codekingpro/portable-devtools

1const EE = require('events')
2const onProgress = Symbol('onProgress')
3const bars = Symbol('bars')
4const listener = Symbol('listener')
5const normData = Symbol('normData')
6class Client extends EE {
7  constructor ({ normalize = false, stopOnDone = false } = {}) {
8    super()
9    this.normalize = !!normalize
10    this.stopOnDone = !!stopOnDone
11    this[bars] = new Map()
12    this[listener] = null
13  }
14
15  get size () {
16    return this[bars].size
17  }
18
19  get listening () {
20    return !!this[listener]
21  }
22
23  addListener (...args) {
24    return this.on(...args)
25  }
26
27  on (ev, ...args) {
28    if (ev === 'progress' && !this[listener]) {
29      this.start()
30    }
31    return super.on(ev, ...args)
32  }
33
34  off (ev, ...args) {
35    return this.removeListener(ev, ...args)
36  }
37
38  removeListener (ev, ...args) {
39    const ret = super.removeListener(ev, ...args)
40    if (ev === 'progress' && this.listeners(ev).length === 0) {
41      this.stop()
42    }
43    return ret
44  }
45
46  stop () {
47    if (this[listener]) {
48      process.removeListener('progress', this[listener])
49      this[listener] = null
50    }
51  }
52
53  start () {
54    if (!this[listener]) {
55      this[listener] = (...args) => this[onProgress](...args)
56      process.on('progress', this[listener])
57    }
58  }
59
60  [onProgress] (key, data) {
61    data = this[normData](key, data)
62    if (!this[bars].has(key)) {
63      this.emit('bar', key, data)
64    }
65    this[bars].set(key, data)
66    this.emit('progress', key, data)
67    if (data.done) {
68      this[bars].delete(key)
69      this.emit('barDone', key, data)
70      if (this.size === 0) {
71        if (this.stopOnDone) {
72          this.stop()
73        }
74        this.emit('done')
75      }
76    }
77  }
78
79  [normData] (key, data) {
80    const actualValue = data.value
81    const actualTotal = data.total
82    let value = actualValue
83    let total = actualTotal
84    const done = data.done || value >= total
85    if (this.normalize) {
86      const bar = this[bars].get(key)
87      total = 100
88      if (done) {
89        value = 100
90      } else {
91        // show value as a portion of 100
92        const pct = 100 * actualValue / actualTotal
93        if (bar) {
94          // don't ever go backwards, and don't stand still
95          // move at least 1% of the remaining value if it wouldn't move.
96          value = (pct > bar.value) ? pct
97            : (100 - bar.value) / 100 + bar.value
98        }
99      }
100    }
101    // include the key
102    return {
103      ...data,
104      key,
105      name: data.name || key,
106      value,
107      total,
108      actualValue,
109      actualTotal,
110      done,
111    }
112  }
113}
114module.exports = Client
115