Admin Dashboard mit Statistiken: Tierärzte-Anzahl, Gesamtproben und Proben pro Tierarzt

backend/src/main/java/de/svencarstensen/muh/service/AdminStatisticsService.java

@@ -0,0 +1,57 @@
+package de.svencarstensen.muh.service;
+
+import de.svencarstensen.muh.domain.AppUser;
+import de.svencarstensen.muh.domain.Sample;
+import de.svencarstensen.muh.domain.UserRole;
+import de.svencarstensen.muh.repository.AppUserRepository;
+import de.svencarstensen.muh.repository.SampleRepository;
+import de.svencarstensen.muh.web.dto.AdminStatistics;
+import org.springframework.stereotype.Service;
+
+import java.util.List;
+
+@Service
+public class AdminStatisticsService {
+
+    private final AppUserRepository appUserRepository;
+    private final SampleRepository sampleRepository;
+
+    public AdminStatisticsService(AppUserRepository appUserRepository, SampleRepository sampleRepository) {
+        this.appUserRepository = appUserRepository;
+        this.sampleRepository = sampleRepository;
+    }
+
+    public AdminStatistics getStatistics() {
+        // Alle Hauptnutzer (Tierärzte) laden - primaryUser=true und role=CUSTOMER
+        List<AppUser> vets = appUserRepository.findAll().stream()
+                .filter(u -> Boolean.TRUE.equals(u.primaryUser()))
+                .filter(u -> u.role() == UserRole.CUSTOMER)
+                .toList();
+
+        // Alle Proben laden
+        List<Sample> allSamples = sampleRepository.findAll();
+
+        // Proben pro Tierarzt zählen (basierend auf createdByUserCode)
+        List<AdminStatistics.VetSampleStats> samplesPerVet = vets.stream()
+                .map(vet -> {
+                    long sampleCount = allSamples.stream()
+                            .filter(s -> vet.id().equals(s.createdByUserCode()))
+                            .count();
+                    return new AdminStatistics.VetSampleStats(
+                            vet.id(),
+                            vet.displayName(),
+                            vet.companyName(),
+                            sampleCount
+                    );
+                })
+                .filter(s -> s.sampleCount() > 0)
+                .sorted((a, b) -> Long.compare(b.sampleCount(), a.sampleCount()))
+                .toList();
+
+        return new AdminStatistics(
+                vets.size(),
+                allSamples.size(),
+                samplesPerVet
+        );
+    }
+}

backend/src/main/java/de/svencarstensen/muh/web/AdminController.java

@@ -0,0 +1,25 @@
+package de.svencarstensen.muh.web;
+
+import de.svencarstensen.muh.service.AdminStatisticsService;
+import de.svencarstensen.muh.web.dto.AdminStatistics;
+import org.springframework.security.access.prepost.PreAuthorize;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequestMapping("/api/admin")
+@PreAuthorize("hasRole('ADMIN')")
+public class AdminController {
+
+    private final AdminStatisticsService adminStatisticsService;
+
+    public AdminController(AdminStatisticsService adminStatisticsService) {
+        this.adminStatisticsService = adminStatisticsService;
+    }
+
+    @GetMapping("/statistics")
+    public AdminStatistics getStatistics() {
+        return adminStatisticsService.getStatistics();
+    }
+}

backend/src/main/java/de/svencarstensen/muh/web/dto/AdminStatistics.java

@@ -0,0 +1,17 @@
+package de.svencarstensen.muh.web.dto;
+
+import java.util.List;
+
+public record AdminStatistics(
+        long totalVets,
+        long totalSamples,
+        List<VetSampleStats> samplesPerVet
+) {
+    public record VetSampleStats(
+            String userId,
+            String displayName,
+            String companyName,
+            long sampleCount
+    ) {
+    }
+}

frontend/src/pages/AdminDashboardPage.tsx

@@ -1,17 +1,40 @@
+import { useEffect, useState } from "react";
 import { useNavigate } from "react-router-dom";
+import { apiGet } from "../lib/api";
+
+interface VetSampleStats {
+  userId: string;
+  displayName: string;
+  companyName: string | null;
+  sampleCount: number;
+}
+
+interface AdminStatistics {
+  totalVets: number;
+  totalSamples: number;
+  samplesPerVet: VetSampleStats[];
+}
 
 export default function AdminDashboardPage() {
   const navigate = useNavigate();
+  const [stats, setStats] = useState<AdminStatistics | null>(null);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState<string | null>(null);
 
-  const adminModules = [
-    {
-      title: "Benutzer",
-      description: "Freigabe und Sperre von Benutzerkonten",
-      icon: "👥",
-      route: "/admin/benutzer",
-      color: "#5b7ba8",
-    },
-  ];
+  useEffect(() => {
+    async function loadStats() {
+      try {
+        const response = await apiGet<AdminStatistics>("/admin/statistics");
+        setStats(response);
+      } catch (err) {
+        setError((err as Error).message);
+      } finally {
+        setLoading(false);
+      }
+    }
+
+    void loadStats();
+  }, []);
 
   return (
     <div className="page-stack">
@@ -21,41 +44,97 @@ export default function AdminDashboardPage() {
           <p className="eyebrow">Administration</p>
           <h3>Administrator Dashboard</h3>
           <p className="muted-text">
-            Verwalten Sie die Freigabe und Sperre von Benutzerkonten.
+            Übersicht über Tierärzte und Proben im System.
           </p>
         </div>
       </section>
 
+      {error ? (
+        <div className="alert alert--error">{error}</div>
+      ) : null}
+
+      {/* Statistik-Karten */}
+      <section className="metrics-grid admin-metrics">
+        <article className="metric-card metric-card--primary">
+          <span className="metric-card__label">Tierärzte</span>
+          <strong className="metric-card__value--large">
+            {loading ? "..." : stats?.totalVets ?? 0}
+          </strong>
+        </article>
+        <article className="metric-card metric-card--secondary">
+          <span className="metric-card__label">Proben insgesamt</span>
+          <strong className="metric-card__value--large">
+            {loading ? "..." : stats?.totalSamples ?? 0}
+          </strong>
+        </article>
+      </section>
+
+      {/* Tabelle: Proben pro Tierarzt */}
+      <section className="section-card">
+        <div className="section-card__header">
+          <div>
+            <p className="eyebrow">Statistik</p>
+            <h3>Proben pro Tierarzt</h3>
+          </div>
+        </div>
+
+        {loading ? (
+          <div className="empty-state">Statistiken werden geladen...</div>
+        ) : stats?.samplesPerVet.length === 0 ? (
+          <div className="empty-state">Noch keine Proben vorhanden.</div>
+        ) : (
+          <div className="table-shell">
+            <table className="data-table">
+              <thead>
+                <tr>
+                  <th>Tierarzt</th>
+                  <th>Firma</th>
+                  <th style={{ textAlign: "right" }}>Anzahl Proben</th>
+                </tr>
+              </thead>
+              <tbody>
+                {stats?.samplesPerVet.map((vet) => (
+                  <tr key={vet.userId}>
+                    <td>
+                      <strong>{vet.displayName}</strong>
+                    </td>
+                    <td>{vet.companyName ?? "-"}</td>
+                    <td style={{ textAlign: "right" }}>
+                      <span className="sample-count">{vet.sampleCount}</span>
+                    </td>
+                  </tr>
+                ))}
+              </tbody>
+            </table>
+          </div>
+        )}
+      </section>
+
       {/* Admin Module Grid */}
       <section className="admin-modules-section">
         <div className="section-card__header">
           <div>
             <p className="eyebrow">Verwaltung</p>
-            <h3>Verwaltungsmodule</h3>
+            <h3>Verwaltungsmodul</h3>
           </div>
         </div>
 
         <div className="admin-modules-grid">
-          {adminModules.map((module) => (
           <button
-              key={module.route}
             type="button"
             className="admin-module-card"
-              onClick={() => navigate(module.route)}
-              style={{ "--module-color": module.color } as React.CSSProperties}
+            onClick={() => navigate("/admin/benutzer")}
+            style={{ "--module-color": "#5b7ba8" } as React.CSSProperties}
           >
-              <span className="admin-module-card__icon">{module.icon}</span>
+            <span className="admin-module-card__icon">👥</span>
             <div className="admin-module-card__content">
-                <strong>{module.title}</strong>
-                <span className="muted-text">{module.description}</span>
+              <strong>Benutzer</strong>
+              <span className="muted-text">Freigabe und Sperre von Benutzerkonten</span>
             </div>
             <span className="admin-module-card__arrow">→</span>
           </button>
-          ))}
         </div>
       </section>
-
-
     </div>
   );
 }

frontend/src/styles/global.css

@@ -1299,6 +1299,22 @@ a {
   color: var(--muted);
 }
 
+.metric-card--secondary {
+  background: linear-gradient(135deg, rgba(139, 90, 124, 0.2) 0%, rgba(139, 90, 124, 0.05) 100%);
+  border-color: rgba(139, 90, 124, 0.25);
+}
+
+.sample-count {
+  display: inline-block;
+  min-width: 32px;
+  padding: 4px 12px;
+  background: rgba(90, 123, 168, 0.15);
+  border-radius: 16px;
+  font-weight: 600;
+  color: var(--text);
+  text-align: center;
+}
+
 .dialog-backdrop {
   position: fixed;
   inset: 0;