New: Custom Format Spec Validation

Fixes #7405

src/NzbDrone.Core/CustomFormats/Specifications/ResolutionSpecification.cs

@@ -1,11 +1,23 @@
+using FluentValidation;
 using NzbDrone.Core.Annotations;
 using NzbDrone.Core.Parser;
 using NzbDrone.Core.Parser.Model;
+using NzbDrone.Core.Validation;
 
 namespace NzbDrone.Core.CustomFormats
 {
+    public class ResolutionSpecificationValidator : AbstractValidator<ResolutionSpecification>
+    {
+        public ResolutionSpecificationValidator()
+        {
+            RuleFor(c => c.Value).NotEmpty();
+        }
+    }
+
     public class ResolutionSpecification : CustomFormatSpecificationBase
     {
+        private static readonly ResolutionSpecificationValidator Validator = new ResolutionSpecificationValidator();
+
         public override int Order => 6;
         public override string ImplementationName => "Resolution";
 
@@ -16,5 +28,10 @@ namespace NzbDrone.Core.CustomFormats
         {
             return (movieInfo?.Quality?.Quality?.Resolution ?? (int)Resolution.Unknown) == Value;
         }
+
+        public override NzbDroneValidationResult Validate()
+        {
+            return new NzbDroneValidationResult(Validator.Validate(this));
+        }
     }
 }