#!/usr/bin/env ruby
# ncping [HOSTS...] - parallel ping with UTF-8 graphs
# Use -4 / -6 to toggle between ping/ping6 for the next hosts.
#
# Written by Christian Neukirchen <http://purl.org/net/chneukirchen>.
# ncping is in the public domain.
#
# To the extent possible under law, the creator of this work has
# waived all copyright and related or neighboring rights to this work.
# http://creativecommons.org/publicdomain/zero/1.0/

Thread.abort_on_exception = true

class Ping
  attr_reader :host, :ping

  def initialize(host, opts={})
    @host = host
    @width = opts[:width] || 60
    @buffer = opts[:buffer] || 60**3
    @backlog = Array.new(@buffer)
    @ping = opts[:ping] || "ping"
  end

  def run
    loop {
      IO.popen([@ping, "-DO", @host, :err=>[:child, :out]]) { |rd,wr|
        while line = rd.gets
          if line =~ /^connect: Network is unreachable/
            # e.g. dns failed, restart ping
            @backlog.shift
            @backlog << :down
            sleep 1
            break
          elsif line =~ /^\[([\d.]+)\].*time=([\d.]+)/
            ts, delay = $1.to_f, $2.to_f
            @backlog.shift
            @backlog << delay
          elsif line =~ /^\[([\d.]+)\].*no answer yet/
            @backlog.shift
            @backlog << :loss
          elsif line =~ /Network is unreachable/
            @backlog[-1] = :down
          end
        end
      }
    }
  end
  
  SYMBOLS = "\u2581\u2581\u2582\u2583\u2584\u2585\u2586\u2587\u2587"
  COLORS = %W{\e[1;32m \e[1;32m \e[0;32m \e[1;33m \e[0;33m \e[0;31m \e[1;31m \e[1;32m}
  OFFSETS = [   0.08,   5,    12,    25,    50,    100,    250,   1000   ]

  def avg(v)
    v.empty? ? 0 : v.inject(:+) / v.size
  end

  def stat(v)
    v2 = v.compact.find_all{|x| x!=:loss && x!=:down}
    [v2.min || 0.0, avg(v2), v2.max || 0.0]
  end

  def to_s(res=1)
    v = aggreg(res)
    min, avg, max = stat(v)

    line = v.last(@width).map { |d|
      if d == :loss
        "\e[1;30mx"
      elsif d == :down
        "\e[1;30mD"
      elsif d
        c = COLORS[OFFSETS.index { |cc| d < cc } || COLORS.size-1]
        
        if max == min
          c + SYMBOLS[SYMBOLS.size/2]
        else
          c + SYMBOLS[(((d-min) / (max-min))*SYMBOLS.size - 0.5).to_i]
        end
      else
        "\e[0;37m\u00B7"
      end
    }.join
  
    "\e[0;37m%s%s%s %s\e[0;37m" % [fmt(min), fmt(avg), fmt(max), line]
  end

  def fmt(ms)
    if ms >= 100_000
      "%5.0fs" % (ms/1000)
    elsif ms >= 10_000
      "%5.1fs" % (ms/1000)
    elsif ms >= 1000
      "%5.2fs" % (ms/1000)
    else
      "%6.1f" % ms
    end
  end

  def aggreg(res)
    @backlog.last(res*@width).each_slice(res).map { |s| char s }
  end

  def char(ary)
    if ary.count(:down) == ary.size
      :down 
    elsif ary.size > 0 && ary.count(:loss).to_f / ary.compact.size >= 0.05
      :loss
    elsif ary.count(nil) == ary.size
      nil
    else
      avg(ary.grep(Numeric))
    end
  end

  def desc
    @ping + " " + @host
  end
end

class Traf
  attr_reader :iface

  def initialize(iface, tx, opts={})
    @iface = iface
    @width = opts[:width] || 60
    @buffer = opts[:buffer] || 60**3
    @backlog = Array.new(@buffer)
    @tx = tx
    @field = tx ? 6 : 5
  end

  def run
    loop {
      IO.popen(["sar", "-n", "DEV", "1", :err=>[:child, :out]]) { |rd,wr|
        while line = rd.gets
          fields = line.split
          if fields[2] == @iface
            @backlog.shift
            @backlog << fields[@field].to_f
          end
        end
      }
    }
  end
  
  SYMBOLS = "\u2581\u2581\u2582\u2583\u2584\u2585\u2586\u2587\u2587"
  COLORS = %W{\e[1;32m \e[1;32m \e[0;32m \e[1;33m \e[0;33m \e[0;31m \e[1;31m \e[1;32m}.reverse
  OFFSETS = [   0.9,   2,    50,    100,  1_000,  10_000,  20_000, 70_000   ]

  def avg(v)
    v.empty? ? 0 : v.inject(:+) / v.size
  end

  def stat(v)
    v2 = v.compact.find_all{|x| x!=:loss && x!=:down}
    [v2.min || 0.0, avg(v2), v2.max || 0.0]
  end

  def to_s(res=1)
    v = aggreg(res)
    min, avg, max = stat(v)

    line = v.last(@width).map { |d|
      if d == :loss
        "\e[1;30mx"
      elsif d == :down
        "\e[1;30mD"
      elsif d
        c = COLORS[OFFSETS.index { |cc| d < cc } || COLORS.size-1]
        
        if max == min
          c + SYMBOLS[SYMBOLS.size/2]
        else
          c + SYMBOLS[(((d-min) / (max-min))*SYMBOLS.size - 0.5).to_i]
        end
      else
        "\e[0;37m\u00B7"
      end
    }.join
  
    "\e[0;37m%s%s%s %s\e[0;37m" % [fmt(min), fmt(avg), fmt(max), line]
  end

  def fmt(kb)
    if kb >= 1000
      "%5.1fM" % (kb/1024)
    else
      "%5.1fk" % kb
    end
  end

  def aggreg(res)
    @backlog.last(res*@width).each_slice(res).map { |s| char s }
  end

  def char(ary)
    if ary.count(:down) == ary.size
      :down 
    elsif ary.size > 0 && ary.count(:loss).to_f / ary.compact.size >= 0.05
      :loss
    elsif ary.count(nil) == ary.size
      nil
    else
      avg(ary.grep(Numeric))
    end
  end

  def desc
    "#{iface} #{@tx ? "tx" : "rx"}"
  end
end

hosts = []

ping = "ping"
ARGV.each { |h|
  case h
  when "-4"
    ping = "ping"
  when "-6"
    ping = "ping6"
  when /^traf:/
    hosts << Traf.new($', true)
    hosts << Traf.new($', false)
  else
    hosts << Ping.new(h, :ping => ping)    
  end
}

hosts.each { |h| Thread.new { h.run } }

begin
  print "\e[H\e[2J\e[?25l"

hostname = `hostname`.strip

def puts(*s)
  $stdout.print("\e[K")
  $stdout.puts(*s)
end

loop {
  print "\e[H"
  puts "\e[1;37m%s" % "ncping 0.1 on #{hostname} - #{Time.now}".center(80)
  puts

  hosts.each { |h|
    puts "\e[1;37m%s" % h.desc
    puts("\e[1K" + h.to_s)
    puts h.to_s(60)
    puts h.to_s(60*60)
    # puts
  }
  print "\e[J"
  sleep 1
}

rescue Interrupt
  exit
ensure
  puts "\e[0;37m\e[?25h"
end