ShopSolution-backend/Webshop.Application/Services/Admin/AdminSupplierService.cs

// src/Webshop.Application/Services/Admin/AdminSupplierService.cs
using Webshop.Domain.Entities;
using Webshop.Domain.Interfaces; // Wichtig für ISupplierRepository
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Webshop.Application.DTOs.Suppliers;
using Webshop.Application.Services.Admin.Interfaces;

namespace Webshop.Application.Services.Admin
{
    // Implementiert das Interface, das der Controller erwartet
    public class AdminSupplierService : IAdminSupplierService
    {
        private readonly ISupplierRepository _supplierRepository;

        // Lässt sich das Repository per Dependency Injection geben
        public AdminSupplierService(ISupplierRepository supplierRepository)
        {
            _supplierRepository = supplierRepository;
        }

        public async Task<IEnumerable<SupplierDto>> GetAllSuppliersAsync()
        {
            var suppliers = await _supplierRepository.GetAllSuppliersAsync();
            // Mappt die Entity-Liste zu einer DTO-Liste für die API
            return suppliers.Select(s => new SupplierDto
            {
                Id = s.Id,
                Name = s.Name,
                ContactPerson = s.ContactPerson,
                Email = s.Email,
                PhoneNumber = s.PhoneNumber,
                AddressId = s.AddressId,
                Notes = s.Notes
            });
        }

        public async Task<SupplierDto?> GetSupplierByIdAsync(Guid id)
        {
            var supplier = await _supplierRepository.GetSupplierByIdAsync(id);
            if (supplier == null) return null;

            // Mappt die gefundene Entity zu einem DTO
            return new SupplierDto
            {
                Id = supplier.Id,
                Name = supplier.Name,
                ContactPerson = supplier.ContactPerson,
                Email = supplier.Email,
                PhoneNumber = supplier.PhoneNumber,
                AddressId = supplier.AddressId,
                Notes = supplier.Notes
            };
        }

        public async Task<SupplierDto> CreateSupplierAsync(SupplierDto supplierDto)
        {
            // Wandelt das DTO von der API in eine Datenbank-Entity um
            var supplier = new Supplier
            {
                Name = supplierDto.Name,
                ContactPerson = supplierDto.ContactPerson,
                Email = supplierDto.Email,
                PhoneNumber = supplierDto.PhoneNumber,
                AddressId = supplierDto.AddressId,
                Notes = supplierDto.Notes
            };

            await _supplierRepository.AddSupplierAsync(supplier);

            // Gibt ein DTO mit der neu generierten ID zurück
            supplierDto.Id = supplier.Id;
            return supplierDto;
        }

        public async Task<bool> UpdateSupplierAsync(Guid id, SupplierDto supplierDto)
        {
            var existingSupplier = await _supplierRepository.GetSupplierByIdAsync(id);
            if (existingSupplier == null)
            {
                return false; // Konnte nicht gefunden werden
            }

            // Aktualisiert die Daten der gefundenen Entity
            existingSupplier.Name = supplierDto.Name;
            existingSupplier.ContactPerson = supplierDto.ContactPerson;
            existingSupplier.Email = supplierDto.Email;
            existingSupplier.PhoneNumber = supplierDto.PhoneNumber;
            existingSupplier.AddressId = supplierDto.AddressId;
            existingSupplier.Notes = supplierDto.Notes;

            await _supplierRepository.UpdateSupplierAsync(existingSupplier);
            return true;
        }

        public async Task<bool> DeleteSupplierAsync(Guid id)
        {
            var supplier = await _supplierRepository.GetSupplierByIdAsync(id);
            if (supplier == null)
            {
                return false; // Konnte nicht gefunden werden
            }

            await _supplierRepository.DeleteSupplierAsync(id);
            return true;
        }
    }
}