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 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.consumers import KPsul
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",
    }

    KPsul.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"]}
        )

    KPsul.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"]}
        )

    KPsul.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