git ssb

1
var pull = require('pull-stream')
2
var asyncMemo = require('asyncmemo')
3
var u = require('./util')
4
5
module.exports = function (sbot) {
6
  var votes = {}
7
8
  pull(
9
    sbot.links({rel: 'vote', values: true, old: false}),
10
    u.decryptMessages(sbot),
11
    u.readableMessages(),
12
    pull.drain(processMsg, function (err) {
13
      if (err) console.error('vote', err)
14
    })
15
  )
16
17
  return asyncMemo(function (id, cb) {
18
    var result = votes[id] = {
19
      upvoters: {},
20
      downvoters: {},
21
      upvotes: 0,
22
      downvotes: 0
23
    }
24
25
    pull(
26
      sbot.backlinks ? sbot.backlinks.read({
27
        reverse: true,
28
        query: [{$filter: {
29
          dest: id,
30
          value: {
31
            content: {
32
              type: 'vote'
33
            }
34
          }
35
        }}]
36
      }) : sbot.links({dest: id, rel: 'vote', values: true}),
37
      u.decryptMessages(sbot),
38
      u.readableMessages(),
39
      pull.drain(processMsg, function (err) {
40
        cb(err, result)
41
      })
42
    )
43
  })
44
45
  function processMsg(msg) {
46
    var c = msg.value.content
47
    if (!c || !c.vote) return
48
    var result = votes[c.vote.link]
49
    if (!result) return
50
    var vote = c.vote.value
51
    var author = msg.value.author
52
53
    // remove old vote, if any
54
    if (author in result.upvoters) {
55
      result.upvotes--
56
      delete result.upvoters[author]
57
    } else if (author in result.downvoters) {
58
      result.downvotes--
59
      delete result.downvoters[author]
60
    }
61
62
    // add new vote
63
    if (vote > 0) {
64
      result.upvoters[author] = vote
65
      result.upvotes++
66
    } else if (vote < 0) {
67
      result.downvoters[author] = vote
68
      result.downvotes++
69
    }
70
  }
71
}
72