require 'rubygems'
require 'rack'

module ::Rack
    class TryStatic < Static
        def initialize(app, options)
            super
            @try = ([''] + Array(options.delete(:try)) + [''])
        end

        def call(env)
            @next = 0
            while @next < @try.size && 404 == (resp = super(try_next(env)))[0] 
                @next += 1
            end
            404 == resp[0] ? @app.call : resp
        end

        private
        def try_next(env)
            env.merge('PATH_INFO' => env['PATH_INFO'] + @try[@next])
        end

    end
end