murder

#!/usr/bin/env ruby

SIGNALS = [
  [15, 3],
  [2, 3],
  [1, 4],
  [9, 0]
]

def i?(arg)
  arg.to_i != 0
end

def running?(pid)
  `ps -p #{pid}`.lines.length == 2
end

def go_ahead?
  %w(y yes yas).include? $stdin.gets.strip.downcase
end

def kill(pid, code)
  `kill -#{code} #{pid}`
end

def murder_pid(pid)
  SIGNALS.each do |signal|
    break unless running? pid

    code, wait = signal

    kill(pid, code)
    sleep 0.5
    sleep(wait) if running? pid
  end
end

def murder_names(name)
  running = `ps -eo 'pid command' | grep -Fiw '#{name}' | grep -Fv grep`
  running.lines.each do |line|
    pid, fullname = line.split(nil, 2)

    next if Process.pid == pid.to_i

    print "murder #{fullname.chomp} (pid #{pid})? "
    murder_pid(pid) if go_ahead?
  end
end

def murder_port(arg)
  lsofs = `lsof -i #{arg}`
  lsofs.lines.drop(1).each do |line|
    pid = line.split(nil, 3)[1]

    fullname = `ps -eo 'command' #{pid}`.lines.drop(1).first

    print "murder #{fullname.chomp} (pid #{pid})? "
    murder_pid(pid) if go_ahead?
  end
end

def main(arg)
  is_pid = i?(arg)
  is_port = arg[0] == ':' && i?(arg.slice(1, arg.size))

  if is_pid
    murder_pid arg
  elsif is_port
    murder_port arg
  else
    murder_names arg
  end
end

if ARGV.size < 1
  puts 'usage:'
  puts 'murder 123    # kill by pid'
  puts 'murder ruby   # kill by process name'
  puts 'murder :3000  # kill by port'
  exit 1
else
  main(ARGV[0])
end