trustieforge/app/api/mobile/entities/news.rb

module Mobile
  module Entities
    class News < Grape::Entity
      include Redmine::I18n
      include ApiHelper
      def self.news_expose(field)
        expose field do |f,opt|
          if f.is_a?(Hash) && f.key?(field)
            f[field]
          elsif f.is_a?(::News)
            if f.respond_to?(field)
              if field == :created_on
                format_time(f.send(field))
              else
                f.send(field)
              end
            else
              case field
                when :course_name
                  get_course(f.course_id).name unless f.course_id == nil
                when :praise_count
                  get_activity_praise_num(f)
                when :act_type
                  'News'
                when :act_id
                  f.id
                when :comment_count
                  f.comments.count
              end
            end
          elsif f.is_a?(::Comment)
            case field
              when :content
                f[:comments]
              when :lasted_comment
                time_from_now f.created_on
              when :act_id
                f.id
              when :praise_count
                get_activity_praise_num(f)
              when :act_type
                'Comment'
            end

          elsif f.is_a?(Hash) && !f.key?(field)
            n = f[:news]
            comments = f[:comments]
            if n.is_a?(::News)
              if field == :created_on
                format_time(n.send(field)) if n.respond_to?(field)
              else
                n.send(field) if n.respond_to?(field)
              end

            end

          end
        end
      end
      expose :id
      #新闻标题
      news_expose :title

      expose :user,using: Mobile::Entities::User do |f, opt|
        obj = nil
        if f.is_a?(::News) && f.respond_to?(:author)
          obj = f.send(:author)
        elsif f.is_a?(::Comment) && f.respond_to?(:author)
          obj = f.send(:author)
        elsif f.is_a?(Hash) && f.key?(:author)
          obj = f[:author]
        end
        obj
      end
      news_expose :act_type
      news_expose :act_id
      #作者id
      news_expose :author_id
      #作者名
      news_expose :author_name
      #作者头像url
      news_expose :author_img_url
      #新闻内容
      news_expose :description
      #发布时间
      news_expose :created_on
      #评论数量
      news_expose :comment_count
      news_expose :praise_count
      #课程名字
      news_expose :course_name
      news_expose :lasted_comment

      #评论
      # expose :comments, using: Mobile::Entities::Comment do |f, opt|
      #   if f.is_a?(Hash) && f.key?(:comments)
      #     f[:comments]
      #   elsif f.is_a?(::News) && f.respond_to?(:comments)
      #     f.comments.reverse
      #   end
      # end

      news_expose :content

      expose :all_children, using: Mobile::Entities::News  do |f, opt|
        #f[:journals_for_messages] if f.is_a?(Hash) && f.key?(:journals_for_messages)
        if f.is_a?(::News)
          # f.journals_for_messages.reverse
          if !opt[:children] && opt[:type] == 0
            opt[:children] = true
            tStart = opt[:page]*5
            tEnd = (opt[:page]+1)*5 - 1

            all_comments = f.comments.reorder("created_on desc")
            all_comments[tStart..tEnd]
          end
        end
      end

      expose :has_praise , if: lambda { |instance, options| options[:user] } do |instance, options|
        has_praise = false
        current_user = options[:user]
        obj = PraiseTread.where("praise_tread_object_id=? and praise_tread_object_type=? and user_id=?",instance.id,instance.class.to_s,current_user.id)
        has_praise = obj.empty? ? false : true
        has_praise
      end

      expose :parents_count, if: lambda { |instance, options| options[:user] } do |instance, options|
        if instance.is_a?(::Comment)
          parents_reply = []
          parents_reply = get_reply_parents(parents_reply, instance)
          parents_reply.count
        end
      end

      expose :parents_reply_bottom, using:Mobile::Entities::News do |f,opt|
        if f.is_a? (::Comment)
          #取二级回复的底楼层
          parents_reply = []
          parents_reply = get_reply_parents(parents_reply, f)
          if parents_reply.count > 0 && !opt[:bottom]
            if opt[:type] == 1
              # opt[:bottom] = true
              # parents_reply[opt[:page]..opt[:page]]
            else
              opt[:bottom] = true
              parents_reply[0..0]
            end
          else
            []
          end
        end
      end

      expose :parents_reply_top, using:Mobile::Entities::News do |f,opt|
        if f.is_a? (::Comment)
          #取二级回复的顶楼层
          parents_reply = []
          parents_reply = get_reply_parents(parents_reply, f)
          if parents_reply.count > 2 && !opt[:top]
            if opt[:type] == 1
              opt[:top] = true
              tStart = (opt[:page]-1)*5+2
              tEnd = (opt[:page])*5+2 - 1

              if tEnd >= parents_reply.count - 1
                tEnd = parents_reply.count - 2
              end

              if tStart <= parents_reply.count - 2
                parents_reply = parents_reply.reverse[tStart..tEnd]
                parents_reply.reverse
              else
                []
              end
            else
              opt[:top] = true
              parents_reply = parents_reply.reverse[0..1]
              parents_reply.reverse
            end
          elsif parents_reply.count == 2 && !opt[:top]
            opt[:top] = true
            parents_reply = parents_reply.reverse[0..0]
            parents_reply.reverse
          else
            []
          end
        end
      end
    end
  end
end