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Webshop.Api/Controllers/Admin/AdminSuppliersController.cs

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+// src/Webshop.Api/Controllers/Admin/AdminSuppliersController.cs
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using Webshop.Application.DTOs; // SupplierDto
+using Webshop.Application.Services.Admin; // AdminSupplierService
+using System.Collections.Generic; // F<>r IEnumerable
+using System.Threading.Tasks; // F<>r Task
+
+namespace Webshop.Api.Controllers.Admin
+{
+    [ApiController]
+    [Route("api/v1/admin/[controller]")] // z.B. /api/v1/admin/suppliers
+    [Authorize(Roles = "Admin")] // Nur Admins
+    public class AdminSuppliersController : ControllerBase
+    {
+        // HIER MUSS NUR EINE EINZIGE DEKLARATION STEHEN
+        private readonly AdminSupplierService _adminSupplierService;
+
+        public AdminSuppliersController(AdminSupplierService adminSupplierService)
+        {
+            _adminSupplierService = adminSupplierService;
+        }
+
+        [HttpGet]
+        public async Task<ActionResult<IEnumerable<SupplierDto>>> GetAllSuppliers()
+        {
+            var suppliers = await _adminSupplierService.GetAllSuppliersAsync();
+            return Ok(suppliers);
+        }
+
+        [HttpPost]
+        public async Task<ActionResult<SupplierDto>> CreateSupplier([FromBody] SupplierDto supplierDto)
+        {
+            if (!ModelState.IsValid) return BadRequest(ModelState);
+            var createdSupplier = await _adminSupplierService.CreateSupplierAsync(supplierDto);
+            return CreatedAtAction(nameof(GetSupplierById), new { id = createdSupplier.Id }, createdSupplier);
+        }
+
+        [HttpGet("{id}")]
+        public async Task<ActionResult<SupplierDto>> GetSupplierById(Guid id)
+        {
+            var supplier = await _adminSupplierService.GetSupplierByIdAsync(id);
+            if (supplier == null) return NotFound();
+            return Ok(supplier);
+        }
+    }
+}