add tests

club/models.py

@@ -26,6 +26,7 @@ from __future__ import annotations
 from typing import Iterable, Self
 
 from django.conf import settings
+from django.core.cache import cache
 from django.core.exceptions import ObjectDoesNotExist, ValidationError
 from django.core.validators import RegexValidator, validate_email
 from django.db import models, transaction
@@ -186,6 +187,9 @@ class Club(models.Model):
         self.page.save(force_lock=True)
 
     def delete(self, *args, **kwargs) -> tuple[int, dict[str, int]]:
+        # Invalidate the cache of this club and of its memberships
+        for membership in self.members.ongoing().select_related("user"):
+            cache.delete(f"membership_{self.id}_{membership.user.id}")
         self.board_group.delete()
         self.members_group.delete()
         return super().delete(*args, **kwargs)
@@ -206,15 +210,24 @@ class Club(models.Model):
         """Method to see if that object can be edited by the given user."""
         return self.has_rights_in_club(user)
 
-    @cached_property
-    def current_members(self) -> list[Membership]:
-        return self.members.ongoing().select_related("user").order_by("-role")
-
     def get_membership_for(self, user: User) -> Membership | None:
-        """Return the current membership of the given user."""
+        """Return the current membership the given user.
+
+        Note:
+            The result is cached.
+        """
         if user.is_anonymous:
             return None
-        return next((m for m in self.current_members if m.user_id == user.id), None)
+        membership = cache.get(f"membership_{self.id}_{user.id}")
+        if membership == "not_member":
+            return None
+        if membership is None:
+            membership = self.members.filter(user=user, end_date=None).first()
+            if membership is None:
+                cache.set(f"membership_{self.id}_{user.id}", "not_member")
+            else:
+                cache.set(f"membership_{self.id}_{user.id}", membership)
+        return membership
 
     def has_rights_in_club(self, user: User) -> bool:
         return user.is_in_group(pk=self.board_group_id)
@@ -282,20 +295,28 @@ class MembershipQuerySet(models.QuerySet):
         and add them in the club groups they should be in.
 
         Be aware that this adds three db queries :
-
+        one to retrieve the updated memberships,
-        - one to retrieve the updated memberships
+        one to perform group removal and one to perform
-        - one to perform group removal
+        group attribution.
-        - and one to perform group attribution.
         """
         nb_rows = super().update(**kwargs)
         if nb_rows == 0:
-            # if no row was affected, no need to edit club groups
+            # if no row was affected, no need to refresh the cache
             return 0
 
+        cache_memberships = {}
         memberships = set(self.select_related("club"))
         # delete all User-Group relations and recreate the necessary ones
+        # It's more concise to write and more reliable
         Membership._remove_club_groups(memberships)
         Membership._add_club_groups(memberships)
+        for member in memberships:
+            cache_key = f"membership_{member.club_id}_{member.user_id}"
+            if member.end_date is None:
+                cache_memberships[cache_key] = member
+            else:
+                cache_memberships[cache_key] = "not_member"
+        cache.set_many(cache_memberships)
         return nb_rows
 
     def delete(self) -> tuple[int, dict[str, int]]:
@@ -318,6 +339,12 @@ class MembershipQuerySet(models.QuerySet):
         nb_rows, rows_counts = super().delete()
         if nb_rows > 0:
             Membership._remove_club_groups(memberships)
+            cache.set_many(
+                {
+                    f"membership_{m.club_id}_{m.user_id}": "not_member"
+                    for m in memberships
+                }
+            )
         return nb_rows, rows_counts
 
 
@@ -381,6 +408,9 @@ class Membership(models.Model):
         self._remove_club_groups([self])
         if self.end_date is None:
             self._add_club_groups([self])
+            cache.set(f"membership_{self.club_id}_{self.user_id}", self)
+        else:
+            cache.set(f"membership_{self.club_id}_{self.user_id}", "not_member")
 
     def get_absolute_url(self):
         return reverse("club:club_members", kwargs={"club_id": self.club_id})
@@ -401,6 +431,7 @@ class Membership(models.Model):
     def delete(self, *args, **kwargs):
         self._remove_club_groups([self])
         super().delete(*args, **kwargs)
+        cache.delete(f"membership_{self.club_id}_{self.user_id}")
 
     @staticmethod
     def _remove_club_groups(

club/templates/club/club_sellings.jinja

@@ -35,7 +35,7 @@ TODO : rewrite the pagination used in this template an Alpine one
     {% csrf_token %}
     {{ form }}
     <p><input type="submit" value="{% trans %}Show{% endtrans %}" /></p>
-    <p><input type="submit" value="{% trans %}Download as cvs{% endtrans %}" formaction="{{ url('club:sellings_csv', club_id=object.id) }}"/></p>
+    <p><input type="submit" value="{% trans %}Download as csv{% endtrans %}" formaction="{{ url('club:sellings_csv', club_id=object.id) }}"/></p>
   </form>
   <p>
     {% trans %}Quantity: {% endtrans %}{{ total_quantity }} {% trans %}units{% endtrans %}<br/>

club/tests/test_membership.py

@@ -72,6 +72,25 @@ class TestMembershipQuerySet(TestClub):
         expected.sort(key=lambda i: i.id)
         assert members == expected
 
+    def test_update_invalidate_cache(self):
+        """Test that the `update` queryset method properly invalidate cache."""
+        mem_skia = self.simple_board_member.memberships.get(club=self.club)
+        cache.set(f"membership_{mem_skia.club_id}_{mem_skia.user_id}", mem_skia)
+        self.simple_board_member.memberships.update(end_date=localtime(now()).date())
+        assert (
+            cache.get(f"membership_{mem_skia.club_id}_{mem_skia.user_id}")
+            == "not_member"
+        )
+
+        mem_richard = self.richard.memberships.get(club=self.club)
+        cache.set(
+            f"membership_{mem_richard.club_id}_{mem_richard.user_id}", mem_richard
+        )
+        self.richard.memberships.update(role=5)
+        new_mem = self.richard.memberships.get(club=self.club)
+        assert new_mem != "not_member"
+        assert new_mem.role == 5
+
     def test_update_change_club_groups(self):
         """Test that `update` set the user groups accordingly."""
         user = baker.make(User)
@@ -93,6 +112,24 @@ class TestMembershipQuerySet(TestClub):
         assert not user.groups.contains(members_group)
         assert not user.groups.contains(board_group)
 
+    def test_delete_invalidate_cache(self):
+        """Test that the `delete` queryset properly invalidate cache."""
+        mem_skia = self.simple_board_member.memberships.get(club=self.club)
+        mem_comptable = self.president.memberships.get(club=self.club)
+        cache.set(f"membership_{mem_skia.club_id}_{mem_skia.user_id}", mem_skia)
+        cache.set(
+            f"membership_{mem_comptable.club_id}_{mem_comptable.user_id}", mem_comptable
+        )
+
+        # should delete the subscriptions of simple_board_member and president
+        self.club.members.ongoing().board().delete()
+
+        for membership in (mem_skia, mem_comptable):
+            cached_mem = cache.get(
+                f"membership_{membership.club_id}_{membership.user_id}"
+            )
+            assert cached_mem == "not_member"
+
     def test_delete_remove_from_groups(self):
         """Test that `delete` removes from club groups"""
         user = baker.make(User)

core/tests/test_core.py

@@ -22,17 +22,19 @@ from bs4 import BeautifulSoup
 from django.contrib.auth.hashers import make_password
 from django.contrib.auth.models import Permission
 from django.core import mail
+from django.core.cache import cache
 from django.core.exceptions import ValidationError
 from django.core.mail import EmailMessage
 from django.test import Client, RequestFactory, TestCase
 from django.urls import reverse
+from django.utils.timezone import now
 from django.views.generic import View
 from django.views.generic.base import ContextMixin
 from model_bakery import baker
 from pytest_django.asserts import assertInHTML, assertRedirects
 
 from antispam.models import ToxicDomain
-from club.models import Club
+from club.models import Club, Membership
 from core.baker_recipes import subscriber_user
 from core.markdown import markdown
 from core.models import AnonymousUser, Group, Page, User, validate_promo
@@ -434,6 +436,23 @@ class TestUserIsInGroup(TestCase):
         with self.assertNumQueries(0):
             self.public_user.is_in_group(pk=group_not_in.id)
 
+    def test_cache_properly_cleared_membership(self):
+        """Test that when the membership of a user end,
+        the cache is properly invalidated.
+        """
+        membership = baker.make(Membership, club=self.club, user=self.public_user)
+        cache.clear()
+        self.club.get_membership_for(self.public_user)  # this should populate the cache
+        assert membership == cache.get(
+            f"membership_{self.club.id}_{self.public_user.id}"
+        )
+        membership.end_date = now() - timedelta(minutes=5)
+        membership.save()
+        cached_membership = cache.get(
+            f"membership_{self.club.id}_{self.public_user.id}"
+        )
+        assert cached_membership == "not_member"
+
     def test_not_existing_group(self):
         """Test that searching for a not existing group
         returns False.

counter/forms.py

@@ -5,6 +5,7 @@ from datetime import date, datetime, timezone
 
 from dateutil.relativedelta import relativedelta
 from django import forms
+from django.core.validators import MaxValueValidator
 from django.db.models import Exists, OuterRef, Q
 from django.forms import BaseModelFormSet
 from django.utils.timezone import now
@@ -34,6 +35,7 @@ from counter.models import (
     Eticket,
     InvoiceCall,
     Product,
+    ProductFormula,
     Refilling,
     ReturnableProduct,
     ScheduledProductAction,
@@ -316,7 +318,6 @@ class ProductForm(forms.ModelForm):
         }
 
     counters = forms.ModelMultipleChoiceField(
-        help_text=None,
         label=_("Counters"),
         required=False,
         widget=AutoCompleteSelectMultipleCounter,
@@ -327,10 +328,31 @@ class ProductForm(forms.ModelForm):
         super().__init__(*args, instance=instance, **kwargs)
         if self.instance.id:
             self.fields["counters"].initial = self.instance.counters.all()
+            if hasattr(self.instance, "formula"):
+                self.formula_init(self.instance.formula)
         self.action_formset = ScheduledProductActionFormSet(
             *args, product=self.instance, **kwargs
         )
 
+    def formula_init(self, formula: ProductFormula):
+        """Part of the form initialisation specific to formula products."""
+        self.fields["selling_price"].help_text = _(
+            "This product is a formula. "
+            "Its price cannot be greater than the price "
+            "of the products constituting it, which is %(price)s €"
+        ) % {"price": formula.max_selling_price}
+        self.fields["special_selling_price"].help_text = _(
+            "This product is a formula. "
+            "Its special price cannot be greater than the price "
+            "of the products constituting it, which is %(price)s €"
+        ) % {"price": formula.max_special_selling_price}
+        for key, price in (
+            ("selling_price", formula.max_selling_price),
+            ("special_selling_price", formula.max_special_selling_price),
+        ):
+            self.fields[key].widget.attrs["max"] = price
+            self.fields[key].validators.append(MaxValueValidator(price))
+
     def is_valid(self):
         return super().is_valid() and self.action_formset.is_valid()
 
@@ -349,13 +371,47 @@ class ProductForm(forms.ModelForm):
         return product
 
 
+class ProductFormulaForm(forms.ModelForm):
+    class Meta:
+        model = ProductFormula
+        fields = ["products", "result"]
+        widgets = {
+            "products": AutoCompleteSelectMultipleProduct,
+            "result": AutoCompleteSelectProduct,
+        }
+
+    def clean(self):
+        cleaned_data = super().clean()
+        if cleaned_data["result"] in cleaned_data["products"]:
+            self.add_error(
+                None,
+                _(
+                    "The same product cannot be at the same time "
+                    "the result and a part of the formula."
+                ),
+            )
+        prices = [p.selling_price for p in cleaned_data["products"]]
+        special_prices = [p.special_selling_price for p in cleaned_data["products"]]
+        selling_price = cleaned_data["result"].selling_price
+        special_selling_price = cleaned_data["result"].special_selling_price
+        if selling_price > sum(prices) or special_selling_price > sum(special_prices):
+            self.add_error(
+                "result",
+                _(
+                    "The result cannot be more expensive "
+                    "than the total of the other products."
+                ),
+            )
+        return cleaned_data
+
+
 class ReturnableProductForm(forms.ModelForm):
     class Meta:
         model = ReturnableProduct
         fields = ["product", "returned_product", "max_return"]
         widgets = {
-            "product": AutoCompleteSelectProduct(),
+            "product": AutoCompleteSelectProduct,
-            "returned_product": AutoCompleteSelectProduct(),
+            "returned_product": AutoCompleteSelectProduct,
         }
 
     def save(self, commit: bool = True) -> ReturnableProduct:  # noqa FBT

counter/migrations/0036_productformula.py

@@ -0,0 +1,43 @@
+# Generated by Django 5.2.8 on 2025-11-26 11:34
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    dependencies = [("counter", "0035_remove_selling_is_validated_and_more")]
+
+    operations = [
+        migrations.CreateModel(
+            name="ProductFormula",
+            fields=[
+                (
+                    "id",
+                    models.AutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                (
+                    "products",
+                    models.ManyToManyField(
+                        help_text="The products that constitute this formula.",
+                        related_name="formulas",
+                        to="counter.product",
+                        verbose_name="products",
+                    ),
+                ),
+                (
+                    "result",
+                    models.OneToOneField(
+                        help_text="The formula product.",
+                        on_delete=django.db.models.deletion.CASCADE,
+                        to="counter.product",
+                        verbose_name="result product",
+                    ),
+                ),
+            ],
+        ),
+    ]

counter/models.py

@@ -455,6 +455,37 @@ class Product(models.Model):
         return self.selling_price - self.purchase_price
 
 
+class ProductFormula(models.Model):
+    products = models.ManyToManyField(
+        Product,
+        related_name="formulas",
+        verbose_name=_("products"),
+        help_text=_("The products that constitute this formula."),
+    )
+    result = models.OneToOneField(
+        Product,
+        related_name="formula",
+        on_delete=models.CASCADE,
+        verbose_name=_("result product"),
+        help_text=_("The product got with the formula."),
+    )
+
+    def __str__(self):
+        return self.result.name
+
+    @cached_property
+    def max_selling_price(self) -> float:
+        # iterating over all products is less efficient than doing
+        # a simple aggregation, but this method is likely to be used in
+        # coordination with `max_special_selling_price`,
+        # and Django caches the result of the `all` queryset.
+        return sum(p.selling_price for p in self.products.all())
+
+    @cached_property
+    def max_special_selling_price(self) -> float:
+        return sum(p.special_selling_price for p in self.products.all())
+
+
 class CounterQuerySet(models.QuerySet):
     def annotate_has_barman(self, user: User) -> Self:
         """Annotate the queryset with the `user_is_barman` field.

counter/static/bundled/counter/counter-click-index.ts

@@ -1,6 +1,10 @@
 import { AlertMessage } from "#core:utils/alert-message";
 import { BasketItem } from "#counter:counter/basket";
-import type { CounterConfig, ErrorMessage } from "#counter:counter/types";
+import type {
+  CounterConfig,
+  ErrorMessage,
+  ProductFormula,
+} from "#counter:counter/types";
 import type { CounterProductSelect } from "./components/counter-product-select-index.ts";
 
 document.addEventListener("alpine:init", () => {
@@ -47,15 +51,43 @@ document.addEventListener("alpine:init", () => {
 
       this.basket[id] = item;
 
+      this.checkFormulas();
+
       if (this.sumBasket() > this.customerBalance) {
         item.quantity = oldQty;
         if (item.quantity === 0) {
           delete this.basket[id];
         }
-        return gettext("Not enough money");
+        this.alertMessage.display(gettext("Not enough money"), { success: false });
       }
+    },
 
-      return "";
+    checkFormulas() {
+      const products = new Set(
+        Object.keys(this.basket).map((i: string) => Number.parseInt(i)),
+      );
+      const formula: ProductFormula = config.formulas.find((f: ProductFormula) => {
+        return f.products.every((p: number) => products.has(p));
+      });
+      if (formula === undefined) {
+        return;
+      }
+      for (const product of formula.products) {
+        const key = product.toString();
+        this.basket[key].quantity -= 1;
+        if (this.basket[key].quantity <= 0) {
+          this.removeFromBasket(key);
+        }
+      }
+      this.alertMessage.display(
+        interpolate(
+          gettext("Formula %(formula)s applied"),
+          { formula: config.products[formula.result.toString()].name },
+          true,
+        ),
+        { success: true },
+      );
+      this.addToBasket(formula.result.toString(), 1);
     },
 
     getBasketSize() {
@@ -70,14 +102,7 @@ document.addEventListener("alpine:init", () => {
         (acc: number, cur: BasketItem) => acc + cur.sum(),
         0,
       ) as number;
-      return total;
+      return Math.round(total * 100) / 100;
-    },
-
-    addToBasketWithMessage(id: string, quantity: number) {
-      const message = this.addToBasket(id, quantity);
-      if (message.length > 0) {
-        this.alertMessage.display(message, { success: false });
-      }
     },
 
     onRefillingSuccess(event: CustomEvent) {
@@ -116,7 +141,7 @@ document.addEventListener("alpine:init", () => {
           this.finish();
         }
       } else {
-        this.addToBasketWithMessage(code, quantity);
+        this.addToBasket(code, quantity);
       }
       this.codeField.widget.clear();
       this.codeField.widget.focus();

counter/static/bundled/counter/types.d.ts

@@ -7,10 +7,16 @@ export interface InitialFormData {
   errors?: string[];
 }
 
+export interface ProductFormula {
+  result: number;
+  products: number[];
+}
+
 export interface CounterConfig {
   customerBalance: number;
   customerId: number;
   products: Record<string, Product>;
+  formulas: ProductFormula[];
   formInitial: InitialFormData[];
   cancelUrl: string;
 }

counter/static/counter/css/counter-click.scss

@@ -10,12 +10,12 @@
   float: right;
 }
 
-.basket-error-container {
+.basket-message-container {
   position: relative;
   display: block
 }
 
-.basket-error {
+.basket-message {
   z-index: 10; // to get on top of tomselect
   text-align: center;
   position: absolute;

counter/templates/counter/counter_click.jinja

@@ -32,13 +32,11 @@
   <div id="bar-ui" x-data="counter({
                            customerBalance: {{ customer.amount }},
                            products: products,
+                           formulas: formulas,
                            customerId: {{ customer.pk }},
                            formInitial: formInitial,
                            cancelUrl: '{{ cancel_url }}',
                            })">
-    <noscript>
-      <p class="important">Javascript is required for the counter UI.</p>
-    </noscript>
 
     <div id="user_info">
       <h5>{% trans %}Customer{% endtrans %}</h5>
@@ -88,11 +86,12 @@
 
           <form x-cloak method="post" action="" x-ref="basketForm">
 
-            <div class="basket-error-container">
+            <div class="basket-message-container">
               <div
                 x-cloak
-                class="alert alert-red basket-error"
+                class="alert basket-message"
-                x-show="alertMessage.show"
+                :class="alertMessage.success ? 'alert-green' : 'alert-red'"
+                x-show="alertMessage.open"
                 x-transition.duration.500ms
                 x-text="alertMessage.content"
               ></div>
@@ -111,9 +110,9 @@
                     </div>
                   </template>
 
-                  <button @click.prevent="addToBasketWithMessage(item.product.id, -1)">-</button>
+                  <button @click.prevent="addToBasket(item.product.id, -1)">-</button>
                   <span class="quantity" x-text="item.quantity"></span>
-                  <button @click.prevent="addToBasketWithMessage(item.product.id, 1)">+</button>
+                  <button @click.prevent="addToBasket(item.product.id, 1)">+</button>
 
                   <span x-text="item.product.name"></span> :
                   <span x-text="item.sum().toLocaleString(undefined, { minimumFractionDigits: 2 })">€</span>
@@ -213,7 +212,7 @@
                 <h5 class="margin-bottom">{{ category }}</h5>
                 <div class="row gap-2x">
                   {% for product in categories[category] -%}
-                    <button class="card shadow" @click="addToBasketWithMessage('{{ product.id }}', 1)">
+                    <button class="card shadow" @click="addToBasket('{{ product.id }}', 1)">
                       <img
                         class="card-image"
                         alt="image de {{ product.name }}"
@@ -252,6 +251,18 @@
         },
       {%- endfor -%}
     };
+    const formulas = [
+      {%- for formula in formulas -%}
+        {
+          result: {{ formula.result_id }},
+          products: [
+            {%- for product in formula.products.all() -%}
+              {{ product.id }},
+            {%- endfor -%}
+          ]
+        },
+      {%- endfor -%}
+    ];
     const formInitial = [
       {%- for f in form -%}
         {%- if f.cleaned_data -%}

counter/templates/counter/formula_list.jinja

@@ -0,0 +1,35 @@
+{% extends "core/base.jinja" %}
+
+{% block title %}
+  {% trans %}Product formulas{% endtrans %}
+{% endblock %}
+
+{% block additional_css %}
+  <link rel="stylesheet" href="{{ static("core/components/card.scss") }}">
+  <link rel="stylesheet" href="{{ static("counter/css/admin.scss") }}">
+{% endblock %}
+
+{% block content %}
+  <main>
+    <h3 class="margin-bottom">{% trans %}Product formulas{% endtrans %}</h3>
+    <p>
+      <a href="{{ url('counter:product_formula_create') }}" class="btn btn-blue">
+        {% trans %}New formula{% endtrans %}
+        <i class="fa fa-plus"></i>
+      </a>
+    </p>
+    <ul class="product-group">
+      {%- for formula in object_list -%}
+        <li>
+          <a href="{{ url('counter:product_formula_edit', formula_id=formula.id) }}">
+            {{ formula.result.name }}
+          </a>
+          <a href="{{ url('counter:product_formula_delete', formula_id=formula.id) }}">
+            <i class="fa fa-trash delete-action"></i>
+          </a>
+        </li>
+      {%- endfor -%}
+    </ul>
+  </div>
+  </main>
+{% endblock %}

counter/templates/counter/product_list.jinja

@@ -89,7 +89,7 @@
         :disabled="csvLoading"
         :aria-busy="csvLoading"
       >
-        {% trans %}Download as cvs{% endtrans %} <i class="fa fa-file-arrow-down"></i>
+        {% trans %}Download as csv{% endtrans %} <i class="fa fa-file-arrow-down"></i>
       </button>
     </div>
 

counter/tests/test_formula.py

@@ -0,0 +1,59 @@
+from django.test import TestCase
+
+from counter.baker_recipes import product_recipe
+from counter.forms import ProductFormulaForm
+
+
+class TestFormulaForm(TestCase):
+    @classmethod
+    def setUpTestData(cls):
+        cls.products = product_recipe.make(
+            selling_price=iter([1.5, 1, 1]),
+            special_selling_price=iter([1.4, 0.9, 0.9]),
+            _quantity=3,
+            _bulk_create=True,
+        )
+
+    def test_ok(self):
+        form = ProductFormulaForm(
+            data={
+                "result": self.products[0].id,
+                "products": [self.products[1].id, self.products[2].id],
+            }
+        )
+        assert form.is_valid()
+        formula = form.save()
+        assert formula.result == self.products[0]
+        assert set(formula.products.all()) == set(self.products[1:])
+
+    def test_price_invalid(self):
+        self.products[0].selling_price = 2.1
+        self.products[0].save()
+        form = ProductFormulaForm(
+            data={
+                "result": self.products[0].id,
+                "products": [self.products[1].id, self.products[2].id],
+            }
+        )
+        assert not form.is_valid()
+        assert form.errors == {
+            "result": [
+                "Le résultat ne peut pas être plus cher "
+                "que le total des autres produits."
+            ]
+        }
+
+    def test_product_both_in_result_and_products(self):
+        form = ProductFormulaForm(
+            data={
+                "result": self.products[0].id,
+                "products": [self.products[0].id, self.products[1].id],
+            }
+        )
+        assert not form.is_valid()
+        assert form.errors == {
+            "__all__": [
+                "Un même produit ne peut pas être à la fois "
+                "le résultat et un élément de la formule."
+            ]
+        }

counter/tests/test_product.py

@@ -15,8 +15,9 @@ from pytest_django.asserts import assertNumQueries, assertRedirects
 from club.models import Club
 from core.baker_recipes import board_user, subscriber_user
 from core.models import Group, User
+from counter.baker_recipes import product_recipe
 from counter.forms import ProductForm
-from counter.models import Product, ProductType
+from counter.models import Product, ProductFormula, ProductType
 
 
 @pytest.mark.django_db
@@ -93,6 +94,9 @@ class TestCreateProduct(TestCase):
     def setUpTestData(cls):
         cls.product_type = baker.make(ProductType)
         cls.club = baker.make(Club)
+        cls.counter_admin = baker.make(
+            User, groups=[Group.objects.get(id=settings.SITH_GROUP_COUNTER_ADMIN_ID)]
+        )
         cls.data = {
             "name": "foo",
             "description": "bar",
@@ -116,13 +120,36 @@ class TestCreateProduct(TestCase):
         assert instance.name == "foo"
         assert instance.selling_price == 1.0
 
+    def test_form_with_product_from_formula(self):
+        """Test when the edited product is a result of a formula."""
+        self.client.force_login(self.counter_admin)
+        products = product_recipe.make(
+            selling_price=iter([1.5, 1, 1]),
+            special_selling_price=iter([1.4, 0.9, 0.9]),
+            _quantity=3,
+            _bulk_create=True,
+        )
+        baker.make(ProductFormula, result=products[0], products=products[1:])
+
+        data = self.data | {"selling_price": 1.7, "special_selling_price": 1.5}
+        form = ProductForm(data=data, instance=products[0])
+        assert form.is_valid()
+
+        # it shouldn't be possible to give a price higher than the formula's products
+        data = self.data | {"selling_price": 2.1, "special_selling_price": 1.9}
+        form = ProductForm(data=data, instance=products[0])
+        assert not form.is_valid()
+        assert form.errors == {
+            "selling_price": [
+                "Assurez-vous que cette valeur est inférieure ou égale à 2.00."
+            ],
+            "special_selling_price": [
+                "Assurez-vous que cette valeur est inférieure ou égale à 1.80."
+            ],
+        }
+
     def test_view(self):
-        self.client.force_login(
+        self.client.force_login(self.counter_admin)
-            baker.make(
-                User,
-                groups=[Group.objects.get(id=settings.SITH_GROUP_COUNTER_ADMIN_ID)],
-            )
-        )
         url = reverse("counter:new_product")
         response = self.client.get(url)
         assert response.status_code == 200

counter/urls.py

@@ -25,6 +25,10 @@ from counter.views.admin import (
     CounterStatView,
     ProductCreateView,
     ProductEditView,
+    ProductFormulaCreateView,
+    ProductFormulaDeleteView,
+    ProductFormulaEditView,
+    ProductFormulaListView,
     ProductListView,
     ProductTypeCreateView,
     ProductTypeEditView,
@@ -116,6 +120,24 @@ urlpatterns = [
         ProductEditView.as_view(),
         name="product_edit",
     ),
+    path(
+        "admin/formula/", ProductFormulaListView.as_view(), name="product_formula_list"
+    ),
+    path(
+        "admin/formula/new/",
+        ProductFormulaCreateView.as_view(),
+        name="product_formula_create",
+    ),
+    path(
+        "admin/formula/<int:formula_id>/edit",
+        ProductFormulaEditView.as_view(),
+        name="product_formula_edit",
+    ),
+    path(
+        "admin/formula/<int:formula_id>/delete",
+        ProductFormulaDeleteView.as_view(),
+        name="product_formula_delete",
+    ),
     path(
         "admin/product-type/list/",
         ProductTypeListView.as_view(),

counter/views/admin.py

@@ -34,11 +34,13 @@ from counter.forms import (
     CloseCustomerAccountForm,
     CounterEditForm,
     ProductForm,
+    ProductFormulaForm,
     ReturnableProductForm,
 )
 from counter.models import (
     Counter,
     Product,
+    ProductFormula,
     ProductType,
     Refilling,
     ReturnableProduct,
@@ -162,6 +164,49 @@ class ProductEditView(CounterAdminTabsMixin, CounterAdminMixin, UpdateView):
     current_tab = "products"
 
 
+class ProductFormulaListView(CounterAdminTabsMixin, PermissionRequiredMixin, ListView):
+    model = ProductFormula
+    queryset = ProductFormula.objects.select_related("result")
+    template_name = "counter/formula_list.jinja"
+    current_tab = "formulas"
+    permission_required = "counter.view_productformula"
+
+
+class ProductFormulaCreateView(
+    CounterAdminTabsMixin, PermissionRequiredMixin, CreateView
+):
+    model = ProductFormula
+    form_class = ProductFormulaForm
+    pk_url_kwarg = "formula_id"
+    template_name = "core/create.jinja"
+    current_tab = "formulas"
+    success_url = reverse_lazy("counter:product_formula_list")
+    permission_required = "counter.add_productformula"
+
+
+class ProductFormulaEditView(
+    CounterAdminTabsMixin, PermissionRequiredMixin, UpdateView
+):
+    model = ProductFormula
+    form_class = ProductFormulaForm
+    pk_url_kwarg = "formula_id"
+    template_name = "core/edit.jinja"
+    current_tab = "formulas"
+    success_url = reverse_lazy("counter:product_formula_list")
+    permission_required = "counter.change_productformula"
+
+
+class ProductFormulaDeleteView(
+    CounterAdminTabsMixin, PermissionRequiredMixin, DeleteView
+):
+    model = ProductFormula
+    pk_url_kwarg = "formula_id"
+    template_name = "core/delete_confirm.jinja"
+    current_tab = "formulas"
+    success_url = reverse_lazy("counter:product_formula_list")
+    permission_required = "counter.delete_productformula"
+
+
 class ReturnableProductListView(
     CounterAdminTabsMixin, PermissionRequiredMixin, ListView
 ):

counter/views/click.py

@@ -12,6 +12,7 @@
 # OR WITHIN THE LOCAL FILE "LICENSE"
 #
 #
+from collections import defaultdict
 
 from django.core.exceptions import PermissionDenied
 from django.db import transaction
@@ -31,6 +32,7 @@ from counter.forms import BasketForm, RefillForm
 from counter.models import (
     Counter,
     Customer,
+    ProductFormula,
     ReturnableProduct,
     Selling,
 )
@@ -206,12 +208,13 @@ class CounterClick(
         """Add customer to the context."""
         kwargs = super().get_context_data(**kwargs)
         kwargs["products"] = self.products
-        kwargs["categories"] = {}
+        kwargs["formulas"] = ProductFormula.objects.filter(
+            result__in=self.products
+        ).prefetch_related("products")
+        kwargs["categories"] = defaultdict(list)
         for product in kwargs["products"]:
             if product.product_type:
-                kwargs["categories"].setdefault(product.product_type, []).append(
+                kwargs["categories"][product.product_type].append(product)
-                    product
-                )
         kwargs["customer"] = self.customer
         kwargs["cancel_url"] = self.get_success_url()
 

counter/views/mixins.py

@@ -100,6 +100,11 @@ class CounterAdminTabsMixin(TabedViewMixin):
             "slug": "products",
             "name": _("Products"),
         },
+        {
+            "url": reverse_lazy("counter:product_formula_list"),
+            "slug": "formulas",
+            "name": _("Formulas"),
+        },
         {
             "url": reverse_lazy("counter:product_type_list"),
             "slug": "product_types",

locale/fr/LC_MESSAGES/django.po

@@ -388,7 +388,7 @@ msgstr "Montrer"
 
 #: club/templates/club/club_sellings.jinja
 #: counter/templates/counter/product_list.jinja
-msgid "Download as cvs"
+msgid "Download as csv"
 msgstr "Télécharger en CSV"
 
 #: club/templates/club/club_sellings.jinja
@@ -2960,6 +2960,38 @@ msgstr ""
 "Décrivez le produit. Si c'est un click pour un évènement, donnez quelques "
 "détails dessus, comme la date (en incluant l'année)."
 
+#: counter/forms.py
+#, python-format
+msgid ""
+"This product is a formula. Its price cannot be greater than the price of the "
+"products constituting it, which is %(price)s €"
+msgstr ""
+"Ce produit est une formule. Son prix ne peut pas être supérieur au prix des "
+"produits qui la constituent, soit %(price)s €."
+
+#: counter/forms.py
+#, python-format
+msgid ""
+"This product is a formula. Its special price cannot be greater than the "
+"price of the products constituting it, which is %(price)s €"
+msgstr ""
+"Ce produit est une formule. Son prix spécial ne peut pas être supérieur au "
+"prix des produits qui la constituent, soit %(price)s €."
+
+#: counter/forms.py
+msgid ""
+"The same product cannot be at the same time the result and a part of the "
+"formula."
+msgstr ""
+"Un même produit ne peut pas être à la fois le résultat et un élément de la "
+"formule."
+
+#: counter/forms.py
+msgid ""
+"The result cannot be more expensive than the total of the other products."
+msgstr ""
+"Le résultat ne peut pas être plus cher que le total des autres produits."
+
 #: counter/forms.py
 msgid "Refound this account"
 msgstr "Rembourser ce compte"
@@ -3120,6 +3152,18 @@ msgstr "produit"
 msgid "products"
 msgstr "produits"
 
+#: counter/models.py
+msgid "The products that constitute this formula."
+msgstr "Les produits qui constituent cette formule."
+
+#: counter/models.py
+msgid "result product"
+msgstr "produit résultat"
+
+#: counter/models.py
+msgid "The product got with the formula."
+msgstr "Le produit obtenu par la formule."
+
 #: counter/models.py
 msgid "counter type"
 msgstr "type de comptoir"
@@ -3540,6 +3584,14 @@ msgstr "Nouveau eticket"
 msgid "There is no eticket in this website."
 msgstr "Il n'y a pas de eticket sur ce site web."
 
+#: counter/templates/counter/formula_list.jinja
+msgid "Product formulas"
+msgstr "Formules de produits"
+
+#: counter/templates/counter/formula_list.jinja
+msgid "New formula"
+msgstr "Nouvelle formule"
+
 #: counter/templates/counter/fragments/create_student_card.jinja
 msgid "No student card registered."
 msgstr "Aucune carte étudiante enregistrée."
@@ -3879,6 +3931,10 @@ msgstr "Dernières opérations"
 msgid "Counter administration"
 msgstr "Administration des comptoirs"
 
+#: counter/views/mixins.py
+msgid "Formulas"
+msgstr "Formules"
+
 #: counter/views/mixins.py
 msgid "Product types"
 msgstr "Types de produit"

locale/fr/LC_MESSAGES/djangojs.po

@@ -7,7 +7,7 @@
 msgid ""
 msgstr ""
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2025-08-23 15:30+0200\n"
+"POT-Creation-Date: 2025-11-26 15:45+0100\n"
 "PO-Revision-Date: 2024-09-17 11:54+0200\n"
 "Last-Translator: Sli <antoine@bartuccio.fr>\n"
 "Language-Team: AE info <ae.info@utbm.fr>\n"
@@ -206,6 +206,10 @@ msgstr "capture.%s"
 msgid "Not enough money"
 msgstr "Pas assez d'argent"
 
+#: counter/static/bundled/counter/counter-click-index.ts
+msgid "Formula %(formula)s applied"
+msgstr "Formule %(formula)s appliquée"
+
 #: counter/static/bundled/counter/counter-click-index.ts
 msgid "You can't send an empty basket."
 msgstr "Vous ne pouvez pas envoyer un panier vide."
@@ -262,3 +266,9 @@ msgstr "Il n'a pas été possible de modérer l'image"
 #: sas/static/bundled/sas/viewer-index.ts
 msgid "Couldn't delete picture"
 msgstr "Il n'a pas été possible de supprimer l'image"
+
+#: timetable/static/bundled/timetable/generator-index.ts
+msgid ""
+"Wrong timetable format. Make sure you copied if from your student folder."
+msgstr ""
+"Mauvais format d'emploi du temps. Assurez-vous que vous l'avez copié depuis votre dossier étudiants."