GUI2 Added selection of background maps

Change-Id: I88ee69fe2ff24bb1b4b3fe633b04f2f1778f3a82
diff --git a/web/gui2/src/main/webapp/app/view/topology/layer/mapsvg/mapsvg.component.ts b/web/gui2/src/main/webapp/app/view/topology/layer/mapsvg/mapsvg.component.ts
index 2de6c12..a10cf4c 100644
--- a/web/gui2/src/main/webapp/app/view/topology/layer/mapsvg/mapsvg.component.ts
+++ b/web/gui2/src/main/webapp/app/view/topology/layer/mapsvg/mapsvg.component.ts
@@ -13,18 +13,206 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import { Component, OnInit } from '@angular/core';
+import {
+    Component,
+    Input,
+    OnChanges,
+    SimpleChanges
+} from '@angular/core';
+import { MapObject } from '../maputils';
+import {LogService} from 'gui2-fw-lib';
+import {HttpClient} from '@angular/common/http';
+import * as d3 from 'd3';
+import * as topojson from 'topojson-client';
+
+const BUNDLED_URL_PREFIX = 'data/map/';
+
+/**
+ * Model of the transform attribute of a topojson file
+ */
+interface TopoDataTransform {
+    scale: number[];
+    translate: number[];
+}
+
+/**
+ * Model of the Generator setting for D3 GEO
+ */
+interface GeneratorSettings {
+    objectTag: string;
+    projection: Object;
+    logicalSize: number;
+    mapFillScale: number;
+}
+
+/**
+ * Model of the Path Generator
+ */
+interface PathGenerator {
+    geodata: FeatureCollection;
+    pathgen: (Feature) => string;
+    settings: GeneratorSettings;
+}
+
+/**
+ * Model of the Feature returned prom topojson library
+ */
+interface Feature {
+    geometry: Object;
+    id: string;
+    properties: Object;
+    type: string;
+}
+
+/**
+ * Model of the Features Collection returned by the topojson.features function
+ */
+interface FeatureCollection {
+    type: string;
+    features: Feature[];
+}
+
+/**
+ * Model of the topojson file
+ */
+interface TopoData {
+    type: string; // Usually "Topology"
+    objects: Object; // Can be a list of countries or individual countries
+    arcs: number[][][]; // Coordinates
+    bbox: number[]; // Bounding box
+    transform: TopoDataTransform; // scale and translate
+}
+
+/**
+ * Default settings for the path generator for TopoJson
+ */
+const DEFAULT_GEN_SETTINGS: GeneratorSettings = <GeneratorSettings>{
+    objectTag: 'states',
+    projection: d3.geoMercator(),
+    logicalSize: 1000,
+    mapFillScale: .95,
+};
 
 @Component({
     selector: '[onos-mapsvg]',
     templateUrl: './mapsvg.component.html',
     styleUrls: ['./mapsvg.component.css']
 })
-export class MapSvgComponent implements OnInit {
+export class MapSvgComponent implements  OnChanges {
+    @Input() map: MapObject = <MapObject>{id: 'none'};
 
-    constructor() { }
+    cache = new Map<string, TopoData>();
+    topodata: TopoData;
+    mapPathGenerator: PathGenerator;
 
-    ngOnInit() {
+    constructor(
+        private log: LogService,
+        private httpClient: HttpClient,
+    ) {
+        this.log.debug('MapSvgComponent constructed');
     }
 
+    static getUrl(id: string): string {
+        if (id && id[0] === '*') {
+            return BUNDLED_URL_PREFIX + id.slice(1) + '.topojson';
+        }
+        return id + '.topojson';
+    }
+
+    ngOnChanges(changes: SimpleChanges): void {
+        this.log.debug('Change detected', changes);
+        if (changes['map']) {
+            const map: MapObject = <MapObject>(changes['map'].currentValue);
+            if (map.id) {
+                if (this.cache.get(map.id)) {
+                    this.topodata = this.cache.get(map.id);
+                } else {
+                    this.httpClient
+                        .get(MapSvgComponent.getUrl(map.filePath))
+                        .subscribe((topoData: TopoData) => {
+                            this.mapPathGenerator = this.handleTopoJson(map, topoData);
+                            this.log.debug('Path Generated for', map.id,
+                                'from', MapSvgComponent.getUrl(map.filePath));
+                        });
+                }
+            }
+        }
+    }
+
+    /**
+     * Wrapper for the path generator function
+     * @param feature The county or state within the map
+     */
+    pathGenerator(feature: Feature): string {
+        return this.mapPathGenerator.pathgen(feature);
+    }
+
+    /**
+     * Handle the topojson file stream as it arrives back from the server
+     *
+     * The topojson library converts the topojson file in to a FeatureCollection
+     * d3.geo then further converts this in to a Path
+     *
+     * @param map The Map chosen in the GUI
+     * @param topoData The data in the TopoJson file
+     */
+    handleTopoJson(map: MapObject, topoData: TopoData): PathGenerator {
+        this.topodata = topoData;
+        this.cache.set(map.id, topoData);
+        this.log.debug('Map retrieved', topoData);
+
+        const topoObject = topoData.objects[map.id];
+        const geoData: FeatureCollection = <FeatureCollection>topojson.feature(topoData, topoObject);
+        this.log.debug('Map retrieved', topoData, geoData);
+
+        const settings: GeneratorSettings = Object.assign({}, DEFAULT_GEN_SETTINGS);
+        const path = d3.geoPath().projection(settings.projection);
+        this.rescaleProjection(
+            settings.projection,
+            settings.mapFillScale,
+            settings.logicalSize,
+            path,
+            geoData);
+        this.log.debug('Scale adjusted');
+
+        return <PathGenerator>{
+            geodata: geoData,
+            pathgen: path,
+            settings: settings
+        };
+    }
+
+    /**
+     * Adjust projection scale and translation to fill the view
+     * with the map
+     * @param proj
+     * @param mfs
+     * @param dim
+     * @param path
+     * @param geoData
+     * @param adjustScale
+     */
+    rescaleProjection(proj: any, mfs: number, dim: number, path: any,
+                      geoData: FeatureCollection, adjustScale: number = 1.0) {
+        // start with unit scale, no translation..
+        proj.scale(1).translate([0, 0]);
+
+        // figure out dimensions of map data..
+        const b = path.bounds(geoData);
+        const x1 = b[0][0];
+        const y1 = b[0][1];
+        const x2 = b[1][0];
+        const y2 = b[1][1];
+        const dx = x2 - x1;
+        const dy = y2 - y1;
+        const x = (x1 + x2) / 2;
+        const y = (y1 + y2) / 2;
+
+        // size map to 95% of minimum dimension to fill space..
+        const s = (mfs / Math.min(dx / dim, dy / dim)) * adjustScale;
+        const t = [dim / 2 - s * x, dim / 2 - s * y];
+
+        // set new scale, translation on the projection..
+        proj.scale(s).translate(t);
+    }
 }