1 files changed, 114 insertions, 0 deletions
diff --git a/lib/about.js b/lib/about.js
new file mode 100644
index 0000000..e94b7fc
--- /dev/null
+++ b/lib/about.js
@@ -0,0 +1,114 @@
+var pull = require('pull-stream')
+var multicb = require('multicb')
+var cat = require('pull-cat')
+var u = require('./util')
+
+module.exports = About
+
+function About(app, myId) {
+  this.app = app
+  this.myId = myId
+}
+
+About.prototype.createAboutOpStream = function (id) {
+  return pull(
+    this.app.sbot.links({dest: id, rel: 'about', values: true, reverse: true}),
+    pull.map(function (msg) {
+      var c = msg.value.content || {}
+      return Object.keys(c).filter(function (key) {
+        return key !== 'about'
+          && key !== 'type'
+          && key !== 'recps'
+      }).map(function (key) {
+        var value = u.linkDest(c[key])
+        // if (u.isRef(value)) value = {link: value}
+        return {
+          id: msg.key,
+          author: msg.value.author,
+          timestamp: msg.value.timestamp,
+          prop: key,
+          value: value,
+          remove: value && typeof value === 'object' && value.remove,
+        }
+      })
+    }),
+    pull.flatten()
+  )
+}
+
+About.prototype.createAboutStreams = function (id) {
+  var ops = this.createAboutOpStream(id)
+  var scalars = {/* author: {prop: value} */}
+  var sets = {/* author: {prop: {link}} */}
+
+  var setsDone = multicb({pluck: 1, spread: true})
+  setsDone()(null, pull.values([]))
+  return {
+    scalars: pull(
+      ops,
+      pull.unique(function (op) {
+        return op.author + '-' + op.prop + '-'
+      }),
+      pull.filter(function (op) {
+        return !op.remove
+      })
+    ),
+    sets: u.readNext(setsDone)
+  }
+}
+
+function computeTopAbout(aboutByFeed) {
+  var propValueCounts = {/* prop: {value: count} */}
+  var topValues = {/* prop: value */}
+  var topValueCounts = {/* prop: count */}
+  for (var feed in aboutByFeed) {
+    var feedAbout = aboutByFeed[feed]
+    for (var prop in feedAbout) {
+      var value = feedAbout[prop]
+      var valueCounts = propValueCounts[prop] || (propValueCounts[prop] = {})
+      var count = (valueCounts[value] || 0) + 1
+      valueCounts[value] = count
+      if (count > (topValueCounts[prop] || 0)) {
+        topValueCounts[prop] = count
+        topValues[prop] = value
+      }
+    }
+  }
+  return topValues
+}
+
+About.prototype.get = function (dest, cb) {
+  var self = this
+  var aboutByFeed = {}
+  pull(
+    cat([
+      dest[0] === '%' && self.app.pullGetMsg(dest),
+      self.app.sbot.links({
+        rel: 'about',
+        dest: dest,
+        values: true,
+      })
+    ]),
+    self.app.unboxMessages(),
+    pull.drain(function (msg) {
+      var author = msg.value.author
+      var c = msg.value.content
+      if (!c) return
+      var about = aboutByFeed[author] || (aboutByFeed[author] = {})
+      if (c.name) about.name = c.name
+      if (c.image) about.image = u.linkDest(c.image)
+      if (c.description) about.description = c.description
+    }, function (err) {
+      if (err) return cb(err)
+      // bias the author's choices by giving them an extra vote
+      aboutByFeed._author = aboutByFeed[dest]
+      var about = {}
+      var myAbout = aboutByFeed[self.myId] || {}
+      var topAbout = computeTopAbout(aboutByFeed)
+      for (var k in topAbout) about[k] = topAbout[k]
+      // always prefer own choices
+      for (var k in myAbout) about[k] = myAbout[k]
+      cb(null, about)
+    })
+  )
+}