fix: align WALOUS with official class codes

backend/app/services/walous_land_cover_service.py

@@ -41,13 +41,15 @@ class WalousProduct:
     download_url: str
     source_sha256_filename: str
     accuracy_label: str
+    observation_start: datetime
+    observation_end: datetime
 
 
 class WalousLandCoverService:
     PROVIDER = "spw_walous_land_cover"
     SOURCE_CRS = "EPSG:3812"
     SOURCE_RESOLUTION_M = 1.0
-    SOURCE_VALUE_UNIT = "class_1_11"
+    SOURCE_VALUE_UNIT = "walous_class_code"
     THEME = "land_cover_use"
     METRIC_KIND = "categorical_area"
     NODATA = 255
@@ -58,31 +60,33 @@ class WalousLandCoverService:
         "geconfigureerde analyseresolutie. Oppervlakten zijn celgebaseerde schattingen; de kaart is landbedekking, "
         "geen juridisch landgebruik, eigendom, boomtelling of actuele terreinwaarneming."
     )
+    # WALOUS has 11 semantic classes, but its official raster codes are not a
+    # continuous 1..11 range. Codes 80 and 90 distinguish low woody cover.
     CLASS_LABELS = {
-        1: "Jaarlijks wisselende kruidlaag",
-        2: "Jaarronde kruidlaag",
-        3: "Naaldbomen hoger dan 3 m",
-        4: "Loofbomen hoger dan 3 m",
-        5: "Naaldbomen tot 3 m",
-        6: "Loofbomen tot 3 m",
-        7: "Kale bodem",
-        8: "Oppervlaktewater",
-        9: "Kunstmatige bodembedekking",
-        10: "Spoorweg",
-        11: "Kunstmatige constructies boven maaiveld",
+        1: "Kunstmatige bodembedekking",
+        2: "Kunstmatige constructies boven maaiveld",
+        3: "Spoorweg",
+        4: "Kale bodem",
+        5: "Oppervlaktewater",
+        6: "Jaarlijks wisselende kruidlaag",
+        7: "Jaarronde kruidlaag",
+        8: "Naaldbomen hoger dan 3 m",
+        9: "Loofbomen hoger dan 3 m",
+        80: "Naaldbomen tot 3 m",
+        90: "Loofbomen tot 3 m",
     }
     CLASS_COLORS = {
-        1: (236, 202, 73),
-        2: (161, 201, 78),
-        3: (28, 89, 51),
-        4: (52, 132, 72),
-        5: (78, 125, 70),
-        6: (107, 164, 87),
-        7: (194, 165, 119),
-        8: (44, 129, 185),
-        9: (155, 155, 155),
-        10: (68, 68, 68),
-        11: (183, 72, 67),
+        1: (155, 155, 155),
+        2: (183, 72, 67),
+        3: (68, 68, 68),
+        4: (194, 165, 119),
+        5: (44, 129, 185),
+        6: (236, 202, 73),
+        7: (161, 201, 78),
+        8: (28, 89, 51),
+        9: (52, 132, 72),
+        80: (78, 125, 70),
+        90: (107, 164, 87),
     }
 
     @staticmethod
@@ -101,6 +105,8 @@ class WalousLandCoverService:
                 ),
                 source_sha256_filename="walous_land_cover_2020_3812.sha256",
                 accuracy_label="Officiele globale nauwkeurigheid 83,30%",
+                observation_start=datetime(2020, 4, 1, tzinfo=UTC),
+                observation_end=datetime(2020, 4, 24, 23, 59, 59, tzinfo=UTC),
             ),
             WalousProduct(
                 key="walous_land_cover_2023",
@@ -115,6 +121,8 @@ class WalousLandCoverService:
                 ),
                 source_sha256_filename="walous_land_cover_2023_3812.sha256",
                 accuracy_label="Officiele globale nauwkeurigheid 87,10%",
+                observation_start=datetime(2023, 5, 27, tzinfo=UTC),
+                observation_end=datetime(2023, 6, 25, 23, 59, 59, tzinfo=UTC),
             ),
         )
         return {product.key: product for product in products}
@@ -145,8 +153,8 @@ class WalousLandCoverService:
                     catalog_url=product.catalog_url,
                     attribution=WalousLandCoverService.ATTRIBUTION,
                     license_note=WalousLandCoverService.LICENSE_NOTE,
-                    legend_min_label="WALOUS klasse 1",
-                    legend_max_label="WALOUS klasse 11",
+                    legend_min_label="WALOUS klasse 1 (kunstmatige bodem)",
+                    legend_max_label="WALOUS klasse 90 (loofbomen tot 3 m)",
                     included_source_values=list(WalousLandCoverService.CLASS_LABELS),
                     limitation_message=f"{WalousLandCoverService.LIMITATION} {product.accuracy_label}.",
                     coverage_zones=["wallonia"],
@@ -250,7 +258,12 @@ class WalousLandCoverService:
                 classes = set(np.unique(valid).astype(int).tolist())
                 unexpected = sorted(classes - set(WalousLandCoverService.CLASS_LABELS))
                 if unexpected:
-                    raise AppError(code="WALOUS_SOURCE_INVALID_VALUES", message="WALOUS contains classes outside the governed 1-11 legend", details={"unexpected_classes": unexpected}, status_code=409)
+                    raise AppError(
+                        code="WALOUS_SOURCE_INVALID_VALUES",
+                        message="WALOUS contains classes outside the governed 11-class code set",
+                        details={"unexpected_classes": unexpected},
+                        status_code=409,
+                    )
                 profile = {
                     "driver": "GTiff",
                     "width": width,
@@ -345,7 +358,7 @@ class WalousLandCoverService:
         source_sha256_path = source_path.with_name(product.source_sha256_filename)
         source_sha256 = source_sha256_path.read_text(encoding="ascii").strip().split()[0] if source_sha256_path.is_file() else None
         acquired_at = datetime.now(UTC)
-        observed_at = datetime(product.observation_year, 12, 31, 23, 59, 59, tzinfo=UTC)
+        observed_at = product.observation_end
         spatial_series_hash = hashlib.sha256(json.dumps({"bbox": identity["bbox_epsg4326"], "area_id": identity["area_id"], "resolution": identity["analysis_resolution_m"]}, sort_keys=True).encode()).hexdigest()[:24]
         dataset = DatasetService.import_raster_bytes(
             db,
@@ -357,8 +370,8 @@ class WalousLandCoverService:
             source_name=WalousLandCoverService.PROVIDER,
             temporal_series_key=f"spw:walous:land-cover:{spatial_series_hash}",
             observed_at=observed_at,
-            valid_from=datetime(product.observation_year, 1, 1, tzinfo=UTC),
-            valid_to=observed_at,
+            valid_from=product.observation_start,
+            valid_to=product.observation_end,
             temporal_granularity="year",
             source_version=product.source_version,
             source_metadata={
@@ -374,6 +387,8 @@ class WalousLandCoverService:
                 "source_value_unit": WalousLandCoverService.SOURCE_VALUE_UNIT,
                 "class_labels": WalousLandCoverService.CLASS_LABELS,
                 "observation_year": product.observation_year,
+                "observation_start": product.observation_start.isoformat(),
+                "observation_end": product.observation_end.isoformat(),
                 "valid_pixel_count": validation["valid_pixel_count"],
                 "classes_present": validation["classes_present"],
                 "bbox_epsg4326": bbox_4326,
@@ -480,12 +495,12 @@ class WalousLandCoverService:
 
         metric_specs = [
             ("land_cover_observed_area_ha", "Gekarteerde landbedekking", set(WalousLandCoverService.CLASS_LABELS)),
-            ("forest_cover_area_ha", "Boom- en bosbedekking", {3, 4, 5, 6}),
-            ("surface_water_area_ha", "Oppervlaktewater", {8}),
-            ("artificial_cover_area_ha", "Kunstmatige bedekking en constructies", {9, 10, 11}),
-            ("annual_herbaceous_cover_area_ha", "Jaarlijks wisselende kruidlaag", {1}),
-            ("permanent_herbaceous_cover_area_ha", "Jaarronde kruidlaag", {2}),
-            ("bare_soil_area_ha", "Kale bodem", {7}),
+            ("forest_cover_area_ha", "Boom- en bosbedekking", {8, 9, 80, 90}),
+            ("surface_water_area_ha", "Oppervlaktewater", {5}),
+            ("artificial_cover_area_ha", "Kunstmatige bedekking en constructies", {1, 2, 3}),
+            ("annual_herbaceous_cover_area_ha", "Jaarlijks wisselende kruidlaag", {6}),
+            ("permanent_herbaceous_cover_area_ha", "Jaarronde kruidlaag", {7}),
+            ("bare_soil_area_ha", "Kale bodem", {4}),
         ]
         metrics = [
             ThematicRasterMetric(