Add sweep clustering

backend/python/app/services/implementations/sweep_algorithm_test.py

@@ -0,0 +1,171 @@
+#!/usr/bin/env python3
+"""
+Test script for Sweep clustering with real database locations.
+
+Run from backend/python (or from repo root with PYTHONPATH=backend/python):
+  python -m app.services.implementations.sweep_algorithm_test
+
+Or run this file directly (from any directory):
+  python backend/python/app/services/implementations/sweep_algorithm_test.py
+"""
+
+import os
+import sys
+
+sys.path.insert(0, "/app")
+
+import matplotlib.pyplot as plt
+import pandas as pd
+import seaborn as sns
+from sqlmodel import Session, create_engine, func, select
+
+from app.models.location import Location
+from app.models.route_stop import RouteStop  # noqa: F401
+from app.models.system_settings import SystemSettings
+from app.services.implementations.sweep_clustering import (
+    SweepClusteringAlgorithm,
+)
+
+# Use the same connection string as seed_database.py
+DATABASE_URL = "postgresql://postgres:postgres@f4k_db:5432/f4k"
+
+# Configure number of locations pulled from csv for testing
+LOCATIONS_COUNT = 18
+
+NUM_CLUSTERS = 10
+MAX_LOCATIONS_PER_CLUSTER = 5
+MAX_BOXES_PER_CLUSTER = 50
+
+
+async def main() -> None:
+    engine = create_engine(DATABASE_URL, echo=False)
+
+    with Session(engine) as session:
+        # Fetch locations that have coordinates
+        statement = (
+            select(Location)
+            .where(Location.latitude is not None, Location.longitude is not None)
+            .order_by(func.random())
+            .limit(LOCATIONS_COUNT)
+        )
+
+        locations = list(session.exec(statement).all())
+
+        print(f"Fetched {len(locations)} locations from database\n")
+
+        if len(locations) < 2:
+            print("Not enough locations with coordinates to cluster!")
+            return
+
+        warehouse_lat: float
+        warehouse_lon: float
+        system_settings = session.exec(select(SystemSettings).limit(1)).first()
+        warehouse_lat = system_settings.warehouse_latitude
+        warehouse_lon = system_settings.warehouse_longitude
+        print(
+            f"Using warehouse from system settings: ({warehouse_lat}, {warehouse_lon})\n"
+        )
+
+        total_boxes = sum(loc.num_boxes for loc in locations)
+
+        print("Locations to cluster:")
+        print("-" * 60)
+        for loc in locations:
+            name = loc.school_name or loc.contact_name
+            print(f"  {name}")
+            print(f"    Address: {loc.address}")
+            print(f"    Coords: ({loc.latitude}, {loc.longitude})")
+            print(f"    Boxes: {loc.num_boxes}")
+            print()
+
+        print("Total number of boxes: ", total_boxes)
+        print("Total locations: ", len(locations))
+
+        clustering_algo = SweepClusteringAlgorithm()
+
+        print("Running Sweep clustering:")
+        print(f"  - Number of clusters: {NUM_CLUSTERS}")
+        print(f"  - Max locations per cluster: {MAX_LOCATIONS_PER_CLUSTER}")
+        print(f"  - Max boxes per cluster: {MAX_BOXES_PER_CLUSTER}")
+        print("-" * 60)
+
+        try:
+            clusters = await clustering_algo.cluster_locations(
+                locations=locations,
+                num_clusters=NUM_CLUSTERS,
+                warehouse_lat=warehouse_lat,
+                warehouse_lon=warehouse_lon,
+                max_locations_per_cluster=MAX_LOCATIONS_PER_CLUSTER,
+                max_boxes_per_cluster=MAX_BOXES_PER_CLUSTER,
+                timeout_seconds=30.0,
+            )
+
+            print("\nClustering Results:")
+            print("=" * 60)
+
+            df_rows = []
+            for i, cluster in enumerate(clusters):
+                print(f"\nCluster {i + 1} ({len(cluster)} locations):")
+                print("-" * 40)
+
+                if not cluster:
+                    print("  (empty cluster)")
+                    continue
+
+                cluster_boxes = 0
+                for loc in cluster:
+                    name = loc.school_name or loc.contact_name
+                    print(f"  • {name}")
+                    print(f"    {loc.address}")
+                    print(f"    Coords: ({loc.latitude}, {loc.longitude})")
+                    print(f"    Boxes: {loc.num_boxes}")
+                    cluster_boxes += loc.num_boxes
+                    df_rows.append(
+                        {
+                            "name": name,
+                            "long": loc.longitude,
+                            "lat": loc.latitude,
+                            "group": i,
+                        }
+                    )
+
+                print(f"\n  Total boxes in cluster: {cluster_boxes}")
+
+            if df_rows:
+                df = pd.DataFrame(data=df_rows)
+                sns.scatterplot(data=df, x="long", y="lat", hue="group", palette="Set2")
+                plt.title(
+                    f"Generated Sweep clustering for {len(locations)} locations with {len(clusters)} clusters"
+                )
+                plt.xlabel("Longitude")
+                plt.ylabel("Latitude")
+                output_dir = "./app/data"
+                if not os.path.exists(output_dir):
+                    os.makedirs(output_dir)
+                plt.savefig(
+                    os.path.join(output_dir, "sweep_clustering_test.png"),
+                    dpi=300,
+                    bbox_inches="tight",
+                )
+
+            print("\n" + "=" * 60)
+            print("Summary:")
+            print(f"  Total clusters: {len(clusters)}")
+            print(
+                f"  Number of locations in each cluster: {[len(c) for c in clusters]}"
+            )
+            print(f"  Total locations clustered: {sum(len(c) for c in clusters)}")
+
+        except ValueError as e:
+            print(f"Clustering failed: {e}")
+        except Exception as e:
+            print(f"Unexpected error: {e}")
+            import traceback
+
+            traceback.print_exc()
+
+
+if __name__ == "__main__":
+    import asyncio
+
+    asyncio.run(main())

backend/python/app/services/implementations/sweep_clustering.py

@@ -0,0 +1,174 @@
+from __future__ import annotations
+
+import math
+import time
+from typing import TYPE_CHECKING
+
+from app.services.protocols.clustering_algorithm import (
+    ClusteringAlgorithmProtocol,
+)
+
+if TYPE_CHECKING:
+    from app.models.location import Location
+
+
+class LocationLatitudeError(Exception):
+    """Raised when a location doesn't have a latitude."""
+
+    pass
+
+
+class LocationLongitudeError(Exception):
+    """Raised when a location doesn't have a longitude."""
+
+    pass
+
+
+class TimeoutError(Exception):
+    """Raised when an operation exceeds its timeout limit."""
+
+    pass
+
+
+class SweepClusteringAlgorithm(ClusteringAlgorithmProtocol):
+    """Simple mock clustering algorithm that splits locations into clusters.
+
+    This is a pure function with no database interaction. It distributes
+    locations across clusters while respecting max_locations_per_cluster and
+    max_boxes_per_cluster constraints.
+    """
+
+    async def cluster_locations(
+        self,
+        locations: list[Location],
+        num_clusters: int,
+        warehouse_lat: float,
+        warehouse_lon: float,
+        max_locations_per_cluster: int | None = None,
+        max_boxes_per_cluster: int | None = None,
+        timeout_seconds: float | None = None,
+    ) -> list[list[Location]]:
+        """Split locations into clusters while respecting box constraints.
+
+        Args:
+            locations: List of locations to cluster
+            num_clusters: Target number of clusters to create
+            max_locations_per_cluster: Optional maximum number of locations
+                per cluster. If provided, validates that the clustering is
+                possible and raises an error if violated.
+            max_boxes_per_cluster: Optional maximum number of boxes per cluster.
+                If provided, validates that the clustering is possible and
+                raises an error if violated.
+            timeout_seconds: Optional timeout in seconds. Not enforced in this
+                mock implementation.
+
+        Returns:
+            List of clusters, where each cluster is a list of locations
+
+        Raises:
+            ValueError: If the clustering parameters are invalid or cannot
+                be satisfied
+        """
+
+        start_time = time.time()
+
+        def check_timeout() -> None:
+            if timeout_seconds is not None:
+                elapsed = time.time() - start_time
+                if elapsed > timeout_seconds:
+                    raise TimeoutError(
+                        f"Route generation exceeded timeout of {timeout_seconds}s "
+                        f"(elapsed: {elapsed:.2f}s)"
+                    )
+
+        def calculate_angle_from_warehouse(location: Location) -> float | None:
+            if location.latitude is None:
+                raise LocationLatitudeError(
+                    f"Location {location.location_id} is missing latitude."
+                )
+            if location.longitude is None:
+                raise LocationLongitudeError(
+                    f"Location {location.location_id} is missing longitude."
+                )
+            lat_difference = location.latitude - warehouse_lat
+            lon_difference = location.longitude - warehouse_lon
+            return math.atan2(lat_difference, lon_difference) % math.tau
+
+        def calculate_distance_squared(location: Location) -> float | None:
+            if location.latitude is None:
+                raise LocationLatitudeError(
+                    f"Location {location.location_id} is missing latitude."
+                )
+            if location.longitude is None:
+                raise LocationLongitudeError(
+                    f"Location {location.location_id} is missing longitude."
+                )
+            lat_difference = location.latitude - warehouse_lat
+            lon_difference = location.longitude - warehouse_lon
+            return lon_difference**2 + lat_difference**2
+
+        if len(locations) == 0:
+            raise ValueError("locations list cannot be empty")
+
+        if num_clusters < 1:
+            raise ValueError("num_clusters must be at least 1")
+
+        # Calculate base cluster size and validate constraints
+        total_locations = len(locations)
+        base_cluster_size = total_locations // num_clusters
+        remainder = total_locations % num_clusters
+
+        if base_cluster_size == 0:
+            raise ValueError(
+                f"Cannot create {num_clusters} clusters: not enough locations"
+            )
+
+        # The largest cluster will have base_cluster_size + 1 if remainder > 0
+        max_cluster_size = base_cluster_size + (1 if remainder > 0 else 0)
+        if max_locations_per_cluster and max_cluster_size > max_locations_per_cluster:
+            raise ValueError(
+                f"Cannot create {num_clusters} clusters with max "
+                f"{max_locations_per_cluster} locations per cluster. "
+                f"Required cluster size would be up to {max_cluster_size}."
+            )
+
+        # Distribute locations while respecting constraints
+        clusters: list[list[Location]] = []
+        current_location_count = 0
+        current_box_count = 0
+        current_cluster = []
+
+        locations_with_angles = []
+        for location in locations:
+            check_timeout()
+            angle = calculate_angle_from_warehouse(location)
+            distance_squared = calculate_distance_squared(location)
+            locations_with_angles.append((location, angle, distance_squared))
+
+        sorted_locations = sorted(
+            locations_with_angles, key=lambda location: (location[1], location[2])
+        )
+
+        for loc, _angle, _distance in sorted_locations:
+            check_timeout()
+            would_exceed_locations = (
+                current_location_count + 1 > max_locations_per_cluster
+            )
+            would_exceed_boxes = (
+                current_box_count + loc.num_boxes > max_boxes_per_cluster
+            )
+
+            if current_cluster and (would_exceed_locations or would_exceed_boxes):
+                clusters.append(current_cluster)
+                current_cluster = []
+                current_location_count = 0
+                current_box_count = 0
+
+            current_cluster.append(loc)
+            current_location_count += 1
+            current_box_count += loc.num_boxes
+
+        if current_cluster:
+            clusters.append(current_cluster)
+
+        return clusters