013 add price multiplier

app/domain/price.py

@@ -6,10 +6,12 @@ from decimal import ROUND_HALF_UP, Decimal
 from typing import Protocol
 
 DEFAULT_WEIGHT_ROUND_SCALE = 2
+DEFAULT_PROVIDER_PRICE_MULTIPLIER = Decimal("1")
 MAX_ROUND_SCALE = 6
 DIMENSIONS_ROUND_SCALE = 1
 MIN_WEIGHT_KG = Decimal("0.01")
 MIN_DIMENSION_CM = Decimal("0.1")
+INTEGER_PRICE_QUANTIZER = Decimal("1")
 
 _MISSING = object()
 
@@ -77,12 +79,20 @@ def normalize_delivery_request(
     )
 
 
-def filter_valid_prices(prices: Iterable[object]) -> list[ProviderPrice]:
+def filter_valid_prices(
+    prices: Iterable[object],
+    *,
+    price_multiplier: Decimal = DEFAULT_PROVIDER_PRICE_MULTIPLIER,
+) -> list[ProviderPrice]:
     """Normalize price records and keep only domain-valid entries."""
 
+    normalized_multiplier = _normalize_price_multiplier(price_multiplier)
     valid_prices: list[ProviderPrice] = []
     for price_entry in prices:
-        normalized_price = _normalize_price(price_entry)
+        normalized_price = _normalize_price(
+            price_entry,
+            price_multiplier=normalized_multiplier,
+        )
         if normalized_price is not None:
             valid_prices.append(normalized_price)
     return valid_prices
@@ -94,13 +104,23 @@ def sort_prices_by_price(prices: Iterable[ProviderPrice]) -> list[ProviderPrice]
     return sorted(prices, key=lambda price_entry: price_entry.price)
 
 
-def filter_and_sort_prices(prices: Iterable[object]) -> list[ProviderPrice]:
+def filter_and_sort_prices(
+    prices: Iterable[object],
+    *,
+    price_multiplier: Decimal = DEFAULT_PROVIDER_PRICE_MULTIPLIER,
+) -> list[ProviderPrice]:
     """Apply domain filtering and return prices ordered by value."""
 
-    return sort_prices_by_price(filter_valid_prices(prices))
+    return sort_prices_by_price(
+        filter_valid_prices(prices, price_multiplier=price_multiplier)
+    )
 
 
-def _normalize_price(candidate: object) -> ProviderPrice | None:
+def _normalize_price(
+    candidate: object,
+    *,
+    price_multiplier: Decimal,
+) -> ProviderPrice | None:
     provider = _normalize_text(_get_optional_attr(candidate, "provider"))
     service_name = _normalize_text(_get_optional_attr(candidate, "service_name"))
     currency = _normalize_text(_get_optional_attr(candidate, "currency")).upper()
@@ -117,6 +137,12 @@ def _normalize_price(candidate: object) -> ProviderPrice | None:
     price = _try_to_decimal(price_raw)
     if price is None or not price.is_finite() or price <= 0:
         return None
+    adjusted_price = _apply_price_multiplier_and_round(
+        price,
+        price_multiplier=price_multiplier,
+    )
+    if adjusted_price is None:
+        return None
 
     min_days = _try_to_int(min_days_raw)
     max_days = _try_to_int(max_days_raw)
@@ -129,7 +155,7 @@ def _normalize_price(candidate: object) -> ProviderPrice | None:
     return ProviderPrice(
         provider=provider,
         service_name=service_name,
-        price=price,
+        price=adjusted_price,
         currency=currency,
         delivery_days_min=min_days,
         delivery_days_max=max_days,
@@ -192,6 +218,27 @@ def _round_half_up(value: Decimal, scale: int) -> Decimal:
     return value.quantize(quantizer, rounding=ROUND_HALF_UP)
 
 
+def _normalize_price_multiplier(value: Decimal) -> Decimal:
+    multiplier = _try_to_decimal(value)
+    if multiplier is None or not multiplier.is_finite() or multiplier <= 0:
+        raise ValueError(f"Price multiplier must be a positive finite Decimal: {value!r}")
+    return multiplier
+
+
+def _apply_price_multiplier_and_round(
+    price: Decimal,
+    *,
+    price_multiplier: Decimal,
+) -> Decimal | None:
+    adjusted_price = (price * price_multiplier).quantize(
+        INTEGER_PRICE_QUANTIZER,
+        rounding=ROUND_HALF_UP,
+    )
+    if not adjusted_price.is_finite() or adjusted_price <= 0:
+        return None
+    return adjusted_price
+
+
 def _to_decimal(value: object) -> Decimal:
     converted = _try_to_decimal(value)
     if converted is None: