feat(backend): add store iterators (claims, remits, providers, activity)

backend/tests/test_store.py

@@ -203,3 +203,87 @@ def test_to_activity_event_uses_iso_timestamp():
     assert out["id"] == "a1"
     assert out["kind"] == "claim_submitted"
     assert out["amount"] == 100.0
+
+
+# ---------------------------------------------------------------------------
+# Task 3: Iterators
+# ---------------------------------------------------------------------------
+
+
+def test_iter_claims_filters_by_status():
+    s = InMemoryStore()
+    result = _make_result()
+    a = _make_claim("A")
+    b = _make_claim("B")
+    b.validation = ValidationReport(
+        passed=True, errors=[],
+        warnings=[ValidationIssue(rule="W1", severity="warning", message="x")],
+    )
+    result.claims = [a, b]
+    s.add(BatchRecord(
+        id="1", kind="837p", input_filename="a.txt",
+        parsed_at="2026-06-19T12:00:00Z", result=result,
+    ))
+    out = list(s.iter_claims(status="submitted"))
+    assert all(c["status"] == "submitted" for c in out)
+    assert any(c["id"] == "A" for c in out)
+    out_pending = list(s.iter_claims(status="pending"))
+    assert all(c["status"] == "pending" for c in out_pending)
+    assert any(c["id"] == "B" for c in out_pending)
+
+
+def test_iter_claims_filters_by_batch_id():
+    s = InMemoryStore()
+    s.add(BatchRecord(
+        id="b1", kind="837p", input_filename="a.txt",
+        parsed_at="2026-06-19T12:00:00Z", result=_make_result(),
+    ))
+    out = list(s.iter_claims(batch_id="b1"))
+    assert all(c["batchId"] == "b1" for c in out)
+
+
+def test_iter_claims_sorts_by_billed_amount_desc():
+    s = InMemoryStore()
+    result = _make_result()
+    result.claims = [
+        _make_claim("cheap"),
+        _make_claim("expensive"),
+    ]
+    result.claims[0].claim.total_charge = Decimal("50.00")
+    result.claims[1].claim.total_charge = Decimal("500.00")
+    s.add(BatchRecord(
+        id="b1", kind="837p", input_filename="a.txt",
+        parsed_at="2026-06-19T12:00:00Z", result=result,
+    ))
+    out = list(s.iter_claims(sort="billedAmount", order="desc"))
+    assert out[0]["id"] == "expensive"
+    assert out[1]["id"] == "cheap"
+
+
+def test_distinct_providers_aggregates_claims():
+    s = InMemoryStore()
+    result = _make_result()
+    result.claims = [_make_claim("A"), _make_claim("B")]
+    s.add(BatchRecord(
+        id="b1", kind="837p", input_filename="a.txt",
+        parsed_at="2026-06-19T12:00:00Z", result=result,
+    ))
+    out = s.distinct_providers()
+    assert len(out) == 1
+    assert out[0]["npi"] == "1234567890"
+    assert out[0]["claimCount"] == 2
+
+
+def test_recent_activity_returns_newest_first():
+    s = InMemoryStore()
+    s.add(BatchRecord(
+        id="b1", kind="837p", input_filename="a.txt",
+        parsed_at="2026-06-19T11:00:00Z", result=_make_result(),
+    ))
+    s.add(BatchRecord(
+        id="b2", kind="837p", input_filename="b.txt",
+        parsed_at="2026-06-19T12:00:00Z", result=_make_result(),
+    ))
+    out = s.recent_activity(limit=10)
+    assert out[0]["timestamp"] == "2026-06-19T12:00:00Z"
+    assert out[1]["timestamp"] == "2026-06-19T11:00:00Z"