@serverless-stack/nextjs-lambda/dist/default-handler/standard/index-253b0c60.js

Provides handlers that can be used in CloudFront Lambda@Edge to deploy next.js applications to the edge

'use strict';

var defaultHandler = require('./default-handler-b3f3c1c7.js');
var buffer = require('buffer');
var Stream = require('stream');
var util = require('util');
var crypto = require('crypto');

function _interopDefaultLegacy (e) { return e && typeof e === 'object' && 'default' in e ? e : { 'default': e }; }

var buffer__default = /*#__PURE__*/_interopDefaultLegacy(buffer);
var Stream__default = /*#__PURE__*/_interopDefaultLegacy(Stream);
var util__default = /*#__PURE__*/_interopDefaultLegacy(util);
var crypto__default = /*#__PURE__*/_interopDefaultLegacy(crypto);

/*! safe-buffer. MIT License. Feross Aboukhadijeh <https://feross.org/opensource> */

var safeBuffer = defaultHandler.createCommonjsModule(function (module, exports) {
/* eslint-disable node/no-deprecated-api */

var Buffer = buffer__default['default'].Buffer;

// alternative to using Object.keys for old browsers
function copyProps (src, dst) {
  for (var key in src) {
    dst[key] = src[key];
  }
}
if (Buffer.from && Buffer.alloc && Buffer.allocUnsafe && Buffer.allocUnsafeSlow) {
  module.exports = buffer__default['default'];
} else {
  // Copy properties from require('buffer')
  copyProps(buffer__default['default'], exports);
  exports.Buffer = SafeBuffer;
}

function SafeBuffer (arg, encodingOrOffset, length) {
  return Buffer(arg, encodingOrOffset, length)
}

SafeBuffer.prototype = Object.create(Buffer.prototype);

// Copy static methods from Buffer
copyProps(Buffer, SafeBuffer);

SafeBuffer.from = function (arg, encodingOrOffset, length) {
  if (typeof arg === 'number') {
    throw new TypeError('Argument must not be a number')
  }
  return Buffer(arg, encodingOrOffset, length)
};

SafeBuffer.alloc = function (size, fill, encoding) {
  if (typeof size !== 'number') {
    throw new TypeError('Argument must be a number')
  }
  var buf = Buffer(size);
  if (fill !== undefined) {
    if (typeof encoding === 'string') {
      buf.fill(fill, encoding);
    } else {
      buf.fill(fill);
    }
  } else {
    buf.fill(0);
  }
  return buf
};

SafeBuffer.allocUnsafe = function (size) {
  if (typeof size !== 'number') {
    throw new TypeError('Argument must be a number')
  }
  return Buffer(size)
};

SafeBuffer.allocUnsafeSlow = function (size) {
  if (typeof size !== 'number') {
    throw new TypeError('Argument must be a number')
  }
  return buffer__default['default'].SlowBuffer(size)
};
});

/*global module, process*/

var Buffer$7 = safeBuffer.Buffer;



function DataStream(data) {
  this.buffer = null;
  this.writable = true;
  this.readable = true;

  // No input
  if (!data) {
    this.buffer = Buffer$7.alloc(0);
    return this;
  }

  // Stream
  if (typeof data.pipe === 'function') {
    this.buffer = Buffer$7.alloc(0);
    data.pipe(this);
    return this;
  }

  // Buffer or String
  // or Object (assumedly a passworded key)
  if (data.length || typeof data === 'object') {
    this.buffer = data;
    this.writable = false;
    process.nextTick(function () {
      this.emit('end', data);
      this.readable = false;
      this.emit('close');
    }.bind(this));
    return this;
  }

  throw new TypeError('Unexpected data type ('+ typeof data + ')');
}
util__default['default'].inherits(DataStream, Stream__default['default']);

DataStream.prototype.write = function write(data) {
  this.buffer = Buffer$7.concat([this.buffer, Buffer$7.from(data)]);
  this.emit('data', data);
};

DataStream.prototype.end = function end(data) {
  if (data)
    this.write(data);
  this.emit('end', data);
  this.emit('close');
  this.writable = false;
  this.readable = false;
};

var dataStream = DataStream;

/*jshint node:true */
var Buffer$6 = buffer__default['default'].Buffer; // browserify
var SlowBuffer = buffer__default['default'].SlowBuffer;

var bufferEqualConstantTime = bufferEq;

function bufferEq(a, b) {

  // shortcutting on type is necessary for correctness
  if (!Buffer$6.isBuffer(a) || !Buffer$6.isBuffer(b)) {
    return false;
  }

  // buffer sizes should be well-known information, so despite this
  // shortcutting, it doesn't leak any information about the *contents* of the
  // buffers.
  if (a.length !== b.length) {
    return false;
  }

  var c = 0;
  for (var i = 0; i < a.length; i++) {
    /*jshint bitwise:false */
    c |= a[i] ^ b[i]; // XOR
  }
  return c === 0;
}

bufferEq.install = function() {
  Buffer$6.prototype.equal = SlowBuffer.prototype.equal = function equal(that) {
    return bufferEq(this, that);
  };
};

var origBufEqual = Buffer$6.prototype.equal;
var origSlowBufEqual = SlowBuffer.prototype.equal;
bufferEq.restore = function() {
  Buffer$6.prototype.equal = origBufEqual;
  SlowBuffer.prototype.equal = origSlowBufEqual;
};

function getParamSize(keySize) {
	var result = ((keySize / 8) | 0) + (keySize % 8 === 0 ? 0 : 1);
	return result;
}

var paramBytesForAlg = {
	ES256: getParamSize(256),
	ES384: getParamSize(384),
	ES512: getParamSize(521)
};

function getParamBytesForAlg(alg) {
	var paramBytes = paramBytesForAlg[alg];
	if (paramBytes) {
		return paramBytes;
	}

	throw new Error('Unknown algorithm "' + alg + '"');
}

var paramBytesForAlg_1 = getParamBytesForAlg;

var Buffer$5 = safeBuffer.Buffer;



var MAX_OCTET = 0x80,
	CLASS_UNIVERSAL = 0,
	PRIMITIVE_BIT = 0x20,
	TAG_SEQ = 0x10,
	TAG_INT = 0x02,
	ENCODED_TAG_SEQ = (TAG_SEQ | PRIMITIVE_BIT) | (CLASS_UNIVERSAL << 6),
	ENCODED_TAG_INT = TAG_INT | (CLASS_UNIVERSAL << 6);

function base64Url(base64) {
	return base64
		.replace(/=/g, '')
		.replace(/\+/g, '-')
		.replace(/\//g, '_');
}

function signatureAsBuffer(signature) {
	if (Buffer$5.isBuffer(signature)) {
		return signature;
	} else if ('string' === typeof signature) {
		return Buffer$5.from(signature, 'base64');
	}

	throw new TypeError('ECDSA signature must be a Base64 string or a Buffer');
}

function derToJose(signature, alg) {
	signature = signatureAsBuffer(signature);
	var paramBytes = paramBytesForAlg_1(alg);

	// the DER encoded param should at most be the param size, plus a padding
	// zero, since due to being a signed integer
	var maxEncodedParamLength = paramBytes + 1;

	var inputLength = signature.length;

	var offset = 0;
	if (signature[offset++] !== ENCODED_TAG_SEQ) {
		throw new Error('Could not find expected "seq"');
	}

	var seqLength = signature[offset++];
	if (seqLength === (MAX_OCTET | 1)) {
		seqLength = signature[offset++];
	}

	if (inputLength - offset < seqLength) {
		throw new Error('"seq" specified length of "' + seqLength + '", only "' + (inputLength - offset) + '" remaining');
	}

	if (signature[offset++] !== ENCODED_TAG_INT) {
		throw new Error('Could not find expected "int" for "r"');
	}

	var rLength = signature[offset++];

	if (inputLength - offset - 2 < rLength) {
		throw new Error('"r" specified length of "' + rLength + '", only "' + (inputLength - offset - 2) + '" available');
	}

	if (maxEncodedParamLength < rLength) {
		throw new Error('"r" specified length of "' + rLength + '", max of "' + maxEncodedParamLength + '" is acceptable');
	}

	var rOffset = offset;
	offset += rLength;

	if (signature[offset++] !== ENCODED_TAG_INT) {
		throw new Error('Could not find expected "int" for "s"');
	}

	var sLength = signature[offset++];

	if (inputLength - offset !== sLength) {
		throw new Error('"s" specified length of "' + sLength + '", expected "' + (inputLength - offset) + '"');
	}

	if (maxEncodedParamLength < sLength) {
		throw new Error('"s" specified length of "' + sLength + '", max of "' + maxEncodedParamLength + '" is acceptable');
	}

	var sOffset = offset;
	offset += sLength;

	if (offset !== inputLength) {
		throw new Error('Expected to consume entire buffer, but "' + (inputLength - offset) + '" bytes remain');
	}

	var rPadding = paramBytes - rLength,
		sPadding = paramBytes - sLength;

	var dst = Buffer$5.allocUnsafe(rPadding + rLength + sPadding + sLength);

	for (offset = 0; offset < rPadding; ++offset) {
		dst[offset] = 0;
	}
	signature.copy(dst, offset, rOffset + Math.max(-rPadding, 0), rOffset + rLength);

	offset = paramBytes;

	for (var o = offset; offset < o + sPadding; ++offset) {
		dst[offset] = 0;
	}
	signature.copy(dst, offset, sOffset + Math.max(-sPadding, 0), sOffset + sLength);

	dst = dst.toString('base64');
	dst = base64Url(dst);

	return dst;
}

function countPadding(buf, start, stop) {
	var padding = 0;
	while (start + padding < stop && buf[start + padding] === 0) {
		++padding;
	}

	var needsSign = buf[start + padding] >= MAX_OCTET;
	if (needsSign) {
		--padding;
	}

	return padding;
}

function joseToDer(signature, alg) {
	signature = signatureAsBuffer(signature);
	var paramBytes = paramBytesForAlg_1(alg);

	var signatureBytes = signature.length;
	if (signatureBytes !== paramBytes * 2) {
		throw new TypeError('"' + alg + '" signatures must be "' + paramBytes * 2 + '" bytes, saw "' + signatureBytes + '"');
	}

	var rPadding = countPadding(signature, 0, paramBytes);
	var sPadding = countPadding(signature, paramBytes, signature.length);
	var rLength = paramBytes - rPadding;
	var sLength = paramBytes - sPadding;

	var rsBytes = 1 + 1 + rLength + 1 + 1 + sLength;

	var shortLength = rsBytes < MAX_OCTET;

	var dst = Buffer$5.allocUnsafe((shortLength ? 2 : 3) + rsBytes);

	var offset = 0;
	dst[offset++] = ENCODED_TAG_SEQ;
	if (shortLength) {
		// Bit 8 has value "0"
		// bits 7-1 give the length.
		dst[offset++] = rsBytes;
	} else {
		// Bit 8 of first octet has value "1"
		// bits 7-1 give the number of additional length octets.
		dst[offset++] = MAX_OCTET	| 1;
		// length, base 256
		dst[offset++] = rsBytes & 0xff;
	}
	dst[offset++] = ENCODED_TAG_INT;
	dst[offset++] = rLength;
	if (rPadding < 0) {
		dst[offset++] = 0;
		offset += signature.copy(dst, offset, 0, paramBytes);
	} else {
		offset += signature.copy(dst, offset, rPadding, paramBytes);
	}
	dst[offset++] = ENCODED_TAG_INT;
	dst[offset++] = sLength;
	if (sPadding < 0) {
		dst[offset++] = 0;
		signature.copy(dst, offset, paramBytes);
	} else {
		signature.copy(dst, offset, paramBytes + sPadding);
	}

	return dst;
}

var ecdsaSigFormatter = {
	derToJose: derToJose,
	joseToDer: joseToDer
};

var Buffer$4 = safeBuffer.Buffer;




var MSG_INVALID_ALGORITHM = '"%s" is not a valid algorithm.\n  Supported algorithms are:\n  "HS256", "HS384", "HS512", "RS256", "RS384", "RS512", "PS256", "PS384", "PS512", "ES256", "ES384", "ES512" and "none".';
var MSG_INVALID_SECRET = 'secret must be a string or buffer';
var MSG_INVALID_VERIFIER_KEY = 'key must be a string or a buffer';
var MSG_INVALID_SIGNER_KEY = 'key must be a string, a buffer or an object';

var supportsKeyObjects = typeof crypto__default['default'].createPublicKey === 'function';
if (supportsKeyObjects) {
  MSG_INVALID_VERIFIER_KEY += ' or a KeyObject';
  MSG_INVALID_SECRET += 'or a KeyObject';
}

function checkIsPublicKey(key) {
  if (Buffer$4.isBuffer(key)) {
    return;
  }

  if (typeof key === 'string') {
    return;
  }

  if (!supportsKeyObjects) {
    throw typeError(MSG_INVALID_VERIFIER_KEY);
  }

  if (typeof key !== 'object') {
    throw typeError(MSG_INVALID_VERIFIER_KEY);
  }

  if (typeof key.type !== 'string') {
    throw typeError(MSG_INVALID_VERIFIER_KEY);
  }

  if (typeof key.asymmetricKeyType !== 'string') {
    throw typeError(MSG_INVALID_VERIFIER_KEY);
  }

  if (typeof key.export !== 'function') {
    throw typeError(MSG_INVALID_VERIFIER_KEY);
  }
}
function checkIsPrivateKey(key) {
  if (Buffer$4.isBuffer(key)) {
    return;
  }

  if (typeof key === 'string') {
    return;
  }

  if (typeof key === 'object') {
    return;
  }

  throw typeError(MSG_INVALID_SIGNER_KEY);
}
function checkIsSecretKey(key) {
  if (Buffer$4.isBuffer(key)) {
    return;
  }

  if (typeof key === 'string') {
    return key;
  }

  if (!supportsKeyObjects) {
    throw typeError(MSG_INVALID_SECRET);
  }

  if (typeof key !== 'object') {
    throw typeError(MSG_INVALID_SECRET);
  }

  if (key.type !== 'secret') {
    throw typeError(MSG_INVALID_SECRET);
  }

  if (typeof key.export !== 'function') {
    throw typeError(MSG_INVALID_SECRET);
  }
}

function fromBase64(base64) {
  return base64
    .replace(/=/g, '')
    .replace(/\+/g, '-')
    .replace(/\//g, '_');
}

function toBase64(base64url) {
  base64url = base64url.toString();

  var padding = 4 - base64url.length % 4;
  if (padding !== 4) {
    for (var i = 0; i < padding; ++i) {
      base64url += '=';
    }
  }

  return base64url
    .replace(/\-/g, '+')
    .replace(/_/g, '/');
}

function typeError(template) {
  var args = [].slice.call(arguments, 1);
  var errMsg = util__default['default'].format.bind(util__default['default'], template).apply(null, args);
  return new TypeError(errMsg);
}

function bufferOrString(obj) {
  return Buffer$4.isBuffer(obj) || typeof obj === 'string';
}

function normalizeInput(thing) {
  if (!bufferOrString(thing))
    thing = JSON.stringify(thing);
  return thing;
}

function createHmacSigner(bits) {
  return function sign(thing, secret) {
    checkIsSecretKey(secret);
    thing = normalizeInput(thing);
    var hmac = crypto__default['default'].createHmac('sha' + bits, secret);
    var sig = (hmac.update(thing), hmac.digest('base64'));
    return fromBase64(sig);
  }
}

function createHmacVerifier(bits) {
  return function verify(thing, signature, secret) {
    var computedSig = createHmacSigner(bits)(thing, secret);
    return bufferEqualConstantTime(Buffer$4.from(signature), Buffer$4.from(computedSig));
  }
}

function createKeySigner(bits) {
 return function sign(thing, privateKey) {
    checkIsPrivateKey(privateKey);
    thing = normalizeInput(thing);
    // Even though we are specifying "RSA" here, this works with ECDSA
    // keys as well.
    var signer = crypto__default['default'].createSign('RSA-SHA' + bits);
    var sig = (signer.update(thing), signer.sign(privateKey, 'base64'));
    return fromBase64(sig);
  }
}

function createKeyVerifier(bits) {
  return function verify(thing, signature, publicKey) {
    checkIsPublicKey(publicKey);
    thing = normalizeInput(thing);
    signature = toBase64(signature);
    var verifier = crypto__default['default'].createVerify('RSA-SHA' + bits);
    verifier.update(thing);
    return verifier.verify(publicKey, signature, 'base64');
  }
}

function createPSSKeySigner(bits) {
  return function sign(thing, privateKey) {
    checkIsPrivateKey(privateKey);
    thing = normalizeInput(thing);
    var signer = crypto__default['default'].createSign('RSA-SHA' + bits);
    var sig = (signer.update(thing), signer.sign({
      key: privateKey,
      padding: crypto__default['default'].constants.RSA_PKCS1_PSS_PADDING,
      saltLength: crypto__default['default'].constants.RSA_PSS_SALTLEN_DIGEST
    }, 'base64'));
    return fromBase64(sig);
  }
}

function createPSSKeyVerifier(bits) {
  return function verify(thing, signature, publicKey) {
    checkIsPublicKey(publicKey);
    thing = normalizeInput(thing);
    signature = toBase64(signature);
    var verifier = crypto__default['default'].createVerify('RSA-SHA' + bits);
    verifier.update(thing);
    return verifier.verify({
      key: publicKey,
      padding: crypto__default['default'].constants.RSA_PKCS1_PSS_PADDING,
      saltLength: crypto__default['default'].constants.RSA_PSS_SALTLEN_DIGEST
    }, signature, 'base64');
  }
}

function createECDSASigner(bits) {
  var inner = createKeySigner(bits);
  return function sign() {
    var signature = inner.apply(null, arguments);
    signature = ecdsaSigFormatter.derToJose(signature, 'ES' + bits);
    return signature;
  };
}

function createECDSAVerifer(bits) {
  var inner = createKeyVerifier(bits);
  return function verify(thing, signature, publicKey) {
    signature = ecdsaSigFormatter.joseToDer(signature, 'ES' + bits).toString('base64');
    var result = inner(thing, signature, publicKey);
    return result;
  };
}

function createNoneSigner() {
  return function sign() {
    return '';
  }
}

function createNoneVerifier() {
  return function verify(thing, signature) {
    return signature === '';
  }
}

var jwa = function jwa(algorithm) {
  var signerFactories = {
    hs: createHmacSigner,
    rs: createKeySigner,
    ps: createPSSKeySigner,
    es: createECDSASigner,
    none: createNoneSigner,
  };
  var verifierFactories = {
    hs: createHmacVerifier,
    rs: createKeyVerifier,
    ps: createPSSKeyVerifier,
    es: createECDSAVerifer,
    none: createNoneVerifier,
  };
  var match = algorithm.match(/^(RS|PS|ES|HS)(256|384|512)$|^(none)$/i);
  if (!match)
    throw typeError(MSG_INVALID_ALGORITHM, algorithm);
  var algo = (match[1] || match[3]).toLowerCase();
  var bits = match[2];

  return {
    sign: signerFactories[algo](bits),
    verify: verifierFactories[algo](bits),
  }
};

/*global module*/

var Buffer$3 = buffer__default['default'].Buffer;

var tostring = function toString(obj) {
  if (typeof obj === 'string')
    return obj;
  if (typeof obj === 'number' || Buffer$3.isBuffer(obj))
    return obj.toString();
  return JSON.stringify(obj);
};

/*global module*/

var Buffer$2 = safeBuffer.Buffer;






function base64url(string, encoding) {
  return Buffer$2
    .from(string, encoding)
    .toString('base64')
    .replace(/=/g, '')
    .replace(/\+/g, '-')
    .replace(/\//g, '_');
}

function jwsSecuredInput(header, payload, encoding) {
  encoding = encoding || 'utf8';
  var encodedHeader = base64url(tostring(header), 'binary');
  var encodedPayload = base64url(tostring(payload), encoding);
  return util__default['default'].format('%s.%s', encodedHeader, encodedPayload);
}

function jwsSign(opts) {
  var header = opts.header;
  var payload = opts.payload;
  var secretOrKey = opts.secret || opts.privateKey;
  var encoding = opts.encoding;
  var algo = jwa(header.alg);
  var securedInput = jwsSecuredInput(header, payload, encoding);
  var signature = algo.sign(securedInput, secretOrKey);
  return util__default['default'].format('%s.%s', securedInput, signature);
}

function SignStream(opts) {
  var secret = opts.secret||opts.privateKey||opts.key;
  var secretStream = new dataStream(secret);
  this.readable = true;
  this.header = opts.header;
  this.encoding = opts.encoding;
  this.secret = this.privateKey = this.key = secretStream;
  this.payload = new dataStream(opts.payload);
  this.secret.once('close', function () {
    if (!this.payload.writable && this.readable)
      this.sign();
  }.bind(this));

  this.payload.once('close', function () {
    if (!this.secret.writable && this.readable)
      this.sign();
  }.bind(this));
}
util__default['default'].inherits(SignStream, Stream__default['default']);

SignStream.prototype.sign = function sign() {
  try {
    var signature = jwsSign({
      header: this.header,
      payload: this.payload.buffer,
      secret: this.secret.buffer,
      encoding: this.encoding
    });
    this.emit('done', signature);
    this.emit('data', signature);
    this.emit('end');
    this.readable = false;
    return signature;
  } catch (e) {
    this.readable = false;
    this.emit('error', e);
    this.emit('close');
  }
};

SignStream.sign = jwsSign;

var signStream = SignStream;

/*global module*/

var Buffer$1 = safeBuffer.Buffer;





var JWS_REGEX = /^[a-zA-Z0-9\-_]+?\.[a-zA-Z0-9\-_]+?\.([a-zA-Z0-9\-_]+)?$/;

function isObject$3(thing) {
  return Object.prototype.toString.call(thing) === '[object Object]';
}

function safeJsonParse(thing) {
  if (isObject$3(thing))
    return thing;
  try { return JSON.parse(thing); }
  catch (e) { return undefined; }
}

function headerFromJWS(jwsSig) {
  var encodedHeader = jwsSig.split('.', 1)[0];
  return safeJsonParse(Buffer$1.from(encodedHeader, 'base64').toString('binary'));
}

function securedInputFromJWS(jwsSig) {
  return jwsSig.split('.', 2).join('.');
}

function signatureFromJWS(jwsSig) {
  return jwsSig.split('.')[2];
}

function payloadFromJWS(jwsSig, encoding) {
  encoding = encoding || 'utf8';
  var payload = jwsSig.split('.')[1];
  return Buffer$1.from(payload, 'base64').toString(encoding);
}

function isValidJws(string) {
  return JWS_REGEX.test(string) && !!headerFromJWS(string);
}

function jwsVerify(jwsSig, algorithm, secretOrKey) {
  if (!algorithm) {
    var err = new Error("Missing algorithm parameter for jws.verify");
    err.code = "MISSING_ALGORITHM";
    throw err;
  }
  jwsSig = tostring(jwsSig);
  var signature = signatureFromJWS(jwsSig);
  var securedInput = securedInputFromJWS(jwsSig);
  var algo = jwa(algorithm);
  return algo.verify(securedInput, signature, secretOrKey);
}

function jwsDecode(jwsSig, opts) {
  opts = opts || {};
  jwsSig = tostring(jwsSig);

  if (!isValidJws(jwsSig))
    return null;

  var header = headerFromJWS(jwsSig);

  if (!header)
    return null;

  var payload = payloadFromJWS(jwsSig);
  if (header.typ === 'JWT' || opts.json)
    payload = JSON.parse(payload, opts.encoding);

  return {
    header: header,
    payload: payload,
    signature: signatureFromJWS(jwsSig)
  };
}

function VerifyStream(opts) {
  opts = opts || {};
  var secretOrKey = opts.secret||opts.publicKey||opts.key;
  var secretStream = new dataStream(secretOrKey);
  this.readable = true;
  this.algorithm = opts.algorithm;
  this.encoding = opts.encoding;
  this.secret = this.publicKey = this.key = secretStream;
  this.signature = new dataStream(opts.signature);
  this.secret.once('close', function () {
    if (!this.signature.writable && this.readable)
      this.verify();
  }.bind(this));

  this.signature.once('close', function () {
    if (!this.secret.writable && this.readable)
      this.verify();
  }.bind(this));
}
util__default['default'].inherits(VerifyStream, Stream__default['default']);
VerifyStream.prototype.verify = function verify() {
  try {
    var valid = jwsVerify(this.signature.buffer, this.algorithm, this.key.buffer);
    var obj = jwsDecode(this.signature.buffer, this.encoding);
    this.emit('done', valid, obj);
    this.emit('data', valid);
    this.emit('end');
    this.readable = false;
    return valid;
  } catch (e) {
    this.readable = false;
    this.emit('error', e);
    this.emit('close');
  }
};

VerifyStream.decode = jwsDecode;
VerifyStream.isValid = isValidJws;
VerifyStream.verify = jwsVerify;

var verifyStream = VerifyStream;

/*global exports*/

var ALGORITHMS = [
  'HS256', 'HS384', 'HS512',
  'RS256', 'RS384', 'RS512',
  'PS256', 'PS384', 'PS512',
  'ES256', 'ES384', 'ES512'
];

var ALGORITHMS_1 = ALGORITHMS;
var sign$1 = signStream.sign;
var verify$1 = verifyStream.verify;
var decode$1 = verifyStream.decode;
var isValid = verifyStream.isValid;
var createSign = function createSign(opts) {
  return new signStream(opts);
};
var createVerify = function createVerify(opts) {
  return new verifyStream(opts);
};

var jws$1 = {
	ALGORITHMS: ALGORITHMS_1,
	sign: sign$1,
	verify: verify$1,
	decode: decode$1,
	isValid: isValid,
	createSign: createSign,
	createVerify: createVerify
};

var jws = jws$1;

var decode = function (jwt, options) {
  options = options || {};
  var decoded = jws.decode(jwt, options);
  if (!decoded) { return null; }
  var payload = decoded.payload;

  //try parse the payload
  if(typeof payload === 'string') {
    try {
      var obj = JSON.parse(payload);
      if(obj !== null && typeof obj === 'object') {
        payload = obj;
      }
    } catch (e) { }
  }

  //return header if `complete` option is enabled.  header includes claims
  //such as `kid` and `alg` used to select the key within a JWKS needed to
  //verify the signature
  if (options.complete === true) {
    return {
      header: decoded.header,
      payload: payload,
      signature: decoded.signature
    };
  }
  return payload;
};

var JsonWebTokenError = function (message, error) {
  Error.call(this, message);
  if(Error.captureStackTrace) {
    Error.captureStackTrace(this, this.constructor);
  }
  this.name = 'JsonWebTokenError';
  this.message = message;
  if (error) this.inner = error;
};

JsonWebTokenError.prototype = Object.create(Error.prototype);
JsonWebTokenError.prototype.constructor = JsonWebTokenError;

var JsonWebTokenError_1 = JsonWebTokenError;

var NotBeforeError = function (message, date) {
  JsonWebTokenError_1.call(this, message);
  this.name = 'NotBeforeError';
  this.date = date;
};

NotBeforeError.prototype = Object.create(JsonWebTokenError_1.prototype);

NotBeforeError.prototype.constructor = NotBeforeError;

var NotBeforeError_1 = NotBeforeError;

var TokenExpiredError = function (message, expiredAt) {
  JsonWebTokenError_1.call(this, message);
  this.name = 'TokenExpiredError';
  this.expiredAt = expiredAt;
};

TokenExpiredError.prototype = Object.create(JsonWebTokenError_1.prototype);

TokenExpiredError.prototype.constructor = TokenExpiredError;

var TokenExpiredError_1 = TokenExpiredError;

/**
 * Helpers.
 */
var s = 1000;
var m = s * 60;
var h = m * 60;
var d = h * 24;
var w = d * 7;
var y = d * 365.25;

/**
 * Parse or format the given `val`.
 *
 * Options:
 *
 *  - `long` verbose formatting [false]
 *
 * @param {String|Number} val
 * @param {Object} [options]
 * @throws {Error} throw an error if val is not a non-empty string or a number
 * @return {String|Number}
 * @api public
 */

var ms = function (val, options) {
  options = options || {};
  var type = typeof val;
  if (type === 'string' && val.length > 0) {
    return parse(val);
  } else if (type === 'number' && isFinite(val)) {
    return options.long ? fmtLong(val) : fmtShort(val);
  }
  throw new Error(
    'val is not a non-empty string or a valid number. val=' +
      JSON.stringify(val)
  );
};

/**
 * Parse the given `str` and return milliseconds.
 *
 * @param {String} str
 * @return {Number}
 * @api private
 */

function parse(str) {
  str = String(str);
  if (str.length > 100) {
    return;
  }
  var match = /^(-?(?:\d+)?\.?\d+) *(milliseconds?|msecs?|ms|seconds?|secs?|s|minutes?|mins?|m|hours?|hrs?|h|days?|d|weeks?|w|years?|yrs?|y)?$/i.exec(
    str
  );
  if (!match) {
    return;
  }
  var n = parseFloat(match[1]);
  var type = (match[2] || 'ms').toLowerCase();
  switch (type) {
    case 'years':
    case 'year':
    case 'yrs':
    case 'yr':
    case 'y':
      return n * y;
    case 'weeks':
    case 'week':
    case 'w':
      return n * w;
    case 'days':
    case 'day':
    case 'd':
      return n * d;
    case 'hours':
    case 'hour':
    case 'hrs':
    case 'hr':
    case 'h':
      return n * h;
    case 'minutes':
    case 'minute':
    case 'mins':
    case 'min':
    case 'm':
      return n * m;
    case 'seconds':
    case 'second':
    case 'secs':
    case 'sec':
    case 's':
      return n * s;
    case 'milliseconds':
    case 'millisecond':
    case 'msecs':
    case 'msec':
    case 'ms':
      return n;
    default:
      return undefined;
  }
}

/**
 * Short format for `ms`.
 *
 * @param {Number} ms
 * @return {String}
 * @api private
 */

function fmtShort(ms) {
  var msAbs = Math.abs(ms);
  if (msAbs >= d) {
    return Math.round(ms / d) + 'd';
  }
  if (msAbs >= h) {
    return Math.round(ms / h) + 'h';
  }
  if (msAbs >= m) {
    return Math.round(ms / m) + 'm';
  }
  if (msAbs >= s) {
    return Math.round(ms / s) + 's';
  }
  return ms + 'ms';
}

/**
 * Long format for `ms`.
 *
 * @param {Number} ms
 * @return {String}
 * @api private
 */

function fmtLong(ms) {
  var msAbs = Math.abs(ms);
  if (msAbs >= d) {
    return plural(ms, msAbs, d, 'day');
  }
  if (msAbs >= h) {
    return plural(ms, msAbs, h, 'hour');
  }
  if (msAbs >= m) {
    return plural(ms, msAbs, m, 'minute');
  }
  if (msAbs >= s) {
    return plural(ms, msAbs, s, 'second');
  }
  return ms + ' ms';
}

/**
 * Pluralization helper.
 */

function plural(ms, msAbs, n, name) {
  var isPlural = msAbs >= n * 1.5;
  return Math.round(ms / n) + ' ' + name + (isPlural ? 's' : '');
}

var timespan = function (time, iat) {
  var timestamp = iat || Math.floor(Date.now() / 1000);

  if (typeof time === 'string') {
    var milliseconds = ms(time);
    if (typeof milliseconds === 'undefined') {
      return;
    }
    return Math.floor(timestamp + milliseconds / 1000);
  } else if (typeof time === 'number') {
    return timestamp + time;
  } else {
    return;
  }

};

var semver = defaultHandler.createCommonjsModule(function (module, exports) {
exports = module.exports = SemVer;

var debug;
/* istanbul ignore next */
if (typeof process === 'object' &&
    process.env &&
    process.env.NODE_DEBUG &&
    /\bsemver\b/i.test(process.env.NODE_DEBUG)) {
  debug = function () {
    var args = Array.prototype.slice.call(arguments, 0);
    args.unshift('SEMVER');
    console.log.apply(console, args);
  };
} else {
  debug = function () {};
}

// Note: this is the semver.org version of the spec that it implements
// Not necessarily the package version of this code.
exports.SEMVER_SPEC_VERSION = '2.0.0';

var MAX_LENGTH = 256;
var MAX_SAFE_INTEGER = Number.MAX_SAFE_INTEGER ||
  /* istanbul ignore next */ 9007199254740991;

// Max safe segment length for coercion.
var MAX_SAFE_COMPONENT_LENGTH = 16;

// The actual regexps go on exports.re
var re = exports.re = [];
var src = exports.src = [];
var R = 0;

// The following Regular Expressions can be used for tokenizing,
// validating, and parsing SemVer version strings.

// ## Numeric Identifier
// A single `0`, or a non-zero digit followed by zero or more digits.

var NUMERICIDENTIFIER = R++;
src[NUMERICIDENTIFIER] = '0|[1-9]\\d*';
var NUMERICIDENTIFIERLOOSE = R++;
src[NUMERICIDENTIFIERLOOSE] = '[0-9]+';

// ## Non-numeric Identifier
// Zero or more digits, followed by a letter or hyphen, and then zero or
// more letters, digits, or hyphens.

var NONNUMERICIDENTIFIER = R++;
src[NONNUMERICIDENTIFIER] = '\\d*[a-zA-Z-][a-zA-Z0-9-]*';

// ## Main Version
// Three dot-separated numeric identifiers.

var MAINVERSION = R++;
src[MAINVERSION] = '(' + src[NUMERICIDENTIFIER] + ')\\.' +
                   '(' + src[NUMERICIDENTIFIER] + ')\\.' +
                   '(' + src[NUMERICIDENTIFIER] + ')';

var MAINVERSIONLOOSE = R++;
src[MAINVERSIONLOOSE] = '(' + src[NUMERICIDENTIFIERLOOSE] + ')\\.' +
                        '(' + src[NUMERICIDENTIFIERLOOSE] + ')\\.' +
                        '(' + src[NUMERICIDENTIFIERLOOSE] + ')';

// ## Pre-release Version Identifier
// A numeric identifier, or a non-numeric identifier.

var PRERELEASEIDENTIFIER = R++;
src[PRERELEASEIDENTIFIER] = '(?:' + src[NUMERICIDENTIFIER] +
                            '|' + src[NONNUMERICIDENTIFIER] + ')';

var PRERELEASEIDENTIFIERLOOSE = R++;
src[PRERELEASEIDENTIFIERLOOSE] = '(?:' + src[NUMERICIDENTIFIERLOOSE] +
                                 '|' + src[NONNUMERICIDENTIFIER] + ')';

// ## Pre-release Version
// Hyphen, followed by one or more dot-separated pre-release version
// identifiers.

var PRERELEASE = R++;
src[PRERELEASE] = '(?:-(' + src[PRERELEASEIDENTIFIER] +
                  '(?:\\.' + src[PRERELEASEIDENTIFIER] + ')*))';

var PRERELEASELOOSE = R++;
src[PRERELEASELOOSE] = '(?:-?(' + src[PRERELEASEIDENTIFIERLOOSE] +
                       '(?:\\.' + src[PRERELEASEIDENTIFIERLOOSE] + ')*))';

// ## Build Metadata Identifier
// Any combination of digits, letters, or hyphens.

var BUILDIDENTIFIER = R++;
src[BUILDIDENTIFIER] = '[0-9A-Za-z-]+';

// ## Build Metadata
// Plus sign, followed by one or more period-separated build metadata
// identifiers.

var BUILD = R++;
src[BUILD] = '(?:\\+(' + src[BUILDIDENTIFIER] +
             '(?:\\.' + src[BUILDIDENTIFIER] + ')*))';

// ## Full Version String
// A main version, followed optionally by a pre-release version and
// build metadata.

// Note that the only major, minor, patch, and pre-release sections of
// the version string are capturing groups.  The build metadata is not a
// capturing group, because it should not ever be used in version
// comparison.

var FULL = R++;
var FULLPLAIN = 'v?' + src[MAINVERSION] +
                src[PRERELEASE] + '?' +
                src[BUILD] + '?';

src[FULL] = '^' + FULLPLAIN + '$';

// like full, but allows v1.2.3 and =1.2.3, which people do sometimes.
// also, 1.0.0alpha1 (prerelease without the hyphen) which is pretty
// common in the npm registry.
var LOOSEPLAIN = '[v=\\s]*' + src[MAINVERSIONLOOSE] +
                 src[PRERELEASELOOSE] + '?' +
                 src[BUILD] + '?';

var LOOSE = R++;
src[LOOSE] = '^' + LOOSEPLAIN + '$';

var GTLT = R++;
src[GTLT] = '((?:<|>)?=?)';

// Something like "2.*" or "1.2.x".
// Note that "x.x" is a valid xRange identifer, meaning "any version"
// Only the first item is strictly required.
var XRANGEIDENTIFIERLOOSE = R++;
src[XRANGEIDENTIFIERLOOSE] = src[NUMERICIDENTIFIERLOOSE] + '|x|X|\\*';
var XRANGEIDENTIFIER = R++;
src[XRANGEIDENTIFIER] = src[NUMERICIDENTIFIER] + '|x|X|\\*';

var XRANGEPLAIN = R++;
src[XRANGEPLAIN] = '[v=\\s]*(' + src[XRANGEIDENTIFIER] + ')' +
                   '(?:\\.(' + src[XRANGEIDENTIFIER] + ')' +
                   '(?:\\.(' + src[XRANGEIDENTIFIER] + ')' +
                   '(?:' + src[PRERELEASE] + ')?' +
                   src[BUILD] + '?' +
                   ')?)?';

var XRANGEPLAINLOOSE = R++;
src[XRANGEPLAINLOOSE] = '[v=\\s]*(' + src[XRANGEIDENTIFIERLOOSE] + ')' +
                        '(?:\\.(' + src[XRANGEIDENTIFIERLOOSE] + ')' +
                        '(?:\\.(' + src[XRANGEIDENTIFIERLOOSE] + ')' +
                        '(?:' + src[PRERELEASELOOSE] + ')?' +
                        src[BUILD] + '?' +
                        ')?)?';

var XRANGE = R++;
src[XRANGE] = '^' + src[GTLT] + '\\s*' + src[XRANGEPLAIN] + '$';
var XRANGELOOSE = R++;
src[XRANGELOOSE] = '^' + src[GTLT] + '\\s*' + src[XRANGEPLAINLOOSE] + '$';

// Coercion.
// Extract anything that could conceivably be a part of a valid semver
var COERCE = R++;
src[COERCE] = '(?:^|[^\\d])' +
              '(\\d{1,' + MAX_SAFE_COMPONENT_LENGTH + '})' +
              '(?:\\.(\\d{1,' + MAX_SAFE_COMPONENT_LENGTH + '}))?' +
              '(?:\\.(\\d{1,' + MAX_SAFE_COMPONENT_LENGTH + '}))?' +
              '(?:$|[^\\d])';

// Tilde ranges.
// Meaning is "reasonably at or greater than"
var LONETILDE = R++;
src[LONETILDE] = '(?:~>?)';

var TILDETRIM = R++;
src[TILDETRIM] = '(\\s*)' + src[LONETILDE] + '\\s+';
re[TILDETRIM] = new RegExp(src[TILDETRIM], 'g');
var tildeTrimReplace = '$1~';

var TILDE = R++;
src[TILDE] = '^' + src[LONETILDE] + src[XRANGEPLAIN] + '$';
var TILDELOOSE = R++;
src[TILDELOOSE] = '^' + src[LONETILDE] + src[XRANGEPLAINLOOSE] + '$';

// Caret ranges.
// Meaning is "at least and backwards compatible with"
var LONECARET = R++;
src[LONECARET] = '(?:\\^)';

var CARETTRIM = R++;
src[CARETTRIM] = '(\\s*)' + src[LONECARET] + '\\s+';
re[CARETTRIM] = new RegExp(src[CARETTRIM], 'g');
var caretTrimReplace = '$1^';

var CARET = R++;
src[CARET] = '^' + src[LONECARET] + src[XRANGEPLAIN] + '$';
var CARETLOOSE = R++;
src[CARETLOOSE] = '^' + src[LONECARET] + src[XRANGEPLAINLOOSE] + '$';

// A simple gt/lt/eq thing, or just "" to indicate "any version"
var COMPARATORLOOSE = R++;
src[COMPARATORLOOSE] = '^' + src[GTLT] + '\\s*(' + LOOSEPLAIN + ')$|^$';
var COMPARATOR = R++;
src[COMPARATOR] = '^' + src[GTLT] + '\\s*(' + FULLPLAIN + ')$|^$';

// An expression to strip any whitespace between the gtlt and the thing
// it modifies, so that `> 1.2.3` ==> `>1.2.3`
var COMPARATORTRIM = R++;
src[COMPARATORTRIM] = '(\\s*)' + src[GTLT] +
                      '\\s*(' + LOOSEPLAIN + '|' + src[XRANGEPLAIN] + ')';

// this one has to use the /g flag
re[COMPARATORTRIM] = new RegExp(src[COMPARATORTRIM], 'g');
var comparatorTrimReplace = '$1$2$3';

// Something like `1.2.3 - 1.2.4`
// Note that these all use the loose form, because they'll be
// checked against either the strict or loose comparator form
// later.
var HYPHENRANGE = R++;
src[HYPHENRANGE] = '^\\s*(' + src[XRANGEPLAIN] + ')' +
                   '\\s+-\\s+' +
                   '(' + src[XRANGEPLAIN] + ')' +
                   '\\s*$';

var HYPHENRANGELOOSE = R++;
src[HYPHENRANGELOOSE] = '^\\s*(' + src[XRANGEPLAINLOOSE] + ')' +
                        '\\s+-\\s+' +
                        '(' + src[XRANGEPLAINLOOSE] + ')' +
                        '\\s*$';

// Star ranges basically just allow anything at all.
var STAR = R++;
src[STAR] = '(<|>)?=?\\s*\\*';

// Compile to actual regexp objects.
// All are flag-free, unless they were created above with a flag.
for (var i = 0; i < R; i++) {
  debug(i, src[i]);
  if (!re[i]) {
    re[i] = new RegExp(src[i]);
  }
}

exports.parse = parse;
function parse (version, options) {
  if (!options || typeof options !== 'object') {
    options = {
      loose: !!options,
      includePrerelease: false
    };
  }

  if (version instanceof SemVer) {
    return version
  }

  if (typeof version !== 'string') {
    return null
  }

  if (version.length > MAX_LENGTH) {
    return null
  }

  var r = options.loose ? re[LOOSE] : re[FULL];
  if (!r.test(version)) {
    return null
  }

  try {
    return new SemVer(version, options)
  } catch (er) {
    return null
  }
}

exports.valid = valid;
function valid (version, options) {
  var v = parse(version, options);
  return v ? v.version : null
}

exports.clean = clean;
function clean (version, options) {
  var s = parse(version.trim().replace(/^[=v]+/, ''), options);
  return s ? s.version : null
}

exports.SemVer = SemVer;

function SemVer (version, options) {
  if (!options || typeof options !== 'object') {
    options = {
      loose: !!options,
      includePrerelease: false
    };
  }
  if (version instanceof SemVer) {
    if (version.loose === options.loose) {
      return version
    } else {
      version = version.version;
    }
  } else if (typeof version !== 'string') {
    throw new TypeError('Invalid Version: ' + version)
  }

  if (version.length > MAX_LENGTH) {
    throw new TypeError('version is longer than ' + MAX_LENGTH + ' characters')
  }

  if (!(this instanceof SemVer)) {
    return new SemVer(version, options)
  }

  debug('SemVer', version, options);
  this.options = options;
  this.loose = !!options.loose;

  var m = version.trim().match(options.loose ? re[LOOSE] : re[FULL]);

  if (!m) {
    throw new TypeError('Invalid Version: ' + version)
  }

  this.raw = version;

  // these are actually numbers
  this.major = +m[1];
  this.minor = +m[2];
  this.patch = +m[3];

  if (this.major > MAX_SAFE_INTEGER || this.major < 0) {
    throw new TypeError('Invalid major version')
  }

  if (this.minor > MAX_SAFE_INTEGER || this.minor < 0) {
    throw new TypeError('Invalid minor version')
  }

  if (this.patch > MAX_SAFE_INTEGER || this.patch < 0) {
    throw new TypeError('Invalid patch version')
  }

  // numberify any prerelease numeric ids
  if (!m[4]) {
    this.prerelease = [];
  } else {
    this.prerelease = m[4].split('.').map(function (id) {
      if (/^[0-9]+$/.test(id)) {
        var num = +id;
        if (num >= 0 && num < MAX_SAFE_INTEGER) {
          return num
        }
      }
      return id
    });
  }

  this.build = m[5] ? m[5].split('.') : [];
  this.format();
}

SemVer.prototype.format = function () {
  this.version = this.major + '.' + this.minor + '.' + this.patch;
  if (this.prerelease.length) {
    this.version += '-' + this.prerelease.join('.');
  }
  return this.version
};

SemVer.prototype.toString = function () {
  return this.version
};

SemVer.prototype.compare = function (other) {
  debug('SemVer.compare', this.version, this.options, other);
  if (!(other instanceof SemVer)) {
    other = new SemVer(other, this.options);
  }

  return this.compareMain(other) || this.comparePre(other)
};

SemVer.prototype.compareMain = function (other) {
  if (!(other instanceof SemVer)) {
    other = new SemVer(other, this.options);
  }

  return compareIdentifiers(this.major, other.major) ||
         compareIdentifiers(this.minor, other.minor) ||
         compareIdentifiers(this.patch, other.patch)
};

SemVer.prototype.comparePre = function (other) {
  if (!(other instanceof SemVer)) {
    other = new SemVer(other, this.options);
  }

  // NOT having a prerelease is > having one
  if (this.prerelease.length && !other.prerelease.length) {
    return -1
  } else if (!this.prerelease.length && other.prerelease.length) {
    return 1
  } else if (!this.prerelease.length && !other.prerelease.length) {
    return 0
  }

  var i = 0;
  do {
    var a = this.prerelease[i];
    var b = other.prerelease[i];
    debug('prerelease compare', i, a, b);
    if (a === undefined && b === undefined) {
      return 0
    } else if (b === undefined) {
      return 1
    } else if (a === undefined) {
      return -1
    } else if (a === b) {
      continue
    } else {
      return compareIdentifiers(a, b)
    }
  } while (++i)
};

// preminor will bump the version up to the next minor release, and immediately
// down to pre-release. premajor and prepatch work the same way.
SemVer.prototype.inc = function (release, identifier) {
  switch (release) {
    case 'premajor':
      this.prerelease.length = 0;
      this.patch = 0;
      this.minor = 0;
      this.major++;
      this.inc('pre', identifier);
      break
    case 'preminor':
      this.prerelease.length = 0;
      this.patch = 0;
      this.minor++;
      this.inc('pre', identifier);
      break
    case 'prepatch':
      // If this is already a prerelease, it will bump to the next version
      // drop any prereleases that might already exist, since they are not
      // relevant at this point.
      this.prerelease.length = 0;
      this.inc('patch', identifier);
      this.inc('pre', identifier);
      break
    // If the input is a non-prerelease version, this acts the same as
    // prepatch.
    case 'prerelease':
      if (this.prerelease.length === 0) {
        this.inc('patch', identifier);
      }
      this.inc('pre', identifier);
      break

    case 'major':
      // If this is a pre-major version, bump up to the same major version.
      // Otherwise increment major.
      // 1.0.0-5 bumps to 1.0.0
      // 1.1.0 bumps to 2.0.0
      if (this.minor !== 0 ||
          this.patch !== 0 ||
          this.prerelease.length === 0) {
        this.major++;
      }
      this.minor = 0;
      this.patch = 0;
      this.prerelease = [];
      break
    case 'minor':
      // If this is a pre-minor version, bump up to the same minor version.
      // Otherwise increment minor.
      // 1.2.0-5 bumps to 1.2.0
      // 1.2.1 bumps to 1.3.0
      if (this.patch !== 0 || this.prerelease.length === 0) {
        this.minor++;
      }
      this.patch = 0;
      this.prerelease = [];
      break
    case 'patch':
      // If this is not a pre-release version, it will increment the patch.
      // If it is a pre-release it will bump up to the same patch version.
      // 1.2.0-5 patches to 1.2.0
      // 1.2.0 patches to 1.2.1
      if (this.prerelease.length === 0) {
        this.patch++;
      }
      this.prerelease = [];
      break
    // This probably shouldn't be used publicly.
    // 1.0.0 "pre" would become 1.0.0-0 which is the wrong direction.
    case 'pre':
      if (this.prerelease.length === 0) {
        this.prerelease = [0];
      } else {
        var i = this.prerelease.length;
        while (--i >= 0) {
          if (typeof this.prerelease[i] === 'number') {
            this.prerelease[i]++;
            i = -2;
          }
        }
        if (i === -1) {
          // didn't increment anything
          this.prerelease.push(0);
        }
      }
      if (identifier) {
        // 1.2.0-beta.1 bumps to 1.2.0-beta.2,
        // 1.2.0-beta.fooblz or 1.2.0-beta bumps to 1.2.0-beta.0
        if (this.prerelease[0] === identifier) {
          if (isNaN(this.prerelease[1])) {
            this.prerelease = [identifier, 0];
          }
        } else {
          this.prerelease = [identifier, 0];
        }
      }
      break

    default:
      throw new Error('invalid increment argument: ' + release)
  }
  this.format();
  this.raw = this.version;
  return this
};

exports.inc = inc;
function inc (version, release, loose, identifier) {
  if (typeof (loose) === 'string') {
    identifier = loose;
    loose = undefined;
  }

  try {
    return new SemVer(version, loose).inc(release, identifier).version
  } catch (er) {
    return null
  }
}

exports.diff = diff;
function diff (version1, version2) {
  if (eq(version1, version2)) {
    return null
  } else {
    var v1 = parse(version1);
    var v2 = parse(version2);
    var prefix = '';
    if (v1.prerelease.length || v2.prerelease.length) {
      prefix = 'pre';
      var defaultResult = 'prerelease';
    }
    for (var key in v1) {
      if (key === 'major' || key === 'minor' || key === 'patch') {
        if (v1[key] !== v2[key]) {
          return prefix + key
        }
      }
    }
    return defaultResult // may be undefined
  }
}

exports.compareIdentifiers = compareIdentifiers;

var numeric = /^[0-9]+$/;
function compareIdentifiers (a, b) {
  var anum = numeric.test(a);
  var bnum = numeric.test(b);

  if (anum && bnum) {
    a = +a;
    b = +b;
  }

  return a === b ? 0
    : (anum && !bnum) ? -1
    : (bnum && !anum) ? 1
    : a < b ? -1
    : 1
}

exports.rcompareIdentifiers = rcompareIdentifiers;
function rcompareIdentifiers (a, b) {
  return compareIdentifiers(b, a)
}

exports.major = major;
function major (a, loose) {
  return new SemVer(a, loose).major
}

exports.minor = minor;
function minor (a, loose) {
  return new SemVer(a, loose).minor
}

exports.patch = patch;
function patch (a, loose) {
  return new SemVer(a, loose).patch
}

exports.compare = compare;
function compare (a, b, loose) {
  return new SemVer(a, loose).compare(new SemVer(b, loose))
}

exports.compareLoose = compareLoose;
function compareLoose (a, b) {
  return compare(a, b, true)
}

exports.rcompare = rcompare;
function rcompare (a, b, loose) {
  return compare(b, a, loose)
}

exports.sort = sort;
function sort (list, loose) {
  return list.sort(function (a, b) {
    return exports.compare(a, b, loose)
  })
}

exports.rsort = rsort;
function rsort (list, loose) {
  return list.sort(function (a, b) {
    return exports.rcompare(a, b, loose)
  })
}

exports.gt = gt;
function gt (a, b, loose) {
  return compare(a, b, loose) > 0
}

exports.lt = lt;
function lt (a, b, loose) {
  return compare(a, b, loose) < 0
}

exports.eq = eq;
function eq (a, b, loose) {
  return compare(a, b, loose) === 0
}

exports.neq = neq;
function neq (a, b, loose) {
  return compare(a, b, loose) !== 0
}

exports.gte = gte;
function gte (a, b, loose) {
  return compare(a, b, loose) >= 0
}

exports.lte = lte;
function lte (a, b, loose) {
  return compare(a, b, loose) <= 0
}

exports.cmp = cmp;
function cmp (a, op, b, loose) {
  switch (op) {
    case '===':
      if (typeof a === 'object')
        a = a.version;
      if (typeof b === 'object')
        b = b.version;
      return a === b

    case '!==':
      if (typeof a === 'object')
        a = a.version;
      if (typeof b === 'object')
        b = b.version;
      return a !== b

    case '':
    case '=':
    case '==':
      return eq(a, b, loose)

    case '!=':
      return neq(a, b, loose)

    case '>':
      return gt(a, b, loose)

    case '>=':
      return gte(a, b, loose)

    case '<':
      return lt(a, b, loose)

    case '<=':
      return lte(a, b, loose)

    default:
      throw new TypeError('Invalid operator: ' + op)
  }
}

exports.Comparator = Comparator;
function Comparator (comp, options) {
  if (!options || typeof options !== 'object') {
    options = {
      loose: !!options,
      includePrerelease: false
    };
  }

  if (comp instanceof Comparator) {
    if (comp.loose === !!options.loose) {
      return comp
    } else {
      comp = comp.value;
    }
  }

  if (!(this instanceof Comparator)) {
    return new Comparator(comp, options)
  }

  debug('comparator', comp, options);
  this.options = options;
  this.loose = !!options.loose;
  this.parse(comp);

  if (this.semver === ANY) {
    this.value = '';
  } else {
    this.value = this.operator + this.semver.version;
  }

  debug('comp', this);
}

var ANY = {};
Comparator.prototype.parse = function (comp) {
  var r = this.options.loose ? re[COMPARATORLOOSE] : re[COMPARATOR];
  var m = comp.match(r);

  if (!m) {
    throw new TypeError('Invalid comparator: ' + comp)
  }

  this.operator = m[1];
  if (this.operator === '=') {
    this.operator = '';
  }

  // if it literally is just '>' or '' then allow anything.
  if (!m[2]) {
    this.semver = ANY;
  } else {
    this.semver = new SemVer(m[2], this.options.loose);
  }
};

Comparator.prototype.toString = function () {
  return this.value
};

Comparator.prototype.test = function (version) {
  debug('Comparator.test', version, this.options.loose);

  if (this.semver === ANY) {
    return true
  }

  if (typeof version === 'string') {
    version = new SemVer(version, this.options);
  }

  return cmp(version, this.operator, this.semver, this.options)
};

Comparator.prototype.intersects = function (comp, options) {
  if (!(comp instanceof Comparator)) {
    throw new TypeError('a Comparator is required')
  }

  if (!options || typeof options !== 'object') {
    options = {
      loose: !!options,
      includePrerelease: false
    };
  }

  var rangeTmp;

  if (this.operator === '') {
    rangeTmp = new Range(comp.value, options);
    return satisfies(this.value, rangeTmp, options)
  } else if (comp.operator === '') {
    rangeTmp = new Range(this.value, options);
    return satisfies(comp.semver, rangeTmp, options)
  }

  var sameDirectionIncreasing =
    (this.operator === '>=' || this.operator === '>') &&
    (comp.operator === '>=' || comp.operator === '>');
  var sameDirectionDecreasing =
    (this.operator === '<=' || this.operator === '<') &&
    (comp.operator === '<=' || comp.operator === '<');
  var sameSemVer = this.semver.version === comp.semver.version;
  var differentDirectionsInclusive =
    (this.operator === '>=' || this.operator === '<=') &&
    (comp.operator === '>=' || comp.operator === '<=');
  var oppositeDirectionsLessThan =
    cmp(this.semver, '<', comp.semver, options) &&
    ((this.operator === '>=' || this.operator