enrollments_datatable.rb

class EnrollmentsDatatable
  delegate :edit_enrollment_path,:image_url,:image?,:image_tag,:params, :h, :link_to, :number_to_currency, to: :@view

  def initialize(view)
    @view = view
  end

  def as_json(options = {})
    {
      sEcho: params[:sEcho].to_i,
      iTotalRecords: Enrollment.count,
      iTotalDisplayRecords: enrollments.total_entries,
      aaData: data
    }
  end

private

  def data
    enrollments.map do |enrollment|
      
      [ image_tag(enrollment.image? ? enrollment.image_url(:thumb) : "/assets/icons/unavl.jpg",:size => "50x50") ,
        "<div class='main-name'>" + 
        link_to(enrollment.first_name + " " + enrollment.sur_name,enrollment) + 
        " " +
        link_to("followup", {:action => "new",
                            :controller => "events", 
                            :enrollment_id => enrollment.id},{:class => "tools-text"}) + 
        "</div>",
        enrollment.email,
        enrollment.mobile_phone,
        enrollment.education_level,
        enrollment.gender + " - " + enrollment.marital_status,
        enrollment.passport_number,
        "<div class = 'tools dn'> <ul>" + 
        ["<li>" + 
        link_to(image_tag("/assets/icons/view.png"),enrollment) + 
        "</li>", "<li>" + 
        link_to(image_tag("/assets/icons/edit.png"), edit_enrollment_path(enrollment) ) + 
        "</li>", "<li>" + 
        link_to(image_tag("/assets/icons/delete.png"),enrollment,method: :delete, data: { confirm: 'Are you sure?' }) + 
        "</li>"].join("  ") + 
        "</ul> </div>"
        ]
    end
  end

  def enrollments
    @enrollments ||= fetch_enrollments
  end

  def fetch_enrollments
    enrollments = Enrollment.order("#{sort_column} #{sort_direction}")
    enrollments = enrollments.page(page).per_page(per_page)
    if params[:sSearch].present?
      enrollments = enrollments.where("first_name like :search or sur_name like :search", search: "%#{params[:sSearch]}%")
    end
    enrollments
  end

  def page
    params[:iDisplayStart].to_i/per_page + 1
  end

  def per_page
    params[:iDisplayLength].to_i > 0 ? params[:iDisplayLength].to_i : 10
  end

  def sort_column
    columns = %w[first_name ]
    columns[params[:iSortCol_1].to_i]
  end

  def sort_direction
    params[:sSortDir_0] == "desc" ? "desc" : "asc"
  end
end