var Chainsaw = require('chainsaw'); 
var EventEmitter = require('events').EventEmitter; 
var Buffers = require('buffers'); 
var Vars = require('./lib/vars.js'); 
var Stream = require('stream').Stream; 
exports = module.exports = function (bufOrEm, eventName){ 
if (Buffer.isBuffer(bufOrEm)) { 
return exports.parse(bufOrEm); 
} 
var s = exports.stream(); 
if (bufOrEm && bufOrEm.pipe) { 
bufOrEm.pipe(s); 
} 
 else if (bufOrEm) { 
bufOrEm.on(eventName || 'data', function (buf){ 
_AN_Call_write('write', s, buf); 
} 
); 
bufOrEm.on('end', function (){ 
s.end(); 
} 
); 
} 
return s; 
} 
; 
exports.stream = function (input){ 
if (input) return exports.apply(null , arguments); 
var pending = null ; 
function getBytes(bytes, cb, skip){ 
pending = { 
bytes: bytes,
skip: skip,
cb: function (buf){ 
pending = null ; 
cb(buf); 
} 
}
; 
dispatch(); 
} 
var offset = null ; 
function dispatch(){ 
if (!pending) { 
if (caughtEnd) done = true ; 
return ; 
} 
if (typeof pending === 'function') { 
pending(); 
} 
 else { 
var bytes = offset + pending.bytes; 
if (_AN_Read_length('length', buffers) >= bytes) { 
var buf; 
if (offset == null ) { 
buf = buffers.splice(0, bytes); 
if (!pending.skip) { 
buf = buf.slice(); 
} 
} 
 else { 
if (!pending.skip) { 
buf = buffers.slice(offset, bytes); 
} 
offset = bytes; 
} 
if (pending.skip) { 
pending.cb(); 
} 
 else { 
pending.cb(buf); 
} 
} 
} 
} 
function builder(saw){ 
function next(){ 
if (!done) saw.next(); 
} 
var self = words(function (bytes, cb){ 
return function (name){ 
getBytes(bytes, function (buf){ 
vars.set(name, cb(buf)); 
next(); 
} 
); 
} 
; 
} 
); 
self.tap = function (cb){ 
saw.nest(cb, vars.store); 
} 
; 
self.into = function (key, cb){ 
if (!vars.get(key)) vars.set(key, { 
}
); 
var parent = vars; 
vars = Vars(parent.get(key)); 
saw.nest(function (){ 
cb.apply(this, arguments); 
this.tap(function (){ 
vars = parent; 
} 
); 
} 
, vars.store); 
} 
; 
self.flush = function (){ 
vars.store = { 
}
; 
next(); 
} 
; 
self.loop = function (cb){ 
var end = false ; 
saw.nest(false , function loop(){ 
this.vars = vars.store; 
cb.call(this, function (){ 
end = true ; 
next(); 
} 
, vars.store); 
this.tap(function (){ 
if (end) saw.next(); 
 else loop.call(this); 
} 
.bind(this)); 
} 
, vars.store); 
} 
; 
self.buffer = function (name, bytes){ 
if (typeof bytes === 'string') { 
bytes = vars.get(bytes); 
} 
getBytes(bytes, function (buf){ 
vars.set(name, buf); 
next(); 
} 
); 
} 
; 
self.skip = function (bytes){ 
if (typeof bytes === 'string') { 
bytes = vars.get(bytes); 
} 
getBytes(bytes, function (){ 
next(); 
} 
); 
} 
; 
self.scan = function find(name, search){ 
if (typeof search === 'string') { 
search = new Buffer(search); 
} 
 else if (!Buffer.isBuffer(search)) { 
throw new Error('search must be a Buffer or a string')
} 
var taken = 0; 
pending = function (){ 
var pos = buffers.indexOf(search, offset + taken); 
var i = pos - offset - taken; 
if (pos !== -1) { 
pending = null ; 
if (offset != null ) { 
vars.set(name, buffers.slice(offset, offset + taken + i)); 
offset += taken + i + _AN_Read_length('length', search); 
} 
 else { 
vars.set(name, buffers.slice(0, taken + i)); 
buffers.splice(0, taken + i + _AN_Read_length('length', search)); 
} 
next(); 
dispatch(); 
} 
 else { 
i = Math.max(_AN_Read_length('length', buffers) - _AN_Read_length('length', search) - offset - taken, 0); 
} 
taken += i; 
} 
; 
dispatch(); 
} 
; 
self.peek = function (cb){ 
offset = 0; 
saw.nest(function (){ 
cb.call(this, vars.store); 
this.tap(function (){ 
offset = null ; 
} 
); 
} 
); 
} 
; 
return self; 
} 
; 
var stream = Chainsaw.light(builder); 
stream.writable = true ; 
var buffers = Buffers(); 
stream.write = function (buf){ 
buffers.push(buf); 
dispatch(); 
} 
; 
var vars = Vars(); 
var done = false , caughtEnd = false ; 
stream.end = function (){ 
caughtEnd = true ; 
} 
; 
stream.pipe = Stream.prototype.pipe; 
Object.getOwnPropertyNames(EventEmitter.prototype).forEach(function (name){ 
stream[name] = EventEmitter.prototype[name]; 
} 
); 
return stream; 
} 
; 
exports.parse = function parse(buffer){ 
var self = words(function (bytes, cb){ 
return function (name){ 
if (offset + bytes <= _AN_Read_length('length', buffer)) { 
var buf = buffer.slice(offset, offset + bytes); 
offset += bytes; 
vars.set(name, cb(buf)); 
} 
 else { 
vars.set(name, null ); 
} 
return self; 
} 
; 
} 
); 
var offset = 0; 
var vars = Vars(); 
self.vars = vars.store; 
self.tap = function (cb){ 
cb.call(self, vars.store); 
return self; 
} 
; 
self.into = function (key, cb){ 
if (!vars.get(key)) { 
vars.set(key, { 
}
); 
} 
var parent = vars; 
vars = Vars(parent.get(key)); 
cb.call(self, vars.store); 
vars = parent; 
return self; 
} 
; 
self.loop = function (cb){ 
var end = false ; 
var ender = function (){ 
end = true ; 
} 
; 
while (end === false ){ 
cb.call(self, ender, vars.store); 
} 
return self; 
} 
; 
self.buffer = function (name, size){ 
if (typeof size === 'string') { 
size = vars.get(size); 
} 
var buf = buffer.slice(offset, Math.min(_AN_Read_length('length', buffer), offset + size)); 
offset += size; 
vars.set(name, buf); 
return self; 
} 
; 
self.skip = function (bytes){ 
if (typeof bytes === 'string') { 
bytes = vars.get(bytes); 
} 
offset += bytes; 
return self; 
} 
; 
self.scan = function (name, search){ 
if (typeof search === 'string') { 
search = new Buffer(search); 
} 
 else if (!Buffer.isBuffer(search)) { 
throw new Error('search must be a Buffer or a string')
} 
vars.set(name, null ); 
for (var i = 0; 
i + offset <= _AN_Read_length('length', buffer) - _AN_Read_length('length', search) + 1; i++ ){ 
for (var j = 0; 
j < _AN_Read_length('length', search) && buffer[offset + i + j] === search[j]; j++ ); 
if (j === _AN_Read_length('length', search)) break ; 
} 
vars.set(name, buffer.slice(offset, offset + i)); 
offset += i + _AN_Read_length('length', search); 
return self; 
} 
; 
self.peek = function (cb){ 
var was = offset; 
cb.call(self, vars.store); 
offset = was; 
return self; 
} 
; 
self.flush = function (){ 
vars.store = { 
}
; 
return self; 
} 
; 
self.eof = function (){ 
return offset >= _AN_Read_length('length', buffer); 
} 
; 
return self; 
} 
; 
function decodeLEu(bytes){ 
var acc = 0; 
for (var i = 0; 
i < _AN_Read_length('length', bytes); i++ ){ 
acc += Math.pow(256, i) * bytes[i]; 
} 
return acc; 
} 
function decodeBEu(bytes){ 
var acc = 0; 
for (var i = 0; 
i < _AN_Read_length('length', bytes); i++ ){ 
acc += Math.pow(256, _AN_Read_length('length', bytes) - i - 1) * bytes[i]; 
} 
return acc; 
} 
function decodeBEs(bytes){ 
var val = decodeBEu(bytes); 
if ((bytes[0] & 128) == 128) { 
val -= Math.pow(256, _AN_Read_length('length', bytes)); 
} 
return val; 
} 
function decodeLEs(bytes){ 
var val = decodeLEu(bytes); 
if ((bytes[_AN_Read_length('length', bytes) - 1] & 128) == 128) { 
val -= Math.pow(256, _AN_Read_length('length', bytes)); 
} 
return val; 
} 
function words(decode){ 
var self = { 
}
; 
[1, 2, 4, 8] .forEach(function (bytes){ 
var bits = bytes * 8; 
self['word' + bits + 'le'] = self['word' + bits + 'lu'] = decode(bytes, decodeLEu); 
self['word' + bits + 'ls'] = decode(bytes, decodeLEs); 
self['word' + bits + 'be'] = self['word' + bits + 'bu'] = decode(bytes, decodeBEu); 
self['word' + bits + 'bs'] = decode(bytes, decodeBEs); 
} 
); 
self.word8 = self.word8u = self.word8be; 
self.word8s = self.word8bs; 
return self; 
}