var strm = require('./')

var fs = require('fs')

var createReadStrm = exports.createReadStrm = function (file, opts) {

opts = opts || {}

return function (dest) {

if('function' !== typeof dest)

throw new Error('read-only')

fs.open(file, opts.flags || 'r+', function (err, fd) {

var size = 8192, buffer = new Buffer(size), i = 0

;(function next (err) {

if(err) throw err

fs.read(fd, buffer, 0, size, i, function (err, bytes) {

i += bytes

strm.async(dest

, bytes != size ? buffer.slice(0, bytes) : buffer

, err || bytes == 0 || null, next)

})

})(err)

})

return dest

}

}

var createWriteStrm = exports.createWriteStrm = function (file, opts) {

opts = opts || {}

var fd, i = 0

return strm.reader(function (data, end, cb) {

if(end && !data) return false

if(fd) write()

else fs.open(file, opts.flags || 'w', function (err, _fd) {

if(err) return cb(err)

fd = _fd

write()

})

function write() {

console.log('>>>', data.toString(), '<<<')

fs.write(fd, data, 0, data.length, i, function (err, bytes) {

if(err) return cb(err)

i += bytes

cb()

})

}

})

}

var _waiting = [], _ended

function write (data, end) {

if(end) return _ended = end

var r = process.stdout.write(data)

if(r === false)

process.stdout.once('drain', function () {

_waiting.length && _waiting.shift()(_ended)

})

return _waiting

}

if(!module.parent) {

createReadStrm(process.argv[2])

(write)

}