feat(ReceiverAlreadySignedQuery): create with handler

EnvelopeGenerator.Application/EnvelopeReceivers/Queries/ReadEnvelopeReceiverQuery.cs

@@ -85,11 +85,20 @@ public record ReadEnvelopeReceiverQuery : IRequest<IEnumerable<EnvelopeReceiverD
     public ReadReceiverQuery? Receiver { get; set; }
 };
 
+/// <summary>
+/// 
+/// </summary>
 public static class Extensions
 {
-    public static Task<EnvelopeReceiverDto?> ReadEnvelopeReceiverAsync(this IMediator mediator, string key)
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="mediator"></param>
+    /// <param name="key"></param>
+    /// <returns></returns>
+    public static Task<EnvelopeReceiverDto?> ReadEnvelopeReceiverAsync(this IMediator mediator, string key, CancellationToken cancel = default)
     {
         var q = new ReadEnvelopeReceiverQuery() { Key = key };
-        return mediator.Send(q).Then(envRcvs => envRcvs.FirstOrDefault());
+        return mediator.Send(q, cancel).Then(envRcvs => envRcvs.FirstOrDefault());
     }
 }

EnvelopeGenerator.Application/EnvelopeReceivers/Queries/ReceiverAlreadySignedQuery.cs

@@ -0,0 +1,82 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Application.Exceptions;
+using EnvelopeGenerator.Domain;
+using EnvelopeGenerator.Domain.Entities;
+using EnvelopeGenerator.Extensions;
+using MediatR;
+using Microsoft.EntityFrameworkCore;
+
+namespace EnvelopeGenerator.Application.EnvelopeReceivers.Queries;
+
+/// <summary>
+/// 
+/// </summary>
+public record ReceiverAlreadySignedQuery : IRequest<bool>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public required string Key
+    {
+        get => (EnvelopeUuid, ReceiverSignature).EncodeEnvelopeReceiverId();
+        init
+        {
+            (string? EnvelopeUuid, string? ReceiverSignature) = value.DecodeEnvelopeReceiverId();
+            if (string.IsNullOrEmpty(EnvelopeUuid) || string.IsNullOrEmpty(ReceiverSignature))
+            {
+                throw new BadRequestException("Der EnvelopeReceiverKey muss ein gültiger Base64-kodierter String sein, der die EnvelopeUuid und die ReceiverSignature enthält.");
+            }
+        }
+    }
+
+    internal string EnvelopeUuid { get; set; } = null!;
+
+    internal string ReceiverSignature { get; set; } = null!;
+}
+
+/// <summary>
+/// 
+/// </summary>
+public static class ReceiverAlreadySignedQueryExtensions
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="mediator"></param>
+    /// <param name="key"></param>
+    /// <returns></returns>
+    public static Task<bool> ReceiverAlreadySigned(IMediator mediator, string key)
+        => mediator.Send(new ReceiverAlreadySignedQuery { Key = key });
+}
+
+/// <summary>
+/// 
+/// </summary>
+public class ReceiverAlreadySignedQueryHandler : IRequestHandler<ReceiverAlreadySignedQuery, bool>
+{
+    private readonly IRepository<EnvelopeReceiver> _repo;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="repo"></param>
+    public ReceiverAlreadySignedQueryHandler(IRepository<EnvelopeReceiver> repo)
+    {
+        _repo = repo;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="request"></param>
+    /// <param name="cancel"></param>
+    /// <returns></returns>
+    public async Task<bool> Handle(ReceiverAlreadySignedQuery request, CancellationToken cancel = default)
+    {
+        return await _repo.Read()
+            .Where(er => er.Envelope.Uuid == request.EnvelopeUuid)
+            .Where(er => er.Receiver.Signature == request.ReceiverSignature)
+            .Where(er => er.Envelope.History.Any(hist => hist.Status == Constants.EnvelopeStatus.DocumentSigned))
+            .AnyAsync(cancel);
+    }
+}