class IPScanner

# File lib/ipscanner.rb, line 48
def self.autodetect_new(ip_base=nil, lapse: 30, &blk)        
  
  ip_base = local_ip.ip_address[/\d+\.\d+\.\d+\./] unless ip_base
  
  puts "scanning the network (#{ip_base}x)"

  a1 = scan ip_base
  puts "found %d IP addresses" % a1.length
  
  
  loop do
    
    sleep lapse
    a2 = scan ip_base
    found = a2 - a1
    blk.call(found) if found.any?
    a1 = a2

  end
  
end

# File lib/ipscanner.rb, line 10
def self.detect_new(ip_base=nil)
  
  ip_base = local_ip.ip_address[/\d+\.\d+\.\d+\./] unless ip_base
  
  puts "scanning the network (#{ip_base}x)"

  a1 = scan ip_base
  puts "found %d IP addresses" % a1.length
  k = :y

  while k == :y do

    print 'scan to detect new IP addresses? (y/n) '
    k = gets.lstrip.chomp.to_sym
    (puts 'enter y or n'; k = :y) if k != :y and k != :n
    
    return if k == :n
    
    a2 = scan ip_base
    found = a2 - a1
    
    if a2 == a1 then
      puts 'no new IP addresses found'
    else
      if found.any? then
        puts 'found : ' + found.inspect 
      else
        puts "found %d IP addresses" % a1.length
      end
    end
    
    a1 = a2

  end

  
end

# File lib/ipscanner.rb, line 70
def self.local_ip()
  Socket.ip_address_list.find { |ai| ai.ipv4? && !ai.ipv4_loopback? }
end

# File lib/ipscanner.rb, line 85
def self.pingecho(host, timeout=5, service="echo")
  begin
    Timeout.timeout(timeout) do
    s = TCPSocket.new(host, service)
    s.close
    end
  rescue Errno::ECONNREFUSED
    return true
  rescue Timeout::Error, StandardError
    return false
  end
  return true
end

# File lib/ipscanner.rb, line 74
def self.scan(ip_base=nil, range=1..254, t=1)
  
  ip_base = local_ip.ip_address[/\d+\.\d+\.\d+\./] unless ip_base    
  
  a = []
  (range).map{|i| Thread.new {a << i if pingecho(ip_base+i.to_s, t) }}.join
  sleep t + 0.25
  
  a.sort.map{|x| ip_base + x.to_s}
end