Subs union to server side

imports/ui/components/Maps/SubsUnion/Unify.js

@@ -0,0 +1,48 @@
+import { check } from 'meteor/check';
+import LGeo from 'leaflet-geodesy';
+import tunion from '@turf/union';
+import ttrunc from '@turf/truncate';
+
+// https://stackoverflow.com/questions/35394577/leaflet-js-union-merge-circles
+const truncOptions = { precision: 6, coordinates: 2 };
+
+const unify = (polyList) => {
+  let unionTemp;
+  for (let i = 0; i < polyList.length; i += 1) {
+    const pol = polyList[i].toGeoJSON();
+    const cleanPol = ttrunc(pol, truncOptions);
+    if (i === 0) {
+      unionTemp = cleanPol;
+    } else {
+      unionTemp = ttrunc(tunion(unionTemp, cleanPol), truncOptions);
+    }
+  }
+  return unionTemp;
+};
+
+const calcUnion = (subs, group, decorated) => {
+  const unionGroup = group;
+  const copts = {
+    parts: 144
+  };
+  subs.forEach((osub) => {
+    try {
+      if (osub.location && osub.location.lat && osub.location.lon && osub.distance) {
+        check(osub.location.lon, Number);
+        check(osub.location.lat, Number);
+        check(osub.distance, Number);
+        const dsub = decorated(osub);
+        const circle = LGeo.circle([dsub.location.lat, dsub.location.lon], dsub.distance * 1000, copts);
+        circle.addTo(unionGroup);
+      } else {
+        console.error(`Wrong subscription ${JSON.stringify(osub)}`);
+      }
+    } catch (e) {
+      console.error(e, `Wrong subscription trying to make union ${JSON.stringify(osub)}`);
+    }
+  });
+  const unionJson = unify(unionGroup.getLayers());
+  return [unionJson, unionGroup.getBounds()];
+};
+
+export default calcUnion;