#!/usr/bin/env ruby

STDOUT.sync = true

require 'json'

target_key = ARGV[0] || 'timestamp'

previous_time = nil

STDIN.each_line do |line|
  begin
    object = JSON.parse(line)

    unless previous_time
      puts line.chomp
      if object.keys.include?(target_key)
        previous_time = object[target_key]
      end
      next
    end

    if object.keys.include?(target_key)
      sleep object[target_key] - previous_time
      puts line.chomp
    end

    previous_time = object[target_key]

  rescue => error
    next
  end
end