from django import forms
from django.contrib import messages
from django.core.exceptions import PermissionDenied
from django.core.files import File
from django.db import transaction
from django.db.models import Count
from django.forms import inlineformset_factory
from django.shortcuts import get_object_or_404, redirect
from django.urls import reverse
from django.utils.functional import cached_property
from django.utils.translation import ugettext_lazy as _
from django.views.generic import (
    CreateView, DeleteView, DetailView, FormView, ListView, UpdateView,
)

from pretix.base.models import Device, Organizer, Team, TeamInvite, User
from pretix.base.models.event import EventMetaProperty
from pretix.base.models.organizer import TeamAPIToken
from pretix.base.services.mail import SendMailException, mail
from pretix.control.forms.filter import OrganizerFilterForm
from pretix.control.forms.organizer import (
    DeviceForm, EventMetaPropertyForm, OrganizerDisplaySettingsForm,
    OrganizerForm, OrganizerSettingsForm, OrganizerUpdateForm, TeamForm,
)
from pretix.control.permissions import OrganizerPermissionRequiredMixin
from pretix.control.signals import nav_organizer
from pretix.control.views import PaginationMixin
from pretix.helpers.urls import build_absolute_uri
from pretix.presale.style import regenerate_organizer_css


class OrganizerList(PaginationMixin, ListView):
    model = Organizer
    context_object_name = 'organizers'
    template_name = 'pretixcontrol/organizers/index.html'

    def get_queryset(self):
        qs = Organizer.objects.all()
        if self.filter_form.is_valid():
            qs = self.filter_form.filter_qs(qs)
        if self.request.user.has_active_staff_session(self.request.session.session_key):
            return qs
        else:
            return qs.filter(pk__in=self.request.user.teams.values_list('organizer', flat=True))

    def get_context_data(self, **kwargs):
        ctx = super().get_context_data(**kwargs)
        ctx['filter_form'] = self.filter_form
        return ctx

    @cached_property
    def filter_form(self):
        return OrganizerFilterForm(data=self.request.GET, request=self.request)


class InviteForm(forms.Form):
    user = forms.EmailField(required=False, label=_('User'))


class TokenForm(forms.Form):
    name = forms.CharField(required=False, label=_('Token name'))


class OrganizerDetailViewMixin:
    def get_context_data(self, **kwargs):
        ctx = super().get_context_data(**kwargs)
        ctx['nav_organizer'] = []
        ctx['organizer'] = self.request.organizer

        for recv, retv in nav_organizer.send(sender=self.request.organizer, request=self.request,
                                             organizer=self.request.organizer):
            ctx['nav_organizer'] += retv
        ctx['nav_organizer'].sort(key=lambda n: n['label'])
        return ctx

    def get_object(self, queryset=None) -> Organizer:
        return self.request.organizer


class OrganizerDetail(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixin, DetailView):
    model = Organizer
    template_name = 'pretixcontrol/organizers/detail.html'
    permission = None
    context_object_name = 'organizer'

    def get_object(self, queryset=None) -> Organizer:
        return self.request.organizer

    def get_context_data(self, **kwargs):
        ctx = super().get_context_data(**kwargs)
        ctx['events'] = self.request.organizer.events.all()
        return ctx


class OrganizerTeamView(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixin, DetailView):
    model = Organizer
    template_name = 'pretixcontrol/organizers/teams.html'
    permission = 'can_change_permissions'
    context_object_name = 'organizer'


class OrganizerSettingsFormView(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixin, FormView):
    model = Organizer
    permission = 'can_change_organizer_settings'

    def get_form_kwargs(self):
        kwargs = super().get_form_kwargs()
        kwargs['obj'] = self.request.organizer
        return kwargs

    @transaction.atomic
    def post(self, request, *args, **kwargs):
        form = self.get_form()
        if form.is_valid():
            form.save()
            if form.has_changed():
                self.request.organizer.log_action(
                    'pretix.organizer.settings', user=self.request.user, data={
                        k: (form.cleaned_data.get(k).name
                            if isinstance(form.cleaned_data.get(k), File)
                            else form.cleaned_data.get(k))
                        for k in form.changed_data
                    }
                )
            messages.success(self.request, _('Your changes have been saved.'))
            return redirect(self.get_success_url())
        else:
            messages.error(self.request, _('We could not save your changes. See below for details.'))
            return self.get(request)


class OrganizerDisplaySettings(OrganizerSettingsFormView):
    model = Organizer
    form_class = OrganizerDisplaySettingsForm
    template_name = 'pretixcontrol/organizers/display.html'
    permission = 'can_change_organizer_settings'

    def get_success_url(self) -> str:
        return reverse('control:organizer.display', kwargs={
            'organizer': self.request.organizer.slug,
        })

    @transaction.atomic
    def post(self, request, *args, **kwargs):
        form = self.get_form()
        if form.is_valid():
            form.save()
            if form.has_changed():
                self.request.organizer.log_action(
                    'pretix.organizer.settings', user=self.request.user, data={
                        k: (form.cleaned_data.get(k).name
                            if isinstance(form.cleaned_data.get(k), File)
                            else form.cleaned_data.get(k))
                        for k in form.changed_data
                    }
                )
            regenerate_organizer_css.apply_async(args=(self.request.organizer.pk,))
            messages.success(self.request, _('Your changes have been saved. Please note that it can '
                                             'take a short period of time until your changes become '
                                             'active.'))
            return redirect(self.get_success_url())
        else:
            messages.error(self.request, _('We could not save your changes. See below for details.'))
            return self.get(request)


class OrganizerUpdate(OrganizerPermissionRequiredMixin, UpdateView):
    model = Organizer
    form_class = OrganizerUpdateForm
    template_name = 'pretixcontrol/organizers/edit.html'
    permission = 'can_change_organizer_settings'
    context_object_name = 'organizer'

    @cached_property
    def object(self) -> Organizer:
        return self.request.organizer

    def get_object(self, queryset=None) -> Organizer:
        return self.object

    @cached_property
    def sform(self):
        return OrganizerSettingsForm(
            obj=self.object,
            prefix='settings',
            data=self.request.POST if self.request.method == 'POST' else None,
            files=self.request.FILES if self.request.method == 'POST' else None
        )

    def get_context_data(self, *args, **kwargs) -> dict:
        context = super().get_context_data(*args, **kwargs)
        context['sform'] = self.sform
        context['formset'] = self.formset
        return context

    @transaction.atomic
    def form_valid(self, form):
        self.save_formset(self.object)
        self.sform.save()
        if self.sform.has_changed():
            self.request.organizer.log_action(
                'pretix.organizer.settings',
                user=self.request.user,
                data={
                    k: (self.sform.cleaned_data.get(k).name
                        if isinstance(self.sform.cleaned_data.get(k), File)
                        else self.sform.cleaned_data.get(k))
                    for k in self.sform.changed_data
                }
            )
        if form.has_changed():
            self.request.organizer.log_action(
                'pretix.organizer.changed',
                user=self.request.user,
                data={k: form.cleaned_data.get(k) for k in form.changed_data}
            )
        messages.success(self.request, _('Your changes have been saved.'))
        return super().form_valid(form)

    def get_form_kwargs(self):
        kwargs = super().get_form_kwargs()
        if self.request.user.has_active_staff_session(self.request.session.session_key):
            kwargs['domain'] = True
        return kwargs

    def get_success_url(self) -> str:
        return reverse('control:organizer.edit', kwargs={
            'organizer': self.request.organizer.slug,
        })

    def post(self, request, *args, **kwargs):
        self.object = self.get_object()
        form = self.get_form()
        if form.is_valid() and self.sform.is_valid() and self.formset.is_valid():
            return self.form_valid(form)
        else:
            return self.form_invalid(form)

    @cached_property
    def formset(self):
        formsetclass = inlineformset_factory(
            Organizer, EventMetaProperty,
            form=EventMetaPropertyForm, can_order=False, can_delete=True, extra=0
        )
        return formsetclass(self.request.POST if self.request.method == "POST" else None,
                            instance=self.object, queryset=self.object.meta_properties.all())

    def save_formset(self, obj):
        for form in self.formset.initial_forms:
            if form in self.formset.deleted_forms:
                if not form.instance.pk:
                    continue
                form.instance.delete()
                form.instance.pk = None
            elif form.has_changed():
                form.save()

        for form in self.formset.extra_forms:
            if not form.has_changed():
                continue
            if self.formset._should_delete_form(form):
                continue
            form.instance.organizer = obj
            form.save()


class OrganizerCreate(CreateView):
    model = Organizer
    form_class = OrganizerForm
    template_name = 'pretixcontrol/organizers/create.html'
    context_object_name = 'organizer'

    def dispatch(self, request, *args, **kwargs):
        if not request.user.has_active_staff_session(self.request.session.session_key):
            raise PermissionDenied()  # TODO
        return super().dispatch(request, *args, **kwargs)

    @transaction.atomic
    def form_valid(self, form):
        messages.success(self.request, _('The new organizer has been created.'))
        ret = super().form_valid(form)
        t = Team.objects.create(
            organizer=form.instance, name=_('Administrators'),
            all_events=True, can_create_events=True, can_change_teams=True,
            can_change_organizer_settings=True, can_change_event_settings=True, can_change_items=True,
            can_view_orders=True, can_change_orders=True, can_view_vouchers=True, can_change_vouchers=True
        )
        t.members.add(self.request.user)
        return ret

    def get_success_url(self) -> str:
        return reverse('control:organizers')


class TeamListView(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixin, ListView):
    model = Team
    template_name = 'pretixcontrol/organizers/teams.html'
    permission = 'can_change_teams'
    context_object_name = 'teams'

    def get_queryset(self):
        return self.request.organizer.teams.annotate(
            memcount=Count('members', distinct=True),
            eventcount=Count('limit_events', distinct=True),
            invcount=Count('invites', distinct=True)
        ).all()


class TeamCreateView(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixin, CreateView):
    model = Team
    template_name = 'pretixcontrol/organizers/team_edit.html'
    permission = 'can_change_teams'
    form_class = TeamForm

    def get_form_kwargs(self):
        kwargs = super().get_form_kwargs()
        kwargs['organizer'] = self.request.organizer
        return kwargs

    def get_object(self, queryset=None):
        return get_object_or_404(Team, organizer=self.request.organizer, pk=self.kwargs.get('team'))

    def get_success_url(self):
        return reverse('control:organizer.team', kwargs={
            'organizer': self.request.organizer.slug,
            'team': self.object.pk
        })

    def form_valid(self, form):
        messages.success(self.request, _('The team has been created. You can now add members to the team.'))
        form.instance.organizer = self.request.organizer
        ret = super().form_valid(form)
        form.instance.members.add(self.request.user)
        form.instance.log_action('pretix.team.created', user=self.request.user, data={
            k: getattr(self.object, k) if k != 'limit_events' else [e.id for e in getattr(self.object, k).all()]
            for k in form.changed_data
        })
        return ret

    def form_invalid(self, form):
        messages.error(self.request, _('Your changes could not be saved.'))
        return super().form_invalid(form)


class TeamUpdateView(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixin, UpdateView):
    model = Team
    template_name = 'pretixcontrol/organizers/team_edit.html'
    permission = 'can_change_teams'
    context_object_name = 'team'
    form_class = TeamForm

    def get_form_kwargs(self):
        kwargs = super().get_form_kwargs()
        kwargs['organizer'] = self.request.organizer
        return kwargs

    def get_object(self, queryset=None):
        return get_object_or_404(Team, organizer=self.request.organizer, pk=self.kwargs.get('team'))

    def get_success_url(self):
        return reverse('control:organizer.team', kwargs={
            'organizer': self.request.organizer.slug,
            'team': self.object.pk
        })

    def form_valid(self, form):
        if form.has_changed():
            self.object.log_action('pretix.team.changed', user=self.request.user, data={
                k: getattr(self.object, k) if k != 'limit_events' else [e.id for e in getattr(self.object, k).all()]
                for k in form.changed_data
            })
        messages.success(self.request, _('Your changes have been saved.'))
        return super().form_valid(form)

    def form_invalid(self, form):
        messages.error(self.request, _('Your changes could not be saved.'))
        return super().form_invalid(form)


class TeamDeleteView(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixin, DeleteView):
    model = Team
    template_name = 'pretixcontrol/organizers/team_delete.html'
    permission = 'can_change_teams'
    context_object_name = 'team'

    def get_object(self, queryset=None):
        return get_object_or_404(Team, organizer=self.request.organizer, pk=self.kwargs.get('team'))

    def get_success_url(self):
        return reverse('control:organizer.teams', kwargs={
            'organizer': self.request.organizer.slug,
        })

    def get_context_data(self, *args, **kwargs) -> dict:
        context = super().get_context_data(*args, **kwargs)
        context['possible'] = self.is_allowed()
        return context

    def is_allowed(self) -> bool:
        return self.request.organizer.teams.exclude(pk=self.kwargs.get('team')).filter(
            can_change_teams=True, members__isnull=False
        ).exists()

    @transaction.atomic
    def delete(self, request, *args, **kwargs):
        success_url = self.get_success_url()
        self.object = self.get_object()
        if self.is_allowed():
            self.object.log_action('pretix.team.deleted', user=self.request.user)
            self.object.delete()
            messages.success(request, _('The selected team has been deleted.'))
            return redirect(success_url)
        else:
            messages.error(request, _('The selected team cannot be deleted.'))
            return redirect(success_url)


class TeamMemberView(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixin, DetailView):
    template_name = 'pretixcontrol/organizers/team_members.html'
    context_object_name = 'team'
    permission = 'can_change_teams'
    model = Team

    def get_object(self, queryset=None):
        return get_object_or_404(Team, organizer=self.request.organizer, pk=self.kwargs.get('team'))

    @cached_property
    def add_form(self):
        return InviteForm(data=(self.request.POST
                                if self.request.method == "POST" and "user" in self.request.POST else None))

    @cached_property
    def add_token_form(self):
        return TokenForm(data=(self.request.POST
                               if self.request.method == "POST" and "name" in self.request.POST else None))

    def get_context_data(self, **kwargs):
        ctx = super().get_context_data(**kwargs)
        ctx['add_form'] = self.add_form
        ctx['add_token_form'] = self.add_token_form
        return ctx

    def _send_invite(self, instance):
        try:
            mail(
                instance.email,
                _('pretix account invitation'),
                'pretixcontrol/email/invitation.txt',
                {
                    'user': self,
                    'organizer': self.request.organizer.name,
                    'team': instance.team.name,
                    'url': build_absolute_uri('control:auth.invite', kwargs={
                        'token': instance.token
                    })
                },
                event=None,
                locale=self.request.LANGUAGE_CODE
            )
        except SendMailException:
            pass  # Already logged

    @transaction.atomic
    def post(self, request, *args, **kwargs):
        self.object = self.get_object()

        if 'remove-member' in request.POST:
            try:
                user = User.objects.get(pk=request.POST.get('remove-member'))
            except User.DoesNotExist:
                pass
            else:
                other_admin_teams = self.request.organizer.teams.exclude(pk=self.object.pk).filter(
                    can_change_teams=True, members__isnull=False
                ).exists()
                if not other_admin_teams and self.object.can_change_teams and self.object.members.count() == 1:
                    messages.error(self.request, _('You cannot remove the last member from this team as no one would '
                                                   'be left with the permission to change teams.'))
                    return redirect(self.get_success_url())
                else:
                    self.object.members.remove(user)
                    self.object.log_action(
                        'pretix.team.member.removed', user=self.request.user, data={
                            'email': user.email,
                            'user': user.pk
                        }
                    )
                    messages.success(self.request, _('The member has been removed from the team.'))
                    return redirect(self.get_success_url())

        elif 'remove-invite' in request.POST:
            try:
                invite = self.object.invites.get(pk=request.POST.get('remove-invite'))
            except TeamInvite.DoesNotExist:
                messages.error(self.request, _('Invalid invite selected.'))
                return redirect(self.get_success_url())
            else:
                invite.delete()
                self.object.log_action(
                    'pretix.team.invite.deleted', user=self.request.user, data={
                        'email': invite.email
                    }
                )
                messages.success(self.request, _('The invite has been revoked.'))
                return redirect(self.get_success_url())

        elif 'remove-token' in request.POST:
            try:
                token = self.object.tokens.get(pk=request.POST.get('remove-token'))
            except TeamAPIToken.DoesNotExist:
                messages.error(self.request, _('Invalid token selected.'))
                return redirect(self.get_success_url())
            else:
                token.active = False
                token.save()
                self.object.log_action(
                    'pretix.team.token.deleted', user=self.request.user, data={
                        'name': token.name
                    }
                )
                messages.success(self.request, _('The token has been revoked.'))
                return redirect(self.get_success_url())

        elif "user" in self.request.POST and self.add_form.is_valid() and self.add_form.has_changed():

            try:
                user = User.objects.get(email=self.add_form.cleaned_data['user'])
            except User.DoesNotExist:
                if self.object.invites.filter(email=self.add_form.cleaned_data['user']).exists():
                    messages.error(self.request, _('This user already has been invited for this team.'))
                    return self.get(request, *args, **kwargs)

                invite = self.object.invites.create(email=self.add_form.cleaned_data['user'])
                self._send_invite(invite)
                self.object.log_action(
                    'pretix.team.invite.created', user=self.request.user, data={
                        'email': self.add_form.cleaned_data['user']
                    }
                )
                messages.success(self.request, _('The new member has been invited to the team.'))
                return redirect(self.get_success_url())
            else:
                if self.object.members.filter(pk=user.pk).exists():
                    messages.error(self.request, _('This user already has permissions for this team.'))
                    return self.get(request, *args, **kwargs)

                self.object.members.add(user)
                self.object.log_action(
                    'pretix.team.member.added', user=self.request.user,
                    data={
                        'email': user.email,
                        'user': user.pk,
                    }
                )
                messages.success(self.request, _('The new member has been added to the team.'))
                return redirect(self.get_success_url())

        elif "name" in self.request.POST and self.add_token_form.is_valid() and self.add_token_form.has_changed():
            token = self.object.tokens.create(name=self.add_token_form.cleaned_data['name'])
            self.object.log_action(
                'pretix.team.token.created', user=self.request.user, data={
                    'name': self.add_token_form.cleaned_data['name'],
                    'id': token.pk
                }
            )
            messages.success(self.request, _('A new API token has been created with the following secret: {}\n'
                                             'Please copy this secret to a safe place. You will not be able to '
                                             'view it again here.').format(token.token))
            return redirect(self.get_success_url())
        else:
            messages.error(self.request, _('Your changes could not be saved.'))
            return self.get(request, *args, **kwargs)

    def get_success_url(self) -> str:
        return reverse('control:organizer.team', kwargs={
            'organizer': self.request.organizer.slug,
            'team': self.object.pk
        })


class DeviceListView(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixin, ListView):
    model = Device
    template_name = 'pretixcontrol/organizers/devices.html'
    permission = 'can_change_organizer_settings'
    context_object_name = 'devices'

    def get_queryset(self):
        return self.request.organizer.devices.prefetch_related('limit_events')


class DeviceCreateView(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixin, CreateView):
    model = Device
    template_name = 'pretixcontrol/organizers/device_edit.html'
    permission = 'can_change_organizer_settings'
    form_class = DeviceForm

    def get_form_kwargs(self):
        kwargs = super().get_form_kwargs()
        kwargs['organizer'] = self.request.organizer
        return kwargs

    def get_success_url(self):
        return reverse('control:organizer.device.connect', kwargs={
            'organizer': self.request.organizer.slug,
            'device': self.object.pk
        })

    def form_valid(self, form):
        form.instance.organizer = self.request.organizer
        ret = super().form_valid(form)
        form.instance.members.add(self.request.user)
        form.instance.log_action('pretix.device.created', user=self.request.user, data={
            k: getattr(self.object, k) if k != 'limit_events' else [e.id for e in getattr(self.object, k).all()]
            for k in form.changed_data
        })
        return ret

    def form_invalid(self, form):
        messages.error(self.request, _('Your changes could not be saved.'))
        return super().form_invalid(form)


class DeviceUpdateView(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixin, UpdateView):
    model = Device
    template_name = 'pretixcontrol/organizers/device_edit.html'
    permission = 'can_change_organizer_settings'
    context_object_name = 'device'
    form_class = DeviceForm

    def get_form_kwargs(self):
        kwargs = super().get_form_kwargs()
        kwargs['organizer'] = self.request.organizer
        return kwargs

    def get_object(self, queryset=None):
        return get_object_or_404(Device, organizer=self.request.organizer, pk=self.kwargs.get('device'))

    def get_success_url(self):
        return reverse('control:organizer.devices', kwargs={
            'organizer': self.request.organizer.slug,
        })

    def form_valid(self, form):
        if form.has_changed():
            self.object.log_action('pretix.device.changed', user=self.request.user, data={
                k: getattr(self.object, k) if k != 'limit_events' else [e.id for e in getattr(self.object, k).all()]
                for k in form.changed_data
            })
        messages.success(self.request, _('Your changes have been saved.'))
        return super().form_valid(form)

    def form_invalid(self, form):
        messages.error(self.request, _('Your changes could not be saved.'))
        return super().form_invalid(form)


class DeviceConnectView(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixin, DetailView):
    model = Device
    template_name = 'pretixcontrol/organizers/device_connect.html'
    permission = 'can_change_organizer_settings'
    context_object_name = 'device'
    form_class = DeviceForm

    def get_object(self, queryset=None):
        return get_object_or_404(Device, organizer=self.request.organizer, pk=self.kwargs.get('device'))

    def get(self, request, *args, **kwargs):
        self.object = self.get_object()
        if self.object.initialized:
            messages.error(request, _('This device already has been connected.'))
            return redirect(reverse('control:organizer.devices', kwargs={
                'organizer': self.request.organizer.slug,
            }))
        return super().get(request, *args, **kwargs)