feat: added shop models

config/settings/base.py

@@ -1,7 +1,7 @@
 import datetime
 from config.settings.environ import *  # noqa
 
-APP_NAME = "TPV"
+APP_NAME = "Shop"
 DESCRIPTION = ""
 VERSION = "0.1.0"
 
@@ -26,6 +26,7 @@ THIRD_PARTY_APPS = [
 ]
 
 PROJECT_APPS = [
+    "shop",
     "tpv",
 ]
 

requirements.test.txt

@@ -1,4 +1,5 @@
 -r requirements.txt
 pytest==7.3.0
+pytest-django==4.8.0
 coverage==7.2.3
 pytest-cov==4.0.0

shop/admin.py

@@ -0,0 +1,51 @@
+from django.contrib import admin
+from shop.models import Product, ProductPrice, OrderLine, Order, Tax
+from unfold.admin import ModelAdmin
+
+
+# Register your models here.
+@admin.register(Product)
+class ProductAdmin(ModelAdmin):
+    search_fields = ("name",)
+    list_display = (
+        "id",
+        "name",
+        "stock",
+        "unit",
+    )
+
+
+@admin.register(ProductPrice)
+class ProductPriceAdmin(ModelAdmin):
+    search_fields = ("product",)
+    autocomplete_fields = ("product",)
+    list_display = (
+        "id",
+        "product",
+        "price",
+        "date",
+    )
+
+
+@admin.register(Tax)
+class TaxAdmin(ModelAdmin):
+    list_display = (
+        "code",
+        "value",
+    )
+
+
+@admin.register(OrderLine)
+class OrderLineAdmin(ModelAdmin):
+    autocomplete_fields = ("product",)
+    list_display = (
+        "id",
+        "product",
+        "price",
+        "quantity",
+    )
+
+
+@admin.register(Order)
+class OrderAdmin(ModelAdmin):
+    list_display = ("id",)

shop/apps.py

@@ -0,0 +1,6 @@
+from django.apps import AppConfig
+
+
+class ShopConfig(AppConfig):
+    default_auto_field = "django.db.models.BigAutoField"
+    name = "shop"

shop/migrations/0001_initial.py

@@ -0,0 +1,250 @@
+# Generated by Django 5.0.3 on 2024-03-24 12:51
+
+import django.db.models.deletion
+import django.utils.timezone
+from decimal import Decimal
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = []
+
+    operations = [
+        migrations.CreateModel(
+            name="OrderLine",
+            fields=[
+                (
+                    "id",
+                    models.BigAutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                (
+                    "quantity",
+                    models.DecimalField(
+                        decimal_places=4,
+                        default=Decimal("1"),
+                        max_digits=13,
+                        verbose_name="Cantidad",
+                    ),
+                ),
+                (
+                    "price",
+                    models.DecimalField(
+                        decimal_places=4, max_digits=13, verbose_name="Precio"
+                    ),
+                ),
+                (
+                    "base_total",
+                    models.DecimalField(
+                        decimal_places=4,
+                        default=Decimal("0"),
+                        max_digits=13,
+                        verbose_name="Total sin impuestos",
+                    ),
+                ),
+                (
+                    "tax_value",
+                    models.PositiveIntegerField(verbose_name="Valor de impuestos"),
+                ),
+                (
+                    "taxes",
+                    models.DecimalField(
+                        decimal_places=4, max_digits=13, verbose_name="Impuestos"
+                    ),
+                ),
+                (
+                    "total",
+                    models.DecimalField(
+                        decimal_places=4, max_digits=13, verbose_name="Total"
+                    ),
+                ),
+            ],
+            options={
+                "verbose_name": "Línea de pedido",
+                "verbose_name_plural": "Líneas de pedido",
+            },
+        ),
+        migrations.CreateModel(
+            name="Product",
+            fields=[
+                (
+                    "id",
+                    models.BigAutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                ("name", models.CharField(max_length=96, verbose_name="Nombre")),
+                (
+                    "description",
+                    models.CharField(
+                        blank=True,
+                        default="",
+                        max_length=1000,
+                        verbose_name="Descripción",
+                    ),
+                ),
+                (
+                    "stock",
+                    models.DecimalField(
+                        decimal_places=4,
+                        default=Decimal("0"),
+                        max_digits=13,
+                        verbose_name="Stock",
+                    ),
+                ),
+                (
+                    "unit",
+                    models.CharField(
+                        choices=[("UNIT", "Unidad"), ("KG", "kg"), ("L", "L")],
+                        default="UNIT",
+                        max_length=6,
+                        verbose_name="Unidad de medida",
+                    ),
+                ),
+            ],
+            options={
+                "verbose_name": "Producto",
+                "verbose_name_plural": "Productos",
+            },
+        ),
+        migrations.CreateModel(
+            name="Tax",
+            fields=[
+                (
+                    "id",
+                    models.BigAutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                (
+                    "code",
+                    models.CharField(
+                        max_length=8, unique=True, verbose_name="Código de impuesto"
+                    ),
+                ),
+                (
+                    "value",
+                    models.PositiveIntegerField(
+                        verbose_name="Valor entero (porcentaje)"
+                    ),
+                ),
+            ],
+            options={
+                "verbose_name": "Impuesto",
+                "verbose_name_plural": "Impuestos",
+            },
+        ),
+        migrations.CreateModel(
+            name="Order",
+            fields=[
+                (
+                    "id",
+                    models.BigAutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                (
+                    "creation_date",
+                    models.DateTimeField(
+                        auto_now_add=True, verbose_name="Fecha de creación"
+                    ),
+                ),
+                (
+                    "last_modification_date",
+                    models.DateTimeField(
+                        auto_now=True, verbose_name="Fecha de última modificación"
+                    ),
+                ),
+                (
+                    "base_total",
+                    models.DecimalField(
+                        decimal_places=2,
+                        default=Decimal("0"),
+                        max_digits=13,
+                        verbose_name="Base imponible",
+                    ),
+                ),
+                (
+                    "total",
+                    models.DecimalField(
+                        decimal_places=2,
+                        default=Decimal("0"),
+                        max_digits=13,
+                        verbose_name="Total",
+                    ),
+                ),
+                (
+                    "lines",
+                    models.ManyToManyField(to="shop.orderline", verbose_name="Líneas"),
+                ),
+            ],
+            options={
+                "verbose_name": "Pedido",
+                "verbose_name_plural": "Pedidos",
+            },
+        ),
+        migrations.AddField(
+            model_name="orderline",
+            name="product",
+            field=models.ForeignKey(
+                on_delete=django.db.models.deletion.CASCADE,
+                to="shop.product",
+                verbose_name="Producto",
+            ),
+        ),
+        migrations.CreateModel(
+            name="ProductPrice",
+            fields=[
+                (
+                    "id",
+                    models.BigAutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                (
+                    "price",
+                    models.DecimalField(
+                        decimal_places=2, max_digits=11, verbose_name="Precio"
+                    ),
+                ),
+                (
+                    "date",
+                    models.DateTimeField(
+                        default=django.utils.timezone.now, verbose_name="Fecha"
+                    ),
+                ),
+                (
+                    "product",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.CASCADE,
+                        related_name="prices",
+                        to="shop.product",
+                        verbose_name="Producto",
+                    ),
+                ),
+            ],
+            options={
+                "verbose_name": "Precio de producto",
+                "verbose_name_plural": "Precio de producto",
+            },
+        ),
+    ]

shop/models.py

@@ -0,0 +1,169 @@
+from decimal import Decimal
+
+from django.db import models
+from django.utils import timezone
+from django.utils.text import gettext_lazy as _
+
+
+class Product(models.Model):
+    class UnitChoices(models.TextChoices):
+        UNIT = "UNIT", _("Unidad")
+        WEIGHT_KG = "KG", _("kg")
+        VOLUME_LITER = "L", _("L")
+
+    name = models.CharField(
+        max_length=96,
+        blank=False,
+        null=False,
+        verbose_name=_("Nombre"),
+    )
+    description = models.CharField(
+        max_length=1000,
+        blank=True,
+        default="",
+        verbose_name=_("Descripción"),
+    )
+    stock = models.DecimalField(
+        max_digits=13,
+        decimal_places=4,
+        default=Decimal("0"),
+        verbose_name=_("Stock"),
+    )
+    unit = models.CharField(
+        max_length=6,
+        choices=UnitChoices.choices,
+        default=UnitChoices.UNIT,
+        verbose_name=_("Unidad de medida"),
+    )
+
+    def __str__(self):
+        return self.name
+
+    class Meta:
+        verbose_name = _("Producto")
+        verbose_name_plural = _("Productos")
+
+
+class ProductPrice(models.Model):
+    price = models.DecimalField(
+        max_digits=11, decimal_places=2, verbose_name=_("Precio")
+    )
+    date = models.DateTimeField(default=timezone.now, verbose_name=_("Fecha"))
+    product = models.ForeignKey(
+        "shop.Product",
+        on_delete=models.CASCADE,
+        verbose_name=_("Producto"),
+        related_name="prices",
+    )
+
+    def __str__(self):
+        return f"{self.price}"
+
+    class Meta:
+        verbose_name = _("Precio de producto")
+        verbose_name_plural = _("Precio de producto")
+
+
+class Tax(models.Model):
+    code = models.CharField(
+        max_length=8, blank=False, unique=True, verbose_name=_("Código de impuesto")
+    )
+    value = models.PositiveIntegerField(
+        null=False, blank=False, verbose_name=_("Valor entero (porcentaje)")
+    )
+
+    def __str__(self):
+        return f"{self.code} - {self.value}%"
+
+    class Meta:
+        verbose_name = _("Impuesto")
+        verbose_name_plural = _("Impuestos")
+
+
+class OrderLine(models.Model):
+    product = models.ForeignKey(
+        "shop.Product",
+        on_delete=models.CASCADE,
+        null=False,
+        blank=False,
+        verbose_name=_("Producto"),
+    )
+    quantity = models.DecimalField(
+        max_digits=13,
+        decimal_places=4,
+        default=Decimal("1"),
+        null=False,
+        blank=False,
+        verbose_name=_("Cantidad"),
+    )
+
+    # Precio del producto en el momento en el que se crea el pedido
+    price = models.DecimalField(
+        max_digits=13, decimal_places=4, verbose_name=_("Precio")
+    )
+
+    # base_total = quantity * price
+    base_total = models.DecimalField(
+        max_digits=13,
+        decimal_places=4,
+        default=Decimal("0"),
+        null=False,
+        blank=False,
+        verbose_name=_("Total sin impuestos"),
+    )
+
+    # Valor entero del impuesto en el momento en el que se crea el pedido
+    tax_value = models.PositiveIntegerField(
+        null=False, blank=False, verbose_name=_("Valor de impuestos")
+    )
+
+    # taxes = price * quantity * (tax_value / 100)
+    taxes = models.DecimalField(
+        max_digits=13, decimal_places=4, verbose_name=_("Impuestos")
+    )
+
+    # total = base_total + taxes
+    total = models.DecimalField(
+        max_digits=13, decimal_places=4, verbose_name=_("Total")
+    )
+
+    def __str__(self):
+        return f"{self.product.name} - {self.quantity} - {self.price}"
+
+    class Meta:
+        verbose_name = _("Línea de pedido")
+        verbose_name_plural = _("Líneas de pedido")
+
+
+class Order(models.Model):
+    lines = models.ManyToManyField("shop.OrderLine", verbose_name=_("Líneas"))
+    creation_date = models.DateTimeField(
+        auto_now_add=True, verbose_name=_("Fecha de creación")
+    )
+    last_modification_date = models.DateTimeField(
+        auto_now=True, verbose_name=_("Fecha de última modificación")
+    )
+
+    base_total = models.DecimalField(
+        default=Decimal("0"),
+        max_digits=13,
+        decimal_places=2,
+        verbose_name=_("Base imponible"),
+    )
+    total = models.DecimalField(
+        default=Decimal("0"), max_digits=13, decimal_places=2, verbose_name=_("Total")
+    )
+
+    def calculate_total_from_lines(self):
+        self.base_total = self.lines.aggregate(base_total=models.Sum("base_total")).get(
+            "base_total"
+        )
+        self.total = self.lines.aggregate(base_total=models.Sum("total")).get(
+            "base_total"
+        )
+
+        self.save()
+
+    class Meta:
+        verbose_name = _("Pedido")
+        verbose_name_plural = _("Pedidos")

shop/tests.py

@@ -0,0 +1,3 @@
+from django.test import TestCase
+
+# Create your tests here.

shop/tests/test_shop_models.py

@@ -0,0 +1,56 @@
+from decimal import Decimal
+from rest_framework.test import APITestCase as TestCase
+from shop.models import Product, ProductPrice, OrderLine, Tax
+from shop.utils import create_order_line_for_product, create_order
+
+
+class ShopModelsTest(TestCase):
+    def setUp(self) -> None:
+        self.tax = Tax.objects.create(
+            code="IVA",
+            value=21,
+        )
+        self.create_products()
+
+    def create_products(self):
+        self.potatoes = Product.objects.create(
+            name="Patatas",
+            stock=Decimal("100.00"),
+            unit=Product.UnitChoices.WEIGHT_KG,
+        )
+        self.gasoline = Product.objects.create(
+            name="Gasolina",
+            stock=Decimal("800.00"),
+            unit=Product.UnitChoices.VOLUME_LITER,
+        )
+        self.usb_c = Product.objects.create(
+            name="Cable USB-C",
+            stock=Decimal("5.00"),
+            unit=Product.UnitChoices.UNIT,
+        )
+
+        ProductPrice.objects.create(product=self.potatoes, price=Decimal("0.80"))
+        ProductPrice.objects.create(product=self.gasoline, price=Decimal("1.15"))
+        ProductPrice.objects.create(product=self.usb_c, price=Decimal("9.95"))
+
+    def test_create_order(self):
+        l1 = create_order_line_for_product(
+            self.potatoes,
+            quantity=Decimal("1.5"),
+            tax=self.tax,
+        )
+        l2 = create_order_line_for_product(
+            self.gasoline,
+            quantity=Decimal("40"),
+            tax=self.tax,
+        )
+        l3 = create_order_line_for_product(
+            self.usb_c,
+            quantity=Decimal("1.00"),
+            tax=self.tax,
+        )
+
+        order = create_order(OrderLine.objects.all())
+
+        assert order.total == l1.total + l2.total + l3.total
+        assert order.base_total == l1.base_total + l2.base_total + l3.base_total

shop/utils.py

@@ -0,0 +1,29 @@
+from decimal import Decimal
+from shop.models import OrderLine, Tax, Product, Order
+from django.db.models import QuerySet
+
+
+def create_order_line_for_product(product: Product, quantity: Decimal, tax: Tax):
+    price = product.prices.last().price
+    base_total = round(price * quantity, 2)
+    taxes = round(base_total * (tax.value / Decimal("100")), 2)
+
+    return OrderLine.objects.create(
+        product=product,
+        quantity=quantity,
+        price=price,
+        base_total=base_total,
+        tax_value=tax.value,
+        taxes=taxes,
+        total=base_total + taxes,
+    )
+
+
+def create_order(lines: QuerySet):
+    order = Order.objects.create()
+
+    for line in lines.all():
+        order.lines.add(line)
+
+    order.calculate_total_from_lines()
+    return order

shop/views.py

@@ -0,0 +1,3 @@
+from django.shortcuts import render
+
+# Create your views here.