f_dur.rb

def format_duration(n)
  return "now" if n == 0
  return "#{n} second" if n == 1
  return "#{n} seconds" if n.between?(2, 59)

  minutes, seconds = n.divmod(60)
  hours, minutes = minutes.divmod(60)
  days, hours = hours.divmod(24)
  years, days = days.divmod (365)


#  if [years, days, hours, minutes, seconds].each {|value| value > 1}
#    str_out = "%d years, %d days, %d hours, %d minutes and %d seconds" % [years, days, hours, minutes, seconds]
#  end

  tri_years, tri_days, tri_hours, tri_minutes, tri_seconds = 0

  case years
  when years == 0
    tri_years = 0 # the unit, years/year would then not be used for output
  when years == 1
    tri_years = 1 # the unit, year would be used for output
  else
    tri_years = 2 # the unit, years would be used for output
  end

  case days
  when days == 0
    tri_days = 0
  when days == 1
    tri_days = 1
  else
    tri_days = 2
  end

  case hours
  when hours == 0
    tri_hours = 0
  when hours == 1
    tri_hours = 1
  else
    tri_hours = 2
  end

  case minutes
  when minutes == 0
    tri_minutes = 0
  when minutes == 1
    tri_minutes = 1
  else
    tri_minutes = 2
  end

  case seconds
  when seconds == 0
    tri_seconds = 0
  when seconds == 1
    tri_seconds = 1
  else
    tri_seconds = 2
  end

  plural_singular_arr = []
  plural_singular_arr << "seconds" if tri_seconds == 2
  plural_singular_arr << "second" if tri_seconds == 1
  plural_singular_arr << "minutes" if tri_minutes == 2
  plural_singular_arr << "minute" if tri_minutes == 1
  plural_singular_arr << "hours" if tri_hours == 2
  plural_singular_arr << "hour" if tri_hours == 1
  plural_singular_arr << "days" if tri_days == 2
  plural_singular_arr << "day" if tri_days == 1
  plural_singular_arr << "years" if tri_years == 2
  plural_singular_arr << "year" if tri_years == 1

  units_arr = []
  units_arr << "seconds" if tri_seconds != 0
  units_arr << "minutes" if tri_minutes != 0
  units_arr << "hours" if tri_hours != 0
  units_arr << "days" if tri_days != 0
  units_arr << "years" if tri_years != 0

  puts tri_years # Clearly I don't understand Ruby's case syntax, when n == 60 (among tons of other values) this returns 2
  if units_arr.length == 1
    return "#{units_arr.map {|unit| binding.local_variable_get unit} }"
  end

  ""
end

puts format_duration(63252122)

TIME_UNITS = [60, 60, 24, 365]
TIME_NAMES = [:seconds, :minutes, :hours, :days, :years]

def seconds_to_units(seconds, time_units = TIME_UNITS)
  time_units.reduce([seconds]) { |time_stack, unit_size|
    time_stack.concat(time_stack.pop.divmod(unit_size).reverse)
  }
end

time_array = seconds_to_units(1_000_000)
# => [40, 46, 13, 11, 0]
TIME_NAMES.zip(time_array).to_h
# => {:seconds=>40, :minutes=>46, :hours=>13, :days=>11, :years=>0}