config.ru

require "rubygems"
require "sinatra/base"
require "padrino"

class Foo < Sinatra::Base
  get("/bar") { 
    "Hello world!"
  }
end

class Bar < Padrino::Application
  disable :debug
  get("/bar") { 
    "Hello world!"
  }
end

module Rack
  class Mountable
    attr_reader :app, :path, :host, :port, :name
    
    def initialize(app)
      @app = app
    end
    
    def to(path)
      @path = "^/#{path}(.*)".gsub(%r{^\^//}, "^/")
      return self
    end
    
    def as(name)
      @name = name
      return self
    end
    
    def bind(url)
      @host, @port = url.split(":")
      @host = @host.gsub('*', '.*').gsub('.', '\.')
      return self
    end
  end
  
  class Mounter
    def initialize(&block)
      @mountables = [] 
      instance_eval(&block) if block_given?
    end
    
    def mountables
      @mountables
    end
    
    def mount(app)
      @mountables << (mnt = Mountable.new(app)) and return mnt
    end
    
    def call(env)
      path, script, host, port, name = env.values_at \
        'PATH_INFO', 'SCRIPT_NAME', 'HTTP_HOST', 'SERVER_PORT', 'SERVER_NAME'
      threads = []

      @mountables.each do |mnt|
        next if mnt.host && (!host.match(mnt.host) || !name.match(mnt.host))
        next if mnt.port && (mnt.port.to_i != port.to_i)
        next if mnt.path.nil? || !(match = path.match(mnt.path))
        
        env.merge!(
          'SCRIPT_NAME' => script + match[0], 
          'PATH_INFO'   => "/#{match[-1]}".gsub(%r{^//}, "/")
        )

        return mnt.app.call(env)
      end
      
      [404, {"Content-Type" => "text/plain", "X-Cascade" => "pass"}, ["Not Found: #{path}"]]
    end
  end
end

module Padrino
  #class Mounter < Rack::Mounter
  #end
  
  class << self
    def builder
      @builder ||= Rack::Builder.new { run Rack::Mounter.new }
    end
    alias :application :builder
    
    def mount(app)
      builder.to_app.mount(app)
    end
  end
end

Padrino.mount(Foo).bind("localhost").to("/")
Padrino.mount(Bar).bind("*.example.com").to("/foo")
Padrino.mount(Foo).bind("example.com").to("/")

run Padrino.builder