feat: CodeGenerator-Service mit Konfigurationsunterstützung implementiert

- CodeGenerator-Service erstellt, der zufällige Codes basierend auf einem konfigurierbaren Zeichensatz generiert.
- IOptions<CodeGeneratorConfig> für DI-Injektion der Konfigurationseinstellungen integriert.
- Lazy-Initialisierung für statische Instanz des CodeGenerators hinzugefügt.
- Validierung hinzugefügt, um sicherzustellen, dass die Code-Länge größer als null ist.
- Geplante zukünftige Verbesserung: Random als Singleton injizieren, um die Multithreading-Performance zu verbessern.

EnvelopeGenerator.Application/Configurations/CodeGeneratorConfig.cs

@@ -0,0 +1,7 @@
+namespace EnvelopeGenerator.Application.Configurations
+{
+    public class CodeGeneratorConfig
+    {
+        public string CharPool { get; init; } = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
+    }
+}

EnvelopeGenerator.Application/Contracts/ICodeGenerator.cs

@@ -0,0 +1,7 @@
+namespace EnvelopeGenerator.Application.Contracts
+{
+    public interface ICodeGenerator
+    {
+        string GenerateCode(int length);
+    }
+}

EnvelopeGenerator.Application/DIExtensions.cs

@@ -15,7 +15,7 @@ namespace EnvelopeGenerator.Application
 {
     public static class DIExtensions
     {
-        public static IServiceCollection AddEnvelopeGenerator(this IServiceCollection services, IConfigurationSection dispatcherConfigSection, IConfigurationSection mailConfigSection, IConfigurationSection smsConfigSection)
+        public static IServiceCollection AddEnvelopeGenerator(this IServiceCollection services, IConfigurationSection dispatcherConfigSection, IConfigurationSection mailConfigSection, IConfigurationSection smsConfigSection, IConfigurationSection codeGeneratorConfigSection)
         {
             //Inject CRUD Service and repositoriesad
             services.TryAddScoped<IConfigRepository, ConfigRepository>();
@@ -48,6 +48,7 @@ namespace EnvelopeGenerator.Application
             services.TryAddScoped<IReceiverService, ReceiverService>();
             services.TryAddScoped<IUserReceiverService, UserReceiverService>();
             services.TryAddScoped<IEnvelopeReceiverReadOnlyService, EnvelopeReceiverReadOnlyService>();
+            services.TryAddScoped<ICodeGenerator, CodeGenerator>();
 
             //Auto mapping profiles
             services.AddAutoMapper(typeof(BasicDtoMappingProfile).Assembly);
@@ -55,6 +56,7 @@ namespace EnvelopeGenerator.Application
 
             services.Configure<DispatcherConfig>(dispatcherConfigSection);
             services.Configure<MailConfig>(mailConfigSection);
+            services.Configure<CodeGeneratorConfig>(codeGeneratorConfigSection);
 
             services.AddHttpClientService<SmsParams>(smsConfigSection);
             services.TryAddSingleton<IMessagingService, GtxMessagingService>();
@@ -65,6 +67,7 @@ namespace EnvelopeGenerator.Application
         public static IServiceCollection AddEnvelopeGenerator(this IServiceCollection services, IConfiguration config) => services.AddEnvelopeGenerator(
             dispatcherConfigSection: config.GetSection("DispatcherConfig"),
             mailConfigSection: config.GetSection("MailConfig"),
-            smsConfigSection: config.GetSection("SmsConfig"));
+            smsConfigSection: config.GetSection("SmsConfig"),
+            codeGeneratorConfigSection: config.GetSection("CodeGeneratorConfig"));
     }
 }

EnvelopeGenerator.Application/Services/CodeGenerator.cs

@@ -0,0 +1,37 @@
+using EnvelopeGenerator.Application.Configurations;
+using EnvelopeGenerator.Application.Contracts;
+using Microsoft.Extensions.Options;
+using System.Text;
+
+namespace EnvelopeGenerator.Application.Services
+{
+    public class CodeGenerator : ICodeGenerator
+    {
+        public static Lazy<CodeGenerator> LazyStatic => new(() => new CodeGenerator(Options.Create<CodeGeneratorConfig>(new())));
+
+        public static CodeGenerator Static => LazyStatic.Value;
+
+        private readonly string _charPool = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
+
+        public CodeGenerator(IOptions<CodeGeneratorConfig> options)
+        {
+            _charPool = options.Value.CharPool;
+        }
+
+        public string GenerateCode(int length)
+        {
+            //TODO: Inject Random as a singleton to support multithreading to improve performance.
+            Random random = new();
+
+            if (length <= 0)
+                throw new ArgumentException("Password length must be greater than 0.");
+
+            var passwordBuilder = new StringBuilder(length);
+
+            for (int i = 0; i < length; i++)
+                passwordBuilder.Append(_charPool[random.Next(_charPool.Length)]);
+
+            return passwordBuilder.ToString();
+        }
+    }
+}

EnvelopeGenerator.Web/Controllers/HomeController.cs

@@ -192,6 +192,7 @@ namespace EnvelopeGenerator.Web.Controllers
                                 return View("EnvelopeLocked").WithData("ViaSms", true);
                             }
 
+                            //continue the process without important data to minimize security errors.
                             var er = er_secret.WithoutSecrets;
 
 							ViewData["EnvelopeKey"] = envelopeReceiverId;