YAML Hours Tracker

hours.rb

#!/usr/bin/env ruby
require 'date'
require 'yaml'

class Float
  def nearest_half
    (self * 2.0).ceil / 2.0
  end
end

class String
  def time_range_to_f
    parts = self.split('-')
    start = DateTime.parse(parts.first)
    finish = DateTime.parse(parts.last)
    (finish - start).to_f * 24.0
  end
end

if ARGV.size < 1
  $stderr.puts "Usage: #{__FILE__} <month>.yml"
  exit 1
end

month = ARGV.first.split('.')[0..-2].join.capitalize
puts "Hours for the month of #{month}:"
puts

YAML.load_file(ARGV.first).each do |date, hours|
  total = hours.map(&:time_range_to_f).reduce(&:+).nearest_half
  puts "#{month} #{date}: #{total} hours"
end