# frozen_string_literal: true
module ZombieCheck
  module Ping
    class Checker
      attr_accessor :hosts_file, :delay, :hosts, :report, :interrupted

      def initialize(options = {})
        @hosts_file ||= options[:hosts_file] || "hosts.txt"
        @delay ||= (options[:delay] || 1000).to_i / 1000.0
        @hosts ||= []
        @report = CheckerReport.new
        setup_interruptor
      end

      def start
        puts "Using file #{hosts_file}, delay #{delay}, for exit press Ctrl+C"
        loop do
          update_hosts!
          @hosts.each { |host| Thread.new { ping host } }
          if interrupted
            exit_all_threads!
            puts @report.generate
            exit 0
          end
          sleep @delay
        end
      end

      def ping(host)
        icmp = Net::Ping::ICMP.new(host)
        icmp.ping
        @report << icmp
      end

      private

        def update_hosts!
          check_file_exists! hosts_file_path
          result = File.open(hosts_file_path, "r") { |f| f.readlines.map(&:chomp) }
          check_result_not_empty! result
          @hosts = result
        end

        def check_file_exists!(file)
          return if File.exist?(file)
          puts "No #{@hosts_file} file"
          exit 0
        end

        def check_result_not_empty!(result)
          return unless result.empty? && @hosts.empty?
          puts "#{@hosts_file} is empty"
          exit 0
        end

        def hosts_file_path
          File.expand_path(@hosts_file)
        end

        def setup_interruptor
          trap("INT") { @interrupted = true }
        end

        def exit_all_threads!
          Thread.list.reject { |t| t == Thread.current }.each(&:exit)
        end
    end
  end
end