"""
Author: Michel Peltriaux
Organization: Struktur- und Genehmigungsdirektion Nord, Rhineland-Palatinate, Germany
Contact: ksp-servicestelle@sgdnord.rlp.de
Created on: 19.08.22

"""
from django.contrib.auth.decorators import login_required
from django.contrib.auth.mixins import LoginRequiredMixin
from django.http import HttpRequest
from django.shortcuts import get_object_or_404
from django.urls import reverse
from django.utils.translation import gettext_lazy as _

from ema.forms import NewEmaForm, EditEmaForm
from ema.models import Ema
from ema.tables import EmaTable
from konova.decorators import shared_access_required, conservation_office_group_required, login_required_modal
from konova.forms.modals import RemoveModalForm
from konova.views.base import BaseIndexView, BaseIdentifierGeneratorView, BaseNewSpatialLocatedObjectFormView, \
    BaseEditSpatialLocatedObjectFormView
from konova.views.detail import BaseDetailView


class EmaIndexView(LoginRequiredMixin, BaseIndexView):
    _TAB_TITLE = _("EMAs - Overview")
    _INDEX_TABLE_CLS = EmaTable

    def _get_queryset(self):
        qs = Ema.objects.filter(
            deleted=None,
        ).order_by(
            "-modified__timestamp"
        )
        return qs


class NewEmaFormView(BaseNewSpatialLocatedObjectFormView):
    _FORM_CLS = NewEmaForm
    _MODEL_CLS = Ema
    _TEMPLATE = "ema/form/view.html"
    _TAB_TITLE = _("New EMA")
    _REDIRECT_URL = "ema:detail"

    def _user_has_permission(self, user):
        # User has to be an ets user
        return user.is_ets_user()


class EditEmaFormView(BaseEditSpatialLocatedObjectFormView):
    _MODEL_CLS = Ema
    _FORM_CLS = EditEmaForm
    _TEMPLATE = "ema/form/view.html"
    _REDIRECT_URL = "ema:detail"
    _TAB_TITLE = _("Edit {}")

    def _user_has_permission(self, user):
        # User has to be an ets user
        return user.is_ets_user()


class EmaIdentifierGeneratorView(LoginRequiredMixin, BaseIdentifierGeneratorView):
    _MODEL_CLS = Ema
    _REDIRECT_URL = "ema:index"

    def _user_has_permission(self, user):
        return user.is_ets_user()


class EmaDetailView(BaseDetailView):
    _MODEL_CLS = Ema
    _TEMPLATE = "ema/detail/view.html"

    def _get_object(self, id: str):
        """ Fetch object for detail view

        Args:
            id (str): The record's id'

        Returns:

        """
        ema = get_object_or_404(Ema, id=id, deleted=None)
        return ema

    def _get_detail_context(self, obj: Ema):
        """ Generate object specific detail context for  view

        Args:
            obj (): The record

        Returns:

        """
        # Order states according to surface
        before_states = obj.before_states.all().order_by("-surface")
        after_states = obj.after_states.all().order_by("-surface")

        # Precalculate logical errors between before- and after-states
        # Sum() returns None in case of no states, so we catch that and replace it with 0 for easier handling
        sum_before_states = obj.get_surface_before_states()
        sum_after_states = obj.get_surface_after_states()
        diff_states = abs(sum_before_states - sum_after_states)

        context = {
            "before_states": before_states,
            "after_states": after_states,
            "sum_before_states": sum_before_states,
            "sum_after_states": sum_after_states,
            "diff_states": diff_states,
            "has_finished_deadlines": obj.get_finished_deadlines().exists(),
        }
        return context


@login_required_modal
@login_required
@conservation_office_group_required
@shared_access_required(Ema, "id")
def remove_view(request: HttpRequest, id: str):
    """ Renders a modal view for removing the EMA

    Args:
        request (HttpRequest): The incoming request
        id (str): The EMA's id

    Returns:

    """
    ema = get_object_or_404(Ema, id=id)
    form = RemoveModalForm(request.POST or None, instance=ema, request=request)
    return form.process_request(
        request=request,
        msg_success=_("EMA removed"),
        redirect_url=reverse("ema:index"),
    )