Add atmospheric-correction registry scaffold

src/earthrs/processing/atmospheric.py

@@ -1,21 +1,33 @@
-"""Atmospheric-correction processing placeholder."""
+"""Atmospheric-correction processing routines."""
 
 from __future__ import annotations
 
 from typing import Any
 
+from earthrs.processing.core import _ATMOSPHERIC_REGISTRY, register_atmospheric_method
 from earthrs.scene import Scene
 
 
 def atmospheric_correction(scene: Scene, *, method: str = "default", **kwargs: Any) -> Scene:
     """Apply atmospheric correction to reflectance inputs.
 
-    The function is registry-ready but atmospheric correction is not yet implemented.
+    Method names are resolved from the atmospheric-correction registry. Atmospheric
+    correction is not yet implemented, so the registered ``"default"`` method raises
+    ``NotImplementedError``.
     """
 
+    processor = _ATMOSPHERIC_REGISTRY.get(method.lower())
+    if processor is None:
+        raise ValueError(f"Unknown atmospheric-correction method '{method}'.")
+    return processor(scene, **kwargs)
+
+
+def _default_atmospheric_correction(scene: Scene, **kwargs: Any) -> Scene:
     _ = scene
-    _ = method
     _ = kwargs
     raise NotImplementedError(
         "Atmospheric correction is not yet implemented. Check for a new version of earthrs."
     )
+
+
+register_atmospheric_method("default", _default_atmospheric_correction)

src/earthrs/processing/core.py

@@ -11,10 +11,12 @@
 GlintProcessor = Any
 DepthProcessor = Any
 CloudProcessor = Any
+AtmosphericProcessor = Any
 
 _GLINT_REGISTRY: dict[str, GlintProcessor] = {}
 _DEPTH_REGISTRY: dict[str, DepthProcessor] = {}
 _CLOUD_REGISTRY: dict[str, CloudProcessor] = {}
+_ATMOSPHERIC_REGISTRY: dict[str, AtmosphericProcessor] = {}
 
 
 def register_glint_method(name: str, func: GlintProcessor) -> None:
@@ -29,6 +31,10 @@ def register_cloud_method(name: str, func: CloudProcessor) -> None:
     _CLOUD_REGISTRY[name.lower()] = func
 
 
+def register_atmospheric_method(name: str, func: AtmosphericProcessor) -> None:
+    _ATMOSPHERIC_REGISTRY[name.lower()] = func
+
+
 _RESAMPLING_METHODS = frozenset({"nearest", "bilinear"})
 
 Transform = tuple[float, float, float, float, float, float]

tests/test_processing.py

@@ -41,6 +41,36 @@ def test_atmospheric_correction_is_deferred() -> None:
         atmospheric_correction(scene)
 
 
+def test_atmospheric_correction_default_method_is_deferred() -> None:
+    scene = Scene(data={"blue": [0.1]}, band_names=["blue"])
+
+    with pytest.raises(NotImplementedError):
+        atmospheric_correction(scene, method="default")
+
+
+def test_atmospheric_correction_rejects_unknown_method() -> None:
+    scene = Scene(data={"blue": [0.1]}, band_names=["blue"])
+
+    with pytest.raises(ValueError):
+        atmospheric_correction(scene, method="not_a_method")
+
+
+def test_register_atmospheric_method_round_trips_through_registry() -> None:
+    from earthrs.processing.core import _ATMOSPHERIC_REGISTRY, register_atmospheric_method
+
+    def _dummy_processor(scene: Scene, **kwargs: object) -> Scene:
+        return scene
+
+    register_atmospheric_method("Dummy", _dummy_processor)
+    try:
+        assert _ATMOSPHERIC_REGISTRY["dummy"] is _dummy_processor
+
+        scene = Scene(data={"blue": [0.1]}, band_names=["blue"])
+        assert atmospheric_correction(scene, method="DUMMY") is scene
+    finally:
+        del _ATMOSPHERIC_REGISTRY["dummy"]
+
+
 def test_hedley_glint_removal_subtracts_scaled_nir_and_clamps_at_zero() -> None:
     scene = Scene(data={"nir": [10, 20], "red": [5, 8]}, band_names=["nir", "red"])