More work on splitting roads, WIP; refactoring tests

Logic/FeatureSource/Sources/NewGeometryFromChangesFeatureSource.ts

@@ -0,0 +1,90 @@
+import {Changes} from "../../Osm/Changes";
+import {OsmNode, OsmRelation, OsmWay} from "../../Osm/OsmObject";
+import FeatureSource from "../FeatureSource";
+import {UIEventSource} from "../../UIEventSource";
+import {ChangeDescription} from "../../Osm/Actions/ChangeDescription";
+
+export class NewGeometryFromChangesFeatureSource implements FeatureSource {
+    // This class name truly puts the 'Java' into 'Javascript'
+    
+    /**
+     * A feature source containing exclusively new elements
+     */
+    public readonly features: UIEventSource<{ feature: any; freshness: Date }[]> = new UIEventSource<{ feature: any; freshness: Date }[]>([]);
+    public readonly name: string = "newFeatures";
+
+    constructor(changes: Changes) {
+
+        const seenChanges = new Set<ChangeDescription>();
+        const features = this.features.data;
+        const self = this;
+
+        changes.pendingChanges
+            .map(changes => changes.filter(ch =>
+                // only new objects allowed
+                ch.id < 0 &&
+                // The change is an update to the object (e.g. tags or geometry) - not the actual create
+                ch.changes !== undefined &&
+                // If tags is undefined, this is probably a new point that is part of a split road
+                ch.tags !== undefined &&
+                // Already handled
+                !seenChanges.has(ch)))
+            .addCallbackAndRunD(changes => {
+
+                if (changes.length === 0) {
+                    return;
+                }
+
+                const now = new Date();
+
+                function add(feature) {
+                    feature.id = feature.properties.id
+                    features.push({
+                        feature: feature,
+                        freshness: now
+                    })
+                    console.warn("Added a new feature: ", JSON.stringify(feature))
+                }
+
+                for (const change of changes) {
+                    seenChanges.add(change)
+                    try {
+                        const tags = {}
+                        for (const kv of change.tags) {
+                            tags[kv.k] = kv.v
+                        }
+                        tags["id"] = change.type+"/"+change.id
+                        switch (change.type) {
+                            case "node":
+                                const n = new OsmNode(change.id)
+                                n.tags = tags
+                                n.lat = change.changes["lat"]
+                                n.lon = change.changes["lon"]
+                                const geojson = n.asGeoJson()
+                                add(geojson)
+                                break;
+                            case "way":
+                                const w = new OsmWay(change.id)
+                                w.tags = tags
+                                w.nodes = change.changes["nodes"]
+                                w.coordinates = change.changes["coordinates"].map(coor => coor.reverse())
+                                add(w.asGeoJson())
+                                break;
+                            case "relation":
+                                const r = new OsmRelation(change.id)
+                                r.tags = tags
+                                r.members = change.changes["members"]
+                                add(r.asGeoJson())
+                                break;
+                        }
+                    } catch (e) {
+                        console.error("Could not generate a new geometry to render on screen for:", e)
+                    }
+
+                }
+                
+                self.features.ping()
+            })
+    }
+
+}