FEATURE: solved topic auto close setting per category

assets/javascripts/discourse/connectors/category-custom-settings/solved-settings.hbs

@@ -1,5 +1,6 @@
+<h3>{{i18n "solved.title"}}</h3>
+
 {{#unless siteSettings.allow_solved_on_all_topics}}
-  <h3>{{i18n "solved.title"}}</h3>
   <section class="field">
     <div class="enable-accepted-answer">
       <label class="checkbox-label">
@@ -12,4 +13,16 @@
       </label>
     </div>
   </section>
-{{/unless}}
+{{/unless}}
+
+<section class="field auto-close-solved-topics">
+  <label for="auto-close-solved-topics">
+    {{i18n "solved.solved_topics_auto_close_hours"}}
+  </label>
+  <NumberField
+    @number={{this.category.custom_fields.solved_topics_auto_close_hours}}
+    @id="auto-close-solved-topics"
+    @type="number"
+    @min="0"
+  />
+</section>

config/locales/client.en.yml

@@ -9,6 +9,7 @@ en:
     solved:
       title: "Solved"
       allow_accepted_answers: "Allow topic owner and staff to mark a reply as the solution"
+      solved_topics_auto_close_hours: "Auto close topic (n) hours after the last reply once the topic has been marked as solved."
       accept_answer: "Select if this reply solves the problem"
       accepted_description: "This is the accepted solution to this topic"
       has_no_accepted_answer: "This topic has no solution"

plugin.rb

@@ -133,7 +133,15 @@ def self.accept_answer!(post, acting_user, topic: nil)
           )
         end
 
-        auto_close_hours = SiteSetting.solved_topics_auto_close_hours
+        if topic&.category.present?
+          auto_close_hours =
+            topic&.category&.custom_fields&.[]("solved_topics_auto_close_hours").to_i
+          auto_close_hours = 175_200 if auto_close_hours > 175_200 # 20 years
+        end
+
+        if auto_close_hours.nil? || auto_close_hours == 0
+          auto_close_hours = SiteSetting.solved_topics_auto_close_hours
+        end
 
         if (auto_close_hours > 0) && !topic.closed
           topic_timer =

spec/integration/solved_spec.rb

@@ -61,6 +61,32 @@
       expect(topic.public_topic_timer.based_on_last_post).to eq(true)
     end
 
+    it "gives priority to category's solved_topics_auto_close_hours setting" do
+      freeze_time
+      custom_auto_close_category = Fabricate(:category)
+      topic_2 = Fabricate(:topic, category: custom_auto_close_category)
+      post_2 = Fabricate(:post, topic: topic_2)
+      custom_auto_close_category.custom_fields["solved_topics_auto_close_hours"] = 4
+      custom_auto_close_category.save_custom_fields
+
+      post "/solution/accept.json", params: { id: post_2.id }
+
+      expect(response.status).to eq(200)
+      expect(post_2.reload.custom_fields["is_accepted_answer"]).to eq("true")
+
+      topic_2.reload
+
+      expect(topic_2.public_topic_timer.status_type).to eq(TopicTimer.types[:silent_close])
+
+      expect(
+        topic_2.custom_fields[DiscourseSolved::AUTO_CLOSE_TOPIC_TIMER_CUSTOM_FIELD].to_i,
+      ).to eq(topic_2.public_topic_timer.id)
+
+      expect(topic_2.public_topic_timer.execute_at).to eq_time(Time.zone.now + 4.hours)
+
+      expect(topic_2.public_topic_timer.based_on_last_post).to eq(true)
+    end
+
     it "sends notifications to correct users" do
       SiteSetting.notify_on_staff_accept_solved = true
       user = Fabricate(:user)