#!/usr/bin/env ruby
require 'net/http'

def law_of_cosine(lat1, long1, lat2, long2)
  Math.acos( (Math.sin(lat1)*Math.sin(lat2)) + (Math.cos(lat1)*Math.cos(lat2)) * Math.cos((long1-long2).abs))
end

def great_circle_distance(rads)
  6371.01 * rads
end

santas_distance = 0
d = { "firstlat" => 0, "firstlng" => 0, "secondlat" => 0, "secondlng" => 0}
url = URI.parse('http://www.noradsanta.org/js/data.js')
req = Net::HTTP::Get.new(url.path)
resp = Net::HTTP.start(url.host, url.port) {|http|
  http.request(req)
}

resp.body.each do |line|
  line.chomp
  puts line
  if line.include? "lat" and d['firstlat'] == 0
    arr = line.map {|x| x[/[0-9]*\.[0-9]+|[0-9]+/]}
    d['firstlat'] = arr[0].to_i
  elsif line.include? "lat"
    arr = line.map {|x| x[/[0-9]*\.[0-9]+|[0-9]+/]}
    d['secondlat'] = arr[0].to_i
  end
  if line.include? "lng" and d['firstlng'] == 0
    arr = line.map {|x| x[/[0-9]*\.[0-9]+|[0-9]+/]}
    d['firstlng'] = arr[0].to_i
  elsif line.include? "lng"
    arr = line.map {|x| x[/[0-9]*\.[0-9]+|[0-9]+/]}
    d['secondlng'] = arr[0].to_i
  end
  if d['firstlat'] != 0 and d['secondlat'] != 0 and d['firstlng'] != 0 and d['secondlng'] != 0
    rads = law_of_cosine(d['firstlat'], d['firstlng'], d['secondlat'], d['secondlng'])
    santas_distance += great_circle_distance(rads)
    d['firstlat'] = 0
    d['firstlng'] = 0
    d['secondlat'] = 0
    d['secondlng'] = 0
  end
end
puts santas_distance