1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
|
const { EventEmitter } = require('events')
const { PassThrough } = require('readable-stream')
const eos = require('end-of-stream')
const path = require('path')
const render = require('render-media')
const streamToBlob = require('stream-to-blob')
const streamToBlobURL = require('stream-to-blob-url')
const streamToBuffer = require('stream-with-known-length-to-buffer')
const FileStream = require('./file-stream')
class File extends EventEmitter {
constructor (torrent, file) {
super()
this._torrent = torrent
this._destroyed = false
this.name = file.name
this.path = file.path
this.length = file.length
this.offset = file.offset
this.done = false
const start = file.offset
const end = start + file.length - 1
this._startPiece = start / this._torrent.pieceLength | 0
this._endPiece = end / this._torrent.pieceLength | 0
if (this.length === 0) {
this.done = true
this.emit('done')
}
}
get downloaded () {
if (!this._torrent.bitfield) return 0
const { pieces, bitfield, pieceLength } = this._torrent
const { _startPiece: start, _endPiece: end } = this
const piece = pieces[start]
// First piece may have an offset, e.g. irrelevant bytes from the end of
// the previous file
const irrelevantFirstPieceBytes = this.offset % pieceLength
let downloaded = bitfield.get(start)
? pieceLength - irrelevantFirstPieceBytes
: Math.max(pieceLength - irrelevantFirstPieceBytes - piece.missing, 0)
for (let index = start + 1; index <= end; ++index) {
if (bitfield.get(index)) {
// verified data
downloaded += pieceLength
} else {
// "in progress" data
const piece = pieces[index]
downloaded += pieceLength - piece.missing
}
}
// We don't know the end offset, so return this.length if it's oversized.
// e.g. One small file can fit in the middle of a piece.
return Math.min(downloaded, this.length)
}
get progress () {
return this.length ? this.downloaded / this.length : 0
}
select (priority) {
if (this.length === 0) return
this._torrent.select(this._startPiece, this._endPiece, priority)
}
deselect () {
if (this.length === 0) return
this._torrent.deselect(this._startPiece, this._endPiece, false)
}
createReadStream (opts) {
if (this.length === 0) {
const empty = new PassThrough()
process.nextTick(() => {
empty.end()
})
return empty
}
const fileStream = new FileStream(this, opts)
this._torrent.select(fileStream._startPiece, fileStream._endPiece, true, () => {
fileStream._notify()
})
eos(fileStream, () => {
if (this._destroyed) return
if (!this._torrent.destroyed) {
this._torrent.deselect(fileStream._startPiece, fileStream._endPiece, true)
}
})
return fileStream
}
getBuffer (cb) {
streamToBuffer(this.createReadStream(), this.length, cb)
}
getBlob (cb) {
if (typeof window === 'undefined') throw new Error('browser-only method')
streamToBlob(this.createReadStream(), this._getMimeType())
.then(
blob => cb(null, blob),
err => cb(err)
)
}
getBlobURL (cb) {
if (typeof window === 'undefined') throw new Error('browser-only method')
streamToBlobURL(this.createReadStream(), this._getMimeType())
.then(
blobUrl => cb(null, blobUrl),
err => cb(err)
)
}
appendTo (elem, opts, cb) {
if (typeof window === 'undefined') throw new Error('browser-only method')
render.append(this, elem, opts, cb)
}
renderTo (elem, opts, cb) {
if (typeof window === 'undefined') throw new Error('browser-only method')
render.render(this, elem, opts, cb)
}
_getMimeType () {
return render.mime[path.extname(this.name).toLowerCase()]
}
_destroy () {
this._destroyed = true
this._torrent = null
}
}
module.exports = File
|