DEV: Move discourse-assign to core (#33570)

https://meta.discourse.org/t/373574

Internal `/t/-/156778`

plugins/discourse-assign/lib/pending_assigns_reminder.rb

@@ -0,0 +1,142 @@
+# frozen_string_literal: true
+
+class PendingAssignsReminder
+  REMINDED_AT = "last_reminded_at"
+  REMINDERS_FREQUENCY = "remind_assigns_frequency"
+  CUSTOM_FIELD_NAME = "assigns_reminder"
+
+  def remind(user)
+    newest_topics = assigned_topics(user, order: :desc)
+    return if newest_topics.size < SiteSetting.pending_assign_reminder_threshold
+
+    delete_previous_reminders(user)
+
+    oldest_topics = assigned_topics(user, order: :asc).where.not(id: newest_topics.map(&:id))
+    assigned_topics_count = assigned_count_for(user)
+    title = I18n.t("pending_assigns_reminder.title", pending_assignments: assigned_topics_count)
+
+    PostCreator.create!(
+      Discourse.system_user,
+      title: title,
+      raw: reminder_body(user, assigned_topics_count, newest_topics, oldest_topics),
+      archetype: Archetype.private_message,
+      subtype: TopicSubtype.system_message,
+      target_usernames: user.username,
+      custom_fields: {
+        CUSTOM_FIELD_NAME => true,
+      },
+    )
+
+    update_last_reminded(user)
+  end
+
+  private
+
+  def delete_previous_reminders(user)
+    posts =
+      Post
+        .joins(topic: { topic_allowed_users: :user })
+        .where(
+          topic: {
+            posts_count: 1,
+            user_id: Discourse.system_user,
+            archetype: Archetype.private_message,
+            subtype: TopicSubtype.system_message,
+            topic_allowed_users: {
+              users: {
+                id: user.id,
+              },
+            },
+          },
+        )
+        .joins(topic: :_custom_fields)
+        .where(topic_custom_fields: { name: CUSTOM_FIELD_NAME })
+
+    posts.find_each { |post| PostDestroyer.new(Discourse.system_user, post).destroy }
+  end
+
+  def visible_topics(user)
+    Topic.listable_topics.secured(Guardian.new(user)).or(Topic.private_messages_for_user(user))
+  end
+
+  def assigned_count_for(user)
+    assignments =
+      Assignment
+        .joins_with_topics
+        .where(assigned_to_id: user.id, assigned_to_type: "User", active: true)
+        .merge(visible_topics(user))
+    assignments =
+      DiscoursePluginRegistry.apply_modifier(:assigned_count_for_user_query, assignments, user)
+    assignments.count
+  end
+
+  def assigned_topics(user, order:)
+    secure = visible_topics(user)
+
+    topics =
+      Topic
+        .joins(:assignment)
+        .select(:slug, :id, :title, :fancy_title, "assignments.created_at AS assigned_at")
+        .where(
+          "assignments.assigned_to_id = ? AND assignments.assigned_to_type = 'User' AND assignments.active",
+          user.id,
+        )
+    topics = DiscoursePluginRegistry.apply_modifier(:assigns_reminder_assigned_topics_query, topics)
+    topics.merge(secure).order("assignments.created_at #{order}").limit(3)
+  end
+
+  def reminder_body(user, assigned_topics_count, first_three_topics, last_three_topics)
+    newest_list = build_list_for(:newest, first_three_topics)
+    oldest_list = build_list_for(:oldest, last_three_topics)
+
+    I18n.t(
+      "pending_assigns_reminder.body",
+      pending_assignments: assigned_topics_count,
+      assignments_link: "#{Discourse.base_url}/u/#{user.username_lower}/activity/assigned",
+      newest_assignments: newest_list,
+      oldest_assignments: oldest_list,
+      frequency: frequency_in_words(user),
+    )
+  end
+
+  def build_list_for(key, topics)
+    return "" if topics.empty?
+    initial_list = { "topic_0" => "", "topic_1" => "", "topic_2" => "" }
+    items =
+      topics
+        .each_with_index
+        .reduce(initial_list) do |memo, (t, index)|
+          memo[
+            "topic_#{index}"
+          ] = "- [#{Emoji.gsub_emoji_to_unicode(t.fancy_title)}](#{t.relative_url}) - assigned #{time_in_words_for(t)}"
+          memo
+        end
+
+    I18n.t("pending_assigns_reminder.#{key}", items.symbolize_keys!)
+  end
+
+  def time_in_words_for(topic)
+    AgeWords.distance_of_time_in_words(
+      Time.zone.now,
+      topic.assigned_at.to_time,
+      false,
+      scope: "datetime.distance_in_words_verbose",
+    )
+  end
+
+  def frequency_in_words(user)
+    frequency =
+      if user.custom_fields&.has_key?(REMINDERS_FREQUENCY)
+        user.custom_fields[REMINDERS_FREQUENCY]
+      else
+        SiteSetting.remind_assigns_frequency
+      end
+
+    ::RemindAssignsFrequencySiteSettings.frequency_for(frequency)
+  end
+
+  def update_last_reminded(user)
+    update_last_reminded = { REMINDED_AT => DateTime.now }
+    user.upsert_custom_fields(update_last_reminded)
+  end
+end