Initial GeoIntel V1 foundation

backend/app/utils/geometry.py

@@ -0,0 +1,58 @@
+from __future__ import annotations
+
+from typing import Any
+
+from pyproj import Transformer
+from shapely.geometry import GeometryCollection, MultiPolygon, Polygon, box, shape
+from shapely.ops import transform
+from shapely.validation import make_valid
+
+
+def normalize_to_multipolygon(raw_geometry: dict[str, Any]) -> MultiPolygon:
+    geom = shape(raw_geometry)
+    if geom.is_empty:
+        raise ValueError("Geometry is empty")
+
+    if not geom.is_valid:
+        geom = make_valid(geom)
+
+    if not geom.is_valid:
+        raise ValueError("Geometry is invalid and could not be repaired")
+
+    if geom.geom_type == "Polygon":
+        return MultiPolygon([geom])
+    if geom.geom_type == "MultiPolygon":
+        return MultiPolygon(geom.geoms)
+    if isinstance(geom, GeometryCollection):
+        polygons = [g for g in geom.geoms if isinstance(g, Polygon)]
+        multipolygons = [g for g in geom.geoms if g.geom_type == "MultiPolygon"]
+        if not polygons and not multipolygons:
+            raise ValueError("Only polygon geometries are supported for AOI")
+        normalized = []
+        normalized.extend(polygons)
+        for mp in multipolygons:
+            normalized.extend(mp.geoms)
+        return MultiPolygon(normalized)
+
+    raise ValueError("Only Polygon or MultiPolygon geometries are accepted")
+
+
+def area_bounds_multipolygon(geom: MultiPolygon):
+    return {
+        "min_x": float(geom.bounds[0]),
+        "min_y": float(geom.bounds[1]),
+        "max_x": float(geom.bounds[2]),
+        "max_y": float(geom.bounds[3]),
+    }
+
+
+def area_m2(geom: MultiPolygon) -> float:
+    projected = transform(
+        Transformer.from_crs("EPSG:4326", "EPSG:31370", always_xy=True).transform,
+        geom,
+    )
+    return float(projected.area)
+
+
+def geometry_bbox_polygon(geom: MultiPolygon):
+    return box(*geom.bounds)