feat: add 1 usdt

src/application/services/payment_quote_service.py

@@ -6,8 +6,10 @@ from src.application.contracts import ICache, ILogger
 from src.application.domain.exceptions import OrderTotalOutOfRangeException, ServiceUnavailableException
 
 
+_MIN_USDT_AMOUNT: Decimal = Decimal('1')
+
 _FEE_TIERS: tuple[tuple[Decimal, Decimal, Decimal, bool, bool], ...] = (
-    (Decimal('0.08'), Decimal('5000'), Decimal('30000'), True, True),
+    (Decimal('0.08'), Decimal('0'), Decimal('30000'), True, True),
     (Decimal('0.06'), Decimal('30000'), Decimal('100000'), False, True),
     (Decimal('0.04'), Decimal('100000'), Decimal('600000'), False, True),
 )
@@ -50,6 +52,11 @@ class PaymentQuoteService:
 
 
     async def get_quote(self, usdt_amount: Decimal) -> PaymentQuote:
+        if usdt_amount < _MIN_USDT_AMOUNT:
+            raise OrderTotalOutOfRangeException(
+                message='Order total is below minimum allowed amount',
+            )
+
         rate_raw = await self._remote_cache.hget('tradex:rub:rate', 'value')
         gas_raw = await self._remote_cache.hget('gwei:eth:last', 'normal_rub')
         self._logger.info(f'Actual market values: rate={rate_raw}, gas={gas_raw}')
@@ -80,25 +87,9 @@ class PaymentQuoteService:
                 break
 
         if chosen_rate is None or service_fee is None or total_price is None:
-            total_if_lowest_fee = (
-                base_rub
-                + (base_rub * Decimal('0.04')).quantize(Decimal('0.01'))
-                + gas_fee
-            ).quantize(Decimal('0.01'))
-            if total_if_lowest_fee > Decimal('600000'):
             raise OrderTotalOutOfRangeException(
                 message='Order total exceeds maximum allowed amount',
             )
-            total_if_highest_fee = (
-                base_rub
-                + (base_rub * Decimal('0.08')).quantize(Decimal('0.01'))
-                + gas_fee
-            ).quantize(Decimal('0.01'))
-            if total_if_highest_fee < Decimal('5000'):
-                raise OrderTotalOutOfRangeException(
-                    message='Order total is below minimum allowed amount',
-                )
-            raise OrderTotalOutOfRangeException()
 
         return PaymentQuote(
             usdt_amount=usdt_amount,