FEATURE: adds a currently away report (#234)

config/locales/server.en.yml

@@ -45,6 +45,10 @@ en:
     more_than_one_calendar: "You can’t have more than one calendar in a post."
     more_than_two_dates: "A post of a calendar topic can’t contain more than two dates."
     event_expired: "Event expired"
+  reports:
+    currently_away:
+      labels:
+        username: Username
   discourse_post_event:
     notifications:
       before_event_reminder: "%{title} is about to start."

plugin.rb

@@ -657,4 +657,23 @@ after_initialize do
 
   register_notification_consolidation_plan(reminders_consolidation_plan)
   register_notification_consolidation_plan(invitation_consolidation_plan)
+
+  Report.add_report('currently_away') do |report|
+    group_filter = report.filters.dig(:group) || Group::AUTO_GROUPS[:staff]
+    report.add_filter('group', type: 'group', default: group_filter)
+
+    return unless group = Group.find_by(id: group_filter)
+
+    report.labels = [
+      {
+        property: :username,
+        title: I18n.t('reports.currently_away.labels.username')
+      },
+    ]
+
+    group_usernames = group.users.pluck(:username)
+    on_holiday_usernames = DiscourseCalendar.users_on_holiday
+    report.data = (group_usernames & on_holiday_usernames).map { |username| { username: username } }
+    report.total = report.data.count
+  end
 end

spec/acceptance/curently_away_report_spec.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+describe 'currently_away report' do
+  fab!(:user_1) { Fabricate(:user) }
+  fab!(:user_2) { Fabricate(:user) }
+  fab!(:group_1) { Fabricate(:group) }
+
+  before do
+    group_1.add(user_1)
+
+    DiscourseCalendar.users_on_holiday = [user_1.username]
+  end
+
+  it 'generates a correct report' do
+    report = Report.find('currently_away', filters: { group: group_1.id })
+
+    expect(report.data).to contain_exactly({ username: user_1.username })
+    expect(report.total).to eq(1)
+  end
+end