feat(1-3260): impl fake interface

src/lib/features/traffic-data-usage/fake-traffic-data-usage-store.ts

@@ -1,9 +1,15 @@
 import type {
     IStatTrafficUsageKey,
     IStatTrafficUsage,
+    IStatMonthlyTrafficUsage,
 } from './traffic-data-usage-store-type';
 import type { ITrafficDataUsageStore } from '../../types';
-import { isSameMonth, parse } from 'date-fns';
+import {
+    differenceInCalendarMonths,
+    format,
+    isSameMonth,
+    parse,
+} from 'date-fns';
 
 export class FakeTrafficDataUsageStore implements ITrafficDataUsageStore {
     private trafficData: IStatTrafficUsage[] = [];
@@ -50,4 +56,37 @@ export class FakeTrafficDataUsageStore implements ITrafficDataUsageStore {
             isSameMonth(data.day, periodDate),
         );
     }
+
+    async getTrafficDataForMonthRange(
+        monthsBack: number,
+    ): Promise<IStatMonthlyTrafficUsage[]> {
+        const now = new Date();
+
+        const data: { [key: string]: IStatMonthlyTrafficUsage } =
+            this.trafficData
+                .filter(
+                    (entry) =>
+                        differenceInCalendarMonths(now, entry.day) <=
+                        monthsBack,
+                )
+                .reduce((acc, entry) => {
+                    const month = format(entry.day, 'yyyy-MM');
+                    const key = `${month}-${entry.trafficGroup}-${entry.statusCodeSeries}`;
+
+                    if (acc[key]) {
+                        acc[key].count += entry.count;
+                    } else {
+                        acc[key] = {
+                            month,
+                            trafficGroup: entry.trafficGroup,
+                            statusCodeSeries: entry.statusCodeSeries,
+                            count: entry.count,
+                        };
+                    }
+
+                    return acc;
+                }, {});
+
+        return Object.values(data);
+    }
 }