Splitting files into multiple, smaller files

split_files.rb

#!/usr/bin/env ruby

require 'pathname'
require 'csv'

if ARGV.empty? || ARGV[0].empty? || ARGV[1].empty?
  puts 'Usage: split <file> <number-of-files-to-create>'
end

file = begin
    Pathname.new(ARGV[0]).realpath
  rescue Errno::ENOENT
    raise "Path doesn't exist"
  end

working_dir = file.dirname
rows = File.readlines(file)
number_of_files_to_create = ARGV[1].to_i
number_of_rows_per_file = (rows.length / number_of_files_to_create).floor
counter = 1;

puts "------------------------"
puts "Number of rows per file: #{number_of_rows_per_file}"
puts "Number of files to create: #{number_of_files_to_create}"
puts "------------------------"

# This will create an additional file if
# number_of_rows_per_file has a modulo of != 0
while rows.length > 0 do
  output_file = CSV.open("#{working_dir}/#{counter}.csv", "w") do |csv|
    input = rows.pop(number_of_rows_per_file)
    input.each do |row|
      csv << [row.to_s.strip!]
    end
    counter += 1
    puts "Remaining: #{rows.length}"
  end
end