diff --git a/backend/commerce/models.py b/backend/commerce/models.py
index 0ad855c..0c68cef 100644
--- a/backend/commerce/models.py
+++ b/backend/commerce/models.py
@@ -1,7 +1,7 @@
 from django.db import models
 from django.conf import settings
 from django.utils import timezone
-#from django.utils.translation import gettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 from decimal import Decimal
 
 from configuration.models import ShopConfiguration
@@ -140,14 +140,16 @@ class Order(models.Model):
         carrier_price = self.carrier.get_price() if self.carrier else Decimal("0.0")
 
         if self.discount.exists():
-            for discount in self.discount.all():
-                total = Decimal('0.0')
+            discounts = list(self.discount.all())
 
-                # getting all prices from order items (with discount applied if valid)
-                for item in self.items.all():
-                    total = total + item.get_total_price(discount)
+            total = Decimal('0.0')
 
-                return total + carrier_price
+            # getting all prices from order items (with discount applied if valid)
+            for item in self.items.all():
+                total = total + item.get_total_price(discounts)
+
+            return total + carrier_price
+        
         else:
             total = Decimal('0.0')
             # getting all prices from order items (without discount)
@@ -255,8 +257,7 @@ class DiscountCode(models.Model):
     description = models.CharField(max_length=255, blank=True)
     
     # sleva v procentech (0–100)
-    percent = models.DecimalField(max_digits=5, decimal_places=2, help_text="Např. 10.00 = 10% sleva")
-    
+    percent = models.PositiveIntegerField(max_value=100, help_text="Procento sleva 0-100", null=True, blank=True)
     # nebo fixní částka
     amount = models.DecimalField(max_digits=10, decimal_places=2, null=True, blank=True, help_text="Fixní sleva v CZK")
 
@@ -264,9 +265,11 @@ class DiscountCode(models.Model):
     valid_to = models.DateTimeField(null=True, blank=True)
     active = models.BooleanField(default=True)
 
+    #max počet použití
     usage_limit = models.PositiveIntegerField(null=True, blank=True)
     used_count = models.PositiveIntegerField(default=0)
 
+
     specific_products = models.ManyToManyField(
         Product, blank=True, related_name="discount_codes"
     )
@@ -278,11 +281,12 @@ class DiscountCode(models.Model):
         now = timezone.now()
         if not self.active:
             return False
+        
         if self.valid_to and self.valid_to < now:
             return False
+        
         if self.usage_limit and self.used_count >= self.usage_limit:
             return False
-        return True
 
     def __str__(self):
         return f"{self.code} ({self.percent}% or {self.amount} CZK)"
@@ -295,27 +299,84 @@ class OrderItem(models.Model):
     product = models.ForeignKey("products.Product", on_delete=models.PROTECT)
     quantity = models.PositiveIntegerField(default=1)
 
-    def get_total_price(self, discount_object:DiscountCode = None):
-        #FIXME: přidat logiku pro slevové kódy
-        """Calculate total price for this item, applying discount if valid."""
+    def get_total_price(self, discounts: list[DiscountCode] = None):
+        """Vrátí celkovou cenu položky po aplikaci relevantních kupónů.
 
-        if discount_object and discount_object.is_valid():
+        Logika dle ShopConfiguration:
+        - multiplying_coupons=True: procentuální slevy se násobí (sekvenčně)
+          P * (1 - p1) -> výsledné * (1 - p2) ...
+          jinak se použije pouze nejlepší (nejvyšší procento).
+        - addition_of_coupons_amount=True: fixní částky (amount) se sčítají,
+          jinak se použije pouze nejvyšší částka.
+        - Kombinace: nejprve procentuální část, poté odečtení fixní částky.
+        - Sleva se nikdy nesmí dostat pod 0.
+        """
+        base_price = self.product.price * self.quantity
 
-            if (self.product in discount_object.specific_products.all() or self.product.category in discount_object.specific_categories.all()):
-                if discount_object.percent:
-                    return (self.quantity * self.product.price) * (Decimal('1.0') - discount_object.percent / Decimal('100'))
-                
-                elif discount_object.amount:
-                    return (self.quantity * self.product.price) - discount_object.amount
-                
-                else:
-                    raise ValueError("Discount code must have either percent or amount defined.")
-                
-        elif not discount_object:
-            return self.quantity * self.product.price
-        
-        else:
-            raise ValueError("Invalid discount code.")
+        if not discounts:
+            return base_price
+
+
+        config = ShopConfiguration.get_solo()
+
+        #seznám slev
+        applicable_percent_discounts: list[int] = []
+        applicable_amount_discounts: list[Decimal] = []
+
+        #procházení kupónů a určení, které se aplikují
+        for discount in set(discounts):
+            if not discount:
+                continue
+
+            if not discount.is_valid():
+                raise ValueError("Invalid discount code.")
+
+            #defaulting
+            applies = False
+
+            # Určení, zda kupon platí pro produkt/kategorii
+            # prázdný produkt a kategorie = globální kupon
+            if discount.specific_products.exists() or discount.specific_categories.exists():
+                if (self.product in discount.specific_products.all() or self.product.category in discount.specific_categories.all()):
+                    applies = True
+
+            else:
+                applies = True #global
+
+            if not applies:
+                continue
+
+            if discount.percent is not None:
+                applicable_percent_discounts.append(discount.percent)
+            elif discount.amount is not None:
+                applicable_amount_discounts.append(discount.amount)
+
+        final_price = base_price
+
+        # Procentuální slevy
+        if applicable_percent_discounts:
+
+            if config.multiplying_coupons:
+                for pct in applicable_percent_discounts:
+                    factor = (Decimal('1') - (Decimal(pct) / Decimal('100')))
+                    final_price = final_price * factor
+            else:
+                best_pct = max(applicable_percent_discounts)
+                factor = (Decimal('1') - (Decimal(best_pct) / Decimal('100')))
+                final_price = final_price * factor
+
+        # Fixní částky
+        if applicable_amount_discounts:
+            if config.addition_of_coupons_amount:
+                total_amount = sum(applicable_amount_discounts)
+            else:
+                total_amount = max(applicable_amount_discounts)
+            final_price = final_price - total_amount
+
+        if final_price < Decimal('0'):
+            final_price = Decimal('0')
+
+        return final_price.quantize(Decimal('0.01'))
 
     def __str__(self):
         return f"{self.product.name} x{self.quantity}"
\ No newline at end of file
diff --git a/backend/configuration/apps.py b/backend/configuration/apps.py
index eab8aa0..d3265d0 100644
--- a/backend/configuration/apps.py
+++ b/backend/configuration/apps.py
@@ -1,6 +1,21 @@
 from django.apps import AppConfig
-
+from django.db.utils import OperationalError, ProgrammingError
+from .models import ShopConfiguration
 
 class ConfigurationConfig(AppConfig):
     default_auto_field = 'django.db.models.BigAutoField'
     name = 'configuration'
+
+    def ready(self):
+        """Ensure the ShopConfiguration singleton exists at startup.
+
+        Wrapped in broad DB error handling so that commands like
+        makemigrations/migrate don't fail when the table does not yet exist.
+        """
+        try:
+            ShopConfiguration.get_solo()
+            
+        except (OperationalError, ProgrammingError):
+            ShopConfiguration.objects.create()
+
+
diff --git a/backend/configuration/models.py b/backend/configuration/models.py
index c04e12b..61941fd 100644
--- a/backend/configuration/models.py
+++ b/backend/configuration/models.py
@@ -5,10 +5,30 @@ from django.db import models
 class ShopConfiguration(models.Model):
     name = models.CharField(max_length=100, default="Shop name", unique=True)
 
+    logo = models.ImageField(upload_to='shop_logos/', blank=True, null=True)
+    favicon = models.ImageField(upload_to='shop_favicons/', blank=True, null=True)
+
+    contact_email = models.EmailField(max_length=254, blank=True, null=True)
+    contact_phone = models.CharField(max_length=20, blank=True, null=True)
+    contact_address = models.TextField(blank=True, null=True)
+    opening_hours = models.JSONField(blank=True, null=True) #FIXME: vytvoř tvar pro otvírací dobu
+
+    #Social
+    facebook_url = models.URLField(max_length=200, blank=True, null=True)
+    instagram_url = models.URLField(max_length=200, blank=True, null=True)
+    youtube_url = models.URLField(max_length=200, blank=True, null=True)
+    tiktok_url = models.URLField(max_length=200, blank=True, null=True)
+    whatsapp_number = models.CharField(max_length=20, blank=True, null=True)
+
+    #zasilkovna settings
     zasilkovna_shipping_price = models.DecimalField(max_digits=10, decimal_places=2, default=50)
     zasilkovna_address_id = models.CharField(max_length=100, blank=True, null=True, help_text="ID výdejního místa Zásilkovny pro odesílání zásilek")
     free_shipping_over = models.DecimalField(max_digits=10, decimal_places=2, default=2000)
-    
+
+    #coupon settings
+    multiplying_coupons = models.BooleanField(default=True, help_text="Násobení kupónů v objednávce (ano/ne), pokud ne tak se použije pouze nejvyšší slevový kupón")
+    addition_of_coupons_amount = models.BooleanField(default=False, help_text="Sčítání slevových kupónů v objednávce (ano/ne), pokud ne tak se použije pouze nejvyšší slevový kupón")
+
     class CURRENCY(models.TextChoices):
         CZK = "CZK", "Czech Koruna"
         EUR = "EUR", "Euro"