require 'csv'
require_dependency 'system_message'

module Jobs

  class ExportCsvFile < Jobs::Base
    include ActionView::Helpers::NumberHelper

    sidekiq_options retry: false

    HEADER_ATTRS_FOR ||= HashWithIndifferentAccess.new({
      user_archive:   ['topic_title','category','sub_category','is_pm','post','like_count','reply_count','url','created_at'],
      user_list:      ['id','name','username','email','title','created_at','last_seen_at','last_posted_at','last_emailed_at','trust_level','approved','suspended_at','suspended_till','blocked','active','admin','moderator','ip_address'],
      user_stats:     ['topics_entered','posts_read_count','time_read','topic_count','post_count','likes_given','likes_received'],
      user_sso:       ['external_id','external_email', 'external_username', 'external_name', 'external_avatar_url'],
      staff_action:   ['staff_user','action','subject','created_at','details', 'context'],
      screened_email: ['email','action','match_count','last_match_at','created_at','ip_address'],
      screened_ip:    ['ip_address','action','match_count','last_match_at','created_at'],
      screened_url:   ['domain','action','match_count','last_match_at','created_at'],
      report:         ['date', 'value'],
    })

    def execute(args)
      @entity = args[:entity]
      @extra = HashWithIndifferentAccess.new(args[:args]) if args[:args]
      @current_user = User.find_by(id: args[:user_id])

      export_method = :"#{@entity}_export"
      raise Discourse::InvalidParameters.new(:entity) unless respond_to?(export_method)

      file_name_prefix = if @entity == "user_archive"
        "#{@entity.split('_').join('-')}-#{@current_user.username}-#{Time.now.strftime("%y%m%d-%H%M%S")}"
      else
        "#{@entity.split('_').join('-')}-#{Time.now.strftime("%y%m%d-%H%M%S")}"
      end

      file = UserExport.create(file_name: file_name_prefix, user_id: @current_user.id)
      file_name = "#{file_name_prefix}-#{file.id}.csv"
      absolute_path = "#{UserExport.base_directory}/#{file_name}"

      # ensure directory exists
      FileUtils.mkdir_p(UserExport.base_directory) unless Dir.exists?(UserExport.base_directory)

      # write to CSV file
      CSV.open(absolute_path, "w") do |csv|
        csv << get_header
        send(export_method).each { |d| csv << d }
      end

      # compress CSV file
      `gzip -5 #{absolute_path}`

    ensure
      notify_user(file_name, absolute_path)
    end

    def user_archive_export
      return enum_for(:user_archive_export) unless block_given?

      Post.includes(topic: :category)
          .where(user_id: @current_user.id)
          .select(:topic_id, :post_number, :raw, :like_count, :reply_count, :created_at)
          .order(:created_at)
          .with_deleted
          .each do |user_archive|
        yield get_user_archive_fields(user_archive)
      end
    end

    def user_list_export
      return enum_for(:user_list_export) unless block_given?

      user_array = []
      user_field_ids = UserField.pluck(:id)

      condition = {}
      if @extra && @extra[:trust_level] && trust_level = TrustLevel.levels[@extra[:trust_level].to_sym]
        condition = { trust_level: trust_level }
      end

      if SiteSetting.enable_sso
        # SSO enabled
        User.where(condition).includes(:user_stat, :single_sign_on_record, :groups).find_each do |user|
          user_info_array = get_base_user_array(user)
          user_info_array = add_single_sign_on(user, user_info_array)
          user_info_array = add_custom_fields(user, user_info_array, user_field_ids)
          user_info_array = add_group_names(user, user_info_array)
          yield user_info_array
        end
      else
        # SSO disabled
        User.where(condition).includes(:user_stat, :groups).find_each do |user|
          user_info_array = get_base_user_array(user)
          user_info_array = add_custom_fields(user, user_info_array, user_field_ids)
          user_info_array = add_group_names(user, user_info_array)
          yield user_info_array
        end
      end
    end

    def staff_action_export
      return enum_for(:staff_action_export) unless block_given?

      staff_action_data = if @current_user.admin?
        UserHistory.only_staff_actions.order('id DESC')
      else
        UserHistory.where(admin_only: false).only_staff_actions.order('id DESC')
      end

      staff_action_data.each do |staff_action|
        yield get_staff_action_fields(staff_action)
      end
    end

    def screened_email_export
      return enum_for(:screened_email_export) unless block_given?

      ScreenedEmail.order('last_match_at DESC').each do |screened_email|
        yield get_screened_email_fields(screened_email)
      end
    end

    def screened_ip_export
      return enum_for(:screened_ip_export) unless block_given?

      ScreenedIpAddress.order('id DESC').each do |screened_ip|
        yield get_screened_ip_fields(screened_ip)
      end
    end

    def screened_url_export
      return enum_for(:screened_url_export) unless block_given?

      ScreenedUrl.select("domain, sum(match_count) as match_count, max(last_match_at) as last_match_at, min(created_at) as created_at")
                 .group(:domain)
                 .order('last_match_at DESC')
                 .each do |screened_url|
        yield get_screened_url_fields(screened_url)
      end
    end

    def report_export
      return enum_for(:report_export) unless block_given?

      @extra[:start_date]  = @extra[:start_date].to_date if @extra[:start_date].is_a?(String)
      @extra[:end_date]    = @extra[:end_date].to_date   if @extra[:end_date].is_a?(String)
      @extra[:category_id] = @extra[:category_id].to_i   if @extra[:category_id]
      @extra[:group_id]    = @extra[:group_id].to_i      if @extra[:group_id]
      Report.find(@extra[:name], @extra).data.each do |row|
        yield [row[:x].to_s(:db), row[:y].to_s(:db)]
      end
    end

    def get_header
      if @entity == 'user_list'
        header_array = HEADER_ATTRS_FOR['user_list'] + HEADER_ATTRS_FOR['user_stats']
        header_array.concat(HEADER_ATTRS_FOR['user_sso']) if SiteSetting.enable_sso
        user_custom_fields = UserField.all
        if user_custom_fields.present?
          user_custom_fields.each do |custom_field|
            header_array.push("#{custom_field.name} (custom user field)")
          end
        end
        header_array.push("group_names")
      else
        header_array = HEADER_ATTRS_FOR[@entity]
      end

      header_array
    end

    private

      def escape_comma(string)
        if string && string =~ /,/
          return "#{string}"
        else
          return string
        end
      end

      def get_base_user_array(user)
        user_array = []
        user_array.push(user.id,escape_comma(user.name),user.username,user.email,escape_comma(user.title),user.created_at,user.last_seen_at,user.last_posted_at,user.last_emailed_at,user.trust_level,user.approved,user.suspended_at,user.suspended_till,user.blocked,user.active,user.admin,user.moderator,user.ip_address,user.user_stat.topics_entered,user.user_stat.posts_read_count,user.user_stat.time_read,user.user_stat.topic_count,user.user_stat.post_count,user.user_stat.likes_given,user.user_stat.likes_received)
      end

      def add_single_sign_on(user, user_info_array)
        if user.single_sign_on_record
          user_info_array.push(user.single_sign_on_record.external_id,user.single_sign_on_record.external_email,user.single_sign_on_record.external_username,escape_comma(user.single_sign_on_record.external_name),user.single_sign_on_record.external_avatar_url)
        else
          user_info_array.push(nil,nil,nil,nil,nil)
        end
        user_info_array
      end

      def add_custom_fields(user, user_info_array, user_field_ids)
        if user_field_ids.present?
          user.user_fields.each do |custom_field|
            user_info_array << escape_comma(custom_field[1])
          end
        end
        user_info_array
      end

      def add_group_names(user, user_info_array)
        group_names = user.groups.each_with_object("") do |group, names|
          names << "#{group.name};"
        end
        user_info_array << group_names[0..-2] unless group_names.blank?
        group_names = nil
        user_info_array
      end

      def get_user_archive_fields(user_archive)
        user_archive_array = []
        topic_data = user_archive.topic
        user_archive = user_archive.as_json
        topic_data = Topic.with_deleted.find_by(id: user_archive['topic_id']) if topic_data.nil?
        return user_archive_array if topic_data.nil?
        category = topic_data.category
        sub_category = "-"
        if category
          category_name = category.name
          if !category.parent_category_id.nil?
            # sub category
            category_name = Category.find_by(id: category.parent_category_id).name
            sub_category = category.name
          end
        else
          # PM
          category_name = "-"
        end
        is_pm = topic_data.archetype == "private_message" ? I18n.t("csv_export.boolean_yes") : I18n.t("csv_export.boolean_no")
        url = "#{Discourse.base_url}/t/#{topic_data.slug}/#{topic_data.id}/#{user_archive['post_number']}"

        topic_hash = {"post" => user_archive['raw'], "topic_title" => topic_data.title, "category" => category_name, "sub_category" => sub_category, "is_pm" => is_pm, "url" => url}
        user_archive.merge!(topic_hash)

        HEADER_ATTRS_FOR['user_archive'].each do |attr|
          user_archive_array.push(user_archive[attr])
        end

        user_archive_array
      end

      def get_staff_action_fields(staff_action)
        staff_action_array = []

        HEADER_ATTRS_FOR['staff_action'].each do |attr|
          data =
            if attr == 'action'
              UserHistory.actions.key(staff_action.attributes[attr]).to_s
            elsif attr == 'staff_user'
              user = User.find_by(id: staff_action.attributes['acting_user_id'])
              user.username if !user.nil?
            elsif attr == 'subject'
              user = User.find_by(id: staff_action.attributes['target_user_id'])
              user.nil? ? staff_action.attributes[attr] : "#{user.username} #{staff_action.attributes[attr]}"
            else
              staff_action.attributes[attr]
            end

            staff_action_array.push(data)
        end
        staff_action_array
      end

      def get_screened_email_fields(screened_email)
        screened_email_array = []

        HEADER_ATTRS_FOR['screened_email'].each do |attr|
          data =
            if attr == 'action'
              ScreenedEmail.actions.key(screened_email.attributes['action_type']).to_s
            else
              screened_email.attributes[attr]
            end

          screened_email_array.push(data)
        end

        screened_email_array
      end

      def get_screened_ip_fields(screened_ip)
        screened_ip_array = []

        HEADER_ATTRS_FOR['screened_ip'].each do |attr|
          data =
            if attr == 'action'
              ScreenedIpAddress.actions.key(screened_ip.attributes['action_type']).to_s
            else
              screened_ip.attributes[attr]
            end

          screened_ip_array.push(data)
        end

        screened_ip_array
      end

      def get_screened_url_fields(screened_url)
        screened_url_array = []

        HEADER_ATTRS_FOR['screened_url'].each do |attr|
          data =
            if attr == 'action'
              action = ScreenedUrl.actions.key(screened_url.attributes['action_type']).to_s
              action = "do nothing" if action.blank?
            else
              screened_url.attributes[attr]
            end

          screened_url_array.push(data)
        end

        screened_url_array
      end

      def notify_user(file_name, absolute_path)
        if @current_user
          if file_name.present? && File.exists?("#{absolute_path}.gz")
            SystemMessage.create_from_system_user(
              @current_user,
              :csv_export_succeeded,
              download_link: "#{Discourse.base_uri}/export_csv/#{file_name}.gz",
              file_name: "#{file_name}.gz",
              file_size: number_to_human_size(File.size("#{absolute_path}.gz"))
            )
          else
            SystemMessage.create_from_system_user(@current_user, :csv_export_failed)
          end
        end
      end
  end
end