fix: align CM93 lookup flow with OpenCPN

src/cm95pbf/__init__.py

@@ -1,2 +1,2 @@
-__version__ = "0.4.13-s52-ordered-rule-ir"
-BUILDER_CONTRACT_VERSION = "cm95pbf-builder/0.4.13-s52-ordered-rule-ir"
+__version__ = "0.4.14-s52-opencpn-lookup-flow"
+BUILDER_CONTRACT_VERSION = "cm95pbf-builder/0.4.14-s52-opencpn-lookup-flow"

src/cm95pbf/s52.py

@@ -1,5 +1,7 @@
 from __future__ import annotations
 
+import re
+import struct
 from typing import Any, Iterable
 
 from .presentation import (
@@ -102,16 +104,36 @@ def normalize_cm93_object_class_for_s52(object_class: str) -> str:
 def normalize_cm93_object_for_s52(
     object_class: str, geometry_type: str, attrs: dict[str, Any]
 ) -> tuple[str, dict[str, Any]]:
-    """Normalize CM93 class/attributes into the S-57/S-52 presentation view."""
+    """Normalize CM93 class/attributes into the fixed OpenCPN S-52 view."""
     source_class = str(object_class or "")
+    lookup_class = normalize_cm93_object_class_for_s52(source_class)
     out = normalize_cm93_attributes_for_s52(attrs)
+
+    if source_class == "$AREAS" and str(out.get("$SCODE") or "") == "II25":
+        out["$SCODE"] = "BACKGROUND"
+
     if str(geometry_type).upper() == "POINT":
         catlmk = CM93_LANDMARK_CLASS_TO_CATLMK.get(source_class)
         if catlmk is not None:
             out.setdefault("CATLMK", catlmk)
+
+        aton = (
+            lookup_class.startswith("LIT")
+            or lookup_class.startswith("LIGHTS")
+            or lookup_class.startswith("BCN")
+            or lookup_class.startswith("_slgto")
+            or lookup_class.startswith("_boygn")
+            or lookup_class.startswith("_bcngn")
+            or lookup_class.startswith("_extgn")
+            or lookup_class.startswith("TOWERS")
+            or lookup_class.startswith("BOY")
+        )
+        if aton and "OBJNAM" not in out and "INFORM" in out:
+            out["OBJNAM"] = out.pop("INFORM")
+
     for key, value in CM93_CLASS_SYNTHETIC_ATTRIBUTES.get(source_class, {}).items():
         out.setdefault(key, value)
-    return normalize_cm93_object_class_for_s52(source_class), out
+    return lookup_class, out
 
 
 CM93_COLMAR_TO_S57_COLOUR: dict[int, str] = {
@@ -175,9 +197,15 @@ def _s57_list_string(value: Any) -> str | None:
 
 
 def normalize_cm93_attributes_for_s52(attrs: dict[str, Any]) -> dict[str, Any]:
-    """Return S-57/S-52-compatible attributes without mutating CM93 raw data."""
+    """Return the fixed OpenCPN CM93-to-S57 typed attribute view."""
     out = dict(attrs)
 
+    for key, value in list(out.items()):
+        if len(str(key)) == 6 and isinstance(value, (list, tuple)):
+            normalized = _s57_list_string(value)
+            if normalized is not None:
+                out[key] = normalized
+
     if "COLOUR" in out:
         value = _s57_list_string(out.get("COLOUR"))
         if value is not None:
@@ -191,6 +219,11 @@ def normalize_cm93_attributes_for_s52(attrs: dict[str, Any]) -> dict[str, Any]:
         if translated is not None:
             out["COLOUR"] = translated
 
+    for key in ("QUASOU", "CATLIT"):
+        value = out.get(key)
+        if isinstance(value, int):
+            out[key] = str(int(value))
+
     return out
 
 
@@ -201,28 +234,41 @@ def split_lookup_condition(condition: str) -> tuple[str, str]:
     return text[:6].upper(), text[6:]
 
 
+def _c_atoi(value: str) -> int:
+    """Minimal C atoi semantics used by fixed OpenCPN FindBestLUP."""
+    match = re.match(r"^[\s]*([+-]?\d+)", str(value))
+    return int(match.group(1)) if match else 0
+
+
+def _c_atof_float32(value: str) -> float:
+    """OpenCPN assigns atof() to float before exact REAL comparison."""
+    try:
+        parsed = float(str(value).strip() or "0")
+    except ValueError:
+        parsed = 0.0
+    return struct.unpack("f", struct.pack("f", parsed))[0]
+
+
 def lookup_condition_matches(condition: str, attrs: dict[str, Any]) -> bool:
+    """Match one condition as fixed OpenCPN FindBestLUP does."""
     acronym, expected = split_lookup_condition(condition)
     actual_present = acronym in attrs and attrs.get(acronym) is not None
 
     if expected.startswith(" "):
         return actual_present
     if expected.startswith("?"):
-        return not actual_present
+        # Preserve the fixed-source quirk: this path never increments countATT.
+        return False
     if not actual_present:
         return False
 
     actual = attrs.get(acronym)
-    if isinstance(actual, (list, tuple)):
-        actual = _s57_list_string(actual)
-    elif isinstance(actual, bool):
+    if isinstance(actual, bool):
         actual = int(actual)
-
-    if isinstance(actual, (int, float)):
-        try:
-            return abs(float(actual) - float(expected)) < 1e-6
-        except (TypeError, ValueError):
-            return False
+    if isinstance(actual, int):
+        return actual == _c_atoi(expected)
+    if isinstance(actual, float):
+        return actual == _c_atof_float32(expected)
     return str(actual) == expected
 
 
@@ -234,7 +280,7 @@ def _lookup_sequence(row: dict[str, Any]) -> int:
 
 
 def sort_lookup_candidates(rows: Iterable[dict[str, Any]]) -> list[dict[str, Any]]:
-    """Match OpenCPN CompareLUPObjects: most conditions first, then sequence."""
+    """Match fixed OpenCPN CompareLUPObjects."""
     return sorted(
         rows,
         key=lambda row: (
@@ -244,6 +290,10 @@ def sort_lookup_candidates(rows: Iterable[dict[str, Any]]) -> list[dict[str, Any
     )
 
 
+def _has_lookup_visible_attributes(attrs: dict[str, Any]) -> bool:
+    return any(len(str(key)) == 6 and value is not None for key, value in attrs.items())
+
+
 def find_best_lookup(
     rows: Iterable[dict[str, Any]],
     attrs: dict[str, Any],
@@ -251,6 +301,7 @@ def find_best_lookup(
     table_name: str | None = None,
     geometry_type: str | None = None,
 ) -> dict[str, Any] | None:
+    """Reproduce non-strict fixed OpenCPN FindBestLUP selection."""
     normalized = normalize_cm93_attributes_for_s52(attrs)
     candidates = []
     for row in rows:
@@ -260,16 +311,29 @@ def find_best_lookup(
             continue
         candidates.append(row)
 
-    fallback: dict[str, Any] | None = None
-    for row in sort_lookup_candidates(candidates):
+    ordered = sort_lookup_candidates(candidates)
+    if not ordered:
+        return None
+
+    first = ordered[0]
+    if not _has_lookup_visible_attributes(normalized):
+        return first
+
+    for row in ordered:
         conditions = row.get("attribute_conditions_raw") or []
         if not conditions:
-            if fallback is None:
-                fallback = row
             continue
-        if all(lookup_condition_matches(c, normalized) for c in conditions):
+        count_att = sum(
+            1 for condition in conditions
+            if lookup_condition_matches(condition, normalized)
+        )
+        if count_att == len(conditions):
             return row
-    return fallback
+
+    for row in ordered:
+        if not (row.get("attribute_conditions_raw") or []):
+            return row
+    return first
 
 
 def primary_symbol_code(row: dict[str, Any] | None) -> str | None: