Mac Battery Capacity

inspect.rb

#!/usr/bin/ruby

require 'nokogiri'
  
ioreg = IO::popen("ioreg -a -c AppleSmartBattery", "r")
doc = Nokogiri::XML(ioreg)
ioreg.close

cc=doc.xpath("//key[text()=\"CurrentCapacity\"]")[0]

node = cc
while true
  printf "%s\n", node.name
  if node.name == "dict"
    ioobjectclass = node.xpath("./key[text()=\"IOObjectClass\"]")
    # puts ioobjectclass.length
    if ioobjectclass.length>0
      printf "  %s\n", ioobjectclass[0].next_element.text
    end
  end
  break if node.name == "document"
  node = node.parent
end

main.rb

#!/usr/bin/ruby

require 'nokogiri'
require 'optparse'


opt = OptionParser.new

wait_sec = 60
opt.on('-i wait') do |wait_str|
  wait_sec = wait_str.to_i
end

count = 1
opt.on('-c count') do |count_str|
  count = count_str.to_i
end

opt.parse!(ARGV)

count_current = 0
while true

  time_now = Time::now.to_i
  
  ioreg = IO::popen("ioreg -a -c AppleSmartBattery", "r")
  doc = Nokogiri::XML(ioreg)
  ioreg.close
  
  smb=doc.xpath("//dict[./key[text()=\"IOObjectClass\" and following-sibling::string[1][text()=\"AppleSmartBattery\"] ]]")
  
  # puts current = smb.xpath("./key[text()=\"CurrentCapacity\"]/following::integer[1]")[0].text
  current = smb.xpath("./key[text()=\"CurrentCapacity\"]")[0].next_element.text.to_i
  max = smb.xpath("./key[text()=\"MaxCapacity\"]")[0].next_element.text.to_i
  design = smb.xpath("./key[text()=\"DesignCapacity\"]")[0].next_element.text.to_i
  
  printf "%d\t%.1f %.1f\t%d %d %d\n", time_now, (current*100.0/max), (current*100.0/design), current, max, design
  $stdout.flush
  count_current += 1
  
  break if count>0 && count_current == count
  sleep wait_sec
end