functional-ish.rb

class LinePresenter
  def initialize(object)
    @object = object
  end

  def to_s
    "Office: #{@object.office}, Employee ID: #{@object.employee_id}, First name: #{@object.first_name}"
  end
end

class Line

  attr_reader :line

  def initialize(text:)
    @line = text
  end

  def office
    values[2].strip
  end

  def employee_id
    values[1].strip
  end

  def first_name
    name = values[0]
    name.split[0]
  end

  private

    def values
      @values ||= line.split(',')
    end

end

File.open('timesheets.txt', 'r') do |file|
  file.
    each_line.
    lazy.
    map {|text| Line.new(text: text)}.
    map {|line| LinePresenter.new(line)}.
    each {|line| puts line}
end

timesheets.txt

Tony Stark, 1111, Desio, x1
Barry Allen, 2222, Desio, x2
Bruce Wayne, 3333, Desio, x3
Kal El, 4444, Desio, x4