feat(frontend): add metering data chart to dashboard overview with ECharts

eeg_frontend/src/app/pages/dashboard-overview/dashboard-overview.html

@@ -27,6 +27,7 @@
     </div>
   </div>
 } @else if (userStats(); as stats) {
+  <div class="space-y-6">
     <div class="grid grid-cols-1 sm:grid-cols-3 gap-6">
       <div class="bg-white rounded-2xl shadow-sm border border-slate-200 p-6">
         <p class="text-sm text-slate-500">Meine Zählpunkte</p>
@@ -41,4 +42,37 @@
         <p class="text-3xl font-bold text-slate-800 mt-2">{{ stats.pendingMemberships }}</p>
       </div>
     </div>
+
+    @if (meteringData(); as data) {
+      @if (data.meteringPoints.length > 0) {
+        <div class="bg-white rounded-2xl shadow-sm border border-slate-200 p-6">
+          <div class="flex justify-between items-center mb-4">
+            <h2 class="text-lg font-semibold text-slate-800">Verbrauch & Erzeugung</h2>
+            <div class="flex gap-2">
+              <button
+                (click)="setRange(7)"
+                [class]="selectedDays() === 7 ? 'px-3 py-2 text-sm rounded-lg bg-emerald-600 text-white' : 'px-3 py-2 text-sm rounded-lg border border-slate-300 hover:bg-slate-50'">
+                7 Tage
+              </button>
+              <button
+                (click)="setRange(30)"
+                [class]="selectedDays() === 30 ? 'px-3 py-2 text-sm rounded-lg bg-emerald-600 text-white' : 'px-3 py-2 text-sm rounded-lg border border-slate-300 hover:bg-slate-50'">
+                30 Tage
+              </button>
+              <button
+                (click)="setRange(90)"
+                [class]="selectedDays() === 90 ? 'px-3 py-2 text-sm rounded-lg bg-emerald-600 text-white' : 'px-3 py-2 text-sm rounded-lg border border-slate-300 hover:bg-slate-50'">
+                90 Tage
+              </button>
+            </div>
+          </div>
+          @if (chartOptions()) {
+            <div echarts [options]="chartOptions()" class="h-[400px]"></div>
+          } @else {
+            <p class="text-slate-500 text-center py-8">Keine Daten im ausgewählten Zeitraum vorhanden.</p>
+          }
+        </div>
+      }
+    }
+  </div>
 }

eeg_frontend/src/app/pages/dashboard-overview/dashboard-overview.ts

@@ -1,10 +1,12 @@
 import {Component, inject, OnInit, signal} from '@angular/core';
+import {NgxEchartsDirective} from 'ngx-echarts';
 import {AuthService} from '../../services/auth';
-import {AdminStats, DashboardService, UserStats} from '../../services/dashboard';
+import {AdminStats, DashboardService, MeteringDataOverview, UserStats} from '../../services/dashboard';
 
 @Component({
   selector: 'app-dashboard-overview',
   standalone: true,
+  imports: [NgxEchartsDirective],
   templateUrl: './dashboard-overview.html'
 })
 export class DashboardOverview implements OnInit {
@@ -17,6 +19,10 @@ export class DashboardOverview implements OnInit {
   isLoading = signal(true);
   error = signal<string | null>(null);
 
+  meteringData = signal<MeteringDataOverview | null>(null);
+  chartOptions = signal<any>(null);
+  selectedDays = signal(30);
+
   ngOnInit() {
     if (this.role === 'ADMIN') {
       this.dashboardService.getAdminStats().subscribe({
@@ -28,7 +34,11 @@ export class DashboardOverview implements OnInit {
       });
     } else {
       this.dashboardService.getUserStats().subscribe({
-        next: stats => { this.userStats.set(stats); this.isLoading.set(false); },
+        next: stats => {
+          this.userStats.set(stats);
+          this.isLoading.set(false);
+          this.loadMeteringData();
+        },
         error: () => {
           this.isLoading.set(false);
           this.error.set('Fehler beim Laden der Statistiken.');
@@ -36,4 +46,72 @@ export class DashboardOverview implements OnInit {
       });
     }
   }
+
+  setRange(days: number) {
+    this.selectedDays.set(days);
+    this.loadMeteringData();
+  }
+
+  private loadMeteringData() {
+    const to = new Date();
+    const from = new Date();
+    from.setDate(from.getDate() - this.selectedDays());
+
+    const fromStr = from.toISOString();
+    const toStr = to.toISOString();
+
+    this.dashboardService.getMeteringDataOverview(fromStr, toStr).subscribe({
+      next: (data) => {
+        this.meteringData.set(data);
+        this.buildChartOptions(data);
+      },
+      error: () => {}
+    });
+  }
+
+  private buildChartOptions(data: MeteringDataOverview) {
+    if (!data || data.timeSeries.length === 0) {
+      this.chartOptions.set(null);
+      return;
+    }
+
+    const dates = data.timeSeries.map(e => {
+      const d = new Date(e.timestamp);
+      return d.toLocaleDateString('de-AT', {day: '2-digit', month: '2-digit'});
+    });
+
+    const series = data.meteringPoints.map(mp => ({
+      name: `${mp.atNumber.slice(-8)} (${mp.type})`,
+      type: 'bar' as const,
+      stack: 'total',
+      data: data.timeSeries.map(e => e.values[mp.atNumber] || 0),
+      itemStyle: {color: mp.type === 'CONSUMER' ? '#3b82f6' : '#22c55e'}
+    }));
+
+    this.chartOptions.set({
+      tooltip: {
+        trigger: 'axis',
+        formatter: (params: any[]) => {
+          const label = params[0]?.axisValue || '';
+          let html = `<strong>${label}</strong><br/>`;
+          params.forEach((p: any) => {
+            html += `${p.marker} ${p.seriesName}: ${p.value?.toFixed(2)} kWh<br/>`;
+          });
+          return html;
+        }
+      },
+      legend: {
+        data: series.map(s => s.name),
+        top: 0
+      },
+      grid: {left: '3%', right: '4%', bottom: '3%', containLabel: true},
+      xAxis: {
+        type: 'category',
+        data: dates,
+        axisLabel: {rotate: dates.length > 15 ? 45 : 0}
+      },
+      yAxis: {type: 'value', name: 'kWh'},
+      series
+    });
+  }
 }

eeg_frontend/src/app/services/auth.ts

@@ -42,4 +42,15 @@ export class AuthService {
     localStorage.clear();
     this.isLoggedInSubject.next(false);
   }
+
+  getCurrentUserId(): string | null {
+    const token = localStorage.getItem('token');
+    if (!token) return null;
+    try {
+      const payload = JSON.parse(atob(token.split('.')[1]));
+      return payload.userId || null;
+    } catch {
+      return null;
+    }
+  }
 }

eeg_frontend/src/app/services/dashboard.ts

@@ -1,5 +1,5 @@
 import {inject, Injectable} from '@angular/core';
-import {HttpClient} from '@angular/common/http';
+import {HttpClient, HttpParams} from '@angular/common/http';
 import {Observable} from 'rxjs';
 import {environment} from '../../environments/environment';
 
@@ -16,6 +16,23 @@ export interface UserStats {
   pendingMemberships: number;
 }
 
+export interface MeteringPointSummary {
+  id: string;
+  atNumber: string;
+  type: string;
+  totalKwh: number;
+}
+
+export interface TimeSeriesEntry {
+  timestamp: string;
+  values: { [atNumber: string]: number };
+}
+
+export interface MeteringDataOverview {
+  meteringPoints: MeteringPointSummary[];
+  timeSeries: TimeSeriesEntry[];
+}
+
 @Injectable({providedIn: 'root'})
 export class DashboardService {
   private http = inject(HttpClient);
@@ -28,4 +45,11 @@ export class DashboardService {
   getUserStats(): Observable<UserStats> {
     return this.http.get<UserStats>(`${this.apiUrl}/user`);
   }
+
+  getMeteringDataOverview(from: string, to: string): Observable<MeteringDataOverview> {
+    const params = new HttpParams()
+      .set('from', from)
+      .set('to', to);
+    return this.http.get<MeteringDataOverview>(`${this.apiUrl}/user/metering-data/overview`, {params});
+  }
 }