exports.utf8 = exports['utf-8'] = {
  encode: function(data){
    return isBinary(data)
      ? data
      : String(data);
  },
  decode: identity,
  buffer: false,
  type: 'utf8'
};

exports.json = {
  encode: JSON.stringify,
  decode: JSON.parse,
  buffer: false,
  type: 'json'
};

exports.binary = {
  encode: function(data){
    return isBinary(data)
      ? data
      : new Buffer(data);      
  },
  decode: identity,
  buffer: true,
  type: 'binary'
};

exports.none = {
  encode: identity,
  decode: identity,
  buffer: false,
  type: 'id'
};

exports.id = exports.none;

var bufferEncodings = [
  'hex',
  'ascii',
  'base64',
  'ucs2',
  'ucs-2',
  'utf16le',
  'utf-16le'
];

bufferEncodings.forEach(function(type){
  exports[type] = {
    encode: function(data){
      return isBinary(data)
        ? data
        : new Buffer(data, type);
    },
    decode: function(buffer){
      return buffer.toString(type);
    },
    buffer: true,
    type: type
  };
});

function identity(value){
  return value;
}

function isBinary(data){
  return data === undefined
    || data === null
    || Buffer.isBuffer(data);
}
