module Qeweney

def self.rack(&block)
  proc do |env|
    adapter = RackRequestAdapter.new(env)
    req = Request.new(adapter.request_headers, adapter)
    block.(req)
    adapter.rack_response
  end
end

def self.rack_env_from_request(request)
  Hash.new do |h, k|
    h[k] = rack_env_value_from_request(request, k)
  end
end

def self.rack_env_value_from_request(request, key)
  case key
  when 'REQUEST_METHOD' then request.method.upcase
  when 'PATH_INFO'      then request.path
  when 'QUERY_STRING'   then request.query_string || ''
  when 'SERVER_NAME'    then request.headers['host']
  when 'rack.input'     then InputStream.new(request)
  when HTTP_HEADER_RE   then request.headers[$1.gsub('_', '-').downcase]
  else                       RACK_ENV[key]
  end
end

def self.route(&block)
  ->(r) { r.route(&block) }
end