Merge pull request #548 from ReliefApplications/feat/AB#58618_Move_all_GIS_random_generation_to_the_back_end

Feat/ab#58618 move all gis random generation to the back end

Author: AntoineRelief

src/utils/geojson/generateGeoJson.ts

@@ -0,0 +1,119 @@
+// import { getRandomIcon } from '../const/fa-icons';
+// import { MarkerIconOptions } from '../utils/create-div-icon';
+
+/** Represents the types of geometries that can be generated */
+type FeatureTypes = 'Point' | 'Polygon' | 'LineString';
+
+/** Options for generating random features */
+type CollectionGeneratorOptions = {
+  [key in FeatureTypes]?: {
+    generateProperties: () => any;
+    probability?: number;
+    numCoordinates?: number;
+    maxDistance?: number;
+    minDistance?: number;
+  };
+} & {
+  numFeatures: number;
+};
+
+/** Default max distance in degrees */
+const DEFAULT_MAX_DISTANCE = 15;
+
+/** Default min distance in degrees */
+const DEFAULT_MIN_DISTANCE = 5;
+
+/**
+ * Returns a random item from the given options based on the weights provided.
+ *
+ * @param options - Array of options to choose from
+ * @param weights - Array of weights for each option
+ * @returns The randomly selected item from the options array
+ */
+const weightedRandom = (
+  options: FeatureTypes[],
+  weights: { [key in FeatureTypes]: number }
+) => {
+  let sum = 0;
+  const keys = Object.keys(weights) as FeatureTypes[];
+  for (const key of keys) {
+    sum += weights[key];
+  }
+
+  const randomNum = Math.random() * sum;
+  let weightSum = 0;
+  for (const key of options) {
+    weightSum += weights[key];
+    if (randomNum <= weightSum) {
+      return key;
+    }
+  }
+  return options[options.length - 1];
+};
+
+/**
+ * Generates random features based on the specified options
+ *
+ * @param options Options for generating random features
+ * @returns Array of generated features
+ */
+export const generateGeoJson = (options: CollectionGeneratorOptions) => {
+  const featureTypes = Object.keys(options) as FeatureTypes[];
+  const typeProbabilities = featureTypes.reduce((probabilities, type) => {
+    const prob = options[type]?.probability;
+    if (prob !== undefined) {
+      probabilities[type] = prob;
+    }
+    return probabilities;
+  }, {} as { [key in FeatureTypes]: number });
+
+  const features = [];
+  for (let i = 0; i < options.numFeatures; i++) {
+    const type = weightedRandom(featureTypes, typeProbabilities);
+    const option = options[type];
+    if (!option) continue;
+    const properties = option.generateProperties();
+    const maxDistance = option.maxDistance || DEFAULT_MAX_DISTANCE;
+    const minDistance = option.minDistance || DEFAULT_MIN_DISTANCE;
+    let coordinates;
+    switch (type) {
+      case 'Point':
+        coordinates = [Math.random() * 360 - 180, Math.random() * 180 - 90];
+        break;
+      case 'Polygon':
+      case 'LineString':
+        const numCoordinates = options[type]?.numCoordinates || 3;
+        coordinates = [];
+        let previousLat = 0;
+        let previousLng = 0;
+        for (let j = 0; j < numCoordinates; j++) {
+          let lat = Math.random() * 180 - 90;
+          let lng = Math.random() * 360 - 180;
+          if (j !== 0) {
+            let latDifference = Math.abs(previousLat - lat);
+            let lngDifference = Math.abs(previousLng - lng);
+            while (
+              latDifference > maxDistance ||
+              lngDifference > maxDistance ||
+              latDifference < minDistance ||
+              lngDifference < minDistance
+            ) {
+              lat = Math.random() * 180 - 90;
+              lng = Math.random() * 360 - 180;
+              latDifference = Math.abs(previousLat - lat);
+              lngDifference = Math.abs(previousLng - lng);
+            }
+          }
+          previousLat = lat;
+          previousLng = lng;
+          coordinates.push([lat, lng]);
+        }
+        if (type === 'Polygon') {
+          coordinates = [coordinates];
+        }
+        break;
+    }
+    features.push({ type, properties, coordinates });
+  }
+  return features;
+};