git ssb

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// uses lib/flumeview-channels
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var nest = require('depnest')
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var pull = require('pull-stream')
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var { Value, Dict, Struct, computed, resolve, throttle } = require('mutant')
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exports.needs = nest({
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  'sbot.pull.stream': 'first'
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})
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exports.gives = nest({
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  'channel.obs.recent': true
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})
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exports.create = function (api) {
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  var recentChannels = null
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  var channelsLookup = null
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  return nest({
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    'channel.obs.recent': function () {
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      load()
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      return recentChannels
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    }
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  })
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  function load () {
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    if (!recentChannels) {
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      var sync = Value(false)
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      channelsLookup = Dict()
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      pull(
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        api.sbot.pull.stream(sbot => sbot.channels.stream({live: true})),
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        pull.drain(msg => {
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          if (!sync()) {
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            channelsLookup.transaction(() => {
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              for (var channel in msg) {
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                var obs = ChannelRef(channel)
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                obs.set({
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                  id: channel,
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                  updatedAt: msg[channel].timestamp,
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                  count: msg[channel].count
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                })
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                channelsLookup.put(channel, obs)
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              }
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              sync.set(true)
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            })
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          } else {
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            var obs = channelsLookup.get(msg.channel)
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            if (!obs) {
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              obs = ChannelRef(msg.dest)
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              channelsLookup.put(msg.dest, obs)
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            }
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            obs.set({
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              id: msg.channel,
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              updatedAt: Math.max(resolve(obs.updatedAt), msg.timestamp),
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              count: resolve(obs.count) + 1
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            })
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          }
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        })
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      )
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      recentChannels = computed(throttle(channelsLookup, 1000), (lookup) => {
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        var values = Object.keys(lookup).map(x => lookup[x]).sort((a, b) => b.updatedAt - a.updatedAt).map(x => x.id)
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        return values
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      })
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      recentChannels.sync = sync
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    }
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  }
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}
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function ChannelRef (id) {
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  return Struct({
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    id,
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    updatedAt: Value(0),
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    count: Value(0)
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  }, {merge: true})
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}
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