fix(deals): preserve template deal details on readback

src/ad_seller/interfaces/api/contract_mappers.py

@@ -350,7 +350,24 @@ def internal_deal_status_to_wire(status: Any) -> DealStatus:
 
 def internal_deal_to_shared_deal(data: dict[str, Any]) -> Deal:
     """Build the shared :class:`Deal` primitive from the internal deal dict."""
-    product = data.get("product", {})
+    # Template bookings store flat fields. Preserve nested quote-booked
+    # sections when present, including deliberately empty sections.
+    product = data.get("product")
+    if product is None:
+        product = {"product_id": data.get("product_id", "")}
+    pricing = data.get("pricing")
+    if pricing is None:
+        pricing = {
+            "final_cpm": data.get("actual_price_cpm"),
+            "currency": data.get("currency", "USD"),
+        }
+    terms = data.get("terms")
+    if terms is None:
+        terms = {
+            "impressions": data.get("impressions"),
+            "flight_start": data.get("flight_start"),
+            "flight_end": data.get("flight_end"),
+        }
     return Deal(
         deal_id=data["deal_id"],
         deal_type=DealType(data["deal_type"]),
@@ -361,8 +378,8 @@ def internal_deal_to_shared_deal(data: dict[str, Any]) -> Deal:
             name=product.get("name", ""),
             inventory_type=product.get("inventory_type"),
         ),
-        pricing=_quote_pricing_to_shared(data.get("pricing", {})),
-        terms=_quote_terms_to_shared(data.get("terms", {})),
+        pricing=_quote_pricing_to_shared(pricing),
+        terms=_quote_terms_to_shared(terms),
         buyer_tier=AccessTier(data.get("buyer_tier", "public")),
         seller_id=data.get("seller_id"),
         expires_at=_parse_dt(data.get("expires_at")),

tests/unit/test_deal_status_wire_mapping.py

@@ -194,6 +194,42 @@ def test_confirmed_deal_dict_maps_to_shared_deal(self):
 
 
 class TestGetDealCreatedOutsideQuotePath:
+    async def test_template_post_and_get_preserve_the_booked_terms(self, client, mock_storage):
+        app.dependency_overrides[_get_optional_api_key_record] = lambda: SimpleNamespace(
+            identity=BuyerIdentity()
+        )
+        with (
+            patch("ad_seller.storage.factory.get_storage", return_value=mock_storage),
+            patch(
+                "ad_seller.interfaces.api.deps.get_product_catalog",
+                new=AsyncMock(return_value=_mock_catalog()),
+            ),
+        ):
+            created = await client.post(
+                "/api/v1/deals/from-template",
+                json={
+                    "deal_type": "PD",
+                    "product_id": "ctv-premium-sports",
+                    "impressions": 1_000_000,
+                    "flight_start": "2026-10-06",
+                    "flight_end": "2026-11-05",
+                },
+            )
+            assert created.status_code == 201, created.text
+            booked = created.json()
+            response = await client.get(f"/api/v1/deals/{booked['deal_id']}")
+
+        assert response.status_code == 200, response.text
+        deal = response.json()["deal"]
+        assert deal["product"]["product_id"] == booked["product_id"]
+        assert deal["pricing"]["final_cpm"] == {
+            "amount_micros": round(booked["actual_price_cpm"] * 1_000_000),
+            "currency": "USD",
+        }
+        assert deal["terms"]["impressions"] == booked["impressions"]
+        assert deal["terms"]["flight_start"] == booked["flight_start"]
+        assert deal["terms"]["flight_end"] == booked["flight_end"]
+
     async def test_from_template_deal_is_readable_as_booked(self, client, mock_storage):
         """Create via the from-template service path (what the REST route
         and the MCP tool both call), then GET through the wire mapper."""

tests/unit/test_template_deal_readback.py

@@ -0,0 +1,83 @@
+"""Template deal fields survive conversion into the shared wire contract."""
+
+from copy import deepcopy
+from datetime import date
+
+import pytest
+
+from ad_seller.interfaces.api import contract_mappers as cm
+
+
+def _flat_deal():
+    return {
+        "deal_id": "DEMO-TEMPLATE",
+        "deal_type": "PD",
+        "status": "confirmed",
+        "product_id": "ctv-sports",
+        "actual_price_cpm": 28.26,
+        "currency": "EUR",
+        "impressions": 1_000_000,
+        "flight_start": "2026-10-06",
+        "flight_end": "2026-11-05",
+        "created_at": "2026-10-05T12:00:00Z",
+    }
+
+
+@pytest.mark.parametrize("null_sections", [False, True])
+def test_flat_template_fields_are_mapped_without_changing_storage(null_sections):
+    stored = _flat_deal()
+    if null_sections:
+        stored.update(product=None, pricing=None, terms=None)
+    original = deepcopy(stored)
+
+    deal = cm.internal_deal_to_shared_deal(stored)
+
+    assert deal.product.product_id == "ctv-sports"
+    assert deal.product.name == ""
+    assert deal.pricing.final_cpm.amount_micros == 28_260_000
+    assert deal.pricing.final_cpm.currency == "EUR"
+    assert deal.pricing.base_cpm is None
+    assert deal.terms.impressions == 1_000_000
+    assert deal.terms.flight_start == date(2026, 10, 6)
+    assert deal.terms.flight_end == date(2026, 11, 5)
+    assert stored == original
+
+
+def test_nested_sections_remain_authoritative_over_conflicting_flat_fields():
+    stored = _flat_deal()
+    stored.update(
+        product={"product_id": "nested-product", "name": "Booked product"},
+        pricing={"base_cpm": 40, "final_cpm": 32, "currency": "USD"},
+        terms={"impressions": 2_000_000, "flight_start": "2026-12-01", "guaranteed": True},
+    )
+    original = deepcopy(stored)
+
+    deal = cm.internal_deal_to_shared_deal(stored)
+
+    assert deal.product.product_id == "nested-product"
+    assert deal.product.name == "Booked product"
+    assert deal.pricing.base_cpm.amount_micros == 40_000_000
+    assert deal.pricing.final_cpm.amount_micros == 32_000_000
+    assert deal.pricing.final_cpm.currency == "USD"
+    assert deal.terms.impressions == 2_000_000
+    assert deal.terms.flight_start == date(2026, 12, 1)
+    assert deal.terms.flight_end is None
+    assert deal.terms.guaranteed is True
+    assert stored == original
+
+
+def test_empty_nested_sections_do_not_pick_up_flat_values():
+    deal = cm.internal_deal_to_shared_deal(
+        {**_flat_deal(), "product": {}, "pricing": {}, "terms": {}}
+    )
+    assert deal.product.product_id == ""
+    assert deal.pricing.final_cpm is None
+    assert deal.terms.impressions is None
+
+
+def test_zero_price_and_impressions_are_preserved():
+    deal = cm.internal_deal_to_shared_deal(
+        {**_flat_deal(), "actual_price_cpm": 0, "impressions": 0}
+    )
+    assert deal.pricing.final_cpm.amount_micros == 0
+    assert deal.terms.impressions == 0