Add Gamma SBAS production workflow

backend/app/services/water_extraction_service.py

@@ -0,0 +1,33 @@
+"""Water extraction processors for the flood-analysis pipeline."""
+from __future__ import annotations
+
+from typing import Any
+
+
+def run_otsu_water_extraction(
+    *,
+    input_path: str,
+    output_dir: str,
+    job_id: str | None = None,
+) -> dict[str, Any]:
+    """Run the fast Otsu water-extraction processor.
+
+    This wraps the legacy implementation while exposing the terminology used by
+    the flood pipeline: extraction, processor and threshold_value.
+    """
+    from .water_detect_service import run_water_detection
+
+    result = run_water_detection(
+        geo_tiff_path=input_path,
+        output_dir=output_dir,
+        job_id=job_id,
+    )
+    result["processor"] = "otsu"
+    if "threshold_value" not in result and "otsu_threshold_db" in result:
+        result["threshold_value"] = result.get("otsu_threshold_db")
+    return result
+
+
+def run_envi_water_extraction(*args: Any, **kwargs: Any) -> dict[str, Any]:
+    """Placeholder for the future ENVI/SARscape precise extractor."""
+    raise NotImplementedError("ENVI/SARscape water extraction is not wired yet")