':pages
    })

def drafts_in_iesg_process(request):
    states = State.objects.filter(type="draft-iesg").exclude(slug__in=('idexists', 'pub', 'dead', 'watching', 'rfcqueue'))
    title = "Documents in IESG process"

    grouped_docs = []

    for s in states.order_by("order"):
        docs = Document.objects.filter(type="draft", states=s).distinct().order_by("time").select_related("ad", "group", "group__parent")
        if docs:
            if s.slug == "lc":
                for d in docs:
                    e = d.latest_event(LastCallDocEvent, type="sent_last_call")
                    d.lc_expires = e.expires if e else datetime.datetime.min
                docs = list(docs)
                docs.sort(key=lambda d: d.lc_expires)

            grouped_docs.append((s, docs))

    return render(request, 'doc/drafts_in_iesg_process.html', {
            "grouped_docs": grouped_docs,
            "title": title,
            })

def recent_drafts(request, days=7):
    since = datetime.datetime.now()-datetime.timedelta(days=days)
    state = State.objects.get(type='draft', slug='active')
    events = NewRevisionDocEvent.objects.filter(time__gt=since)
    names = [ e.doc.name for e in events ]
    docs = Document.objects.filter(name__in=names, states=state)
    results, meta = prepare_document_table(request, docs, query={'sort':'-date', }, max_results=len(names))
    pages = 0
    for doc in results:
        pages += doc.pages or 0

    return render(request, 'doc/recent_drafts.html', {
        'docs':results, 'meta':meta, 'pages':pages, 'days': days,
    })


def index_all_drafts(request):
    # try to be efficient since this view returns a lot of data
    categories = []

    for s in ("active", "rfc", "expired", "repl", "auth-rm", "ietf-rm"):
        state = State.objects.get(type="draft", slug=s)

        if state.slug == "rfc":
            heading = "RFCs"
        elif state.slug in ("ietf-rm", "auth-rm"):
            heading = "Internet-Drafts %s" % state.name
        else:
            heading = "%s Internet-Drafts" % state.name

        draft_names = DocAlias.objects.filter(docs__states=state).values_list("name", "docs__name")

        names = []
        names_to_skip = set()
        for name, doc in draft_names:
            sort_key = name
            if name != doc:
                if not name.startswith("rfc"):
                    name, doc = doc, name
                names_to_skip.add(doc)

            if name.startswith("rfc"):
                name = name.upper()
                sort_key = '%09d' % (100000000-int(name[3:]))

            names.append((name, sort_key))

        names.sort(key=lambda t: t[1])

        names = ['<a href="/doc/' + n + '/">' + n +'</a>'
                 for n, __ in names if n not in names_to_skip]

        categories.append((state,
                      heading,
                      len(names),
                      "<br>".join(names)
                      ))
    return render(request, 'doc/index_all_drafts.html', { "categories": categories })

def index_active_drafts(request):
    groups = active_drafts_index_by_group()

    return render(request, "doc/index_active_drafts.html", { 'groups': groups })

def ajax_select2_search_docs(request, model_name, doc_type):
    if model_name == "docalias":
        model = DocAlias
    else:
        model = Document

    q = [w.strip() for w in request.GET.get('q', '').split() if w.strip()]

    if not q:
        objs = model.objects.none()
    else:
        qs = model.objects.all()

        if model == Document:
            qs = qs.filter(type=doc_type)
        elif model == DocAlias:
            qs = qs.filter(docs__type=doc_type)

        for t in q:
            qs = qs.filter(name__icontains=t)

        objs = qs.distinct().order_by("name")[:20]

    return HttpResponse(select2_id_doc_name_json(objs), content_type='application/json')