# encoding: utf-8
module Mutx
  module Support
    class Processes

      def self.kill_by_result_id(result_id)

        pid = pid_for(result_id)

        return false if pid.nil?

        childs = process_childs(pid)

        unless pid.zero?
          begin
            childs.each{|ch_pid| kill_p(ch_pid)} unless childs.empty?
            kill_p(pid)
            true # Process killed
          rescue Errno::EPERM # Denied permission to kill process
            begin
              kill_dash_nine(pid) and true # Process killed
            rescue
              false
            end
          rescue Errno::ESRCH # Process did not exist
            false
          end
        else
            puts "Cannot find process id"
        end
      end

      def self.kill_p(pid)
        return false if pid.nil?
        pid = pid.to_i if pid.respond_to? :to_i
        begin
          Process.kill('INT', pid) and true
        rescue => e
          puts "#{e} [#{pid}]"
          false
        end
      end

      def self.kill_dash_nine(pid)
        pid = pid.to_i if pid.respond_to? :to_i
        puts "kill -9 #{pid}" if $DEBUG
        Mutx::Support::Console.execute "kill -9 #{pid}"
      end

      def self.pid_for(result_id)
        result = Mutx::Results::Result.get(result_id)
        result.pid.to_i
      end

      def self.process_running? pid
        unless pid.nil?
          res = Mutx::Support::Console.execute("ps -p #{pid}").split("\n").last
          unless res.nil?
            res.include? "#{pid}" and !res.include? "<defunct>"
          end
        end
      end


      #Recibe un PID y devuelve un array con los PID de sus hijos
      def self.process_childs(pid)
        res = Mutx::Support::Console.execute("ps -fea | grep #{pid} | grep -v grep | awk '$2!=#{pid} && $8!~/awk/ && $3==#{pid}{print $2}'")
        File.open("#{__FILE__}#{__LINE__}","a+"){|f| f.write res}
        res
      end

      def self.mutx_pids
        res = Mutx::Support::Console.execute "ps -fea | grep 'unicorn.rb -p #{Mutx::Support::Configuration.port}'"
        res.split("\n").select{|lines| !lines.include? "grep"}.map{|line| line.split[1]}
      end

      # Returns a list of sidekiq pids
      # @return [Array]
      def self.sidekiq_pids
        res = Mutx::Support::Console.execute "ps -fea | grep 'sidekiq'"

        res.split("\n").select{|lines| !lines.include? "grep"}.map{|line| line.split[1]}
      end

      def self.kill_all_these pids=nil
        if pids
          until pids.empty?
            pid = pids.pop
            if process_running? pid
              begin
                kill_dash_nine(pid)
              rescue Errno::ESRCH
                puts "Could not find process id #{pid} to kill"
              end
            end
          end
        end
      end


      def self.fork_this command
        fork{exec("#{command}")}
      end


    end
  end
end