fix issue #49 (#52)

* remove color index from code
use different approach

fix issue #49

* remove unneeded space
change var to let

* add 2 more tests to check correct color choice behaviour after deleting anomalies

* use more descriptive word in text description

src/controllers/analytic_controller.ts

@@ -37,11 +37,8 @@ export class AnalyticController {
   private _savingNewAnalyticUnit: boolean = false;
   private _tempIdCounted: number = -1;
   private _graphLocked: boolean = false;
-  private _currentColorIndex: number = 0;
-
   private _statusRunners: Set<AnalyticUnitId> = new Set<AnalyticUnitId>();
 
-
   constructor(private _panelObject: any, private _analyticService: AnalyticService, private _emitter: Emitter) {
     if(_panelObject.anomalyTypes === undefined) {
       _panelObject.anomalyTypes = [];
@@ -50,7 +47,6 @@ export class AnalyticController {
     this._labelingDataDeletedSegments = new SegmentArray<AnalyticSegment>();
     this._analyticUnitsSet = new AnalyticUnitsSet(this._panelObject.anomalyTypes);
     this.analyticUnits.forEach(a => this.runEnabledWaiter(a));
-    this._currentColorIndex = this._panelObject.anomalyTypes.length % ANALYTIC_UNIT_COLORS.length;
   }
 
   getSegmentsSearcher(): AnalyticSegmentsSearcher {
@@ -72,9 +68,13 @@ export class AnalyticController {
     this._newAnalyticUnit = new AnalyticUnit();
     this._creatingNewAnalyticType = true;
     this._savingNewAnalyticUnit = false;
-    this._newAnalyticUnit.color = ANALYTIC_UNIT_COLORS[this._currentColorIndex];
-    this._currentColorIndex++;
-    this._currentColorIndex %= ANALYTIC_UNIT_COLORS.length;
+    if (this.analyticUnits.length === 0) {
+      this._newAnalyticUnit.color = ANALYTIC_UNIT_COLORS[0];
+    } else {
+      let colorIndex = ANALYTIC_UNIT_COLORS.indexOf(_.last(this.analyticUnits).color) + 1;
+      colorIndex %= ANALYTIC_UNIT_COLORS.length;
+      this._newAnalyticUnit.color = ANALYTIC_UNIT_COLORS[colorIndex];
+    }
   }
 
   async saveNew(metricExpanded: MetricExpanded, datasourceRequest: DatasourceRequest, panelId: number) {

tests/analyticController.jest.ts

@@ -3,6 +3,7 @@ import { MetricExpanded } from '../src/models/metric';
 import { DatasourceRequest } from '../src/models/datasource';
 
 import { analyticController } from './setup_tests';
+import { AnalyticUnit } from '../src/models/analytic_unit';
 
 
 describe('AnalyticController', function () {
@@ -25,6 +26,21 @@ describe('AnalyticController', function () {
     }
   });
 
+  it('should set different color to newly created Analytic Unit, afer NOT last AU was deleted', async function() {
+    let auArray = analyticController.analyticUnits;
+    analyticController.createNew();
+    await analyticController.saveNew({} as MetricExpanded, {} as DatasourceRequest, 1);
+    expect(auArray[auArray.length - 2].panelObject.color).not.toBe(auArray[auArray.length - 1].panelObject.color);
+  });
+
+  it('should set different color to newly created Analytic Unit, afer LAST AU was deleted', async function () {
+    let auArray = analyticController.analyticUnits;
+    auArray.splice(-1, 1);
+    analyticController.createNew();
+    await analyticController.saveNew({} as MetricExpanded, {} as DatasourceRequest, 1);
+    expect(auArray[auArray.length - 2].panelObject.color).not.toBe(auArray[auArray.length - 1].panelObject.color);
+  });
+
   it('should change color on choosing from palette', function () {
     analyticController.onAnalyticUnitColorChange('1', 'red');
     expect(analyticController.analyticUnits[0].color).toBe('red');