git ssb

1
var Value = require('@mmckegg/mutant/value')
2
var computed = require('@mmckegg/mutant/computed')
3
var MutantDict = require('@mmckegg/mutant/dict')
4
var MutantStruct = require('@mmckegg/mutant/struct')
5
6
module.exports = function InfoCache () {
7
  var likesLookup = {}
8
  var channelsLookup = MutantDict()
9
10
  var channels = computed(channelsLookup, (lookup) => {
11
    var values = Object.keys(lookup).map(x => lookup[x]).sort((a, b) => b.updatedAt - a.updatedAt)
12
    return values
13
  }, {nextTick: true})
14
15
  return { getLikes, channels, updateFrom }
16
17
  function getLikes (msgId) {
18
    if (!likesLookup[msgId]) {
19
      likesLookup[msgId] = Value({})
20
    }
21
    return likesLookup[msgId]
22
  }
23
24
  function updateFrom (msg) {
25
    if (msg.key && msg.value && msg.value.content) {
26
      var c = msg.value.content
27
      if (c.type === 'vote') {
28
        if (msg.value.content.vote && msg.value.content.vote.link) {
29
          var likes = getLikes(msg.value.content.vote.link)()
30
          if (!likes[msg.value.author] || likes[msg.value.author][1] < msg.timestamp) {
31
            likes[msg.value.author] = [msg.value.content.vote.value > 0, msg.timestamp]
32
            getLikes(msg.value.content.vote.link).set(likes)
33
          }
34
        }
35
      } else if (c.type === 'post' && typeof c.channel === 'string') {
36
        var name = c.channel.trim()
37
        if (name) {
38
          var channel = channelsLookup.get(name)
39
          if (!channel) {
40
            channel = MutantStruct({
41
              id: name,
42
              updatedAt: Value()
43
            })
44
            channelsLookup.put(name, channel)
45
          }
46
          if (channel.updatedAt() < msg.timestamp) {
47
            channel.updatedAt.set(msg.timestamp)
48
          }
49
        }
50
      }
51
    }
52
  }
53
}
54