class Rack::RubyProf

def call(env)
  request = Rack::Request.new(env)
  if should_profile?(request.path)
    begin
      result = nil
      profile = ::RubyProf::Profile.profile(**profiling_options) do
        result = @app.call(env)
      end
      if @merge_fibers
        profile.merge!
      end
      path = request.path.gsub('/', '-')
      path.slice!(0)
      print(profile, path)
      result
    end
  else
    @app.call(env)
  end
end

def initialize(app, path: Dir.tmpdir, printers: nil, skip_paths: nil,
               only_paths: nil, merge_fibers: false,
               measure_mode: ::RubyProf::WALL_TIME, track_allocations: false,
               exclude_common: false, ignore_existing_threads: false,
               request_thread_only: false, min_percent: 1,
               sort_method: :total_time)
  @app = app
  @tmpdir = path.to_s
  FileUtils.mkdir_p(@tmpdir)
  @printer_klasses = printers || {::RubyProf::FlatPrinter => 'flat.txt',
                                  ::RubyProf::GraphPrinter => 'graph.txt',
                                  ::RubyProf::GraphHtmlPrinter => 'graph.html',
                                  ::RubyProf::CallStackPrinter => 'call_stack.html'}
  @skip_paths = skip_paths || [%r{^/assets}, %r{\.(css|js|png|jpeg|jpg|gif)$}]
  @only_paths = only_paths
  @merge_fibers = merge_fibers
  @measure_mode = measure_mode
  @track_allocations = track_allocations
  @exclude_common = exclude_common
  @ignore_existing_threads = ignore_existing_threads
  @request_thread_only = request_thread_only
  @min_percent = min_percent
  @sort_method = sort_method
end

def paths_match?(path, paths)
  paths.any? { |skip_path| skip_path =~ path }
end

def print(profile, path)
  @printer_klasses.each do |printer_klass, base_name|
    printer = printer_klass.new(profile)
    if base_name.respond_to?(:call)
      base_name = base_name.call
    end
    if printer_klass == ::RubyProf::MultiPrinter
      printer.print(profile: "#{path}-#{base_name}", **print_options)
    elsif printer_klass == ::RubyProf::CallTreePrinter
      printer.print(profile: "#{path}-#{base_name}", **print_options)
    else
      file_name = ::File.join(@tmpdir, "#{path}-#{base_name}")
      ::File.open(file_name, 'wb') do |file|
        printer.print(file, **print_options)
      end
    end
  end
end

def print_options
  {min_percent: @min_percent, sort_method: @sort_method}
end

def profiling_options
  result = {}
  result[:measure_mode] = @measure_mode
  result[:track_allocations] = @track_allocations
  result[:exclude_common] = @exclude_common
  if @ignore_existing_threads
    result[:exclude_threads] = Thread.list.select {|thread| thread != Thread.current}
  end
  if @request_thread_only
    result[:include_threads] = [Thread.current]
  end
  result
end

def should_profile?(path)
  return false if paths_match?(path, @skip_paths)
  @only_paths ? paths_match?(path, @only_paths) : true
end