# edit/create view for WGs

import re
import os
import datetime
import shutil

from django import forms
from django.shortcuts import render_to_response, get_object_or_404, redirect
from django.http import HttpResponseForbidden
from django.template import RequestContext
from django.utils.html import mark_safe
from django.http import Http404, HttpResponse

import debug                            # pyflakes:ignore

from ietf.doc.models import DocAlias, DocTagName, Document, State, save_document_in_history
from ietf.doc.utils import get_tags_for_stream_id
from ietf.group.models import ( Group, Role, GroupEvent, GroupHistory, GroupStateName,
    GroupStateTransitions, GroupTypeName, GroupURL, ChangeStateGroupEvent )
from ietf.group.utils import save_group_in_history
from ietf.ietfauth.utils import role_required, has_role
from ietf.person.forms import EmailsField
from ietf.person.models import Person, Email
from ietf.wginfo.mails import email_secretariat

MAX_GROUP_DELEGATES = 3

class WGForm(forms.Form):
    name = forms.CharField(max_length=255, label="Name", required=True)
    acronym = forms.CharField(max_length=10, label="Acronym", required=True)
    state = forms.ModelChoiceField(GroupStateName.objects.all(), label="State", required=True)
    chairs = EmailsField(label="Chairs", required=False)
    secretaries = EmailsField(label="Secretaries", required=False)
    techadv = EmailsField(label="Technical Advisors", required=False)
    delegates = EmailsField(label="Delegates", required=False, help_text=mark_safe("Type in name to search for person<br>Chairs can delegate the authority to update the state of group documents - max %s persons at a given time" % MAX_GROUP_DELEGATES))
    ad = forms.ModelChoiceField(Person.objects.filter(role__name="ad", role__group__state="active").order_by('name'), label="Shepherding AD", empty_label="(None)", required=False)
    parent = forms.ModelChoiceField(Group.objects.filter(type="area", state="active").order_by('name'), label="IETF Area", empty_label="(None)", required=False)
    list_email = forms.CharField(max_length=64, required=False)
    list_subscribe = forms.CharField(max_length=255, required=False)
    list_archive = forms.CharField(max_length=255, required=False)
    urls = forms.CharField(widget=forms.Textarea, label="Additional URLs", help_text="Format: http://site/path (Optional description). Separate multiple entries with newline.", required=False)

    def __init__(self, *args, **kwargs):
        self.wg = kwargs.pop('wg', None)
        self.confirmed = kwargs.pop('confirmed', False)

        super(self.__class__, self).__init__(*args, **kwargs)

        # if previous AD is now ex-AD, append that person to the list
        ad_pk = self.initial.get('ad')
        choices = self.fields['ad'].choices
        if ad_pk and ad_pk not in [pk for pk, name in choices]:
            self.fields['ad'].choices = list(choices) + [("", "-------"), (ad_pk, Person.objects.get(pk=ad_pk).plain_name())]

        self.confirm_msg = ""
        self.autoenable_confirm = False
        if self.wg:
            self.fields['acronym'].widget.attrs['readonly'] = True

    def clean_acronym(self):
        self.confirm_msg = ""
        self.autoenable_confirm = False

        # Changing the acronym of an already existing WG will cause 404s all
        # over the place, loose history, and generally muck up a lot of
        # things, so we don't permit it
        if self.wg:
            return self.wg.acronym # no change permitted

        acronym = self.cleaned_data['acronym'].strip().lower()

        # be careful with acronyms, requiring confirmation to take existing or override historic
        if not re.match(r'^[a-z][a-z0-9]+$', acronym):
            raise forms.ValidationError("Acronym is invalid, must be at least two characters and only contain lowercase letters and numbers starting with a letter.")

        existing = Group.objects.filter(acronym__iexact=acronym)
        if existing:
            existing = existing[0]

        if existing and existing.type_id == "wg":
            if self.confirmed:
                return acronym # take over confirmed

            if existing.state_id == "bof":
                self.confirm_msg = "Turn BoF %s into proposed WG and start chartering it" % existing.acronym
                self.autoenable_confirm = True
                raise forms.ValidationError("Warning: Acronym used for an existing BoF (%s)." % existing.name)
            else:
                self.confirm_msg = "Set state of %s WG to proposed and start chartering it" % existing.acronym
                self.autoenable_confirm = False
                raise forms.ValidationError("Warning: Acronym used for an existing WG (%s, %s)." % (existing.name, existing.state.name if existing.state else "unknown state"))

        if existing:
            raise forms.ValidationError("Acronym used for an existing group (%s)." % existing.name)

        old = GroupHistory.objects.filter(acronym__iexact=acronym, type="wg")
        if old and not self.confirmed:
            self.confirm_msg = "Confirm reusing acronym %s" % old[0].acronym
            self.autoenable_confirm = False
            raise forms.ValidationError("Warning: Acronym used for a historic WG.")

        return acronym

    def clean_urls(self):
        return [x.strip() for x in self.cleaned_data["urls"].splitlines() if x.strip()]

    def clean_delegates(self):
        if len(self.cleaned_data["delegates"]) > MAX_GROUP_DELEGATES:
            raise forms.ValidationError("At most %s delegates can be appointed at the same time, please remove %s delegates." % (
                    MAX_GROUP_DELEGATES, len(self.cleaned_data["delegates"]) - MAX_GROUP_DELEGATES))
        return self.cleaned_data["delegates"]


def format_urls(urls, fs="\n"):
    res = []
    for u in urls:
        if u.name:
            res.append(u"%s (%s)" % (u.url, u.name))
        else:
            res.append(u.url)
    return fs.join(res)

def get_or_create_initial_charter(wg):
    try:
        charter = Document.objects.get(docalias__name="charter-ietf-%s" % wg.acronym)
    except Document.DoesNotExist:
        charter = Document(
            name="charter-ietf-" + wg.acronym,
            type_id="charter",
            title=wg.name,
            group=wg,
            abstract=wg.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,
            document=charter
        )

    return charter

@role_required('Area Director', 'Secretariat')
def submit_initial_charter(request, acronym=None):
    wg = get_object_or_404(Group, acronym=acronym)
    if not wg.charter:
        wg.charter = get_or_create_initial_charter(wg)
        wg.save()
    return redirect('charter_submit', name=wg.charter.name, option="initcharter")
        
@role_required('Area Director', 'Secretariat')
def edit(request, acronym=None, action="edit"):
    """Edit or create a WG, notifying parties as
    necessary and logging changes as group events."""
    if action == "edit":
        wg = get_object_or_404(Group, acronym=acronym)
        new_wg = False
    elif action in ("create","charter"):
        wg = None
        new_wg = True
    else:
        raise Http404

    login = request.user.person

    if request.method == 'POST':
        form = WGForm(request.POST, wg=wg, confirmed=request.POST.get("confirmed", False))
        if form.is_valid():
            clean = form.cleaned_data
            if new_wg:
                try:
                    wg = Group.objects.get(acronym=clean["acronym"])
                    save_group_in_history(wg)
                    wg.time = datetime.datetime.now()
                    wg.save()
                except Group.DoesNotExist:
                    wg = Group.objects.create(name=clean["name"],
                                              acronym=clean["acronym"],
                                              type=GroupTypeName.objects.get(slug="wg"),
                                              state=clean["state"]
                                              )

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


            if action=="charter" and not wg.charter:  # make sure we have a charter
                wg.charter = get_or_create_initial_charter(wg)

            changes = []
                
            def desc(attr, new, old):
                entry = "%(attr)s changed to <b>%(new)s</b> from %(old)s"
                if new_wg:
                    entry = "%(attr)s changed to <b>%(new)s</b>"
                    
                return entry % dict(attr=attr, new=new, old=old)

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

            prev_acronym = wg.acronym

            # update the attributes, keeping track of what we're doing
            diff('name', "Name")
            diff('acronym', "Acronym")
            diff('state', "State")
            diff('ad', "Shepherding AD")
            diff('parent', "IETF Area")
            diff('list_email', "Mailing list email")
            diff('list_subscribe', "Mailing list subscribe address")
            diff('list_archive', "Mailing list archive")

            if not new_wg and wg.acronym != prev_acronym and wg.charter:
                save_document_in_history(wg.charter)
                DocAlias.objects.get_or_create(
                    name="charter-ietf-%s" % wg.acronym,
                    document=wg.charter,
                    )
                old = os.path.join(wg.charter.get_file_path(), 'charter-ietf-%s-%s.txt' % (prev_acronym, wg.charter.rev))
                if os.path.exists(old):
                    new = os.path.join(wg.charter.get_file_path(), 'charter-ietf-%s-%s.txt' % (wg.acronym, wg.charter.rev))
                    shutil.copy(old, new)

            # update roles
            for attr, slug, title in [('chairs', 'chair', "Chairs"), ('secretaries', 'secr', "Secretaries"), ('techadv', 'techadv', "Tech Advisors"), ('delegates', 'delegate', "Delegates")]:
                new = clean[attr]
                old = Email.objects.filter(role__group=wg, role__name=slug).select_related("person")
                if set(new) != set(old):
                    changes.append(desc(title,
                                        ", ".join(x.get_name() for x in new),
                                        ", ".join(x.get_name() for x in old)))
                    wg.role_set.filter(name=slug).delete()
                    for e in new:
                        Role.objects.get_or_create(name_id=slug, email=e, group=wg, person=e.person)

            # update urls
            new_urls = clean['urls']
            old_urls = format_urls(wg.groupurl_set.order_by('url'), ", ")
            if ", ".join(sorted(new_urls)) != old_urls:
                changes.append(desc('Urls', ", ".join(sorted(new_urls)), old_urls))
                wg.groupurl_set.all().delete()
                # Add new ones
                for u in new_urls:
                    m = re.search('(?P<url>[\w\d:#@%/;$()~_?\+-=\\\.&]+)( \((?P<name>.+)\))?', u)
                    if m:
                        if m.group('name'):
                            url = GroupURL(url=m.group('url'), name=m.group('name'), group=wg)
                        else:
                            url = GroupURL(url=m.group('url'), name='', group=wg)
                        url.save()

            wg.time = datetime.datetime.now()

            if changes and not new_wg:
                for c in changes:
                    GroupEvent.objects.create(group=wg, by=login, type="info_changed", desc=c)

            wg.save()

            if action=="charter":
                return redirect('charter_submit', name=wg.charter.name, option="initcharter")

            return redirect('group_charter', acronym=wg.acronym)
    else: # form.is_valid()
        if not new_wg:
            init = dict(name=wg.name,
                        acronym=wg.acronym,
                        state=wg.state,
                        chairs=Email.objects.filter(role__group=wg, role__name="chair"),
                        secretaries=Email.objects.filter(role__group=wg, role__name="secr"),
                        techadv=Email.objects.filter(role__group=wg, role__name="techadv"),
                        delegates=Email.objects.filter(role__group=wg, role__name="delegate"),
                        ad=wg.ad_id if wg.ad else None,
                        parent=wg.parent.id if wg.parent else None,
                        list_email=wg.list_email if wg.list_email else None,
                        list_subscribe=wg.list_subscribe if wg.list_subscribe else None,
                        list_archive=wg.list_archive if wg.list_archive else None,
                        urls=format_urls(wg.groupurl_set.all()),
                        )
        else:
            init = dict(ad=login.id if has_role(request.user, "Area Director") else None,
                        )
        form = WGForm(initial=init, wg=wg)

    return render_to_response('wginfo/edit.html',
                              dict(wg=wg,
                                   form=form,
                                   action=action,
                                   user=request.user,
                                   login=login),
                              context_instance=RequestContext(request))



class ConcludeForm(forms.Form):
    instructions = forms.CharField(widget=forms.Textarea(attrs={'rows': 30}), required=True)

@role_required('Area Director','Secretariat')
def conclude(request, acronym):
    """Request the closing of a WG, prompting for instructions."""
    wg = get_object_or_404(Group, acronym=acronym)

    login = request.user.person

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

            email_secretariat(request, wg, "Request closing of group", instructions)

            e = GroupEvent(group=wg, by=login)
            e.type = "requested_close"
            e.desc = "Requested closing group"
            e.save()

            return redirect('group_charter', acronym=wg.acronym)
    else:
        form = ConcludeForm()

    return render_to_response('wginfo/conclude.html',
                              dict(form=form,
                                   wg=wg),
                              context_instance=RequestContext(request))


def customize_workflow(request, acronym):
    MANDATORY_STATES = ('c-adopt', 'wg-doc', 'sub-pub')

    group = get_object_or_404(Group, acronym=acronym, type="wg")
    if not request.user.is_authenticated() or not (has_role(request.user, "Secretariat") or group.role_set.filter(name="chair", person__user=request.user)):
        return HttpResponseForbidden("You don't have permission to access this view")

    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.wginfo.edit.customize_workflow", 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-ietf', 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 = next_states

            return redirect("ietf.wginfo.edit.customize_workflow", 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.wginfo.edit.customize_workflow", 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("ietf"))
    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-ietf")
    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_to_response('wginfo/customize_workflow.html', {
            'group': group,
            'states': states,
            'tags': tags,
            }, RequestContext(request))