Add better relation support

Logic/Osm/ExtractRelations.ts

@@ -0,0 +1,58 @@
+import State from "../../State";
+
+export interface Relation {
+    id: number,
+    type: "relation"
+    members: {
+        type: ("way" | "node" | "relation"),
+        ref: number,
+        role: string
+    }[],
+    tags: any,
+    // Alias for tags; tags == properties
+    properties: any
+}
+
+export default class ExtractRelations {
+
+    public static RegisterRelations(overpassJson: any) : void{
+        const memberships = ExtractRelations.BuildMembershipTable(ExtractRelations.GetRelationElements(overpassJson))
+        console.log("Assigned memberships: ", memberships)
+        State.state.knownRelations.setData(memberships)
+    }
+    
+    private static GetRelationElements(overpassJson: any): Relation[] {
+        const relations = overpassJson.elements.filter(element => element.type === "relation")
+        for (const relation of relations) {
+            relation.properties = relation.tags
+        }
+        return relations
+    }
+
+    /**
+     * Build a mapping of {memberId --> {role in relation, id of relation} }
+     * @param relations
+     * @constructor
+     */
+    private static BuildMembershipTable(relations: Relation[]): Map<string, { role: string, relation: Relation, }[]> {
+        const memberships = new Map<string, { role: string, relation: Relation }[]>()
+
+        for (const relation of relations) {
+            for (const member of relation.members) {
+
+                const role = {
+                    role: member.role,
+                    relation: relation
+                }
+                const key = member.type + "/" + member.ref
+                if (!memberships.has(key)) {
+                    memberships.set(key, [])
+                }
+                memberships.get(key).push(role)
+            }
+        }
+
+        return memberships
+    }
+
+}

Logic/Osm/Overpass.ts

@@ -1,7 +1,8 @@
 import * as $ from "jquery"
 import * as OsmToGeoJson from "osmtogeojson";
 import Bounds from "../../Models/Bounds";
-import {TagsFilter} from "../TagsFilter";
+import {TagsFilter} from "../Tags/TagsFilter";
+import ExtractRelations from "./ExtractRelations";
 
 /**
  * Interfaces overpass to get all the latest data
@@ -38,9 +39,9 @@ export class Overpass {
                     return;
                 }
 
+                ExtractRelations.RegisterRelations(json)
                 // @ts-ignore
                 const geojson = OsmToGeoJson.default(json);
-                console.log("Received geojson", geojson)
                 const osmTime = new Date(json.osm3s.timestamp_osm_base);
                 continuation(geojson, osmTime);