Filter messages socially

1 files changed, 86 insertions, 0 deletions

diff --git a/lib/app.js b/lib/app.js
index 5cc4e62..3db24b8 100644
--- a/lib/app.js
+++ b/lib/app.js
@@ -48,6 +48,8 @@ function App(sbot, config) {
   this.reverseEmojiNameCache = lru(500)
   this.getBlobSize = memo({cache: this.blobSizeCache = lru(100)},
     sbot.blobs.size.bind(sbot.blobs))
+  this.getFollows = memo(this._getFollows.bind(this))
+  this.getVotes = memo({cache: lru(100)}, this._getVotes.bind(this))
 
   this.unboxMsg = this.unboxMsg.bind(this)
 
@@ -671,3 +673,87 @@ App.prototype.getNpmReadme = function (tarballId, cb) {
     cb(null, text, true)
   })
 }
+
+App.prototype.filterMsg = function (msg, opts, cb) {
+  var self = this
+  var myId = self.sbot.id
+  var author = msg.value && msg.value.author
+  var show = (opts.filter !== 'invert')
+  if (opts.filter === 'all'
+   || author === myId
+   || author === opts.feed
+   || msg.key === opts.msgId) return cb(null, show)
+  self.getFollows(myId, function (err, follows) {
+    if (err) return cb(err)
+    if (follows[author]) return cb(null, show)
+    self.getVotes(msg.key, function (err, votes) {
+      if (err) return cb(err)
+      for (var author in votes) {
+        if (follows[author] && votes[author] > 0) {
+          return cb(null, show)
+        }
+      }
+      return cb(null, !show)
+    })
+  })
+}
+
+App.prototype.isFollowing = function (src, dest, cb) {
+  var self = this
+  self.getFollows(src, function (err, follows) {
+    if (err) return cb(err)
+    return cb(null, follows[dest])
+  })
+}
+
+App.prototype._getFollows = function (id, cb) {
+  var follows = {}
+  function ready(err) {
+    if (!cb) return
+    var _cb = cb
+    cb = null
+    _cb(err, follows)
+  }
+  pull(
+    this.sbot.links2.read({
+      live: true,
+      query: [
+        {$filter: {
+          source: id,
+          rel: [{$prefix: 'contact'}]
+        }},
+        {$map: {
+          following: ['rel', 1],
+          feed: 'dest'
+        }}
+      ]
+    }),
+    pull.drain(function (link) {
+      if (link.sync) return ready()
+      follows[link.feed] = link.following
+    }, ready)
+  )
+}
+
+App.prototype._getVotes = function (id, cb) {
+  var votes = {}
+  pull(
+    this.sbot.links2.read({
+      query: [
+        {$filter: {
+          dest: id,
+          rel: [{$prefix: 'vote'}]
+        }},
+        {$map: {
+          value: ['rel', 1],
+          author: 'source'
+        }}
+      ]
+    }),
+    pull.drain(function (vote) {
+      votes[vote.author] = vote.value
+    }, function (err) {
+      cb(err, votes)
+    })
+  )
+}