module BigBench
  
  # Holds the actual benchmark methods. A benchmark is a sequence of requests to the same server, but to different paths.
  # A testrun can consist of multiple benchmarks like this:
  # 
  #    benchmark "default website pages" => "http://localhost:3000" do
  #       get "/"
  #       get "/blog"
  #       get "/imprint"
  #       get "/admin", :basic_auth => ['admin', 'secret']
  #    end
  #
  #    benchmark "login and logout" => "http://localhost:3000" do
  #       post "/login", :params => { :name => "test@user.com", :password => "secret" }
  #       post "/logout", :params => { :name => "test@user.com" }
  #    end
  #
  # Those benchmarks automatically get added to the modules benchmark array and can be retrieved with the BigBench#benchmarks method.
  module Benchmark
  
    @benchmarks = []
  
    class Benchmark
    
      attr_accessor :name
      attr_accessor :uri
      attr_accessor :users
      attr_accessor :duration
      attr_accessor :fragments
      attr_accessor :tracker
      attr_accessor :start
      attr_accessor :is_running
      attr_accessor :runs
      
      # Initizalizes a new benchmark
      def initialize(name, url, options, &block)
        @name, @uri, @tracker, @is_running, @runs = name, URI(url), Tracker::Tracker.new, false, 0
        @users  = options[:users]   || BigBench.config.users
        @duration = options[:duration]  || BigBench.config.duration
        @fragments = BigBench::Fragment.parse(self, &block)
      end
      
      # Execute this benchmark
      def run!
        
        # Setup Timer
        timer = Thread.new{ sleep(@duration); @is_running = false }
        @start, @is_running = Time.now, true
        
        # Loop Requests
        @users.times { Looper.new(self).loop! }
        @runs += 1
      end
      
      # Returns if this benchmark is currently running
      def is_running?
        @is_running
      end
    
    end
    
    # Adds a benchmark to the <tt>BigBench</tt> module. It can later be retrieved with the <tt>all</tt> method.
    def self.add(options, &block)
      name, url  = options.select{ |key, value| true unless key.is_a?(Symbol) }.first
      benchmark = Benchmark.new(name, url, options, &block)
      @benchmarks << benchmark
      benchmark
    end
    
    # Returns all benchmarks that are registered
    def self.all
      @benchmarks
    end
    
    # Resets all benchmarks
    def self.reset!
      @benchmarks = []
    end
    
    # Returns the longest duration of all benchmarks
    def self.max_duration
      all.map{ |benchmark| benchmark.duration }.max
    end
    
  end
  
  # Add a benchmark like this:
  # 
  #    benchmark "default website pages" => "http://localhost:3000" do
  #       get "/"
  #       get "/blog"
  #       get "/imprint"
  #       get "/admin", :basic_auth => ['admin', 'secret']
  #    end
  #
  #    benchmark "login and logout" => "http://localhost:3000" do
  #       post "/login",  :params => { :name => "test@user.com", :password => "secret" }
  #       post "/logout", :params => { :name => "test@user.com" }
  #    end
  #
  def self.benchmark(options)
    return unless block_given?
    Benchmark.add(options, &Proc.new)
  end
  
  # List all available benchmarks
  def self.benchmarks
    Benchmark.all
  end
  
  # Returns the duration of all benchmarks - ergo the duration of the longest one
  def self.duration
    Benchmark.max_duration
  end
  
end