from django.contrib.admin.models import LogEntry, ContentType, ADDITION, CHANGE, DELETION
from django.utils.translation import ugettext_lazy as _
from django.views.generic import DetailView


class LogBaseMixin(object):
    object = None
    request = None


class LogCreateMixin(LogBaseMixin):
    def form_valid(self, form):
        response = super(LogCreateMixin, self).form_valid(form)
        LogEntry.objects.log_action(
            user_id=self.request.user.pk,
            content_type_id=ContentType.objects.get_for_model(
                self.object, False).pk,
            object_id=self.object.pk,
            object_repr=str(self.object),
            action_flag=ADDITION,
            change_message=_('Adicionado')
        )
        return response


class LogChangeMixin(LogBaseMixin):
    def form_valid(self, form):
        response = super(LogChangeMixin, self).form_valid(form)
        try:
            fs_c = ''
            for fs in self.get_formsets():
                for fsf in fs.forms:
                    if fsf.changed_data:
                        fs_c += f'{fsf.instance} ' + \
                            ', '.join([str(fsf.fields.get(field).label) + ' de ' + str(fsf.initial.get(field)) + ' para ' +
                                       str(fsf.cleaned_data.get(field)) for field in fsf.changed_data])
        except Exception as e:
            fs_c = ''

        LogEntry.objects.log_action(
            user_id=self.request.user.pk,
            content_type_id=ContentType.objects.get_for_model(
                self.object, False).pk,
            object_id=self.object.pk,
            object_repr=str(self.object),
            action_flag=CHANGE,
            change_message=f'Modificado {", ".join([str(form.fields.get(field).label) for field in form.changed_data])}{(", " + fs_c) if fs_c != "" else ""}. '
        )
        return response


class LogDeleteMixin(LogBaseMixin):
    def delete(self, request, *args, **kwargs):
        obj = self.get_object()
        LogEntry.objects.log_action(
            user_id=self.request.user.pk,
            content_type_id=ContentType.objects.get_for_model(obj, False).pk,
            object_id=obj.pk,
            object_repr=str(obj),
            action_flag=DELETION,
            change_message=_('Deletado')
        )
        return super(LogDeleteMixin, self).delete(request, *args, **kwargs)


class HistoricView(DetailView):
    template_name = 'controle/historico.html'
    success_url = None

    def get_context_data(self, **kwargs):
        context = super(HistoricView, self).get_context_data(**kwargs)
        context.update({
            'log_entries': LogEntry.objects.filter(
                content_type=ContentType.objects.get_for_model(
                    self.get_object(), False),
                object_id=self.get_object().pk,
            )
        })
        return context


class LogFormsetCreateMixin(LogBaseMixin):
    def get_formsets(self):
        if self.request.POST:
            return [Formset(self.request.POST, self.request.FILES) for Formset in self.formset_classes]
        else:
            formsets = []

            for formset in self.formset_classes:
                prefix = formset().prefix
                if self.initial.get(prefix):
                    formsets.append(formset(initial=self.initial.get(prefix)))
                    self.initial.pop(prefix)
                else:
                    formsets.append(formset())

            return formsets

    def get_context_data(self, **kwargs):
        context = super(LogFormsetCreateMixin, self).get_context_data(**kwargs)
        context.update({
            'formsets': self.get_formsets()
        })
        return context

    def form_valid(self, form):
        formsets = self.get_formsets()
        response = super(LogFormsetCreateMixin, self).form_valid(form)

        for formset in formsets:
            if formset.cleaned_data != [{}]:
                if len(formset.cleaned_data) > 1:
                    LogEntry.objects.log_action(
                        user_id=self.request.user.pk,
                        content_type_id=ContentType.objects.get_for_model(
                            self.object, False).pk,
                        object_id=self.object.pk,
                        object_repr=str(self.object),
                        action_flag=ADDITION,
                        change_message=_(
                            f'{formset.forms[0].instance.__class__._meta.verbose_name_plural} adicionados')
                    )
                else:
                    LogEntry.objects.log_action(
                        user_id=self.request.user.pk,
                        content_type_id=ContentType.objects.get_for_model(
                            self.object, False).pk,
                        object_id=self.object.pk,
                        object_repr=str(self.object),
                        action_flag=ADDITION,
                        change_message=_(
                            f'{formset.forms[0].instance.__class__._meta.verbose_name} adicionado')
                    )

        return response


class FormSetCreateView(object):
    formset_classes = []
    initial = {}
    model = None
    object = None
    request = None

    def get_formsets(self):
        if self.request.POST:
            return [Formset(self.request.POST, self.request.FILES) for Formset in self.formset_classes]
        else:
            formsets = []

            for formset in self.formset_classes:
                prefix = formset().prefix
                if self.initial.get(prefix):
                    formsets.append(formset(initial=self.initial.get(prefix)))
                    self.initial.pop(prefix)
                else:
                    formsets.append(formset())

            return formsets

    def get_context_data(self, **kwargs):
        context = super(FormSetCreateView, self).get_context_data(**kwargs)
        context.update({
            'formsets': self.get_formsets()
        })
        return context

    def form_valid(self, form):
        formsets = self.get_formsets()
        if all([formset.is_valid() for formset in formsets]):
            response = super(FormSetCreateView, self).form_valid(form)

            for formset in formsets:
                formset.instance = self.object
                formset.save()

            return response
        else:
            return super(FormSetCreateView, self).form_invalid(form)


class FormSetUpdateView(object):
    formset_classes = []
    object = None
    request = None

    def get_formsets(self):
        if self.request.POST:
            formsets = [
                Formset(self.request.POST, self.request.FILES,
                        instance=self.object)
                for Formset in self.formset_classes
            ]
            for formset in formsets:
                formset.full_clean()
            return formsets
        else:
            return [Formset(instance=self.object) for Formset in self.formset_classes]

    def get_context_data(self, **kwargs):
        context = super(FormSetUpdateView, self).get_context_data(**kwargs)
        context.update({
            'formsets': self.get_formsets()
        })
        return context

    def form_valid(self, form):
        formsets = self.get_formsets()
        if all([formset.is_valid() for formset in formsets]):
            response = super(FormSetUpdateView, self).form_valid(form)

            for formset in formsets:
                formset.instance = self.object
                formset.save()

            return response
        else:
            return super(FormSetUpdateView, self).form_invalid(form)