Support more region utils, such as convex hull

api/s32_region_util.py

@@ -1,3 +1,4 @@
+from .database import read, read_all, write
 
 def from_postgis_polygon(polygon: str) -> list[tuple[float, float]]:
     boundary = polygon.lower().removeprefix('polygon((').removesuffix('))').split(',')
@@ -13,3 +14,36 @@ def to_postgis_polygon(boundary: list[tuple[float, float]]) -> str:
     for pt in boundary:
         polygon += f'{pt[0]} {pt[1]},'
     return f'polygon(({polygon[:-1]}))'
+
+
+def get_nodes_in_boundary(name: str, boundary: list[tuple[float, float]]) -> list[str]:
+    api = 'get_nodes_in_boundary'
+    write(name, f"delete from temp_region where id = '{api}'")
+    write(name, f"insert into temp_region (id, boundary) values ('{api}', '{to_postgis_polygon(boundary)}')")
+
+    nodes: list[str] = []
+    for row in read_all(name, f"select c.node from coordinates as c, temp_region as r where ST_Intersects(c.coord, r.boundary) and r.id = '{api}'"):
+        nodes.append(row['node'])
+
+    write(name, f"delete from temp_region where id = '{api}'")
+
+    return nodes
+
+
+def get_nodes_in_region(name: str, id: str) -> list[str]:
+    nodes: list[str] = []
+    for row in read_all(name, f"select c.node from coordinates as c, region as r where ST_Intersects(c.coord, r.boundary) and r.id = '{id}'"):
+        nodes.append(row['node'])
+    return nodes
+
+
+def calculate_convex_hull(name: str, nodes: list[str]) -> list[tuple[float, float]]:
+    write(name, f'delete from temp_node')
+    for node in nodes:
+        write(name, f"insert into temp_node values ('{node}')")
+
+    # TODO: check none
+    polygon = read(name, f'select st_astext(st_convexhull(st_collect(array(select coord from coordinates where node in (select * from temp_node))))) as boundary' )['boundary']
+    write(name, f'delete from temp_node')
+
+    return from_postgis_polygon(polygon)