# coding: utf-8
require "base64"
require 'rubygems'
require 'redis'
require 'digest/md5'
require 'open-uri'

options = {
  :timeout     => 120,
  :thread_safe => true
}

host = ENV["REDIS_HOST"] || 'localhost'
port = ENV["REDIS_PORT"] || 6379
db   = ENV["REDIS_DB"]   || 1

options.merge!({ :host => host, :port => port, :db => db })
redis = Redis.connect(options)

@iterations = [1]
10.times   { |i| @iterations << (i+1)*10  }
100.times { |i| @iterations << (i+1)*100 }
@iterations.uniq!

class WebPage

  attr_reader :redis, :ttl

  def initialize(redis, ttl = 900)
    @redis = redis
    @ttl = ttl
  end

  def read(url)
    unless d = get(url)
      d = open(url).read
      set(url, d)
    end
    d
  end

  private

  def set(url, page)
    k = key(url)
    @redis.set(k, page)
    @redis.expire(k, @ttl)
  end

  def get(url)
    @redis.get(key(url))
  end

  def key(url)
    "webpage:#{Digest::MD5.hexdigest(url)}"
  end
end

class ResultStorer
  def self.save(time, iterations, filename)
    File.open(filename, 'a') {|f| f.write("#{time} - #{iterations}\n") }
  end
end

class Benchmark
  def self.run(filename, name)
    time_before = Time.now
    iterations = yield
    time_after = Time.now
    time_taken = time_after-time_before
    ResultStorer.save(time_taken, iterations, filename)
    print "#{name}: time: #{time_taken}\n"
  end
end

wp = WebPage.new(redis)

10.times do |attemp|
  @iterations.each do |i|

    time = Time.now.to_i

    Benchmark.run("not-cached-#{attemp}.txt", "Not cached: #{i}") do
      i.times { |j| open("http://127.0.0.1/phpmyadmin/?req=#{i}&time=#{time}") }
      i
    end

    Benchmark.run("cached-#{attemp}.txt", "Cached: #{i}") do
      i.times { |j| wp.read("http://127.0.0.1/phpmyadmin/?req=#{i}&time=#{time}") }
      i
    end

  end
end