module Moderator
  class IpAddrSearch
    attr_reader :params, :errors

    def initialize(params)
      @params = params
      @errors = []
    end

    def execute
      if params[:user_id].present?
        search_by_user_id(params[:user_id].split(/,/))
      elsif params[:user_name].present?
        search_by_user_name(params[:user_name].split(/,/))
      elsif params[:ip_addr].present?
        search_by_ip_addr(params[:ip_addr].split(/,/))
      else
        []
      end
    end

  private
    def select_all_sql(sql, *params)
      ActiveRecord::Base.select_all_sql(sql, *params)
    end

    def search_by_ip_addr(ip_addrs)
      sums = Hash.new {|h, k| h[k] = 0}

      add_row(sums, "select creator_id as k, count(*) from comments where ip_addr in (?) group by k", ip_addrs)
      add_row(sums, "select updater_id as k, count(*) from post_versions where updater_ip_addr in (?) group by k", ip_addrs)
      add_row(sums, "select updater_id as k, count(*) from note_versions where updater_ip_addr in (?) group by k", ip_addrs)
      add_row(sums, "select updater_id as k, count(*) from pool_versions where updater_ip_addr in (?) group by k", ip_addrs)
      add_row(sums, "select updater_id as k, count(*) from wiki_page_versions where updater_ip_addr in (?) group by k", ip_addrs)

      sums
    end

    def search_by_user_name(user_names)
      users = User.where("name in (?)", user_names)
      search_by_user_id(users.map(&:id))
    end

    def search_by_user_id(user_ids)
      sums = Hash.new {|h, k| h[k] = 0}

      add_row(sums, "select ip_addr as k, count(*) from comments where creator_id in (?) group by k", user_ids)
      add_row(sums, "select updater_ip_addr as k, count(*) from post_versions where updater_id in (?) group by k", user_ids)
      add_row(sums, "select updater_ip_addr as k, count(*) from note_versions where updater_id in (?) group by k", user_ids)
      add_row(sums, "select updater_ip_addr as k, count(*) from pool_versions where updater_id in (?) group by k", user_ids)
      add_row(sums, "select updater_ip_addr as k, count(*) from wiki_page_versions where updater_id in (?) group by k", user_ids)

      sums
    end

    def add_row(sums, sql, ip_addrs)
      select_all_sql(sql, ip_addrs).each do |row|
        sums[row["k"]] += row["count"].to_i
      end
    end
  end
end