from django.contrib.auth.decorators import login_required
from django.core.exceptions import ObjectDoesNotExist
from django.db.models import Sum
from django.http import HttpRequest, Http404
from django.shortcuts import render, get_object_or_404
from django.utils.translation import gettext_lazy as _

from compensation.forms import NewPaymentForm, NewStateModalForm, NewDeadlineModalForm
from compensation.models import Compensation, EcoAccount, Payment, CompensationState
from compensation.tables import CompensationTable, EcoAccountTable
from intervention.models import Intervention
from konova.contexts import BaseContext
from konova.decorators import *
from konova.forms import RemoveModalForm, SimpleGeomForm, NewDocumentForm
from konova.utils.message_templates import FORM_INVALID
from konova.utils.user_checks import in_group


@login_required
@any_group_check
def index_view(request: HttpRequest):
    """
    Renders the index view for compensation

    Args:
        request (HttpRequest): The incoming request

    Returns:
        A rendered view
    """
    template = "generic_index.html"
    compensations = Compensation.objects.filter(
        deleted=None,  # only show those which are not deleted individually
        intervention__deleted=None,  # and don't show the ones whose intervention has been deleted
    )
    table = CompensationTable(
        request=request,
        queryset=compensations
    )
    context = {
        "table": table,
    }
    context = BaseContext(request, context).context
    return render(request, template, context)


@login_required
@default_group_required
def new_view(request: HttpRequest):
    # ToDo
    pass


@login_required
@default_group_required
def edit_view(request: HttpRequest, id: str):
    # ToDo
    pass


@login_required
@any_group_check
def open_view(request: HttpRequest, id: str):
    """ Renders a detail view for a compensation

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

    Returns:

    """
    template = "compensation/detail/view.html"
    comp = get_object_or_404(Compensation, id=id)
    geom_form = SimpleGeomForm(instance=comp)
    _user = request.user
    is_data_shared = comp.intervention.is_shared_with(_user)

    # Order states according to surface
    before_states = comp.before_states.all().order_by("-surface")
    after_states = comp.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 = before_states.aggregate(Sum("surface"))["surface__sum"] or 0
    sum_after_states = after_states.aggregate(Sum("surface"))["surface__sum"] or 0
    diff_states = abs(sum_before_states - sum_after_states)

    context = {
        "comp": comp,
        "geom_form": geom_form,
        "has_access": is_data_shared,
        "before_states": before_states,
        "after_states": after_states,
        "sum_before_states": sum_before_states,
        "sum_after_states": sum_after_states,
        "diff_states": diff_states,
        "is_default_member": in_group(_user, _(DEFAULT_GROUP)),
        "is_zb_member": in_group(_user, _(ZB_GROUP)),
        "is_ets_member": in_group(_user, _(ETS_GROUP)),
    }
    context = BaseContext(request, context).context
    return render(request, template, context)


@login_required
def remove_view(request: HttpRequest, id: str):
    """ Renders a modal view for removing the compensation

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

    Returns:

    """
    comp = get_object_or_404(Compensation, id=id)
    form = RemoveModalForm(request.POST or None, instance=comp, user=request.user)
    return form.process_request(
        request=request,
        msg_success=_("Compensation removed"),
        redirect_url="",
    )


@login_required
@any_group_check
def account_index_view(request: HttpRequest):
    """
    Renders the index view for eco accounts

    Args:
        request (HttpRequest): The incoming request

    Returns:
        A rendered view
    """
    template = "generic_index.html"
    user = request.user
    eco_accounts = EcoAccount.objects.filter(
        deleted=None,
    )
    table = EcoAccountTable(
        request=request,
        queryset=eco_accounts
    )
    context = {
        "table": table,
    }
    context = BaseContext(request, context).context
    return render(request, template, context)


@login_required
@default_group_required
def account_new_view(request: HttpRequest):
    # ToDo
    pass


@login_required
@default_group_required
def account_edit_view(request: HttpRequest, id: str):
    # ToDo
    pass


@login_required
@any_group_check
def account_open_view(request: HttpRequest, id: str):
    # ToDo
    pass


@login_required
def account_remove_view(request: HttpRequest, id: str):
    # ToDo
    pass


@login_required
@default_group_required
def new_payment_view(request: HttpRequest, intervention_id: str):
    """ Renders a modal view for adding new payments

    Args:
        request (HttpRequest): The incoming request
        intervention_id (str): The intervention's id for which a new payment shall be added

    Returns:

    """
    intervention = get_object_or_404(Intervention, id=intervention_id)
    form = NewPaymentForm(request.POST or None, instance=intervention, user=request.user)
    template = form.template
    if request.method == "POST":
        if form.is_valid():
            payment = form.save()
            messages.success(
                request,
                _("Payment added")
            )
            return redirect(request.META.get("HTTP_REFERER", "home"))
        else:
            messages.info(
                request,
                FORM_INVALID
            )
            return redirect(request.META.get("HTTP_REFERER", "home"))
    elif request.method == "GET":
        context = {
            "form": form,
        }
        context = BaseContext(request, context).context
        return render(request, template, context)
    else:
        raise NotImplementedError


@login_required
@default_group_required
def payment_remove_view(request: HttpRequest, id: str):
    """ Renders a modal view for removing payments

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

    Returns:

    """
    payment = get_object_or_404(Payment, id=id)
    form = RemoveModalForm(request.POST or None, instance=payment, user=request.user)
    return form.process_request(
        request=request,
        msg_success=_("Payment removed"),
    )


@login_required
@default_group_required
def withdraw_remove_view(request: HttpRequest, id: str, withdraw_id: str):
    """ Renders a modal view for removing withdraws

    Args:
        request (HttpRequest): The incoming request
        id (str): The eco account's id
        withdraw_id (str): The withdraw's id

    Returns:

    """
    acc = get_object_or_404(EcoAccount, id=id)
    try:
        eco_withdraw = acc.eco_withdraws.get(id=withdraw_id)
    except ObjectDoesNotExist:
        raise Http404("Unknown withdraw")

    form = RemoveModalForm(request.POST or None, instance=eco_withdraw, user=request.user)
    return form.process_request(
        request=request,
        msg_success=_("Withdraw removed")
    )


@login_required
def new_document_view(request: HttpRequest, id: str):
    """ Renders a form for uploading new documents

    Args:
        request (HttpRequest): The incoming request
        id (str): The compensation's id to which the new document will be related
    Returns:

    """
    comp = get_object_or_404(Compensation, id=id)
    form = NewDocumentForm(request.POST or None, request.FILES or None, instance=comp, user=request.user)
    return form.process_request(
        request,
        msg_success=_("Document added")
    )


@login_required
def state_new_view(request: HttpRequest, id: str):
    """ Renders a form for adding new states for a compensation

    Args:
        request (HttpRequest): The incoming request
        id (str): The compensation's id to which the new state will be related

    Returns:

    """
    comp = get_object_or_404(Compensation, id=id)
    form = NewStateModalForm(request.POST or None, instance=comp, user=request.user)
    return form.process_request(
        request,
        msg_success=_("State added")
    )


@login_required
def deadline_new_view(request: HttpRequest, id: str):
    """ Renders a form for adding new states for a compensation

    Args:
        request (HttpRequest): The incoming request
        id (str): The compensation's id to which the new state will be related

    Returns:

    """
    comp = get_object_or_404(Compensation, id=id)
    form = NewDeadlineModalForm(request.POST or None, instance=comp, user=request.user)
    return form.process_request(
        request,
        msg_success=_("Deadline added")
    )


@login_required
def state_remove_view(request: HttpRequest, id: str):
    state = get_object_or_404(CompensationState, id=id)
    form = RemoveModalForm(request.POST or None, instance=state, user=request.user)
    return form.process_request(
        request,
        msg_success=_("State removed")
    )