feat: price home delivery with Jadlog

FREIGHT_ADAPTER=jadlog prices "Receber em casa" through Jadlog's Simulador
de Frete from the order's billed metres and value, adding production days
to Jadlog's delivery time. The package weight is a base plus a weight per
metre from the client, with no default: the adapter refuses to start
without it and without the credentials. The cart re-quotes when the package
changes, and approval quotes again from the server-priced items. The
production stack takes the Jadlog settings, so the read-only probe runs
from the worker's console.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

app/jadlog.py

@@ -7,8 +7,10 @@ unlike Tiny it can be tried on the real account as often as needed.
 
 The client's contract: origin CEP 14402-310, service .PACKAGE (modalidade 3),
 home delivery. Jadlog prices by weight in kg and expects the larger of the
-real and the cubed weight; the weight per metre of film is still to come from
-the client, so nothing here decides it.
+real and the cubed weight. The package weight comes from the client (a base
+plus a weight per billed metre) and has no default: FREIGHT_ADAPTER=jadlog
+refuses to start without it, so a guessed weight never prices a customer's
+freight.
 """
 import os
 from decimal import ROUND_HALF_UP, Decimal
@@ -18,6 +20,8 @@ import httpx
 QUOTE_URL = 'https://www.jadlog.com.br/embarcador/api/frete/valor'
 PACKAGE = 3
 ORIGIN = '14402310'
+SERVICE = 'jadlog'
+WEIGHT_SETTINGS = ('JADLOG_PESO_BASE_KG', 'JADLOG_PESO_POR_METRO_KG')
 
 
 class JadlogError(Exception):
@@ -72,3 +76,42 @@ class JadlogQuotes:
         total = Decimal(str(items[0]['vltotal']))
         return {'total_cents': int((total * 100).quantize(Decimal('1'), ROUND_HALF_UP)),
                 'days': items[0].get('prazo'), 'raw': items[0]}
+
+
+def required_settings():
+    return ('JADLOG_TOKEN', 'JADLOG_CNPJ') + WEIGHT_SETTINGS
+
+
+class JadlogFreight:
+    """The Site's delivery option: Jadlog's price for the order's package."""
+    name = 'jadlog'
+
+    def __init__(self, quotes=None):
+        self.quotes = quotes or JadlogQuotes()
+        self.base_kg = Decimal(os.environ['JADLOG_PESO_BASE_KG'])
+        self.per_metre_kg = Decimal(os.environ['JADLOG_PESO_POR_METRO_KG'])
+        # Jadlog's time counts from collection; the order is printed first.
+        self.production_days = int(os.environ.get('FREIGHT_PRODUCTION_DAYS') or 0)
+        if self.base_kg < 0 or self.per_metre_kg <= 0 or self.production_days < 0:
+            raise RuntimeError('Jadlog package weight and production days must be positive')
+
+    def weight_kg(self, metres):
+        return (self.base_kg + self.per_metre_kg * Decimal(str(metres))).quantize(Decimal('0.001'))
+
+    def quote(self, service, postal_code, metres=None, declared_cents=0):
+        if service == 'pickup':
+            return {'provider': self.name, 'service': 'pickup', 'total_cents': 0, 'postal_code': ''}
+        if service != SERVICE or len(postal_code) != 8 or not postal_code.isascii() or not postal_code.isdigit():
+            raise ValueError('Select pickup or Jadlog delivery with an eight-digit CEP')
+        if metres is None or Decimal(str(metres)) <= 0:
+            raise ValueError('The order length is required to quote freight')
+        weight = self.weight_kg(metres)
+        try:
+            result = self.quotes.quote(postal_code, weight, int(declared_cents))
+        except (JadlogError, httpx.HTTPError) as error:
+            raise ValueError(f'Não foi possível cotar o frete na Jadlog agora: {error}') from None
+        days = result['days']
+        return {'provider': self.name, 'service': SERVICE, 'postal_code': postal_code,
+                'total_cents': result['total_cents'], 'weight_kg': str(weight),
+                'days': None if days is None else int(days) + self.production_days,
+                'description': 'Jadlog .PACKAGE'}