class ActionDispatch::ParamsParser

def call(env)
  if params = parse_formatted_parameters(env)
    env["action_dispatch.request.request_parameters"] = params
  end
  @app.call(env)
end

def content_type_from_legacy_post_data_format_header(env)
  if x_post_format = env['HTTP_X_POST_DATA_FORMAT']
    case x_post_format.to_s.downcase
    when 'yaml' then return Mime::YAML
    when 'xml'  then return Mime::XML
    end
  end
  nil
end

def initialize(app, parsers = {})
  @app, @parsers = app, DEFAULT_PARSERS.merge(parsers)
end

def logger(env)
  env['action_dispatch.logger'] || Logger.new($stderr)
end

def parse_formatted_parameters(env)
  request = Request.new(env)
  return false if request.content_length.zero?
  mime_type = content_type_from_legacy_post_data_format_header(env) ||
    request.content_mime_type
  strategy = @parsers[mime_type]
  return false unless strategy
  case strategy
  when Proc
    strategy.call(request.raw_post)
  when :xml_simple, :xml_node
    data = Hash.from_xml(request.body.read) || {}
    request.body.rewind if request.body.respond_to?(:rewind)
    data.with_indifferent_access
  when :yaml
    YAML.load(request.raw_post)
  when :json
    data = ActiveSupport::JSON.decode(request.body)
    request.body.rewind if request.body.respond_to?(:rewind)
    data = {:_json => data} unless data.is_a?(Hash)
    data.with_indifferent_access
  else
    false
  end
rescue Exception => e # YAML, XML or Ruby code block errors
  logger(env).debug "Error occurred while parsing request parameters.\nContents:\n\n#{request.raw_post}"
  raise e
end