import heapq
import statistics
from collections import defaultdict
from datetime import datetime, timedelta
from decimal import Decimal
from typing import List, Tuple
from urllib.parse import urlencode

from asgiref.sync import async_to_sync
from channels.layers import get_channel_layer
from django.conf import settings
from django.contrib import messages
from django.contrib.auth.decorators import login_required, permission_required
from django.contrib.auth.mixins import PermissionRequiredMixin
from django.contrib.auth.models import Permission, User
from django.contrib.messages.views import SuccessMessageMixin
from django.core.exceptions import SuspiciousOperation
from django.core.mail import EmailMessage
from django.db import transaction
from django.db.models import (
    Count,
    DecimalField,
    ExpressionWrapper,
    F,
    Max,
    OuterRef,
    Prefetch,
    Q,
    Subquery,
    Sum,
)
from django.forms import ValidationError, formset_factory
from django.http import (
    Http404,
    HttpResponseBadRequest,
    HttpResponseForbidden,
    JsonResponse,
)
from django.shortcuts import get_object_or_404, redirect, render
from django.template import loader
from django.urls import reverse, reverse_lazy
from django.utils import timezone
from django.utils.decorators import method_decorator
from django.views.generic import DetailView, FormView, ListView, TemplateView
from django.views.generic.detail import BaseDetailView
from django.views.generic.edit import CreateView, DeleteView, UpdateView

from gestioncof.models import CofProfile
from kfet import KFET_DELETED_TRIGRAMME
from kfet.auth.decorators import kfet_password_auth
from kfet.autocomplete import kfet_account_only_autocomplete, kfet_autocomplete
from kfet.config import kfet_config
from kfet.decorators import teamkfet_required
from kfet.forms import (
    AccountForm,
    AccountFrozenForm,
    AccountNoTriForm,
    AccountPwdForm,
    AccountStatForm,
    AccountTriForm,
    AddcostForm,
    ArticleForm,
    ArticleRestrictForm,
    CategoryForm,
    CheckoutForm,
    CheckoutRestrictForm,
    CheckoutStatementCreateForm,
    CheckoutStatementUpdateForm,
    CofForm,
    ContactForm,
    DemandeSoireeForm,
    FilterHistoryForm,
    InventoryArticleForm,
    KFetConfigForm,
    KPsulAccountForm,
    KPsulCheckoutForm,
    KPsulOperationFormSet,
    KPsulOperationGroupForm,
    OrderArticleForm,
    OrderArticleToInventoryForm,
    StatScaleForm,
    TransferFormSet,
    UserForm,
    UserGroupForm,
    UserInfoForm,
)
from kfet.models import (
    Account,
    AccountNegative,
    Article,
    ArticleCategory,
    Checkout,
    CheckoutStatement,
    Inventory,
    InventoryArticle,
    Operation,
    OperationGroup,
    Order,
    OrderArticle,
    Supplier,
    SupplierArticle,
    Transfer,
    TransferGroup,
)
from kfet.statistic import SCALE_DICT, DayScale, MonthScale, WeekScale, scale_url_params
from shared.views import AutocompleteView

from .auth import KFET_GENERIC_TRIGRAMME
from .auth.views import (  # noqa
    AccountGroupCreate,
    AccountGroupUpdate,
    account_group,
    login_generic,
)


def put_cleaned_data_in_dict(dict, form):
    for field in form.cleaned_data:
        dict[field] = form.cleaned_data[field]


class ContactView(FormView):
    template_name = "kfet/contact.html"
    form_class = ContactForm
    success_url = reverse_lazy("kfet.contact")

    def form_valid(self, form):
        # Envoie un mail lorsque le formulaire est valide
        EmailMessage(
            form.cleaned_data["subject"],
            form.cleaned_data["message"],
            from_email=form.cleaned_data["from_email"],
            to=("chefs-k-fet@ens.psl.eu",),
        ).send()

        messages.success(
            self.request,
            "Votre message a bien été envoyé aux Wo·men K-Fêt.",
        )

        return super().form_valid(form)


class DemandeSoireeView(FormView):
    template_name = "kfet/demande_soiree.html"
    form_class = DemandeSoireeForm
    success_url = reverse_lazy("kfet.demande-soiree")

    def form_valid(self, form):
        destinataires = ["chefs-k-fet@ens.psl.eu"]

        if form.cleaned_data["contact_boum"]:
            destinataires.append("boum@ens.psl.eu")

        if form.cleaned_data["contact_pls"]:
            destinataires.append("pls@ens.psl.eu")

        # Envoie un mail lorsque le formulaire est valide
        EmailMessage(
            f"Demande de soirée le {form.cleaned_data['date']}",
            loader.render_to_string(
                "kfet/mails/demande_soiree.txt", context=form.cleaned_data
            ),
            from_email=form.cleaned_data["from_email"],
            to=destinataires,
            cc=[form.cleaned_data["from_email"]],
        ).send()

        messages.success(
            self.request,
            "Votre demande de soirée a bien été envoyée.",
        )

        return super().form_valid(form)


# -----
# Account views
# -----

# Account - General


@login_required
@teamkfet_required
def account(request):
    accounts = Account.objects.select_related("cofprofile__user").order_by("trigramme")
    return render(request, "kfet/account.html", {"accounts": accounts})


@login_required
@teamkfet_required
def account_is_validandfree_ajax(request):
    if not request.GET.get("trigramme", ""):
        raise Http404
    trigramme = request.GET.get("trigramme")
    data = Account.is_validandfree(trigramme)
    return JsonResponse(data)


# Account - Create


@login_required
@teamkfet_required
@kfet_password_auth
def account_create(request):
    # Enregistrement
    if request.method == "POST":
        trigramme_form = AccountTriForm(request.POST)

        # Peuplement des forms
        username = request.POST.get("username")
        login_clipper = request.POST.get("login_clipper")

        forms = get_account_create_forms(
            request, username=username, login_clipper=login_clipper
        )

        account_form = forms["account_form"]
        cof_form = forms["cof_form"]
        user_form = forms["user_form"]

        if all(
            (
                user_form.is_valid(),
                cof_form.is_valid(),
                trigramme_form.is_valid(),
                account_form.is_valid(),
            )
        ):
            # Checking permission
            if not request.user.has_perm("kfet.add_account"):
                messages.error(
                    request, "Permission refusée", extra_tags="permission-denied"
                )
            else:
                data = {}
                # Fill data for Account.save()
                put_cleaned_data_in_dict(data, user_form)
                put_cleaned_data_in_dict(data, cof_form)

                try:
                    account = trigramme_form.save(data=data)
                    account_form = AccountNoTriForm(request.POST, instance=account)
                    account_form.save()
                    messages.success(request, "Compte créé : %s" % account.trigramme)
                    account.send_creation_email()
                    return redirect("kfet.account.create")
                except Account.UserHasAccount as e:
                    messages.error(
                        request,
                        "Cet utilisateur a déjà un compte K-Fêt : %s" % e.trigramme,
                    )
    else:
        initial = {"trigramme": request.GET.get("trigramme", "")}
        trigramme_form = AccountTriForm(initial=initial)
        account_form = None
        cof_form = None
        user_form = None

    return render(
        request,
        "kfet/account_create.html",
        {
            "trigramme_form": trigramme_form,
            "account_form": account_form,
            "cof_form": cof_form,
            "user_form": user_form,
        },
    )


def account_form_set_readonly_fields(user_form, cof_form):
    user_form.fields["username"].widget.attrs["readonly"] = True
    user_form.fields["first_name"].widget.attrs["readonly"] = True
    user_form.fields["last_name"].widget.attrs["readonly"] = True
    user_form.fields["email"].widget.attrs["readonly"] = True
    cof_form.fields["login_clipper"].widget.attrs["readonly"] = True
    cof_form.fields["departement"].widget.attrs["readonly"] = True
    cof_form.fields["is_cof"].widget.attrs["disabled"] = True


def get_account_create_forms(
    request=None, username=None, login_clipper=None, fullname=None
):
    user = None
    clipper = False
    if login_clipper and (login_clipper == username or not username):
        # à partir d'un clipper
        # le user associé à ce clipper ne devrait pas encore exister
        clipper = True
        try:
            # Vérification que clipper ne soit pas déjà dans User
            user = User.objects.get(username=login_clipper)
            # Ici, on nous a menti, le user existe déjà
            username = user.username
            clipper = False
        except User.DoesNotExist:
            # Clipper (sans user déjà existant)

            # UserForm - Prefill
            user_initial = {
                "username": login_clipper,
                "email": "%s@clipper.ens.fr" % login_clipper,
            }
            if fullname:
                # Prefill du nom et prénom
                names = fullname.split()
                # Le premier, c'est le prénom
                user_initial["first_name"] = names[0]
                if len(names) > 1:
                    # Si d'autres noms -> tous dans le nom de famille
                    user_initial["last_name"] = " ".join(names[1:])
            # CofForm - Prefill
            cof_initial = {"login_clipper": login_clipper}

            # Form créations
            if request:
                user_form = UserForm(request.POST, initial=user_initial)
                cof_form = CofForm(request.POST, initial=cof_initial)
            else:
                user_form = UserForm(initial=user_initial)
                cof_form = CofForm(initial=cof_initial)

            # Protection (read-only) des champs username et login_clipper
            account_form_set_readonly_fields(user_form, cof_form)
    if username and not clipper:
        try:
            user = User.objects.get(username=username)
            # le user existe déjà
            # récupération du profil cof
            (cof, _) = CofProfile.objects.get_or_create(user=user)
            # UserForm + CofForm - Création à partir des instances existantes
            if request:
                user_form = UserForm(request.POST, instance=user)
                cof_form = CofForm(request.POST, instance=cof)
            else:
                user_form = UserForm(instance=user)
                cof_form = CofForm(instance=cof)
            # Protection (read-only) des champs username, login_clipper et is_cof
            account_form_set_readonly_fields(user_form, cof_form)
        except User.DoesNotExist:
            # le username donnée n'existe pas -> Création depuis rien
            # (éventuellement en cours avec erreurs précédemment)
            pass
    if not user and not clipper:
        # connaît pas du tout, faut tout remplir
        if request:
            user_form = UserForm(request.POST)
            cof_form = CofForm(request.POST)
        else:
            user_form = UserForm()
            cof_form = CofForm()
        # mais on laisse le username en écriture
        cof_form.fields["login_clipper"].widget.attrs["readonly"] = True
        cof_form.fields["is_cof"].widget.attrs["disabled"] = True

    if request:
        account_form = AccountNoTriForm(request.POST)
    else:
        account_form = AccountNoTriForm()

    return {"account_form": account_form, "cof_form": cof_form, "user_form": user_form}


@login_required
@teamkfet_required
def account_create_ajax(request, username=None, login_clipper=None, fullname=None):
    forms = get_account_create_forms(
        request=None, username=username, login_clipper=login_clipper, fullname=fullname
    )
    return render(
        request,
        "kfet/account_create_form.html",
        {
            "account_form": forms["account_form"],
            "cof_form": forms["cof_form"],
            "user_form": forms["user_form"],
        },
    )


# Account - Read


@login_required
def account_read(request, trigramme):
    account = get_object_or_404(Account, trigramme=trigramme)

    # Checking permissions
    if not account.readable or (
        not request.user.has_perm("kfet.is_team") and request.user != account.user
    ):
        raise Http404

    addcosts = (
        OperationGroup.objects.filter(opes__addcost_for=account, opes__canceled_at=None)
        .extra({"date": "date(at)"})
        .values("date")
        .annotate(sum_addcosts=Sum("opes__addcost_amount"))
        .order_by("-date")
    )

    return render(
        request, "kfet/account_read.html", {"account": account, "addcosts": addcosts}
    )


# Account - Update


@teamkfet_required
@kfet_password_auth
def account_update(request, trigramme):
    account = get_object_or_404(Account, trigramme=trigramme)

    # Checking permissions
    if not account.editable:
        # Plus de leak de trigramme !
        return HttpResponseForbidden

    user_info_form = UserInfoForm(instance=account.user)
    account_form = AccountForm(instance=account)
    group_form = UserGroupForm(instance=account.user)
    frozen_form = AccountFrozenForm(instance=account)
    pwd_form = AccountPwdForm()

    if request.method == "POST":
        self_update = request.user == account.user
        account_form = AccountForm(request.POST, instance=account)
        group_form = UserGroupForm(request.POST, instance=account.user)
        frozen_form = AccountFrozenForm(request.POST, instance=account)
        pwd_form = AccountPwdForm(request.POST, account=account)

        forms = []
        warnings = []

        if self_update or request.user.has_perm("kfet.change_account"):
            forms.append(account_form)
        elif account_form.has_changed():
            warnings.append("compte")

        if request.user.has_perm("kfet.manage_perms"):
            forms.append(group_form)
            forms.append(frozen_form)
        elif group_form.has_changed():
            warnings.append("statut d'équipe")

        # Il ne faut pas valider `pwd_form` si elle est inchangée
        if pwd_form.has_changed():
            if self_update or request.user.has_perm("kfet.change_account_password"):
                forms.append(pwd_form)
            else:
                warnings.append("mot de passe")

        # Updating account info
        if forms == []:
            messages.error(
                request,
                "Informations non mises à jour : permission refusée",
                extra_tags="permission-denied",
            )
        else:
            if all(form.is_valid() for form in forms):
                for form in forms:
                    form.save()

                if len(warnings):
                    messages.warning(
                        request,
                        "Permissions insuffisantes pour modifier"
                        " les informations suivantes : {}.".format(", ".join(warnings)),
                    )
                if self_update:
                    messages.success(request, "Vos informations ont été mises à jour !")
                else:
                    messages.success(
                        request,
                        "Informations du compte %s mises à jour" % account.trigramme,
                    )

                return redirect("kfet.account.read", account.trigramme)
            else:
                messages.error(
                    request, "Informations non mises à jour : corrigez les erreurs"
                )

    return render(
        request,
        "kfet/account_update.html",
        {
            "user_info_form": user_info_form,
            "account": account,
            "account_form": account_form,
            "frozen_form": frozen_form,
            "group_form": group_form,
            "pwd_form": pwd_form,
        },
    )


# Account - Delete


class AccountDelete(PermissionRequiredMixin, DeleteView):
    model = Account
    slug_field = "trigramme"
    slug_url_kwarg = "trigramme"
    success_url = reverse_lazy("kfet.account")
    success_message = "Compte supprimé avec succès !"
    permission_required = "kfet.delete_account"

    http_method_names = ["post"]

    def delete(self, request, *args, **kwargs):
        self.object = self.get_object()
        if self.object.balance >= 0.01:
            messages.error(
                request,
                "Impossible de supprimer un compte "
                "avec une balance strictement positive !",
            )
            return redirect("kfet.account.read", self.object.trigramme)

        if self.object.trigramme in [
            "LIQ",
            KFET_GENERIC_TRIGRAMME,
            KFET_DELETED_TRIGRAMME,
            "#13",
        ]:
            messages.error(request, "Impossible de supprimer un trigramme protégé !")
            return redirect("kfet.account.read", self.object.trigramme)

        # SuccessMessageMixin does not work with DeleteView, see :
        # https://code.djangoproject.com/ticket/21926
        messages.success(request, self.success_message)
        return super().delete(request, *args, **kwargs)


class AccountNegativeList(ListView):
    queryset = (
        AccountNegative.objects.select_related("account", "account__cofprofile__user")
        .filter(account__balance__lt=0)
        .exclude(account__trigramme="#13")
    )
    template_name = "kfet/account_negative.html"
    context_object_name = "negatives"

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        balances = (neg.account.balance for neg in self.object_list)
        context["negatives_sum"] = sum(balances)
        return context


# -----
# Checkout views
# -----

# Checkout - General


class CheckoutList(ListView):
    model = Checkout
    template_name = "kfet/checkout.html"
    context_object_name = "checkouts"


# Checkout - Create


@method_decorator(kfet_password_auth, name="dispatch")
class CheckoutCreate(SuccessMessageMixin, CreateView):
    model = Checkout
    template_name = "kfet/checkout_create.html"
    form_class = CheckoutForm
    success_message = "Nouvelle caisse : %(name)s"

    # Surcharge de la validation
    def form_valid(self, form):
        # Checking permission
        if not self.request.user.has_perm("kfet.add_checkout"):
            form.add_error(
                None, ValidationError("Permission refusée", code="permission-denied")
            )
            return self.form_invalid(form)

        # Creating
        form.instance.created_by = self.request.user.profile.account_kfet
        form.save()

        return super().form_valid(form)


# Checkout - Read


class CheckoutRead(DetailView):
    model = Checkout
    template_name = "kfet/checkout_read.html"
    context_object_name = "checkout"

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context["statements"] = context["checkout"].statements.order_by("-at")
        return context


# Checkout - Update


@method_decorator(kfet_password_auth, name="dispatch")
class CheckoutUpdate(SuccessMessageMixin, UpdateView):
    model = Checkout
    template_name = "kfet/checkout_update.html"
    form_class = CheckoutRestrictForm
    success_message = "Informations mises à jour pour la caisse : %(name)s"

    # Surcharge de la validation
    def form_valid(self, form):
        # Checking permission
        if not self.request.user.has_perm("kfet.change_checkout"):
            form.add_error(
                None, ValidationError("Permission refusée", code="permission-denied")
            )
            return self.form_invalid(form)
        # Updating
        return super().form_valid(form)


# -----
# Checkout Statement views
# -----

# Checkout Statement - General


class CheckoutStatementList(ListView):
    model = CheckoutStatement
    queryset = CheckoutStatement.objects.order_by("-at")
    template_name = "kfet/checkoutstatement.html"
    context_object_name = "checkoutstatements"


# Checkout Statement - Create


def getAmountTaken(data):
    return Decimal(
        data.taken_001 * 0.01
        + data.taken_002 * 0.02
        + data.taken_005 * 0.05
        + data.taken_01 * 0.1
        + data.taken_02 * 0.2
        + data.taken_05 * 0.5
        + data.taken_1 * 1
        + data.taken_2 * 2
        + data.taken_5 * 5
        + data.taken_10 * 10
        + data.taken_20 * 20
        + data.taken_50 * 50
        + data.taken_100 * 100
        + data.taken_200 * 200
        + data.taken_500 * 500
        + float(data.taken_cheque)
    )


def getAmountBalance(data):
    return Decimal(
        data["balance_001"] * 0.01
        + data["balance_002"] * 0.02
        + data["balance_005"] * 0.05
        + data["balance_01"] * 0.1
        + data["balance_02"] * 0.2
        + data["balance_05"] * 0.5
        + data["balance_1"] * 1
        + data["balance_2"] * 2
        + data["balance_5"] * 5
        + data["balance_10"] * 10
        + data["balance_20"] * 20
        + data["balance_50"] * 50
        + data["balance_100"] * 100
        + data["balance_200"] * 200
        + data["balance_500"] * 500
    )


@method_decorator(kfet_password_auth, name="dispatch")
class CheckoutStatementCreate(SuccessMessageMixin, CreateView):
    model = CheckoutStatement
    template_name = "kfet/checkoutstatement_create.html"
    form_class = CheckoutStatementCreateForm
    success_message = "Nouveau relevé : %(checkout)s - %(at)s"

    def get_success_url(self):
        return reverse_lazy(
            "kfet.checkout.read", kwargs={"pk": self.kwargs["pk_checkout"]}
        )

    def get_success_message(self, cleaned_data):
        return self.success_message % dict(
            cleaned_data, checkout=self.object.checkout.name, at=self.object.at
        )

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        checkout = Checkout.objects.get(pk=self.kwargs["pk_checkout"])
        context["checkout"] = checkout
        return context

    def form_valid(self, form):
        # Checking permission
        if not self.request.user.has_perm("kfet.add_checkoutstatement"):
            form.add_error(
                None, ValidationError("Permission refusée", code="permission-denied")
            )
            return self.form_invalid(form)
        # Creating
        form.instance.amount_taken = getAmountTaken(form.instance)
        if not form.instance.not_count:
            form.instance.balance_new = getAmountBalance(form.cleaned_data)
        form.instance.checkout_id = self.kwargs["pk_checkout"]
        form.instance.by = self.request.user.profile.account_kfet
        return super().form_valid(form)


@method_decorator(kfet_password_auth, name="dispatch")
class CheckoutStatementUpdate(SuccessMessageMixin, UpdateView):
    model = CheckoutStatement
    template_name = "kfet/checkoutstatement_update.html"
    form_class = CheckoutStatementUpdateForm
    success_message = "Relevé modifié"

    def get_success_url(self):
        return reverse_lazy(
            "kfet.checkout.read", kwargs={"pk": self.kwargs["pk_checkout"]}
        )

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        checkout = Checkout.objects.get(pk=self.kwargs["pk_checkout"])
        context["checkout"] = checkout
        return context

    def form_valid(self, form):
        # Checking permission
        if not self.request.user.has_perm("kfet.change_checkoutstatement"):
            form.add_error(
                None, ValidationError("Permission refusée", code="permission-denied")
            )
            return self.form_invalid(form)
        # Updating
        form.instance.amount_taken = getAmountTaken(form.instance)
        return super().form_valid(form)


# -----
# Category views
# -----


# Category - General
class CategoryList(ListView):
    queryset = ArticleCategory.objects.prefetch_related("articles").order_by("name")
    template_name = "kfet/category.html"
    context_object_name = "categories"


# Category - Update
@method_decorator(kfet_password_auth, name="dispatch")
class CategoryUpdate(SuccessMessageMixin, UpdateView):
    model = ArticleCategory
    template_name = "kfet/category_update.html"
    form_class = CategoryForm
    success_url = reverse_lazy("kfet.category")
    success_message = "Informations mises à jour pour la catégorie : %(name)s"

    # Surcharge de la validation
    def form_valid(self, form):
        # Checking permission
        if not self.request.user.has_perm("kfet.change_articlecategory"):
            form.add_error(
                None, ValidationError("Permission refusée", code="permission-denied")
            )
            return self.form_invalid(form)

        # Updating
        return super().form_valid(form)


# -----
# Article views
# -----


# Article - General
class ArticleList(ListView):
    queryset = (
        Article.objects.select_related("category")
        .prefetch_related(
            Prefetch(
                "inventories",
                queryset=Inventory.objects.order_by("-at"),
                to_attr="inventory",
            )
        )
        .order_by("category__name", "-is_sold", "name")
    )
    template_name = "kfet/article.html"
    context_object_name = "articles"

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        articles = context[self.context_object_name]
        context["nb_articles"] = len(articles)
        context[self.context_object_name] = articles.filter(is_sold=True)
        context["not_sold_articles"] = articles.filter(is_sold=False)
        return context


# Article - Create
@method_decorator(kfet_password_auth, name="dispatch")
class ArticleCreate(SuccessMessageMixin, CreateView):
    model = Article
    template_name = "kfet/article_create.html"
    form_class = ArticleForm
    success_message = "Nouvel item : %(category)s - %(name)s"

    # Surcharge de la validation
    def form_valid(self, form):
        # Checking permission
        if not self.request.user.has_perm("kfet.add_article"):
            form.add_error(
                None, ValidationError("Permission refusée", code="permission-denied")
            )
            return self.form_invalid(form)

        # Save ici pour save le manytomany suppliers
        article = form.save()
        # Save des suppliers déjà existant
        for supplier in form.cleaned_data["suppliers"]:
            SupplierArticle.objects.create(article=article, supplier=supplier)

        # Nouveau supplier
        supplier_new = form.cleaned_data["supplier_new"].strip()
        if supplier_new:
            supplier, created = Supplier.objects.get_or_create(name=supplier_new)
            if created:
                SupplierArticle.objects.create(article=article, supplier=supplier)

        # Inventaire avec stock initial
        inventory = Inventory()
        inventory.by = self.request.user.profile.account_kfet
        inventory.save()
        InventoryArticle.objects.create(
            inventory=inventory,
            article=article,
            stock_old=article.stock,
            stock_new=article.stock,
        )

        # Creating
        return super().form_valid(form)


# Article - Read
class ArticleRead(DetailView):
    model = Article
    template_name = "kfet/article_read.html"
    context_object_name = "article"

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        inventoryarts = (
            InventoryArticle.objects.filter(article=self.object)
            .select_related("inventory")
            .order_by("-inventory__at")
        )
        context["inventoryarts"] = inventoryarts
        supplierarts = (
            SupplierArticle.objects.filter(article=self.object)
            .select_related("supplier")
            .order_by("-at")
        )
        context["supplierarts"] = supplierarts
        return context


# Article - Update
@method_decorator(kfet_password_auth, name="dispatch")
class ArticleUpdate(SuccessMessageMixin, UpdateView):
    model = Article
    template_name = "kfet/article_update.html"
    form_class = ArticleRestrictForm
    success_message = "Informations mises à jour pour l'article : %(name)s"

    # Surcharge de la validation
    def form_valid(self, form):
        # Checking permission
        if not self.request.user.has_perm("kfet.change_article"):
            form.add_error(
                None, ValidationError("Permission refusée", code="permission-denied")
            )
            return self.form_invalid(form)

        # Save ici pour save le manytomany suppliers
        article = form.save()
        # Save des suppliers déjà existant
        for supplier in form.cleaned_data["suppliers"]:
            if supplier not in article.suppliers.all():
                SupplierArticle.objects.create(article=article, supplier=supplier)

        # On vire les suppliers désélectionnés
        for supplier in article.suppliers.all():
            if supplier not in form.cleaned_data["suppliers"]:
                SupplierArticle.objects.filter(
                    article=article, supplier=supplier
                ).delete()

        # Nouveau supplier
        supplier_new = form.cleaned_data["supplier_new"].strip()
        if supplier_new:
            supplier, created = Supplier.objects.get_or_create(name=supplier_new)
            if created:
                SupplierArticle.objects.create(article=article, supplier=supplier)

        # Updating
        return super().form_valid(form)


class ArticleDelete(PermissionRequiredMixin, DeleteView):
    model = Article
    success_url = reverse_lazy("kfet.article")
    success_message = "Article supprimé avec succès !"
    permission_required = "kfet.delete_article"

    def get(self, request, *args, **kwargs):
        return redirect("kfet.article.read", self.kwargs.get(self.pk_url_kwarg))

    def delete(self, request, *args, **kwargs):
        messages.success(request, self.success_message)
        return super().delete(request, *args, **kwargs)


# -----
# K-Psul
# -----


@teamkfet_required
def kpsul(request):
    data = {}
    data["operationgroup_form"] = KPsulOperationGroupForm()
    data["trigramme_form"] = KPsulAccountForm()
    data["checkout_form"] = KPsulCheckoutForm()
    data["operation_formset"] = KPsulOperationFormSet(queryset=Operation.objects.none())
    return render(request, "kfet/kpsul.html", data)


@teamkfet_required
def kpsul_get_settings(request):
    addcost_for = kfet_config.addcost_for
    data = {
        "subvention_cof": kfet_config.subvention_cof,
        "addcost_for": addcost_for and addcost_for.trigramme or "",
        "addcost_amount": kfet_config.addcost_amount,
    }
    return JsonResponse(data)


@teamkfet_required
def account_read_json(request, trigramme):
    account = get_object_or_404(Account, trigramme=trigramme)
    if not account.readable:
        raise Http404
    data = {
        "id": account.pk,
        "name": account.name,
        "email": account.email,
        "is_cof": account.is_cof,
        "promo": account.promo,
        "balance": account.balance,
        "is_frozen": account.is_frozen,
        "departement": account.departement,
        "nickname": account.nickname,
        "trigramme": account.trigramme,
    }
    return JsonResponse(data)


@teamkfet_required
def kpsul_checkout_data(request):
    pk = request.POST.get("pk", 0)
    if not pk:
        pk = 0

    data = (
        Checkout.objects.annotate(
            last_statement_by_first_name=F(
                "statements__by__cofprofile__user__first_name"
            ),
            last_statement_by_last_name=F(
                "statements__by__cofprofile__user__last_name"
            ),
            last_statement_by_trigramme=F("statements__by__trigramme"),
            last_statement_balance=F("statements__balance_new"),
            last_statement_at=F("statements__at"),
        )
        .select_related(
            "statements" "statements__by", "statements__by__cofprofile__user"
        )
        .filter(pk=pk)
        .order_by("statements__at")
        .values(
            "id",
            "name",
            "balance",
            "valid_from",
            "valid_to",
            "last_statement_balance",
            "last_statement_at",
            "last_statement_by_trigramme",
            "last_statement_by_last_name",
            "last_statement_by_first_name",
        )
        .last()
    )
    if data is None:
        raise Http404
    return JsonResponse(data)


@teamkfet_required
@kfet_password_auth
def kpsul_update_addcost(request):
    addcost_form = AddcostForm(request.POST)
    data = {"errors": []}

    if not addcost_form.is_valid():
        for field, errors in addcost_form.errors.items():
            for error in errors:
                data["errors"].append({"code": f"invalid_{field}", "message": error})

        return JsonResponse(data, status=400)

    required_perms = ["kfet.manage_addcosts"]
    if not request.user.has_perms(required_perms):
        data["missing_perms"] = get_missing_perms(required_perms, request.user)
        return JsonResponse(data, status=403)

    trigramme = addcost_form.cleaned_data["trigramme"]
    account = trigramme and Account.objects.get(trigramme=trigramme) or None
    amount = addcost_form.cleaned_data["amount"]

    kfet_config.set(addcost_for=account, addcost_amount=amount)

    data = {
        "addcost": {"for": account and account.trigramme or None, "amount": amount},
        "type": "kpsul",
    }

    channel_layer = get_channel_layer()

    async_to_sync(channel_layer.group_send)("kfet.kpsul", data)
    return JsonResponse(data)


def get_missing_perms(required_perms: List[str], user: User) -> List[str]:
    def get_perm_name(app_label: str, codename: str) -> str:
        return Permission.objects.values_list("name", flat=True).get(
            codename=codename, content_type__app_label=app_label
        )

    missing_perms = [
        get_perm_name(*perm.split("."))
        for perm in required_perms
        if not user.has_perm(perm)
    ]

    return missing_perms


@teamkfet_required
@kfet_password_auth
def kpsul_perform_operations(request):
    # Initializing response data
    data = {"errors": []}

    # Checking operationgroup
    operationgroup_form = KPsulOperationGroupForm(request.POST)
    if not operationgroup_form.is_valid():
        for field in operationgroup_form.errors:
            verbose_field, feminin = (
                ("compte", "") if field == "on_acc" else ("caisse", "e")
            )
            data["errors"].append(
                {
                    "code": f"invalid_{field}",
                    "message": f"Pas de {verbose_field} sélectionné{feminin}",
                }
            )

    # Checking operation_formset
    operation_formset = KPsulOperationFormSet(request.POST)
    if not operation_formset.is_valid():
        data["errors"].append(
            {
                "code": "invalid_formset",
                "message": "Formulaire d'opérations vide ou invalide",
            }
        )

    # Returning BAD REQUEST if errors
    if data["errors"]:
        return JsonResponse(data, status=400)

    # Pre-saving (no commit)
    operationgroup = operationgroup_form.save(commit=False)
    operations = operation_formset.save(commit=False)
    on_acc = operationgroup.on_acc

    # Retrieving COF grant
    cof_grant = kfet_config.subvention_cof
    # Retrieving addcosts data
    addcost_amount = kfet_config.addcost_amount
    addcost_for = kfet_config.addcost_for

    # Initializing vars
    required_perms = set()  # Required perms to perform all operations
    cof_grant_divisor = 1 + cof_grant / 100
    to_addcost_for_balance = 0  # For balance of addcost_for
    to_checkout_balance = 0  # For balance of selected checkout
    to_articles_stocks = defaultdict(lambda: 0)  # For stocks articles
    is_addcost = all((addcost_for, addcost_amount, addcost_for != on_acc))
    need_comment = on_acc.need_comment

    if on_acc.is_frozen:
        data["errors"].append(
            {"code": "frozen_acc", "message": f"Le compte {on_acc.trigramme} est gelé"}
        )

    # Filling data of each operations
    # + operationgroup + calculating other stuffs
    for operation in operations:
        if operation.type == Operation.PURCHASE:
            operation.amount = -operation.article.price * operation.article_nb
            if is_addcost & operation.article.category.has_addcost:
                operation.addcost_for = addcost_for
                operation.addcost_amount = addcost_amount * operation.article_nb
                operation.amount -= operation.addcost_amount
                to_addcost_for_balance += operation.addcost_amount
            if on_acc.is_cash:
                to_checkout_balance += -operation.amount
            if on_acc.is_cof and operation.article.category.has_reduction:
                if is_addcost and operation.article.category.has_addcost:
                    operation.addcost_amount /= cof_grant_divisor
                operation.amount = operation.amount / cof_grant_divisor
            to_articles_stocks[operation.article] -= operation.article_nb
        else:
            if on_acc.is_cash:
                data["errors"].append(
                    {
                        "code": "invalid_liq",
                        "message": (
                            "Impossible de compter autre chose que des achats sur LIQ"
                        ),
                    }
                )
            if operation.type != Operation.EDIT:
                to_checkout_balance += operation.amount
        operationgroup.amount += operation.amount
        if operation.type == Operation.DEPOSIT:
            required_perms.add("kfet.perform_deposit")
        if operation.type == Operation.EDIT:
            required_perms.add("kfet.edit_balance_account")
            need_comment = True
    if on_acc.is_cof:
        to_addcost_for_balance = to_addcost_for_balance / cof_grant_divisor

    (perms, stop) = on_acc.perms_to_perform_operation(amount=operationgroup.amount)
    required_perms |= perms

    if stop:
        data["errors"].append(
            {
                "code": "negative",
                "message": f"Le compte {on_acc.trigramme} a un solde insuffisant.",
            }
        )

    if need_comment:
        operationgroup.comment = operationgroup.comment.strip()
        if not operationgroup.comment:
            data["need_comment"] = True

    if data["errors"] or "need_comment" in data:
        return JsonResponse(data, status=400)

    if not request.user.has_perms(required_perms):
        data["missing_perms"] = get_missing_perms(required_perms, request.user)
        return JsonResponse(data, status=403)

    # If 1 perm is required, filling who perform the operations
    if required_perms:
        operationgroup.valid_by = request.user.profile.account_kfet
    # Filling cof status for statistics
    operationgroup.is_cof = on_acc.is_cof

    # Starting transaction to ensure data consistency
    with transaction.atomic():
        # If not cash account,
        # saving account's balance and adding to Negative if not in
        if not on_acc.is_cash:
            (
                Account.objects.filter(pk=on_acc.pk).update(
                    balance=F("balance") + operationgroup.amount
                )
            )
            on_acc.refresh_from_db()
            on_acc.update_negative()

        # Updating checkout's balance
        if to_checkout_balance:
            Checkout.objects.filter(pk=operationgroup.checkout.pk).update(
                balance=F("balance") + to_checkout_balance
            )

        # Saving addcost_for with new balance if there is one
        if is_addcost and to_addcost_for_balance:
            Account.objects.filter(pk=addcost_for.pk).update(
                balance=F("balance") + to_addcost_for_balance
            )

        # Saving operation group
        operationgroup.save()
        # Filling operationgroup id for each operations and saving
        for operation in operations:
            operation.group = operationgroup
            operation.save()

        # Updating articles stock
        for article in to_articles_stocks:
            Article.objects.filter(pk=article.pk).update(
                stock=F("stock") + to_articles_stocks[article]
            )

    # Websocket data
    websocket_data = {"type": "kpsul"}
    websocket_data["groups"] = [
        {
            "add": True,
            "type": "operation",
            "id": operationgroup.pk,
            "amount": operationgroup.amount,
            "checkout__name": operationgroup.checkout.name,
            "at": operationgroup.at,
            "is_cof": operationgroup.is_cof,
            "comment": operationgroup.comment,
            "valid_by__trigramme": (
                operationgroup.valid_by and operationgroup.valid_by.trigramme or None
            ),
            "on_acc__trigramme": on_acc.trigramme,
            "entries": [],
        }
    ]
    for operation in operations:
        ope_data = {
            "id": operation.pk,
            "type": operation.type,
            "amount": operation.amount,
            "addcost_amount": operation.addcost_amount,
            "addcost_for__trigramme": (
                operation.addcost_for and addcost_for.trigramme or None
            ),
            "article__name": (operation.article and operation.article.name or None),
            "article_nb": operation.article_nb,
            "group_id": operationgroup.pk,
            "canceled_by__trigramme": None,
            "canceled_at": None,
        }
        websocket_data["groups"][0]["entries"].append(ope_data)
    # Need refresh from db cause we used update on queryset
    operationgroup.checkout.refresh_from_db()
    websocket_data["checkouts"] = [
        {"id": operationgroup.checkout.pk, "balance": operationgroup.checkout.balance}
    ]
    websocket_data["articles"] = []
    # Need refresh from db cause we used update on querysets
    articles_pk = [article.pk for article in to_articles_stocks]
    articles = Article.objects.values("id", "stock").filter(pk__in=articles_pk)
    for article in articles:
        websocket_data["articles"].append(
            {"id": article["id"], "stock": article["stock"]}
        )

    channel_layer = get_channel_layer()

    async_to_sync(channel_layer.group_send)("kfet.kpsul", websocket_data)
    return JsonResponse(data)


@teamkfet_required
@kfet_password_auth
def cancel_operations(request):
    # Pour la réponse
    data = {"canceled": [], "warnings": {}, "errors": []}

    # Checking if BAD REQUEST (opes_pk not int or not existing)
    try:
        # Set pour virer les doublons
        opes_post = set(
            map(int, filter(None, request.POST.getlist("operations[]", [])))
        )
    except ValueError:
        data["errors"].append(
            {"code": "invalid_request", "message": "Requête invalide !"}
        )
        return JsonResponse(data, status=400)

    opes_all = Operation.objects.select_related(
        "group", "group__on_acc", "group__on_acc__negative"
    ).filter(pk__in=opes_post)
    opes_pk = [ope.pk for ope in opes_all]
    opes_notexisting = [ope for ope in opes_post if ope not in opes_pk]
    if opes_notexisting:
        data["errors"].append(
            {
                "code": "cancel_missing",
                "message": "Opérations inexistantes : {}".format(
                    ", ".join(map(str, opes_notexisting))
                ),
            }
        )
        return JsonResponse(data, status=400)

    opes_already_canceled = []  # Déjà annulée
    opes = []  # Pas déjà annulée
    required_perms = set()
    cancel_duration = kfet_config.cancel_duration

    # Modifs à faire sur les balances des comptes
    to_accounts_balances = defaultdict(int)
    # ------ sur les montants des groupes d'opé
    to_groups_amounts = defaultdict(int)
    # ------ sur les balances de caisses
    to_checkouts_balances = defaultdict(int)
    # ------ sur les stocks d'articles
    to_articles_stocks = defaultdict(int)

    for ope in opes_all:
        if ope.canceled_at:
            # Opération déjà annulée, va pour un warning en Response
            opes_already_canceled.append(ope.pk)
        else:
            opes.append(ope.pk)
            # Si opé il y a plus de CANCEL_DURATION, permission requise
            if ope.group.at + cancel_duration < timezone.now():
                required_perms.add("kfet.cancel_old_operations")

            # Calcul de toutes modifs à faire en cas de validation

            # Pour les balances de comptes
            if not ope.group.on_acc.is_cash:
                to_accounts_balances[ope.group.on_acc] -= ope.amount
            if ope.addcost_for and ope.addcost_amount:
                to_accounts_balances[ope.addcost_for] -= ope.addcost_amount
            # Pour les groupes d'opés
            to_groups_amounts[ope.group] -= ope.amount

            # Pour les balances de caisses
            # Les balances de caisses dont il y a eu un relevé depuis la date
            # de la commande ne doivent pas être modifiées
            # TODO : Prendre en compte le dernier relevé où la caisse a été
            #        comptée et donc modifier les balance_old (et amount_error)
            #        des relevés suivants.
            #        Note : Dans le cas où un CheckoutStatement est mis à jour
            #        par `.save()`, amount_error est recalculé automatiquement,
            #        ce qui n'est pas le cas en faisant un update sur queryset
            # TODO ? : Maj les balance_old de relevés pour modifier l'erreur
            last_statement = (
                CheckoutStatement.objects.filter(checkout=ope.group.checkout)
                .order_by("at")
                .last()
            )
            if not last_statement or last_statement.at < ope.group.at:
                if ope.is_checkout:
                    if ope.group.on_acc.is_cash:
                        to_checkouts_balances[ope.group.checkout] -= -ope.amount
                    else:
                        to_checkouts_balances[ope.group.checkout] -= ope.amount

            # Pour les stocks d'articles
            # Les stocks d'articles dont il y a eu un inventaire depuis la date
            # de la commande ne doivent pas être modifiés
            # TODO : Prendre en compte le dernier inventaire où le stock a bien
            #        été compté (pas dans le cas d'une livraison).
            #        Note : si InventoryArticle est maj par .save(), stock_error
            #        est recalculé automatiquement
            if ope.article and ope.article_nb:
                last_stock = (
                    InventoryArticle.objects.select_related("inventory")
                    .filter(article=ope.article)
                    .order_by("inventory__at")
                    .last()
                )
                if not last_stock or last_stock.inventory.at < ope.group.at:
                    to_articles_stocks[ope.article] += ope.article_nb

    if not opes:
        data["warnings"]["already_canceled"] = opes_already_canceled
        return JsonResponse(data)

    negative_accounts = []
    # Checking permissions or stop
    for account in to_accounts_balances:
        (perms, stop) = account.perms_to_perform_operation(
            amount=to_accounts_balances[account]
        )
        required_perms |= perms
        if stop:
            negative_accounts.append(account.trigramme)

    if negative_accounts:
        data["errors"].append(
            {
                "code": "negative",
                "message": "Solde insuffisant pour les comptes suivants : {}".format(
                    ", ".join(negative_accounts)
                ),
            }
        )
        return JsonResponse(data, status=400)

    if not request.user.has_perms(required_perms):
        data["missing_perms"] = get_missing_perms(required_perms, request.user)
        return JsonResponse(data, status=403)

    canceled_by = required_perms and request.user.profile.account_kfet or None
    canceled_at = timezone.now()

    with transaction.atomic():
        (
            Operation.objects.filter(pk__in=opes).update(
                canceled_by=canceled_by, canceled_at=canceled_at
            )
        )
        for account in to_accounts_balances:
            (
                Account.objects.filter(pk=account.pk).update(
                    balance=F("balance") + to_accounts_balances[account]
                )
            )
            if not account.is_cash:
                # Should always be true, but we want to be sure
                account.refresh_from_db()
                account.update_negative()
        for checkout in to_checkouts_balances:
            Checkout.objects.filter(pk=checkout.pk).update(
                balance=F("balance") + to_checkouts_balances[checkout]
            )
        for group in to_groups_amounts:
            OperationGroup.objects.filter(pk=group.pk).update(
                amount=F("amount") + to_groups_amounts[group]
            )
        for article in to_articles_stocks:
            Article.objects.filter(pk=article.pk).update(
                stock=F("stock") + to_articles_stocks[article]
            )

    # Need refresh from db cause we used update on querysets.
    # Sort objects by pk to get deterministic responses.
    opegroups_pk = [opegroup.pk for opegroup in to_groups_amounts]
    opegroups = (
        OperationGroup.objects.values("id", "amount", "is_cof")
        .filter(pk__in=opegroups_pk)
        .order_by("pk")
    )
    opes = (
        Operation.objects.values("id", "canceled_at", "canceled_by__trigramme")
        .filter(pk__in=opes)
        .order_by("pk")
    )
    checkouts_pk = [checkout.pk for checkout in to_checkouts_balances]
    checkouts = (
        Checkout.objects.values("id", "balance")
        .filter(pk__in=checkouts_pk)
        .order_by("pk")
    )
    articles_pk = [article.pk for articles in to_articles_stocks]
    articles = Article.objects.values("id", "stock").filter(pk__in=articles_pk)

    # Websocket data
    websocket_data = {"checkouts": [], "articles": [], "type": "kpsul"}
    for checkout in checkouts:
        websocket_data["checkouts"].append(
            {"id": checkout["id"], "balance": checkout["balance"]}
        )
    for article in articles:
        websocket_data["articles"].append(
            {"id": article["id"], "stock": article["stock"]}
        )

    channel_layer = get_channel_layer()

    async_to_sync(channel_layer.group_send)("kfet.kpsul", websocket_data)

    data["canceled"] = list(opes)
    data["opegroups_to_update"] = list(opegroups)
    if opes_already_canceled:
        data["warnings"]["already_canceled"] = opes_already_canceled
    return JsonResponse(data)


def get_history_limit(user) -> Tuple[datetime, datetime]:
    """returns a tuple of 2 dates
    - the earliest date the given user can view history of any account
    - the earliest date the given user can view history of special accounts
       (LIQ and #13)"""
    now = timezone.now()
    if user.has_perm("kfet.access_old_history"):
        return (
            now - settings.KFET_HISTORY_LONG_DATE_LIMIT,
            settings.KFET_HISTORY_NO_DATE_LIMIT,
        )
    if user.has_perm("kfet.is_team"):
        limit = now - settings.KFET_HISTORY_DATE_LIMIT
        return limit, limit
    # should not happen - future earliest date
    future = now + timedelta(days=1)
    return future, future


@login_required
def history_json(request):
    # Récupération des paramètres
    form = FilterHistoryForm(request.GET)

    if not form.is_valid():
        return HttpResponseBadRequest()

    start = form.cleaned_data["start"]
    end = form.cleaned_data["end"]
    account = form.cleaned_data["account"]
    checkout = form.cleaned_data["checkout"]
    transfers_only = form.cleaned_data["transfers_only"]
    opes_only = form.cleaned_data["opes_only"]

    # Construction de la requête (sur les transferts) pour le prefetch

    transfer_queryset_prefetch = Transfer.objects.select_related(
        "from_acc", "to_acc", "canceled_by"
    )

    # Le check sur les comptes est dans le prefetch pour les transferts
    if account:
        transfer_queryset_prefetch = transfer_queryset_prefetch.filter(
            Q(from_acc=account) | Q(to_acc=account)
        )

    if not request.user.has_perm("kfet.is_team"):
        try:
            acc = request.user.profile.account_kfet
            transfer_queryset_prefetch = transfer_queryset_prefetch.filter(
                Q(from_acc=acc) | Q(to_acc=acc)
            )
        except Account.DoesNotExist:
            return JsonResponse({}, status=403)

    transfer_prefetch = Prefetch(
        "transfers", queryset=transfer_queryset_prefetch, to_attr="filtered_transfers"
    )

    # Construction de la requête (sur les opérations) pour le prefetch
    ope_queryset_prefetch = Operation.objects.select_related(
        "article", "canceled_by", "addcost_for"
    )
    ope_prefetch = Prefetch("opes", queryset=ope_queryset_prefetch)

    # Construction de la requête principale
    opegroups = (
        OperationGroup.objects.prefetch_related(ope_prefetch)
        .select_related("on_acc", "valid_by")
        .order_by("at")
    )
    transfergroups = (
        TransferGroup.objects.prefetch_related(transfer_prefetch)
        .select_related("valid_by")
        .order_by("at")
    )

    # limite l'accès à l'historique plus vieux que settings.KFET_HISTORY_DATE_LIMIT
    limit_date = True

    # Application des filtres
    if start:
        opegroups = opegroups.filter(at__gte=start)
        transfergroups = transfergroups.filter(at__gte=start)
    if end:
        opegroups = opegroups.filter(at__lt=end)
        transfergroups = transfergroups.filter(at__lt=end)
    if checkout:
        opegroups = opegroups.filter(checkout=checkout)
        transfergroups = TransferGroup.objects.none()
    if transfers_only:
        opegroups = OperationGroup.objects.none()
    if opes_only:
        transfergroups = TransferGroup.objects.none()
    if account:
        opegroups = opegroups.filter(on_acc=account)
        if account.user == request.user:
            limit_date = False  # pas de limite de date sur son propre historique
    # Un non-membre de l'équipe n'a que accès à son historique
    elif not request.user.has_perm("kfet.is_team"):
        # un non membre de la kfet doit avoir le champ account
        # pré-rempli, cette requête est douteuse
        return JsonResponse({}, status=403)
    if limit_date:
        # limiter l'accès à l'historique ancien pour confidentialité
        earliest_date, earliest_date_no_limit = get_history_limit(request.user)
        if (
            account
            and account.trigramme in settings.KFET_HISTORY_NO_DATE_LIMIT_TRIGRAMMES
        ):
            earliest_date = earliest_date_no_limit
        opegroups = opegroups.filter(at__gte=earliest_date)
        transfergroups = transfergroups.filter(at__gte=earliest_date)

    # Construction de la réponse
    history_groups = []
    for opegroup in opegroups:
        opegroup_dict = {
            "type": "operation",
            "id": opegroup.id,
            "amount": opegroup.amount,
            "at": opegroup.at,
            "checkout_id": opegroup.checkout_id,
            "is_cof": opegroup.is_cof,
            "comment": opegroup.comment,
            "entries": [],
            "on_acc__trigramme": opegroup.on_acc and opegroup.on_acc.trigramme or None,
        }
        if request.user.has_perm("kfet.is_team"):
            opegroup_dict["valid_by__trigramme"] = (
                opegroup.valid_by and opegroup.valid_by.trigramme or None
            )
        for ope in opegroup.opes.all():
            ope_dict = {
                "id": ope.id,
                "type": ope.type,
                "amount": ope.amount,
                "article_nb": ope.article_nb,
                "addcost_amount": ope.addcost_amount,
                "canceled_at": ope.canceled_at,
                "article__name": ope.article and ope.article.name or None,
                "addcost_for__trigramme": ope.addcost_for
                and ope.addcost_for.trigramme
                or None,
            }
            if request.user.has_perm("kfet.is_team"):
                ope_dict["canceled_by__trigramme"] = (
                    ope.canceled_by and ope.canceled_by.trigramme or None
                )
            opegroup_dict["entries"].append(ope_dict)
        history_groups.append(opegroup_dict)
    for transfergroup in transfergroups:
        if transfergroup.filtered_transfers:
            transfergroup_dict = {
                "type": "transfer",
                "id": transfergroup.id,
                "at": transfergroup.at,
                "comment": transfergroup.comment,
                "entries": [],
            }
            if request.user.has_perm("kfet.is_team"):
                transfergroup_dict["valid_by__trigramme"] = (
                    transfergroup.valid_by and transfergroup.valid_by.trigramme or None
                )

            for transfer in transfergroup.filtered_transfers:
                transfer_dict = {
                    "id": transfer.id,
                    "amount": transfer.amount,
                    "canceled_at": transfer.canceled_at,
                    "from_acc": transfer.from_acc.trigramme,
                    "to_acc": transfer.to_acc.trigramme,
                }
                if request.user.has_perm("kfet.is_team"):
                    transfer_dict["canceled_by__trigramme"] = (
                        transfer.canceled_by and transfer.canceled_by.trigramme or None
                    )
                transfergroup_dict["entries"].append(transfer_dict)
            history_groups.append(transfergroup_dict)

    history_groups.sort(key=lambda group: group["at"])

    return JsonResponse({"groups": history_groups})


@teamkfet_required
def kpsul_articles_data(request):
    articles = Article.objects.values(
        "id",
        "name",
        "price",
        "stock",
        "category_id",
        "category__name",
        "category__has_addcost",
        "category__has_reduction",
    ).filter(is_sold=True)
    return JsonResponse({"articles": list(articles)})


@teamkfet_required
def history(request):
    # These limits are only useful for JS datepickers
    # They don't enforce anything and can be bypassed
    # Serious checks are done in history_json
    history_limit, history_no_limit = get_history_limit(request.user)
    history_no_limit_account_ids = Account.objects.filter(
        trigramme__in=settings.KFET_HISTORY_NO_DATE_LIMIT_TRIGRAMMES
    ).values_list("id", flat=True)
    format_date = lambda date: date.strftime("%Y-%m-%d %H:%M")
    data = {
        "filter_form": FilterHistoryForm(),
        "history_limit": format_date(history_limit),
        "history_no_limit_account_ids": history_no_limit_account_ids,
        "history_no_limit": format_date(history_no_limit),
    }
    return render(request, "kfet/history.html", data)


# -----
# Settings views
# -----


class SettingsList(TemplateView):
    template_name = "kfet/settings.html"


config_list = permission_required("kfet.see_config")(SettingsList.as_view())


@method_decorator(kfet_password_auth, name="dispatch")
class SettingsUpdate(SuccessMessageMixin, FormView):
    form_class = KFetConfigForm
    template_name = "kfet/settings_update.html"
    success_message = "Paramètres mis à jour"
    success_url = reverse_lazy("kfet.settings")

    def form_valid(self, form):
        # Checking permission
        if not self.request.user.has_perm("kfet.change_config"):
            form.add_error(
                None, ValidationError("Permission refusée", code="permission-denied")
            )
            return self.form_invalid(form)
        form.save()
        return super().form_valid(form)


config_update = permission_required("kfet.change_config")(SettingsUpdate.as_view())


# -----
# Transfer views
# -----


@method_decorator(teamkfet_required, name="dispatch")
class TransferView(TemplateView):
    template_name = "kfet/transfers.html"


@teamkfet_required
def transfers_create(request):
    transfer_formset = TransferFormSet(queryset=Transfer.objects.none())
    return render(
        request, "kfet/transfers_create.html", {"transfer_formset": transfer_formset}
    )


@teamkfet_required
@kfet_password_auth
def perform_transfers(request):
    data = {"errors": []}

    # Checking transfer_formset
    transfer_formset = TransferFormSet(request.POST)
    try:
        if not transfer_formset.is_valid():
            for form_errors in transfer_formset.errors:
                for field, errors in form_errors.items():
                    if field == "amount":
                        for error in errors:
                            data["errors"].append({"code": "amount", "message": error})
                    else:
                        # C'est compliqué de trouver le compte qui pose problème...
                        acc_error = True

            if acc_error:
                data["errors"].append(
                    {
                        "code": "invalid_acc",
                        "message": "L'un des comptes est invalide ou manquant",
                    }
                )

            return JsonResponse(data, status=400)

    except ValidationError:
        data["errors"].append(
            {"code": "invalid_request", "message": "Requête invalide"}
        )
        return JsonResponse(data, status=400)

    transfers = transfer_formset.save(commit=False)

    # Initializing vars
    required_perms = set(
        ["kfet.add_transfer"]
    )  # Required perms to perform all transfers
    to_accounts_balances = defaultdict(int)  # For balances of accounts

    for transfer in transfers:
        to_accounts_balances[transfer.from_acc] -= transfer.amount
        to_accounts_balances[transfer.to_acc] += transfer.amount

    negative_accounts = []
    # Checking if ok on all accounts
    frozen = set()
    for account in to_accounts_balances:
        if account.is_frozen:
            frozen.add(account.trigramme)

        (perms, stop) = account.perms_to_perform_operation(
            amount=to_accounts_balances[account]
        )
        required_perms |= perms
        if stop:
            negative_accounts.append(account.trigramme)

    if frozen:
        data["errors"].append(
            {
                "code": "frozen",
                "message": "Les comptes suivants sont gelés : {}".format(
                    ", ".join(frozen)
                ),
            }
        )

    if negative_accounts:
        data["errors"].append(
            {
                "code": "negative",
                "message": "Solde insuffisant pour les comptes suivants : {}".format(
                    ", ".join(negative_accounts)
                ),
            }
        )

    if data["errors"]:
        return JsonResponse(data, status=400)

    if not request.user.has_perms(required_perms):
        data["missing_perms"] = get_missing_perms(required_perms, request.user)
        return JsonResponse(data, status=403)

    # Creating transfer group
    transfergroup = TransferGroup()
    if required_perms:
        transfergroup.valid_by = request.user.profile.account_kfet

    comment = request.POST.get("comment", "")
    transfergroup.comment = comment.strip()

    with transaction.atomic():
        # Updating balances accounts
        for account in to_accounts_balances:
            Account.objects.filter(pk=account.pk).update(
                balance=F("balance") + to_accounts_balances[account]
            )
            account.refresh_from_db()
            account.update_negative()

        # Saving transfer group
        transfergroup.save()

        # Saving all transfers with group
        for transfer in transfers:
            transfer.group = transfergroup
            transfer.save()

    return JsonResponse({})


@teamkfet_required
@kfet_password_auth
def cancel_transfers(request):
    # Pour la réponse
    data = {"canceled": [], "warnings": {}, "errors": []}

    # Checking if BAD REQUEST (transfers_pk not int or not existing)
    try:
        # Set pour virer les doublons
        transfers_post = set(
            map(int, filter(None, request.POST.getlist("transfers[]", [])))
        )
    except ValueError:
        data["errors"].append(
            {"code": "invalid_request", "message": "Requête invalide !"}
        )
        return JsonResponse(data, status=400)

    transfers_all = Transfer.objects.select_related(
        "group", "from_acc", "from_acc__negative", "to_acc", "to_acc__negative"
    ).filter(pk__in=transfers_post)
    transfers_pk = [transfer.pk for transfer in transfers_all]
    transfers_notexisting = [
        transfer for transfer in transfers_post if transfer not in transfers_pk
    ]
    if transfers_notexisting:
        data["errors"].append(
            {
                "code": "cancel_missing",
                "message": "Transferts inexistants : {}".format(
                    ", ".join(map(str, transfers_notexisting))
                ),
            }
        )
        return JsonResponse(data, status=400)

    transfers_already_canceled = []  # Déjà annulés
    transfers = []  # Pas déjà annulés
    required_perms = set()
    cancel_duration = kfet_config.cancel_duration

    # Modifs à faire sur les balances des comptes
    to_accounts_balances = defaultdict(int)
    for transfer in transfers_all:
        if transfer.canceled_at:
            # Transfert déjà annulé, va pour un warning en Response
            transfers_already_canceled.append(transfer.pk)
        else:
            transfers.append(transfer.pk)
            # Si transfer il y a plus de CANCEL_DURATION, permission requise
            if transfer.group.at + cancel_duration < timezone.now():
                required_perms.add("kfet.cancel_old_operations")

            # Calcul de toutes modifs à faire en cas de validation

            # Pour les balances de comptes
            to_accounts_balances[transfer.from_acc] += transfer.amount
            to_accounts_balances[transfer.to_acc] += -transfer.amount

    if not transfers:
        data["warnings"]["already_canceled"] = transfers_already_canceled
        return JsonResponse(data)

    negative_accounts = []
    # Checking permissions or stop
    for account in to_accounts_balances:
        (perms, stop) = account.perms_to_perform_operation(
            amount=to_accounts_balances[account]
        )
        required_perms |= perms
        if stop:
            negative_accounts.append(account.trigramme)

    if negative_accounts:
        data["errors"].append(
            {
                "code": "negative",
                "message": "Solde insuffisant pour les comptes suivants : {}".format(
                    ", ".join(negative_accounts)
                ),
            }
        )
        return JsonResponse(data, status=400)

    if not request.user.has_perms(required_perms):
        data["missing_perms"] = get_missing_perms(required_perms, request.user)
        return JsonResponse(data, status=403)

    canceled_by = required_perms and request.user.profile.account_kfet or None
    canceled_at = timezone.now()

    with transaction.atomic():
        (
            Transfer.objects.filter(pk__in=transfers).update(
                canceled_by=canceled_by, canceled_at=canceled_at
            )
        )

        for account in to_accounts_balances:
            Account.objects.filter(pk=account.pk).update(
                balance=F("balance") + to_accounts_balances[account]
            )
            account.refresh_from_db()
            account.update_negative()

    transfers = (
        Transfer.objects.values("id", "canceled_at", "canceled_by__trigramme")
        .filter(pk__in=transfers)
        .order_by("pk")
    )
    data["canceled"] = list(transfers)
    if transfers_already_canceled:
        data["warnings"]["already_canceled"] = transfers_already_canceled
    return JsonResponse(data)


class InventoryList(ListView):
    queryset = (
        Inventory.objects.select_related("by", "order")
        .annotate(nb_articles=Count("articles"))
        .order_by("-at")
    )
    template_name = "kfet/inventory.html"
    context_object_name = "inventories"


@teamkfet_required
@kfet_password_auth
def inventory_create(request):
    articles = Article.objects.select_related("category").order_by(
        "-is_sold", "category__name", "name"
    )
    initial = []
    for article in articles:
        initial.append(
            {
                "is_sold": article.is_sold,
                "article": article.pk,
                "stock_old": article.stock,
                "name": article.name,
                "category": article.category_id,
                "category__name": article.category.name,
                "box_capacity": article.box_capacity or 0,
            }
        )

    cls_formset = formset_factory(form=InventoryArticleForm, extra=0)

    if request.POST:
        formset = cls_formset(request.POST, initial=initial)

        if not request.user.has_perm("kfet.add_inventory"):
            messages.error(
                request, "Permission refusée", extra_tags="permission-denied"
            )
        elif formset.is_valid():
            with transaction.atomic():
                articles = Article.objects.select_for_update()
                inventory = Inventory()
                inventory.by = request.user.profile.account_kfet
                saved = False
                for form in formset:
                    if form.cleaned_data["stock_new"] is not None:
                        if not saved:
                            inventory.save()
                            saved = True

                        article = articles.get(pk=form.cleaned_data["article"].pk)
                        stock_old = article.stock
                        stock_new = form.cleaned_data["stock_new"]
                        InventoryArticle.objects.create(
                            inventory=inventory,
                            article=article,
                            stock_old=stock_old,
                            stock_new=stock_new,
                        )
                        article.stock = stock_new
                        article.save()
                if saved:
                    messages.success(request, "Inventaire créé")
                    return redirect("kfet.inventory")
                messages.warning(request, "Bah alors ? On a rien compté ?")
        else:
            messages.error(request, "Pas marché")
    else:
        formset = cls_formset(initial=initial)

    return render(request, "kfet/inventory_create.html", {"formset": formset})


class InventoryRead(DetailView):
    model = Inventory
    template_name = "kfet/inventory_read.html"
    context_object_name = "inventory"

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        output_field = DecimalField(max_digits=10, decimal_places=2, default=0)
        inventory_articles = (
            InventoryArticle.objects.select_related("article", "article__category")
            .filter(inventory=self.object)
            .annotate(
                amount_error=ExpressionWrapper(
                    F("stock_error") * F("article__price"), output_field=output_field
                )
            )
            .order_by("article__category__name", "article__name")
        )
        context["inventoryarts"] = inventory_articles
        stats = inventory_articles.aggregate(
            new=ExpressionWrapper(
                Sum(F("stock_new") * F("article__price")), output_field=output_field
            ),
            error=Sum("amount_error"),
            old=ExpressionWrapper(
                Sum(F("stock_old") * F("article__price")), output_field=output_field
            ),
        )
        context.update(
            {
                "total_amount_old": stats["old"],
                "total_amount_new": stats["new"],
                "total_amount_error": stats["error"],
            }
        )
        return context


class InventoryDelete(PermissionRequiredMixin, DeleteView):
    model = Inventory
    success_url = reverse_lazy("kfet.inventory")
    success_message = "Inventaire annulé avec succès !"
    permission_required = "kfet.delete_inventory"

    def get(self, request, *args, **kwargs):
        return redirect("kfet.inventory.read", self.kwargs.get(self.pk_url_kwarg))

    def delete(self, request, *args, **kwargs):
        inv = self.get_object()
        # On met à jour les articles dont c'est le dernier inventaire
        # .get() ne marche pas avec OuterRef, donc on utilise .filter() avec [:1]
        update_subquery = InventoryArticle.objects.filter(
            inventory=inv, article=OuterRef("pk")
        ).values("stock_old")[:1]

        Article.objects.annotate(last_env=Max("inventories__at")).filter(
            last_env=inv.at
        ).update(stock=Subquery(update_subquery))

        # On a tout mis à jour, on peut delete (avec un message)
        messages.success(request, self.success_message)
        return super().delete(request, *args, **kwargs)


# -----
# Order views
# -----


class OrderList(ListView):
    queryset = Order.objects.select_related("supplier", "inventory")
    template_name = "kfet/order.html"
    context_object_name = "orders"

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context["suppliers"] = Supplier.objects.order_by("name")
        return context


@teamkfet_required
@kfet_password_auth
def order_create(request, pk):
    supplier = get_object_or_404(Supplier, pk=pk)

    articles = (
        Article.objects.filter(suppliers=supplier.pk)
        .distinct()
        .select_related("category")
        .order_by("-is_sold", "category__name", "name")
    )

    # Force hit to cache
    articles = list(articles)

    sales_q = (
        Operation.objects.select_related("group")
        .filter(article__in=articles, canceled_at=None)
        .values("article")
        .annotate(nb=Sum("article_nb"))
    )
    scale = WeekScale(last=True, n_steps=5, std_chunk=False)
    chunks = scale.chunkify_qs(sales_q, field="group__at")

    sales = [{d["article"]: d["nb"] for d in chunk} for chunk in chunks]

    initial = []

    for article in articles:
        # Get sales for each 5 last weeks
        v_all = [chunk.get(article.pk, 0) for chunk in sales]
        # Take the 3 greatest (eg to avoid 2 weeks of vacations)
        v_3max = heapq.nlargest(3, v_all)
        # Get average and standard deviation
        v_moy = statistics.mean(v_3max)
        v_et = statistics.pstdev(v_3max, v_moy)
        # Expected sales for next week
        v_prev = v_moy + v_et
        # We want to have 1.5 * the expected sales in stock
        # (because sometimes some articles are not delivered)
        c_rec_tot = max(v_prev * 1.5 - article.stock, 0)
        # If ordered quantity is close enough to a level which can led to free
        # boxes, we increase it to this level.
        if article.box_capacity:
            c_rec_temp = c_rec_tot / article.box_capacity
            if c_rec_temp >= 10:
                c_rec = round(c_rec_temp)
            elif c_rec_temp > 5:
                c_rec = 10
            elif c_rec_temp > 2:
                c_rec = 5
            else:
                c_rec = round(c_rec_temp)
        initial.append(
            {
                "article": article.pk,
                "name": article.name,
                "category": article.category_id,
                "category__name": article.category.name,
                "stock": article.stock,
                "box_capacity": article.box_capacity,
                "v_all": v_all,
                "v_moy": round(v_moy),
                "v_et": round(v_et),
                "v_prev": round(v_prev),
                "c_rec": article.box_capacity and c_rec or round(c_rec_tot),
                "is_sold": article.is_sold,
            }
        )

    cls_formset = formset_factory(form=OrderArticleForm, extra=0)

    if request.POST:
        formset = cls_formset(request.POST, initial=initial)

        if not request.user.has_perm("kfet.add_order"):
            messages.error(
                request, "Permission refusée", extra_tags="permission-denied"
            )
        elif formset.is_valid():
            order = Order()
            order.supplier = supplier
            saved = False
            for form in formset:
                if form.cleaned_data["quantity_ordered"] is not None:
                    if not saved:
                        order.save()
                        saved = True

                    article = form.cleaned_data["article"]
                    q_ordered = form.cleaned_data["quantity_ordered"]
                    if article.box_capacity:
                        q_ordered *= article.box_capacity
                    OrderArticle.objects.create(
                        order=order, article=article, quantity_ordered=q_ordered
                    )
            if saved:
                messages.success(request, "Commande créée")
                return redirect("kfet.order.read", order.pk)
            messages.warning(request, "Rien commandé => Pas de commande")
        else:
            messages.error(request, "Corrigez les erreurs")
    else:
        formset = cls_formset(initial=initial)

    scale.label_fmt = "S-{rev_i}"

    return render(
        request,
        "kfet/order_create.html",
        {"supplier": supplier, "formset": formset, "scale": scale},
    )


class OrderRead(DetailView):
    model = Order
    template_name = "kfet/order_read.html"
    context_object_name = "order"

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        orderarticles = (
            OrderArticle.objects.select_related("article", "article__category")
            .filter(order=self.object)
            .order_by("article__category__name", "article__name")
        )
        context["orderarts"] = orderarticles
        mail = (
            "Bonjour,\n\nNous voudrions pour le ##DATE## à la K-Fêt de " "l'ENS Ulm :"
        )
        category = 0
        for orderarticle in orderarticles:
            if category != orderarticle.article.category:
                category = orderarticle.article.category
                mail += "\n"
            nb = orderarticle.quantity_ordered
            box = ""
            if orderarticle.article.box_capacity:
                nb /= orderarticle.article.box_capacity
                if nb >= 2:
                    box = " %ss de" % orderarticle.article.box_type
                else:
                    box = " %s de" % orderarticle.article.box_type
            name = orderarticle.article.name.capitalize()
            mail += "\n- %s%s %s" % (round(nb), box, name)

        mail += (
            "\n\nMerci d'appeler le numéro suivant lorsque les livreurs "
            "sont là : ##TELEPHONE##\nCordialement,\n##PRENOM## ##NOM## "
            ", pour la K-Fêt de l'ENS Ulm"
        )

        context["mail"] = mail
        return context


@teamkfet_required
@kfet_password_auth
def order_to_inventory(request, pk):
    order = get_object_or_404(Order, pk=pk)

    if hasattr(order, "inventory"):
        raise Http404

    supplier_prefetch = Prefetch(
        "article__supplierarticle_set",
        queryset=(
            SupplierArticle.objects.filter(supplier=order.supplier).order_by("-at")
        ),
        to_attr="supplier",
    )

    order_articles = (
        OrderArticle.objects.filter(order=order.pk)
        .select_related("article", "article__category")
        .prefetch_related(supplier_prefetch)
        .order_by("article__category__name", "article__name")
    )

    initial = []
    for order_article in order_articles:
        article = order_article.article
        initial.append(
            {
                "article": article.pk,
                "name": article.name,
                "category": article.category_id,
                "category__name": article.category.name,
                "quantity_ordered": order_article.quantity_ordered,
                "quantity_received": order_article.quantity_ordered,
                "price_HT": article.supplier[0].price_HT,
                "TVA": article.supplier[0].TVA,
                "rights": article.supplier[0].rights,
            }
        )

    cls_formset = formset_factory(OrderArticleToInventoryForm, extra=0)

    if request.method == "POST":
        formset = cls_formset(request.POST, initial=initial)

        if not request.user.has_perm("kfet.order_to_inventory"):
            messages.error(
                request, "Permission refusée", extra_tags="permission-denied"
            )
        elif formset.is_valid():
            with transaction.atomic():
                inventory = Inventory.objects.create(
                    order=order, by=request.user.profile.account_kfet
                )
                new_supplierarticle = []
                new_inventoryarticle = []
                for form in formset:
                    q_received = form.cleaned_data["quantity_received"]
                    article = form.cleaned_data["article"]

                    price_HT = form.cleaned_data["price_HT"]
                    TVA = form.cleaned_data["TVA"]
                    rights = form.cleaned_data["rights"]

                    if any(
                        (
                            form.initial["price_HT"] != price_HT,
                            form.initial["TVA"] != TVA,
                            form.initial["rights"] != rights,
                        )
                    ):
                        new_supplierarticle.append(
                            SupplierArticle(
                                supplier=order.supplier,
                                article=article,
                                price_HT=price_HT,
                                TVA=TVA,
                                rights=rights,
                            )
                        )
                    (
                        OrderArticle.objects.filter(
                            order=order, article=article
                        ).update(quantity_received=q_received)
                    )
                    new_inventoryarticle.append(
                        InventoryArticle(
                            inventory=inventory,
                            article=article,
                            stock_old=article.stock,
                            stock_new=article.stock + q_received,
                        )
                    )
                    article.stock += q_received
                    if q_received > 0:
                        article.is_sold = True
                    article.save()
                SupplierArticle.objects.bulk_create(new_supplierarticle)
                InventoryArticle.objects.bulk_create(new_inventoryarticle)
            messages.success(request, "C'est tout bon !")
            return redirect("kfet.order")
        else:
            messages.error(request, "Corrigez les erreurs")
    else:
        formset = cls_formset(initial=initial)

    return render(
        request, "kfet/order_to_inventory.html", {"formset": formset, "order": order}
    )


@method_decorator(kfet_password_auth, name="dispatch")
class SupplierUpdate(SuccessMessageMixin, UpdateView):
    model = Supplier
    template_name = "kfet/supplier_form.html"
    fields = ["name", "address", "email", "phone", "comment"]
    success_url = reverse_lazy("kfet.order")
    sucess_message = "Données fournisseur mis à jour"

    # Surcharge de la validation
    def form_valid(self, form):
        # Checking permission
        if not self.request.user.has_perm("kfet.change_supplier"):
            form.add_error(
                None, ValidationError("Permission refusée", code="permission-denied")
            )
            return self.form_invalid(form)
        # Updating
        return super().form_valid(form)


# ==========
# Statistics
# ==========


# ---------------
# Vues génériques
# ---------------
# source : docs.djangoproject.com/fr/1.10/topics/class-based-views/mixins/
class JSONResponseMixin:
    """
    A mixin that can be used to render a JSON response.
    """

    def render_to_json_response(self, context, **response_kwargs):
        """
        Returns a JSON response, transforming 'context' to make the payload.
        """
        return JsonResponse(self.get_data(context), **response_kwargs)

    def get_data(self, context):
        """
        Returns an object that will be serialized as JSON by json.dumps().
        """
        # Note: This is *EXTREMELY* naive; in reality, you'll need
        # to do much more complex handling to ensure that arbitrary
        # objects -- such as Django model instances or querysets
        # -- can be serialized as JSON.
        return context


class JSONDetailView(JSONResponseMixin, BaseDetailView):
    """Returns a DetailView that renders a JSON."""

    def render_to_response(self, context):
        return self.render_to_json_response(context)


class SingleResumeStat(JSONDetailView):
    """
    Génère l'interface de sélection pour les statistiques d'un compte/article.
    L'interface est constituée d'une série de boutons, qui récupèrent et graphent
    des statistiques du même type, sur le même objet mais avec des arguments différents.

    Attributs :
        - url_stat : URL où récupérer les statistiques
        - stats : liste de dictionnaires avec les clés suivantes :
            - label : texte du bouton
            - url_params : paramètres GET à rajouter à `url_stat`
            - default : si `True`, graphe à montrer par défaut

    On peut aussi définir `stats` dynamiquement, via la fonction `get_stats`.
    """

    url_stat = None
    stats = []

    def get_stats(self):
        return self.stats

    def get_context_data(self, **kwargs):
        # On n'hérite pas
        context = {}
        stats = []
        # On peut avoir récupéré self.object via pk ou slug
        if self.pk_url_kwarg in self.kwargs:
            url_pk = getattr(self.object, self.pk_url_kwarg)
        else:
            url_pk = getattr(self.object, self.slug_url_kwarg)

        for stat_def in self.get_stats():
            url_params_d = stat_def.get("url_params", {})
            if len(url_params_d) > 0:
                url_params = "?{}".format(urlencode(url_params_d))
            else:
                url_params = ""
            stats.append(
                {
                    "label": stat_def["label"],
                    "url": "{url}{params}".format(
                        url=reverse(self.url_stat, args=[url_pk]), params=url_params
                    ),
                    "default": stat_def.get("default", False),
                }
            )
        context["stats"] = stats
        return context


class UserAccountMixin:
    """
    Mixin qui vérifie que le compte traité par la vue est celui de l'utilisateur·ice
    actuel·le. Dans le cas contraire, renvoie un Http404.
    """

    def get_object(self, *args, **kwargs):
        obj = super().get_object(*args, **kwargs)
        if self.request.user != obj.user:
            raise Http404
        return obj


class ScaleMixin(object):
    """Mixin pour utiliser les outils de `kfet.statistic`."""

    def get_context_data(self, *args, **kwargs):
        # On n'hérite pas
        form = StatScaleForm(self.request.GET, prefix="scale")

        if not form.is_valid():
            raise SuspiciousOperation(
                "Invalid StatScaleForm. Did someone tamper with the GET parameters ?"
            )

        scale_name = form.cleaned_data.pop("name")
        scale_cls = SCALE_DICT.get(scale_name)

        self.scale = scale_cls(**form.cleaned_data)

        return {"labels": self.scale.get_labels()}


# -----------------------
# Evolution Balance perso
# -----------------------


@method_decorator(login_required, name="dispatch")
class AccountStatBalanceList(UserAccountMixin, SingleResumeStat):
    """
    Menu général pour l'historique de balance d'un compte
    """

    model = Account
    slug_url_kwarg = "trigramme"
    slug_field = "trigramme"
    url_stat = "kfet.account.stat.balance"
    stats = [
        {"label": "Tout le temps"},
        {"label": "1 an", "url_params": {"last_days": 365}},
        {"label": "6 mois", "url_params": {"last_days": 183}},
        {"label": "3 mois", "url_params": {"last_days": 90}, "default": True},
        {"label": "30 jours", "url_params": {"last_days": 30}},
    ]


@method_decorator(login_required, name="dispatch")
class AccountStatBalance(UserAccountMixin, JSONDetailView):
    """
    Statistiques (JSON) d'historique de balance d'un compte.
    Prend en compte les opérations et transferts sur la période donnée.
    """

    model = Account
    slug_url_kwarg = "trigramme"
    slug_field = "trigramme"

    def get_changes_list(self, last_days=None, begin_date=None, end_date=None):
        account = self.object

        # prepare filters
        if last_days is not None:
            end_date = timezone.now()
            begin_date = end_date - timezone.timedelta(days=last_days)

        # prepare querysets
        # TODO: retirer les opgroup dont tous les op sont annulées
        opegroups = OperationGroup.objects.filter(on_acc=account)
        transfers = Transfer.objects.filter(canceled_at=None).select_related("group")
        recv_transfers = transfers.filter(to_acc=account)
        sent_transfers = transfers.filter(from_acc=account)

        # apply filters
        if begin_date is not None:
            opegroups = opegroups.filter(at__gte=begin_date)
            recv_transfers = recv_transfers.filter(group__at__gte=begin_date)
            sent_transfers = sent_transfers.filter(group__at__gte=begin_date)

        if end_date is not None:
            opegroups = opegroups.filter(at__lte=end_date)
            recv_transfers = recv_transfers.filter(group__at__lte=end_date)
            sent_transfers = sent_transfers.filter(group__at__lte=end_date)

        # On transforme tout ça en une liste de dictionnaires sous la forme
        # {'at': date,
        #  'amount': changement de la balance (négatif si diminue la balance,
        #                                      positif si l'augmente),
        #  'label': text descriptif,
        #  'balance': état de la balance après l'action (0 pour le moment,
        #                                      sera mis à jour lors d'une
        #                                      autre passe)
        # }

        actions = []

        actions.append(
            {
                "at": (begin_date or account.created_at).isoformat(),
                "amount": 0,
                "balance": 0,
            }
        )
        actions.append(
            {"at": (end_date or timezone.now()).isoformat(), "amount": 0, "balance": 0}
        )

        actions += (
            [
                {"at": ope_grp.at.isoformat(), "amount": ope_grp.amount, "balance": 0}
                for ope_grp in opegroups
            ]
            + [
                {"at": tr.group.at.isoformat(), "amount": tr.amount, "balance": 0}
                for tr in recv_transfers
            ]
            + [
                {"at": tr.group.at.isoformat(), "amount": -tr.amount, "balance": 0}
                for tr in sent_transfers
            ]
        )
        # Maintenant on trie la liste des actions par ordre du plus récent
        # an plus ancien et on met à jour la balance
        if len(actions) > 1:
            actions = sorted(actions, key=lambda k: k["at"], reverse=True)
            actions[0]["balance"] = account.balance
            for i in range(len(actions) - 1):
                actions[i + 1]["balance"] = (
                    actions[i]["balance"] - actions[i + 1]["amount"]
                )
        return actions

    def get_context_data(self, *args, **kwargs):
        context = {}

        form = AccountStatForm(self.request.GET)

        if not form.is_valid():
            raise SuspiciousOperation(
                "Invalid AccountStatForm. Did someone tamper with the GET parameters ?"
            )

        changes = self.get_changes_list(**form.cleaned_data)

        context["charts"] = [
            {"color": "rgb(200, 20, 60)", "label": "Balance", "values": changes}
        ]
        context["is_time_chart"] = True
        if len(changes) > 0:
            context["min_date"] = changes[-1]["at"]
            context["max_date"] = changes[0]["at"]
        # TODO: offset
        return context


# ------------------------
# Consommation personnelle
# ------------------------


@method_decorator(login_required, name="dispatch")
class AccountStatOperationList(UserAccountMixin, SingleResumeStat):
    """
    Menu général pour l'historique de consommation d'un compte
    """

    model = Account
    slug_url_kwarg = "trigramme"
    slug_field = "trigramme"
    url_stat = "kfet.account.stat.operation"

    def get_stats(self):
        scales_def = [
            (
                "Tout le temps",
                MonthScale,
                {"last": True, "begin": self.object.created_at.replace(tzinfo=None)},
                False,
            ),
            ("1 an", MonthScale, {"last": True, "n_steps": 12}, False),
            ("3 mois", WeekScale, {"last": True, "n_steps": 13}, True),
            ("2 semaines", DayScale, {"last": True, "n_steps": 14}, False),
        ]

        return scale_url_params(scales_def)


@method_decorator(login_required, name="dispatch")
class AccountStatOperation(UserAccountMixin, ScaleMixin, JSONDetailView):
    """
    Statistiques (JSON) de consommation (nb d'items achetés) d'un compte.
    """

    model = Account
    slug_url_kwarg = "trigramme"
    slug_field = "trigramme"

    def get_context_data(self, *args, **kwargs):
        context = super().get_context_data(*args, **kwargs)

        operations = (
            Operation.objects.filter(
                type=Operation.PURCHASE, group__on_acc=self.object, canceled_at=None
            )
            .values("article_nb", "group__at")
            .order_by("group__at")
        )
        # On compte les opérations
        nb_ventes = self.scale.chunkify_qs(
            operations, field="group__at", aggregate=Sum("article_nb")
        )

        context["charts"] = [
            {
                "color": "rgb(200, 20, 60)",
                "label": "NB items achetés",
                "values": nb_ventes,
            }
        ]
        return context


# ------------------------
# Article Statistiques Last
# ------------------------


@method_decorator(teamkfet_required, name="dispatch")
class ArticleStatSalesList(SingleResumeStat):
    """
    Menu pour les statistiques de vente d'un article.
    """

    model = Article
    nb_default = 2
    url_stat = "kfet.article.stat.sales"

    def get_stats(self):
        first_conso = (
            Operation.objects.filter(article=self.object)
            .order_by("group__at")
            .values_list("group__at", flat=True)
            .first()
        )
        if first_conso is None:
            # On le crée dans le passé au cas où
            first_conso = timezone.now() - timedelta(seconds=1)
        scales_def = [
            (
                "Tout le temps",
                MonthScale,
                {"last": True, "begin": first_conso.strftime("%Y-%m-%d %H:%M:%S")},
                False,
            ),
            ("1 an", MonthScale, {"last": True, "n_steps": 12}, False),
            ("3 mois", WeekScale, {"last": True, "n_steps": 13}, True),
            ("2 semaines", DayScale, {"last": True, "n_steps": 14}, False),
        ]

        return scale_url_params(scales_def)


@method_decorator(teamkfet_required, name="dispatch")
class ArticleStatSales(ScaleMixin, JSONDetailView):
    """
    Statistiques (JSON) de vente d'un article.
    Sépare LIQ et les comptes K-Fêt, et rajoute le total.
    """

    model = Article
    context_object_name = "article"

    def get_context_data(self, *args, **kwargs):
        context = super().get_context_data(*args, **kwargs)
        scale = self.scale

        all_purchases = (
            Operation.objects.filter(
                type=Operation.PURCHASE, article=self.object, canceled_at=None
            )
            .values("group__at", "article_nb")
            .order_by("group__at")
        )
        cof_accts = all_purchases.filter(group__on_acc__cofprofile__is_cof=True)
        noncof_accts = all_purchases.exclude(group__on_acc__cofprofile__is_cof=True)

        nb_cof = scale.chunkify_qs(
            cof_accts, field="group__at", aggregate=Sum("article_nb")
        )
        nb_noncof = scale.chunkify_qs(
            noncof_accts, field="group__at", aggregate=Sum("article_nb")
        )
        nb_ventes = [n1 + n2 for n1, n2 in zip(nb_cof, nb_noncof)]

        context["charts"] = [
            {
                "color": "rgb(200, 20, 60)",
                "label": "Toutes consommations",
                "values": nb_ventes,
            },
            {"color": "rgb(54, 162, 235)", "label": "Comptes K-Fêt", "values": nb_cof},
            {
                "color": "rgb(255, 205, 86)",
                "label": "LIQ",
                "values": nb_noncof,
            },
        ]
        return context


# ---
# Autocompletion views
# ---


class AccountCreateAutocompleteView(PermissionRequiredMixin, AutocompleteView):
    template_name = "kfet/search_results.html"
    permission_required = "kfet.is_team"
    search_composer = kfet_autocomplete


class AccountSearchAutocompleteView(PermissionRequiredMixin, AutocompleteView):
    permission_required = "kfet.is_team"
    search_composer = kfet_account_only_autocomplete