module RailsAdminContent
  class Paginate
    
    def initialize(scope, options = {})
      @scope, @options = scope, options
    end

    def to_s
      return "" unless @scope
      current_page, total_pages = @options[:spage].to_i, RailsAdminContent::Client.total_nums / @options[:stint] + 1
      # return "共#{RailsAdminContent::Client.total_nums}条数据" if total_pages <= 1
      param_name = @options["param_name"] || "page"
      url = @options["url"] || ""
      helpers.content_tag :div, :class => "pagination" do
        helpers.content_tag :ul do
          result = ''
          result += helpers.content_tag(:li, class: 'previous'){helpers.link_to("‹ 上一页","#{url}?#{param_name}=#{current_page-1}")} if current_page.to_i > 1
          if total_pages > 8
            1.upto(3) { |i| result << page_link(i, current_page) }
            if current_page > 1 and current_page < total_pages
              result << helpers.content_tag(:li, helpers.link_to("...",'#'), class: 'disabled') if current_page > 5
              min = current_page > 4 ? current_page-1 : 4
              max = current_page < total_pages-4 ? current_page+2 : total_pages-2
              (min..max-1).each { |i| result << page_link(i, current_page) } if max >= min+1
              result << helpers.content_tag(:li, helpers.link_to("...", "#"), class: 'disabled') if current_page < total_pages-4
            else
              result << helpers.content_tag(:li, helpers.link_to("...",'#'), class: 'disabled')
            end
            (total_pages-2..total_pages).each{ |i| result << page_link(i, current_page) }
          else
            (1..total_pages).each{ |i| result << page_link(i, current_page) }
          end
          result += helpers.content_tag(:li, class: "next"){helpers.link_to("下一页 ›", "#{url}?#{param_name}=#{current_page+1}")} if current_page < total_pages
          result += helpers.content_tag(:li, class: 'disabled total_pages'){helpers.link_to "共#{RailsAdminContent::Client.total_nums}条数据", "#"}
          result.html_safe
        end
      end
     
    end

    private
    def page_link(page, current_page)
      param_name = @options["param_name"] || "page"
      url = @options["url"] || ""
      current_page == page ? helpers.content_tag(:li, page, :class => "active"){helpers.link_to page, '#'} : helpers.content_tag(:li, helpers.link_to("#{page}", "#{url}?#{param_name}=#{page}"))
    end

    def helpers
      ActionController::Base.helpers
    end   
    
  end
end