Step timer that predicts how long something will take to complete based on measurements of how long each step is taking you

step_timer.rb

#!/usr/bin/env ruby

# provides a basic timer, and predicts how long something will take you based on how long each individual step is taking you.

# Parameters:
# timer [num_steps=100] [at_steps]

def main
  
total_steps = 100;
at_step = 1
if ARGV.count>0
  total_steps = ARGV[0].to_i
  if ARGV.count>1
    at_step = ARGV[1].to_i
  end
end

num_steps = total_steps-at_step+1
puts "Number of steps: #{total_steps}"
puts "Starting at step #{at_step} (#{num_steps} remaining)"
puts ""
puts "At 30 seconds per step,"
estimate_total_time([30],num_steps)

sec_per_step = []

puts "Press enter to start timing"
STDIN.gets

done = false
while !done do
  start = Time.now
  puts "STEP #{at_step + sec_per_step.count}"
  puts "Press enter to stop timing, b to take a break (ie. stop timer, dont count), enter exit, x or q to quit"
  c = STDIN.gets
  if (c =~ /^b/i)
    puts "Taking a break! Press enter to restart"
    STDIN.gets
  else
    stop = Time.now
    diff = (stop - start).round
    puts "That took you #{diff} seconds"
    sec_per_step << diff
    estimate_total_time(sec_per_step, num_steps)
    puts "*******************************************************"
    done = (c=~/^exit|^x$|^q$/i)
  end
end
puts "AlL DONE!"
summary(sec_per_step, num_steps)
end

def mean(sec_per_step)
  sec_per_step.inject(0,:+) / sec_per_step.count
end

def estimate_total_time(sec_per_step, num_steps)
  # mean or median could be useful
  # lets start with mean
  
  steps_remaining = num_steps - sec_per_step.count
  
  estimated_sec_remaining = steps_remaining * mean(sec_per_step)
  
  puts "#{steps_remaining} steps should take you #{sec_to_minutes_and_seconds(estimated_sec_remaining)}"
  estimated_sec_remaining
end

def sec_to_minutes_and_seconds(sec)
  hours = (sec.to_i / 3600 )
  minutes = (sec.to_i % 3600 / 60)
  seconds = (sec.to_i % 3600 % 60)
  if hours>0
    "#{hours} hours, #{minutes} minutes and #{seconds} seconds"
  else
    "#{minutes} minutes and #{seconds} seconds"
  end
end

def summary(sec_per_step, num_steps)
  puts "You did #{sec_per_step.count} steps of #{num_steps} (#{sec_per_step.count * 100 / num_steps} %)"
  puts "Mean time per step = #{mean(sec_per_step)}"
  puts "Max time = #{sec_to_minutes_and_seconds(sec_per_step.max)}"
  puts "Min time = #{sec_to_minutes_and_seconds(sec_per_step.min)}"
end

main