refactor(SaveDocStatusCommand): simplify repository filtering in SaveDocStatusCommandHandler

- Replaced explicit envelope and receiver expression filters with a single `.Where(request)` call.
- Removed redundant checks for null and empty values in handler.
- Updated using statements to include `EnvelopeGenerator.Application.Extensions`.
- Maintains the same functionality while reducing code complexity.

EnvelopeGenerator.Application/DocStatus/Commands/SaveDocStatusCommand.cs

@@ -1,9 +1,8 @@
 using DigitalData.Core.Abstraction.Application.Repository;
-using DigitalData.Core.Exceptions;
 using EnvelopeGenerator.Domain.Entities;
 using MediatR;
 using Microsoft.EntityFrameworkCore;
-using System.Linq.Expressions;
+using EnvelopeGenerator.Application.Extensions;
 
 namespace EnvelopeGenerator.Application.DocStatus.Commands;
 
@@ -60,30 +59,13 @@ public class SaveDocStatusCommandHandler : IRequestHandler<SaveDocStatusCommand,
     /// <returns></returns>
     public async Task<int?> Handle(SaveDocStatusCommand request, CancellationToken cancel)
     {
-        // envelope filter
-        Expression<Func<DocumentStatus, bool>>? eExp =
-            request.Envelope.Id is not null 
-            ? ds => ds.EnvelopeId == request.Envelope.Id
-                : !string.IsNullOrWhiteSpace(request.Envelope.Uuid) 
-                ? ds => ds.Envelope.Uuid == request.Envelope.Uuid
-                    : throw new BadRequestException();
-
-        // receiver filter
-        Expression<Func<DocumentStatus, bool>>? rExp =
-            request.Receiver.Id is not null
-                ? ds => ds.ReceiverId == request.Receiver.Id
-                : request.Receiver.EmailAddress is not null
-                    ? ds => ds.Receiver.EmailAddress == request.Receiver.EmailAddress
-                    : !string.IsNullOrWhiteSpace(request.Receiver.Signature) ? ds => ds.Receiver.Signature == request.Receiver.Signature
-                        : throw new BadRequestException();
-
         // ceck if exists
-        bool isExists = await _repo.ReadOnly().Where(eExp).Where(rExp).AnyAsync(cancel);
+        bool isExists = await _repo.ReadOnly().Where(request).AnyAsync(cancel);
 
         if (isExists)
         {
             var uReq = request.To<UpdateDocStatusCommand>();
-            await _repo.UpdateAsync(uReq, q => q.Where(eExp).Where(rExp), cancel);
+            await _repo.UpdateAsync(uReq, q => q.Where(request), cancel);
         }
         else
         {
@@ -91,7 +73,7 @@ public class SaveDocStatusCommandHandler : IRequestHandler<SaveDocStatusCommand,
             await _repo.CreateAsync(cReq, cancel);
         }
 
-        var docStatus = await _repo.ReadOnly().Where(eExp).Where(rExp).SingleOrDefaultAsync(cancel);
+        var docStatus = await _repo.ReadOnly().Where(request).SingleOrDefaultAsync(cancel);
         return docStatus?.Id;
     }
 }