Example code: Helper methods used in `items/index.html.erb` and `items/show.html.erb` from www.speedie.equipment

items_helper.rb

module ItemsHelper

  def current_status_display_for_item(item)
    case item.service_events.order(:service_date, :created_at).last&.status
      when 'In Service'
        '<span class="badge badge-success">In Service</span>'.html_safe

      when 'Repair'
        '<span class="badge badge-warning">
          Repair
        </span>'.html_safe
      
      when 'Out of Service'
        '<span class="badge badge-danger">
          Out of Service
        </span>'.html_safe
      
      when 'Discarded'
        '<span class="badge badge-dark">
          Discarded
        </span>'.html_safe
      
      when 'Sold'
        '<span class="badge badge-secondary">
          Sold
        </span>'.html_safe

      when 'Missing'
        '<span class="badge badge-primary">
          Missing
        </span>'.html_safe
    end
  end

  
  def next_calibration_due_for_item(item)
    item.calibration_events.order(:date_performed, :created_at).last&.date_performed >> 
      item.item_type.calibration_interval_in_months
  end

  
  def next_calibration_due_display_for_item(item)
    case item.service_events.order(:service_date, :created_at).last&.status
      
      when 'In Service'
        if item.calibration_events.any?
          if item.service_events.order(:service_date, :created_at).last&.service_date > 
            item.calibration_events.order(:date_performed, :created_at).last&.date_performed &&
            item.service_events.count > 1
              '<span class="font-weight-bold text-danger">
                Calibration Required To Bring Back In Service
              </span>'.html_safe
          else
            '<span class="font-weight-bold">
              Next Due: 
            </span>'.html_safe + 
              (item.calibration_events.order(:date_performed, :created_at).last&.date_performed >>
                item.item_type.calibration_interval_in_months).strftime("%m/%d/%Y")
          end
        else
          '<span class="font-weight-bold text-danger">
            No Calibration Record Exists Yet
          </span>'.html_safe
        end

      when 'Repair'
        if item.calibration_events.any?
          if item.service_events.order(:service_date, :created_at).last&.service_date > 
            item.calibration_events.order(:date_performed, :created_at).last&.date_performed &&
            item.service_events.count > 1
              '<span class="font-weight-bold text-danger">
                Calibration Required To Bring Back In Service
              </span>'.html_safe
          else
            '<span class="font-weight-bold">
              Next Due: 
            </span>'.html_safe + 
              (item.calibration_events.order(:date_performed, :created_at).last&.date_performed >>
                item.item_type.calibration_interval_in_months).strftime("%m/%d/%Y")
          end
        else
          '<span class="font-weight-bold text-danger">
            No Calibration Record Exists Yet
          </span>'.html_safe
        end

      when 'Missing'
        if item.calibration_events.any? 
          '<span class="font-weight-bold">
            Next Due: 
          </span>'.html_safe +
            (item.calibration_events.order(:date_performed, :created_at).last&.date_performed >>
              item.item_type.calibration_interval_in_months).strftime("%m/%d/%Y")
        else
          '<span class="font-weight-bold text-danger">
            No Calibration Record Exists Yet
          </span>'.html_safe
        end

      when 'Out of Service'
        '<span class="font-weight-bold text-info">
          Calibration Requried When Brought Back Into Service
        </span>'.html_safe

      when 'Discarded'
        
      when 'Sold'

    end
  end

  
  def overdue_for_calibration_display_for_item(item)
    if item.calibration_events.any? && 
      item.service_events.order(:service_date, :created_at).last&.status == 'In Service' 
      && (DateTime.now.to_date > 
      (item.calibration_events.order(:date_performed, :created_at).last&.date_performed >> 
        item.item_type.calibration_interval_in_months))
        '<span class="font-weight-bold text-danger">  << Overdue!!</span>'.html_safe
    end
  end

  
  def sieve_diameter_display_for_item(item)
    case item.sieve_diameter
      when '18 inch'
        '18"'
      when '12 inch'
        '12"'
      when '8 inch'
        '8"'
      when '3 inch'
        '3"'
      when 'Gilson'
        'Gilson'
    end
  end

  
  # View helpers for displaying all the variables
  # associated with certain item_types
  def item_type_variables_suffix_display_for_item(item)
    if item.has_item_type_variables == true
      case item.item_type.name
        when 'Sieve'
          sieve_diameter_display_for_item(item)
        when 'Saw'
          item.saw_type
        when 'Caliper'
          item.caliper_type
        when 'Penetrometer'
          item.penetrometer_type
        when 'Proctor Hammer'
          item.proctor_hammer_weight
        when 'Flask'
          item.flask_type
      end
    end
  end

  
  def item_type_variables_affix_display_for_item(item)
    if item.has_item_type_variables == true
      case item.item_type.name
        when 'Sieve'
          if item.sieve_type == 'Fine'
            '(' + item.fine_sieve_opening_size + ')'
          else
            '(' + item.coarse_sieve_opening_size + ')'
          end
        when 'Flask'
          '(' + item.volume + ')'
        when 'Proctor Mold 4"'
          '(' + item.proctor_mold_type + ')'
        when 'Proctor Mold 6"'
          '(' + item.proctor_mold_six_type + ')'
        when 'Scale'
          '(' + item.scale_resolution + ' res; ' + item.scale_range + ' max)'
        when 'Capping Mold'
          '(' + item.capping_mold_size + ')'
        when 'Groove Tool'
          '(' + item.groove_tool_type + ')'
        when 'Marshall Hammer'
          '(' + item.operation_type + ')'
        when 'Marshall Pedestal'
          '(' + item.marshall_compaction_pedestal_number + ')'
        when 'Thermometer'
          '(' + item.thermometer_type + ')'
        when 'Caliper'
          '(' + item.caliper_size + ')'
        when 'Gauge'
          '(' + item.gauge_type + ')'
      end
    end
  end

  
  def meets_spec_icon_display_for_item(item)
    if item.meets_specifications?
      fa_icon 'check-circle', class: 'text-success'
    else
      fa_icon 'times-circle', class: 'text-danger'
    end
  end
end