From 4942824526ca3e061515449a59234115f94a3b23 Mon Sep 17 00:00:00 2001
From: Jan Petykiewicz <jan@mpxd.net>
Date: Tue, 21 Apr 2026 22:55:52 -0700
Subject: [PATCH] Add engine type aggregate parser views

---
 .../rrt-runtime/src/inspect/engine_types.rs   | 28 +++++++++++++++++--
 1 file changed, 25 insertions(+), 3 deletions(-)

diff --git a/crates/rrt-runtime/src/inspect/engine_types.rs b/crates/rrt-runtime/src/inspect/engine_types.rs
index 2815e02..e5fb8f8 100644
--- a/crates/rrt-runtime/src/inspect/engine_types.rs
+++ b/crates/rrt-runtime/src/inspect/engine_types.rs
@@ -150,6 +150,8 @@ pub struct EngineTypesInspectionReport {
     pub lco_body_type_label_counts: BTreeMap<String, usize>,
     pub cgo_scalar_value_counts: BTreeMap<String, usize>,
     pub cgo_scalar_values_by_content_stem: BTreeMap<String, Vec<String>>,
+    pub cct_identifier_counts: BTreeMap<String, usize>,
+    pub cct_value_counts: BTreeMap<String, usize>,
     pub locomotive_display_census: EngineTypeLocomotiveDisplayCensusReport,
     pub families: Vec<EngineTypeFamilyEntry>,
 }
@@ -371,6 +373,16 @@ pub fn inspect_engine_types_dir(
     );
     let cgo_scalar_values_by_content_stem =
         build_cgo_scalar_values_by_content_stem(cgo_reports.values());
+    let cct_identifier_counts = count_named_values(
+        family_entries
+            .iter()
+            .filter_map(|family| family.cct_identifier.as_deref()),
+    );
+    let cct_value_counts = count_owned_values(
+        family_entries
+            .iter()
+            .filter_map(|family| family.cct_value.map(|value| value.to_string())),
+    );
     let locomotive_display_census =
         build_locomotive_display_census(path, &family_entries, &car_reports)?;
 
@@ -420,6 +432,8 @@ pub fn inspect_engine_types_dir(
         lco_body_type_label_counts,
         cgo_scalar_value_counts,
         cgo_scalar_values_by_content_stem,
+        cct_identifier_counts,
+        cct_value_counts,
         locomotive_display_census,
         families: family_entries,
     })
@@ -586,14 +600,15 @@ fn read_lco_companion_stem(bytes: &[u8]) -> Option<String> {
     slot_is_padded(bytes, LCO_INTERNAL_STEM_OFFSET, 0x08)
         .then(|| read_ascii_slot(bytes, LCO_COMPANION_STEM_OFFSET, LCO_COMPANION_STEM_LEN))
         .flatten()
+        .filter(|value| value.len() >= 4)
 }
 
 fn read_lco_body_type_label(bytes: &[u8]) -> Option<String> {
-    let companion_slot_is_padded =
-        slot_is_padded(bytes, LCO_COMPANION_STEM_OFFSET, LCO_COMPANION_STEM_LEN);
-    companion_slot_is_padded
+    let _companion_stem = read_lco_companion_stem(bytes)?;
+    slot_is_padded(bytes, LCO_COMPANION_STEM_OFFSET, LCO_COMPANION_STEM_LEN)
         .then(|| read_ascii_slot(bytes, LCO_BODY_TYPE_LABEL_OFFSET, LCO_BODY_TYPE_LABEL_LEN))
         .flatten()
+        .filter(|value| value.len() >= 4)
 }
 
 fn parse_cct_row(line: &str) -> (Option<String>, Option<i64>) {
@@ -853,6 +868,13 @@ mod tests {
         );
     }
 
+    #[test]
+    fn counts_owned_value_strings() {
+        let counts = count_owned_values(["13".to_string(), "13".to_string(), "4".to_string()].into_iter());
+        assert_eq!(counts.get("13"), Some(&2));
+        assert_eq!(counts.get("4"), Some(&1));
+    }
+
     #[test]
     fn builds_locomotive_display_census() {
         let mut car_reports = BTreeMap::new();