# name: discourse-assign
# about: Assign users to topics
# version: 0.1
# authors: Sam Saffron

register_asset 'stylesheets/assigns.scss'

after_initialize do

  module ::DiscourseAssign
    class Engine < ::Rails::Engine
      engine_name "discourse_assign"
      isolate_namespace DiscourseAssign
    end
  end

  class ::DiscourseAssign::AssignController < Admin::AdminController
    before_filter :ensure_logged_in

    def unassign
      topic_id = params.require(:topic_id)
      topic = Topic.find(topic_id.to_i)
      if assigned_to_id = topic.custom_fields["assigned_to_id"]
        topic.custom_fields["assigned_to_id"] = nil
        topic.custom_fields["assigned_by_id"] = nil
        topic.save!

        post = topic.posts.where(post_number: 1).first
        post.publish_change_to_clients!(:revised, { reload_topic: true })

        assigned_user = User.find_by(id: assigned_to_id)

        UserAction.where(
          action_type: UserAction::ASSIGNED,
          target_post_id: post.id
        ).destroy_all

        # yank notification
        Notification.where(
           notification_type: Notification.types[:custom],
           user_id: assigned_user.try(:id),
           topic_id: topic.id,
           post_number: 1
        ).where("data like '%discourse_assign.assign_notification%'")
         .destroy_all


        post_type = SiteSetting.assigns_public ? Post.types[:small_action] : Post.types[:whisper]
        topic.add_moderator_post(current_user,
                                 I18n.t('discourse_assign.unassigned'),
                                 { bump: false,
                                   post_type: post_type,
                                   action_code: "assigned"})
      end

      render json: success_json
    end

    def assign
      topic_id = params.require(:topic_id)
      username = params.require(:username)

      topic = Topic.find(topic_id.to_i)
      assign_to = User.find_by(username_lower: username.downcase)

      raise Discourse::NotFound unless assign_to

      #Scheduler::Defer.later "assign topic" do

        topic.custom_fields["assigned_to_id"] = assign_to.id
        topic.custom_fields["assigned_by_id"] = current_user.id
        topic.save!

        topic.posts.first.publish_change_to_clients!(:revised, { reload_topic: true })


        UserAction.log_action!(action_type: UserAction::ASSIGNED,
                              user_id: assign_to.id,
                              acting_user_id: current_user.id,
                              target_post_id: topic.posts.find_by(post_number: 1).id,
                              target_topic_id: topic.id)

        post_type = SiteSetting.assigns_public ? Post.types[:small_action] : Post.types[:whisper]

        topic.add_moderator_post(current_user,
                                 I18n.t('discourse_assign.assigned_to',
                                         username: assign_to.username),
                                 { bump: false,
                                   post_type: post_type,
                                   action_code: "assigned"})

        unless current_user.id == assign_to.id

          Notification.create!(notification_type: Notification.types[:custom],
                             user_id: assign_to.id,
                             topic_id: topic.id,
                             post_number: 1,
                             data: {
                               message: 'discourse_assign.assign_notification',
                               display_username: current_user.username,
                               topic_title: topic.title
                             }.to_json
                            )
        end


      render json: success_json
    end

    class ::Topic
      def assigned_to_user
        @assigned_to_user ||
          if user_id = custom_fields["assigned_to_id"]
            @assigned_to_user = User.find_by(id: user_id)
          end
      end

      def preload_assigned_to_user(assigned_to_user)
        @assigned_to_user = assigned_to_user
      end
    end

    TopicList.preloaded_custom_fields << "assigned_to_id"

    TopicList.on_preload do |topics, topic_list|
      is_staff = topic_list.current_user && topic_list.current_user.staff?
      allowed_access = SiteSetting.assigns_public || is_staff

      if allowed_access && topics.length > 0
        users = User.where("id in (
              SELECT value::int
              FROM topic_custom_fields
              WHERE name = 'assigned_to_id' AND topic_id IN (?)
        )", topics.map(&:id))
        .select(:id, :email, :username, :uploaded_avatar_id)

        map = {}
        users.each{|u| map[u.id] = u}

        topics.each do |t|
          if id = t.custom_fields['assigned_to_id']
            t.preload_assigned_to_user(map[id.to_i])
          end
        end
      end
    end

    require_dependency 'topic_query'
    TopicQuery.add_custom_filter(:assigned) do |results, topic_query|
      if topic_query.guardian.is_staff? || SiteSetting.assigns_public
        username = topic_query.options[:assigned]
        user_id = User.where(username_lower: username.downcase).pluck(:id).first if username.present? && username != "*"
        if user_id || username == "*"

          if username == "*"
            filter = "AND tc_assign.value IS NOT NULL"
          else
            filter = "AND tc_assign.value = '#{user_id.to_i.to_s}'"
          end

          results = results.joins("JOIN topic_custom_fields tc_assign ON
                                    topics.id = tc_assign.topic_id AND
                                    tc_assign.name = 'assigned_to_id'
                                    #{filter}
                                  ")
        end
      end

      results
    end

    require_dependency 'listable_topic_serializer'
    class ::ListableTopicSerializer
      has_one :assigned_to_user, serializer: BasicUserSerializer, embed: :objects

      def include_assigned_to_user?
        (SiteSetting.assigns_public || scope.is_staff?) && object.assigned_to_user
      end
    end

    require_dependency 'topic_view_serializer'
    class ::TopicViewSerializer
      attributes :assigned_to_user

      def assigned_to_user
        if user = User.find_by(id: assigned_to_user_id)

          assigned_at = TopicCustomField.where(
            topic_id: object.topic.id,
            name: "assigned_to_id"
          ).pluck(:created_at).first

          {
            username: user.username,
            name: user.name,
            avatar_template: user.avatar_template,
            assigned_at: assigned_at
          }
        end
      end

      def include_assigned_to_user?
        if SiteSetting.assigns_public ||  scope.is_staff?
          assigned_to_user_id
        end
      end

      def assigned_to_user_id
        id = object.topic.custom_fields["assigned_to_id"]
        # a bit messy but race conditions can give us an array here, avoid
        id && id.to_i rescue nil
      end
    end

    DiscourseAssign::Engine.routes.draw do
      put "/assign" => "assign#assign"
      put "/unassign" => "assign#unassign"
    end

    Discourse::Application.routes.append do
      mount ::DiscourseAssign::Engine, at: "/assign"
    end

  end
end