15.02.26

modules/purchase_trade/fee.py

@@ -19,6 +19,7 @@ import logging
 from collections import defaultdict
 from trytond.exceptions import UserWarning, UserError
 from trytond.modules.account.exceptions import PeriodNotFoundError
+from trytond.modules.purchase_trade.finance_tools import InterestCalculator
 
 logger = logging.getLogger(__name__)
 
@@ -56,6 +57,7 @@ class Fee(ModelSQL,ModelView):
         ('lumpsum', 'Lump sum'),
         ('perqt', 'Per qt'),
         ('pprice', '% price'),
+        ('rate', '% Mth'),
         ('pcost', '% cost price'),
         ('ppack', 'Per packing'),
     ], 'Mode', required=True)
@@ -93,6 +95,13 @@ class Fee(ModelSQL,ModelView):
         ('brut', 'Gross'),
         ], string='W. type')
 
+    fee_date = fields.Date("Date")
+
+    @classmethod
+    def default_fee_date(cls):
+        Date = Pool().get('ir.date')
+        return Date.today()
+    
     @classmethod
     def default_qt_state(cls):
         LotQtType = Pool().get('lot.qt.type')
@@ -295,6 +304,7 @@ class Fee(ModelSQL,ModelView):
             return Decimal(lqts[0].lot_quantity)
 
     def get_amount(self,name=None):
+        Date = Pool().get('ir.date')
         sign = Decimal(1)
         if self.price:
             # if self.p_r:
@@ -304,6 +314,37 @@ class Fee(ModelSQL,ModelView):
                 return self.price * sign
             elif self.mode == 'ppack':
                 return round(self.price * self.quantity,2)
+            elif self.mode == 'rate':
+                #take period with estimated trigger date
+                if self.line:
+                    if self.line.purchase.payment_term:
+                        est_date = self.line.purchase.payment_term.get_date()
+                        beg_date = self.fee_date if self.fee_date else Date.today()
+                        factor = InterestCalculator.calculate(
+                            start_date=beg_date,
+                            end_date=est_date,
+                            rate=self.price,
+                            rate_type='annual',
+                            convention='ACT/360',
+                            compounding='simple'
+                        )
+
+                        return round(factor * self.line.unit_price * (self.quantity if self.quantity else 0) * sign,2)
+                if self.sale_line:
+                    if self.sale_line.sale.payment_term:
+                        est_date = self.sale_line.sale.payment_term.get_date()
+                        beg_date = self.fee_date if self.fee_date else Date.today()
+                        factor = InterestCalculator.calculate(
+                            start_date=beg_date,
+                            end_date=est_date,
+                            rate=self.price,
+                            rate_type='annual',
+                            convention='ACT/360',
+                            compounding='simple'
+                        )
+
+                        return round(factor * self.sale_line.unit_price * (self.quantity if self.quantity else 0) * sign,2)
+
             elif self.mode == 'perqt':
                 if self.shipment_in:
                     StockMove = Pool().get('stock.move')

modules/purchase_trade/finance_tools.py

@@ -0,0 +1,141 @@
+from decimal import Decimal, getcontext
+from datetime import date
+from calendar import isleap
+
+getcontext().prec = 28
+
+
+class DayCount:
+
+    @staticmethod
+    def year_fraction(start_date, end_date, convention):
+        if end_date <= start_date:
+            return Decimal('0')
+
+        if convention == 'ACT/360':
+            return Decimal((end_date - start_date).days) / Decimal(360)
+
+        elif convention in ('ACT/365', 'ACT/365F'):
+            return Decimal((end_date - start_date).days) / Decimal(365)
+
+        elif convention == 'ACT/ACT_ISDA':
+            return DayCount._act_act_isda(start_date, end_date)
+
+        elif convention == '30/360_US':
+            return DayCount._30_360_us(start_date, end_date)
+
+        elif convention == '30E/360':
+            return DayCount._30e_360(start_date, end_date)
+
+        elif convention == '30E/360_ISDA':
+            return DayCount._30e_360_isda(start_date, end_date)
+
+        else:
+            raise ValueError(f"Unsupported convention {convention}")
+
+    # ---------- IMPLEMENTATIONS ----------
+
+    @staticmethod
+    def _act_act_isda(start_date, end_date):
+        total = Decimal('0')
+        current = start_date
+
+        while current < end_date:
+            year_end = date(current.year, 12, 31)
+            period_end = min(year_end.replace(day=31) + 
+                             (date(current.year + 1, 1, 1) - year_end),
+                             end_date)
+
+            days_in_period = (period_end - current).days
+            days_in_year = 366 if isleap(current.year) else 365
+
+            total += Decimal(days_in_period) / Decimal(days_in_year)
+            current = period_end
+
+        return total
+
+    @staticmethod
+    def _30_360_us(d1, d2):
+        d1_day = 30 if d1.day == 31 else d1.day
+        if d1.day in (30, 31) and d2.day == 31:
+            d2_day = 30
+        else:
+            d2_day = d2.day
+
+        days = ((d2.year - d1.year) * 360 +
+                (d2.month - d1.month) * 30 +
+                (d2_day - d1_day))
+
+        return Decimal(days) / Decimal(360)
+
+    @staticmethod
+    def _30e_360(d1, d2):
+        d1_day = min(d1.day, 30)
+        d2_day = min(d2.day, 30)
+
+        days = ((d2.year - d1.year) * 360 +
+                (d2.month - d1.month) * 30 +
+                (d2_day - d1_day))
+
+        return Decimal(days) / Decimal(360)
+
+    @staticmethod
+    def _30e_360_isda(d1, d2):
+        d1_day = 30 if d1.day == 31 else d1.day
+        d2_day = 30 if d2.day == 31 else d2.day
+
+        days = ((d2.year - d1.year) * 360 +
+                (d2.month - d1.month) * 30 +
+                (d2_day - d1_day))
+
+        return Decimal(days) / Decimal(360)
+
+
+class InterestCalculator:
+
+    @staticmethod
+    def calculate(
+        start_date,
+        end_date,
+        rate,
+        rate_type='annual',  # 'annual' or 'monthly'
+        convention='ACT/360',
+        compounding='simple',  # simple, annual, monthly, continuous
+    ):
+        """
+        Retourne le facteur d'intérêt (pas le montant).
+        """
+
+        if not start_date or not end_date:
+            return Decimal('0')
+
+        if end_date <= start_date:
+            return Decimal('0')
+
+        rate = Decimal(str(rate))
+
+        # Conversion en taux annuel si besoin
+        if rate_type == 'monthly':
+            annual_rate = rate * Decimal(12)
+        else:
+            annual_rate = rate
+
+        yf = DayCount.year_fraction(start_date, end_date, convention)
+
+        if compounding == 'simple':
+            return annual_rate * yf
+
+        elif compounding == 'annual':
+            return (Decimal(1) + annual_rate) ** yf - Decimal(1)
+
+        elif compounding == 'monthly':
+            monthly_rate = annual_rate / Decimal(12)
+            months = yf * Decimal(12)
+            return (Decimal(1) + monthly_rate) ** months - Decimal(1)
+
+        elif compounding == 'continuous':
+            from math import exp
+            return Decimal(exp(float(annual_rate * yf))) - Decimal(1)
+
+        else:
+            raise ValueError("Unsupported compounding mode")