fix error in gitignore

2026-09-24 12:32:59 +03:30
commit 86c117ee2a
165 changed files with 5963 additions and 0 deletions
@@ -0,0 +1,81 @@
+"""Order lifecycle service — ties reservations, weighing, dynamic step
+selection, pricing and confirmation together. All financial values are
+computed by the backend and stored as immutable snapshots."""
+from decimal import Decimal
+
+from django.db import transaction
+from django.utils import timezone
+
+from apps.core.errors import ApiError
+from apps.orders.models import ProcessingOrder
+from apps.pricing.engine import PricingEngine
+from apps.workflows.models import Workflow
+
+
+class OrderService:
+    def _active_workflow(self) -> Workflow:
+        workflow = Workflow.objects.filter(status="active", active_version__isnull=False).first()
+        if workflow is None:
+            raise ApiError("NO_ACTIVE_WORKFLOW", "No active workflow is configured.")
+        return workflow
+
+    @transaction.atomic
+    def create_from_reservation(self, reservation, workflow=None) -> ProcessingOrder:
+        if ProcessingOrder.objects.filter(reservation=reservation).exists():
+            raise ApiError("ORDER_EXISTS", "An order already exists for this reservation.")
+        if workflow is None:
+            workflow = self._active_workflow()
+        return ProcessingOrder.objects.create(
+            customer=reservation.customer,
+            reservation=reservation,
+            workflow_version=workflow.active_version,
+        )
+
+    @transaction.atomic
+    def record_weighing(self, order, gross, tare) -> ProcessingOrder:
+        order = ProcessingOrder.objects.select_for_update().get(pk=order.pk)
+        if order.net_weight_kg is not None:
+            raise ApiError("WEIGHING_IMMUTABLE", "Net weight is already recorded and immutable.")
+        gross = Decimal(str(gross))
+        tare = Decimal(str(tare))
+        if gross < tare:
+            raise ApiError("INVALID_WEIGHT", "Gross weight cannot be less than tare weight.")
+        order.gross_weight_kg = gross
+        order.tare_weight_kg = tare
+        order.net_weight_kg = gross - tare
+        order.save(update_fields=["gross_weight_kg", "tare_weight_kg", "net_weight_kg"])
+        return order
+
+    @transaction.atomic
+    def select_steps(self, order, step_keys) -> ProcessingOrder:
+        order = ProcessingOrder.objects.select_for_update().get(pk=order.pk)
+        if order.net_weight_kg is None:
+            raise ApiError("WEIGHING_REQUIRED", "Record weighing before selecting processing.")
+        version = order.workflow_version
+        steps = list(version.steps.filter(key__in=step_keys, enabled=True))
+        keys = {s.key for s in steps}
+        for required in version.steps.filter(required=True):
+            if required.key not in keys:
+                raise ApiError(
+                    "REQUIRED_STEP_MISSING",
+                    f"Required step '{required.key}' must be selected.",
+                    {"step": required.key},
+                )
+        order.selected_step_keys = sorted(keys)
+        order.price_snapshot = PricingEngine().calculate(order.net_weight_kg, steps, order.currency)
+        order.status = ProcessingOrder.Status.AWAITING_CONFIRMATION
+        order.save(update_fields=["selected_step_keys", "price_snapshot", "status"])
+        return order
+
+    @transaction.atomic
+    def confirm(self, order, terms_accepted=True) -> ProcessingOrder:
+        order = ProcessingOrder.objects.select_for_update().get(pk=order.pk)
+        if order.status != ProcessingOrder.Status.AWAITING_CONFIRMATION:
+            raise ApiError("ORDER_NOT_CONFIRMABLE", "Order is not awaiting confirmation.")
+        if not terms_accepted:
+            raise ApiError("TERMS_REQUIRED", "Terms must be accepted.")
+        order.status = ProcessingOrder.Status.CONFIRMED
+        order.confirmed_at = timezone.now()
+        order.terms_accepted = True
+        order.save(update_fields=["status", "confirmed_at", "terms_accepted"])
+        return order