1 files changed, 97 insertions, 0 deletions
diff --git a/app/scripts/lib/remote-store.js b/app/scripts/lib/remote-store.js
new file mode 100644
index 000000000..2dbdde811
--- /dev/null
+++ b/app/scripts/lib/remote-store.js
@@ -0,0 +1,97 @@
+const Dnode = require('dnode')
+const inherits = require('util').inherits
+
+module.exports = {
+  HostStore: HostStore,
+  RemoteStore: RemoteStore,
+}
+
+function BaseStore(initState){
+  this._state = initState || {}
+  this._subs = []
+}
+
+BaseStore.prototype.set = function(key, value){
+  throw Error('Not implemented.')
+}
+
+BaseStore.prototype.get = function(key){
+  return this._state[key]
+}
+
+BaseStore.prototype.subscribe = function(fn){
+  this._subs.push(fn)
+  var unsubscribe = this.unsubscribe.bind(this, fn)
+  return unsubscribe
+}
+
+BaseStore.prototype.unsubscribe = function(fn){
+  var index = this._subs.indexOf(fn)
+  if (index !== -1) this._subs.splice(index, 1)
+}
+
+BaseStore.prototype._emitUpdates = function(state){
+  this._subs.forEach(function(handler){
+    handler(state)
+  })
+}
+
+//
+// host
+//
+
+inherits(HostStore, BaseStore)
+function HostStore(initState, opts){
+  BaseStore.call(this, initState)
+}
+
+HostStore.prototype.set = function(key, value){
+  this._state[key] = value
+  process.nextTick(this._emitUpdates.bind(this, this._state))
+}
+
+HostStore.prototype.createStream = function(){
+  var dnode = Dnode({
+    // update: this._didUpdate.bind(this),
+  })
+  dnode.on('remote', this._didConnect.bind(this))
+  return dnode
+}
+
+HostStore.prototype._didConnect = function(remote){
+  this.subscribe(function(state){
+    remote.update(state)
+  })
+  remote.update(this._state)
+}
+
+//
+// remote
+//
+
+inherits(RemoteStore, BaseStore)
+function RemoteStore(initState, opts){
+  BaseStore.call(this, initState)
+  this._remote = null
+}
+
+RemoteStore.prototype.set = function(key, value){
+  this._remote.set(key, value)
+}
+
+RemoteStore.prototype.createStream = function(){
+  var dnode = Dnode({
+    update: this._didUpdate.bind(this),
+  })
+  dnode.once('remote', this._didConnect.bind(this))
+  return dnode
+}
+
+RemoteStore.prototype._didConnect = function(remote){
+  this._remote = remote
+}
+
+RemoteStore.prototype._didUpdate = function(state){
+  this._state = state
+  this._emitUpdates(state)
+}