module Hooray
  #
  # Main runner
  #
  class Seek
    attr_accessor :network, :opts, :nodes

    NET_MASK = 24
    TIMEOUT  = 1

    def initialize(network = nil, *params)
      @network = network || Seek.local_mask
      set_query(params)
      set_nodes
    end
    alias_method :devices, :nodes

    #
    # Form need params based on user input
    #
    def set_query(params)
      return if params.empty?
      ports, words = params.flatten.partition { |s| s =~ /\d+/ }
      @ports = ports.map(&:to_i).first # TODO
      @protocol = words.select { |w| w =~ /udp|tcp/ }.join
    end

    #
    # Map results to @nodes << Node.new()
    #
    # BUG: sometimes ping returns true
    # When you run list consecutively. Pretty weird!
    # So we need to remove those without mac
    def set_nodes
      @nodes = ping.sort.map do |n|
        Node.new(ip: n, mac: arp_table[n.to_s]) # , name: find_name(n))
      end.reject { |n| n.mac.nil? } # remove those without mac
    end

    def ping_class
      return Net::Ping::External unless @protocol
      @protocol =~ /udp/ ? Net::Ping::UDP : Net::Ping::TCP
    end

    #
    # fast -> -sn -PA
    #
    def ping
      scan = []
      bots = []
      # pa "Starting #{Settings.list} on '#{network}' #{@ports} #{@protocol}"
      @network.to_range.each do |ip|
        # next if ip == my_lan_ip
        bots << Thread.new do
          if ping_class.new(ip.to_s, @ports, TIMEOUT).ping?
            scan << ip
            print '.'
          end
        end
      end
      bots.each(&:join)
      puts
      scan
    end

    #
    # ARP Table reader
    #
    def arp_table
      return @arp_table if @arp_table
      @arp_table ||= {}
      `arp -na`.split(/\n/).each do |l|
        _q, ip, _at, mac, *iface = l.split(/\s+/)
        next unless mac =~ /:\w{2}:/
        ip = ip[1..-2] # (ip) -> ip
        @arp_table.merge!(ip => mac) if iface
      end
      @arp_table
    end

    class << self
      def my_ips
        Socket.ip_address_list.select do |ip|
          ip.ipv4_private? && !ip.ipv4_loopback?
        end
      end

      def my_lan_ip
        IPAddr.new(my_ips.first.ip_address)
      end

      def local_mask
        my_lan_ip.mask(NET_MASK)
      end
    end
  end
end