[E] Add by_subject scope to journal

* Also allow filtering subjects to used by journals

Author: 1aurend

api/app/controllers/concerns/validation.rb

@@ -607,7 +607,7 @@ def annotation_filter_params
   end
 
   def subject_filter_params
-    params.permit(filter: [:featured, :keyword, :typeahead, :used])[:filter] || {}
+    params.permit(filter: [:featured, :keyword, :typeahead, :used, :used_journal])[:filter] || {}
   end
 
   def collaborator_filter_params
@@ -635,7 +635,7 @@ def journal_issue_filter_params
 
   def journal_filter_params
     params.permit(
-      filter: [:draft, :keyword, :order, :typeahead, :show_on_homepage, :with_update_ability, :with_update_or_issue_update_ability]
+      filter: [:draft, :keyword, :order, :typeahead, :show_on_homepage, :with_update_ability, :with_update_or_issue_update_ability, :subject]
     )[:filter]
   end
 

api/app/models/journal.rb

@@ -87,6 +87,13 @@ class Journal < ApplicationRecord
   scope :with_update_ability, ->(user = nil) { build_update_ability_scope_for user }
   scope :with_update_or_issue_update_ability, ->(user = nil) { build_update_or_issue_update_ability_for user }
 
+  scope :by_subject, ->(subject = nil) {
+    next all unless subject.present?
+
+    where(id: unscoped.joins(:journal_subjects)
+                      .merge(JournalSubject.by_subject(subject)).select(:journal_id))
+  }
+
   multisearches! :description_plaintext
 
   has_keyword_search!(

api/app/models/subject.rb

@@ -33,6 +33,12 @@ class Subject < ApplicationRecord
     joins(:project_subjects).where.not(project_subjects: { id: nil }).group(:id)
   }
 
+  scope :by_used_journal, ->(used = nil) {
+    return all unless used.present?
+
+    joins(:journal_subjects).where.not(journal_subjects: { id: nil }).group(:id)
+  }
+
   validates :name, presence: true, uniqueness: true
 
   alias_attribute :title, :name