module Ethon::Easies::Util

def self.escape_zero_byte(value)
  return value unless value.to_s.include?(0.chr)
  value.to_s.gsub(0.chr, '\\\0')
end

def build_query_pairs(hash)
  pairs = []
  recursive = Proc.new do |h, prefix|
    h.each_pair do |k,v|
      key = prefix == '' ? k : "#{prefix}[#{k}]"
      case v
      when Hash
        recursive.call(v, key)
      when Array
        v.each { |x| pairs << [key, x]  }
      when File, Tempfile
        pairs << [Util.escape_zero_byte(key), file_info(v)]
      else
        pairs << [Util.escape_zero_byte(key), Util.escape_zero_byte(v)]
      end
    end
  end
  recursive.call(hash, '')
  pairs
end

def file_info(file)
  filename = File.basename(file.path)
  types = MIME::Types.type_for(filename)
  [
    filename,
    types.empty? ? 'application/octet-stream' : types[0].to_s,
    File.expand_path(file.path)
  ]
end