add filter validation

modules/claims_api/app/controllers/claims_api/v2/veterans/power_of_attorney/request_controller.rb

@@ -15,6 +15,7 @@ def index
           poa_codes = form_attributes['poaCodes']
           page_size = form_attributes['pageSize']
           page_index = form_attributes['pageIndex']
+          filter = form_attributes['filter']
 
           unless poa_codes.is_a?(Array) && poa_codes.size.positive?
             raise ::Common::Exceptions::ParameterMissing.new('poaCodes',
@@ -26,6 +27,8 @@ def index
                                                              detail: 'pageSize is required when pageIndex is present')
           end
 
+          validate_filter!(filter)
+
           service = ManageRepresentativeService.new(external_uid: 'power_of_attorney_request_uid',
                                                     external_key: 'power_of_attorney_request_key')
 
@@ -130,6 +133,40 @@ def build_bgs_attributes(form_attributes)
           bgs_form_attributes
         end
 
+        def validate_filter!(filter)
+          return nil if filter.blank?
+
+          valid_filters = %w[status state city country sensitivityLevel]
+
+          invalid_filters = filter.keys - valid_filters
+
+          if invalid_filters.any?
+            raise ::Common::Exceptions::UnprocessableEntity.new(
+              detail: "Invalid filter(s): #{invalid_filters.join(', ')}"
+            )
+          end
+
+          validate_statuses!(filter['status'])
+        end
+
+        def validate_statuses!(statuses)
+          return nil if statuses.blank?
+
+          unless statuses.is_a?(Array)
+            raise ::Common::Exceptions::UnprocessableEntity.new(
+              detail: 'filter status must be an array'
+            )
+          end
+
+          valid_statuses = %w[new accepted declined]
+
+          if statuses.any? { |status| valid_statuses.exclude?(status.downcase) }
+            raise ::Common::Exceptions::UnprocessableEntity.new(
+              detail: "Status(es) must be one of: #{valid_statuses.join(', ')}"
+            )
+          end
+        end
+
         def normalize(item)
           item.to_s.strip.downcase
         end