Merge pull request 'Fixed function monthly_balance' (#11) from dev into main

Reviewed-on: #11

expenses_manager/expenses/models.py

@@ -68,10 +68,8 @@ class Account(models.Model):
 
     def monthly_balance(self, year=None):
         year = year or date.today().year
-
-        # -------------------------
-        # Previous accumulated balance
-        # -------------------------
+        today = date.today()
+        
         previous_income = (
             self.incomes.filter(date__year__lt=year)
             .aggregate(total=Sum('amount'))['total']
@@ -84,11 +82,7 @@ class Account(models.Model):
             or Decimal('0')
         )
         
-        balance = (self.initial_balance + previous_income - previous_income)
-        
-        # -------------------------
-        # Current year data
-        # -------------------------
+        balance = self.initial_balance + previous_income - previous_expenses
         
         incomes = (
             self.incomes.filter(date__year=year)
@@ -96,30 +90,37 @@ class Account(models.Model):
             .values("month")
             .annotate(total=Sum("amount"))
         )
-
+        
         expenses = (
             self.expenses.filter(date__year=year)
             .annotate(month=ExtractMonth("date"))
             .values("month")
             .annotate(total=Sum("amount"))
         )
-
-        income_map = {i["month"]: i["total"] for i in incomes}
-        expenses_map = {e["month"]: e["total"] for e in expenses}
-
+        
+        income_map = {i["month"]: Decimal(str(i["total"] or 0)) for i in incomes}
+        expenses_map = {e["month"]: Decimal(str(e["total"] or 0)) for e in expenses}
+        
         data = []
-
+        
         for month in range(1, 13):
             balance += income_map.get(month, Decimal("0"))
             balance -= expenses_map.get(month, Decimal("0"))
-
+            
             data.append(
                 {
                     "month": month,
-                    "balance": float(balance),
+                    "balance": float(balance)
                 }
             )
+        
+        if year == today.year:
+            current_month_idx = today.month - 1
+            if 0 <= current_month_idx < len(data):
+                data[current_month_idx]["balance"] = float(self.current_balance())
+        
         return data
+        
 
     def balance_until(self, date):
         incomes_total = self.incomes.filter(date__lte=date).aggregate(