class Typhoeus::ParamProcessor

def process_value(current_value, options)
  result = options[:result]
  new_key = options[:new_key]
  case current_value
  when Hash
    traverse_params_hash(current_value, result, new_key)
  when Array
    current_value.each do |v|
      result[:params] << [new_key, v.to_s]
    end
  when File, Tempfile
    filename = File.basename(current_value.path)
    types = MIME::Types.type_for(filename)
    result[:files] << [
      new_key,
      filename,
      types.empty? ? 'application/octet-stream' : types[0].to_s,
      File.expand_path(current_value.path)
    ]
  else
    result[:params] << [new_key, current_value.to_s]
  end
end

def traverse_params_hash(hash, result = nil, current_key = nil)
  result ||= { :files => [], :params => [] }
  hash.keys.sort { |a, b| a.to_s <=> b.to_s }.collect do |key|
    new_key = (current_key ? "#{current_key}[#{key}]" : key).to_s
    current_value = hash[key]
    process_value current_value, :result => result, :new_key => new_key
  end
  result
end