Merge pull request #160 from vector-im/conferencing

Add conferencing support

docs/conferencing.md

@@ -0,0 +1,52 @@
+# VoIP Conferencing
+
+This is a draft proposal for a naive voice/video conferencing implementation for
+Matrix clients.  There are many possible conferencing architectures possible for
+Matrix (Multipoint Conferencing Unit (MCU); Stream Forwarding Unit (SFU); Peer-
+to-Peer mesh (P2P), etc; events shared in the group room; events shared 1:1;
+possibly even out-of-band signalling).
+
+This is a starting point for a naive MCU implementation which could provide one
+possible Matrix-wide solution in  future, which retains backwards compatibility
+with standard 1:1 calling.
+
+ * A client chooses to initiate a conference for a given room by starting a
+   voice or video call with a 'conference focus' user.  This is a virtual user
+   (typically Application Service) which implements a conferencing bridge.  It
+   isn't defined how the client discovers or selects this user.
+
+ * The conference focus user MUST join the room in which the client has
+   initiated the conference - this may require the client to invite the
+   conference focus user to the room, depending on the room's `join_rules`. The
+   conference focus user needs to be in the room to let the bridge eject users
+   from the conference who have left the room in which it was initiated, and aid
+   discovery of the conference by other users in the room.  The bridge
+   identifies the room to join based on the user ID by which it was invited.
+   The format of this identifier is implementation dependent for now.
+
+ * If a client leaves the group chat room, they MUST be ejected from the
+   conference. If a client leaves the 1:1 room with the conference focus user,
+   they SHOULD be ejected from the conference.
+
+ * For now, rooms can contain multiple conference focus users - it's left to
+   user or client implementation to select which to converge on.  In future this
+   could be mediated using a state event (e.g. `im.vector.call.mcu`), but we
+   can't do that right now as by default normal users can't set arbitrary state
+   events on a room.
+
+ * To participate in the conference, other clients initiates a standard 1:1
+   voice or video call to the conference focus user.
+
+ * For best UX, clients SHOULD show the ongoing voice/video call in the UI
+   context of the group room rather than 1:1 with the focus user.  If a client
+   recognises a conference user present in the room, it MAY chose to highlight
+   this in the UI (e.g. with a "conference ongoing" notification, to aid
+   discovery).  Clients MAY hide the 1:1 room with the focus user (although in
+   future this room could be used for floor control or other direct
+   communication with the conference focus)
+
+ * When all users have left the conference, the 'conference focus' user SHOULD
+   leave the room.
+
+ * If a conference focus user joins a room but does not receive a 1:1 voice or
+   video call, it SHOULD time out after a period of time and leave the room.

skins/base/css/organisms/RoomView.css

@@ -218,3 +218,12 @@ limitations under the License.
     background-color: blue;
     height: 5px;
 }
+
+.mx_RoomView_ongoingConfCallNotification {
+    width: 100%;
+    text-align: center;
+    background-color: #ff0064;
+    color: #fff;
+    font-weight: bold;
+    padding: 6px;
+}

skins/base/css/templates/Login.css

@@ -75,6 +75,22 @@ limitations under the License.
     opacity: 0.8;
 }
 
+.mx_Login_create:link {
+    color: #4a4a4a;
+}
+
+.mx_Login_links {
+    display: block;
+    text-align: center;
+    width: 100%;
+    font-size: 14px;
+    opacity: 0.8;
+}
+
+.mx_Login_links a:link {
+   color: #4a4a4a;
+}
+
 .mx_Login_loader {
     position: absolute;
     left: 50%;
@@ -85,12 +101,10 @@ limitations under the License.
     color: #ff2020;
     font-weight: bold;
     text-align: center;
+/*
     height: 24px;
+*/
     margin-top: 12px;
     margin-bottom: 12px;
 }
 
-.mx_Login_create:link {
-    color: #4a4a4a;
-}
-

skins/base/views/organisms/RoomList.js

@@ -18,7 +18,7 @@ limitations under the License.
 
 var React = require('react');
 var ComponentBroker = require('../../../../src/ComponentBroker');
-
+var CallView = ComponentBroker.get('molecules/voip/CallView');
 var RoomDropTarget = ComponentBroker.get('molecules/RoomDropTarget');
 
 var RoomListController = require("../../../../src/controllers/organisms/RoomList");
@@ -28,8 +28,14 @@ module.exports = React.createClass({
     mixins: [RoomListController],
 
     render: function() {
+        var callElement;
+        if (this.state.show_call_element) {
+            callElement = <CallView className="mx_MatrixChat_callView"/>
+        }
+
         return (
             <div className="mx_RoomList">
+                {callElement}
                 <h2 className="mx_RoomList_favourites_label">Favourites</h2>
                 <RoomDropTarget text="Drop here to favourite"/>
 

skins/base/views/organisms/RoomView.js

@@ -176,6 +176,15 @@ module.exports = React.createClass({
                 roomEdit = <Loader/>;
             }
 
+            var conferenceCallNotification = null;
+            if (this.state.displayConfCallNotification) {
+                conferenceCallNotification = (
+                    <div className="mx_RoomView_ongoingConfCallNotification" onClick={this.onConferenceNotificationClick}>
+                        Ongoing conference call
+                    </div>
+                );
+            }
+
             var fileDropTarget = null;
             if (this.state.draggingFile) {
                 fileDropTarget = <div className="mx_RoomView_fileDropTarget">
@@ -192,6 +201,7 @@ module.exports = React.createClass({
                         onSettingsClick={this.onSettingsClick} onSaveClick={this.onSaveClick} onCancelClick={this.onCancelClick} />
                     <div className="mx_RoomView_auxPanel">
                         <CallView room={this.state.room}/>
+                        { conferenceCallNotification }
                         { roomEdit }
                     </div>
                     <div ref="messageWrapper" className="mx_RoomView_messagePanel" onScroll={ this.onMessageListScroll }>

skins/base/views/pages/MatrixChat.js

@@ -30,7 +30,7 @@ var RoomDirectory = ComponentBroker.get('organisms/RoomDirectory');
 var MatrixToolbar = ComponentBroker.get('molecules/MatrixToolbar');
 var Notifier = ComponentBroker.get('organisms/Notifier');
 
-var MatrixChatController = require("../../../../src/controllers/pages/MatrixChat");
+var MatrixChatController = require('../../../../src/controllers/pages/MatrixChat');
 
 // should be atomised
 var Loader = require("react-loader");
@@ -75,6 +75,7 @@ module.exports = React.createClass({
                     break;
             }
 
+            // TODO: Fix duplication here and do conditionals like we do above
             if (Notifier.supportsDesktopNotifications() && !Notifier.isEnabled() && !Notifier.isToolbarHidden()) {
                 return (
                         <div className="mx_MatrixChat_wrapper">

skins/base/views/templates/Login.js

@@ -165,6 +165,13 @@ module.exports = React.createClass({
                         {this.state.errorText}
                 </div>
                 <a className="mx_Login_create" onClick={this.showRegister} href="#">Create a new account</a>
+                <br/>
+                <div className="mx_Login_links">
+                    <a href="https://medium.com/@Vector">blog</a>&nbsp;&nbsp;&middot;&nbsp;&nbsp;
+                    <a href="https://twitter.com/@VectorCo">twitter</a>&nbsp;&nbsp;&middot;&nbsp;&nbsp;
+                    <a href="https://github.com/vector-im/vector-web">github</a>&nbsp;&nbsp;&middot;&nbsp;&nbsp;
+                    <a href="https://matrix.org">powered by Matrix</a>
+                </div>
             </div>
         );
     },

src/CallHandler.js

@@ -57,6 +57,8 @@ var MatrixClientPeg = require("./MatrixClientPeg");
 var Modal = require("./Modal");
 var ComponentBroker = require('./ComponentBroker');
 var ErrorDialog = ComponentBroker.get("organisms/ErrorDialog");
+var ConferenceCall = require("./ConferenceHandler").ConferenceCall;
+var ConferenceHandler = require("./ConferenceHandler");
 var Matrix = require("matrix-js-sdk");
 var dis = require("./dispatcher");
 
@@ -105,7 +107,7 @@ function _setCallListeners(call) {
             play("ringbackAudio");
         }
         else if (newState === "ended" && oldState === "connected") {
-            _setCallState(call, call.roomId, "ended");
+            _setCallState(undefined, call.roomId, "ended");
             pause("ringbackAudio");
             play("callendAudio");
         }
@@ -153,7 +155,11 @@ function _setCallState(call, roomId, status) {
 dis.register(function(payload) {
     switch (payload.action) {
         case 'place_call':
-            if (calls[payload.room_id]) {
+            if (module.exports.getAnyActiveCall()) {
+                Modal.createDialog(ErrorDialog, {
+                    title: "Existing Call",
+                    description: "You are already in a call."
+                });
                 return; // don't allow >1 call to be placed.
             }
             var room = MatrixClientPeg.get().getRoom(payload.room_id);
@@ -161,40 +167,52 @@ dis.register(function(payload) {
                 console.error("Room %s does not exist.", payload.room_id);
                 return;
             }
-            var members = room.getJoinedMembers();
+
-            if (members.length !== 2) {
+            function placeCall(newCall) {
-                var text = members.length === 1 ? "yourself." : "more than 2 people.";
+                _setCallListeners(newCall);
-                Modal.createDialog(ErrorDialog, {
+                _setCallState(newCall, newCall.roomId, "ringback");
-                    description: "You cannot place a call with " + text
+                if (payload.type === 'voice') {
-                });
+                    newCall.placeVoiceCall();
-                console.error(
+                }
-                    "Fail: There are %s joined members in this room, not 2.",
+                else if (payload.type === 'video') {
-                    room.getJoinedMembers().length
+                    newCall.placeVideoCall(
-                );
+                        payload.remote_element,
-                return;
+                        payload.local_element
-            }
+                    );
-            console.log("Place %s call in %s", payload.type, payload.room_id);
+                }
-            var call = Matrix.createNewMatrixCall(
+                else {
-                MatrixClientPeg.get(), payload.room_id
+                    console.error("Unknown conf call type: %s", payload.type);
-            );
+                }
-            _setCallListeners(call);
-            _setCallState(call, call.roomId, "ringback");
-            if (payload.type === 'voice') {
-                call.placeVoiceCall();
-            }
-            else if (payload.type === 'video') {
-                call.placeVideoCall(
-                    payload.remote_element,
-                    payload.local_element
-                );
-            }
-            else {
-                console.error("Unknown call type: %s", payload.type);
             }
 
+            var members = room.getJoinedMembers();
+            if (members.length <= 1) {
+                Modal.createDialog(ErrorDialog, {
+                    description: "You cannot place a call with yourself."
+                });
+                return;
+            }
+            else if (members.length === 2) {
+                console.log("Place %s call in %s", payload.type, payload.room_id);
+                var call = Matrix.createNewMatrixCall(
+                    MatrixClientPeg.get(), payload.room_id
+                );
+                placeCall(call);
+            }
+            else { // > 2
+                console.log("Place conference call in %s", payload.room_id);
+                var confCall = new ConferenceCall(
+                    MatrixClientPeg.get(), payload.room_id
+                );
+                confCall.setup().done(function(call) {
+                    placeCall(call);
+                }, function(err) {
+                    console.error("Failed to setup conference call: %s", err);
+                });
+            }
             break;
         case 'incoming_call':
-            if (calls[payload.call.roomId]) {
+            if (module.exports.getAnyActiveCall()) {
                 payload.call.hangup("busy");
                 return; // don't allow >1 call to be received, hangup newer one.
             }
@@ -224,7 +242,40 @@ dis.register(function(payload) {
 });
 
 module.exports = {
+
+    getCallForRoom: function(roomId) {
+        return (
+            module.exports.getCall(roomId) ||
+            module.exports.getConferenceCall(roomId)
+        );
+    },
+
     getCall: function(roomId) {
         return calls[roomId] || null;
+    },
+
+    getConferenceCall: function(roomId) {
+        // search for a conference 1:1 call for this group chat room ID
+        var activeCall = module.exports.getAnyActiveCall();
+        if (activeCall && activeCall.confUserId) {
+            var thisRoomConfUserId = ConferenceHandler.getConferenceUserIdForRoom(
+                roomId
+            );
+            if (thisRoomConfUserId === activeCall.confUserId) {
+                return activeCall;
+            }
+        }
+        return null;
+    },
+
+    getAnyActiveCall: function() {
+        var roomsWithCalls = Object.keys(calls);
+        for (var i = 0; i < roomsWithCalls.length; i++) {
+            if (calls[roomsWithCalls[i]] &&
+                    calls[roomsWithCalls[i]].call_state !== "ended") {
+                return calls[roomsWithCalls[i]];
+            }
+        }
+        return null;
     }
 };

src/ConferenceHandler.js

@@ -0,0 +1,94 @@
+"use strict";
+var q = require("q");
+var Matrix = require("matrix-js-sdk");
+var Room = Matrix.Room;
+
+// FIXME: This currently forces Vector to try to hit the matrix.org AS for conferencing.
+// This is bad because it prevents people running their own ASes from being used.
+// This isn't permanent and will be customisable in the future: see the proposal
+// at docs/conferencing.md for more info.
+var USER_PREFIX = "fs_";
+var DOMAIN = "matrix.org";
+
+function ConferenceCall(matrixClient, groupChatRoomId) {
+    this.client = matrixClient;
+    this.groupRoomId = groupChatRoomId;
+    this.confUserId = module.exports.getConferenceUserIdForRoom(this.groupRoomId);
+}
+
+ConferenceCall.prototype.setup = function() {
+    var self = this;
+    return this._joinConferenceUser().then(function() {
+        return self._getConferenceUserRoom();
+    }).then(function(room) {
+        // return a call for *this* room to be placed. We also tack on
+        // confUserId to speed up lookups (else we'd need to loop every room
+        // looking for a 1:1 room with this conf user ID!)
+        var call = Matrix.createNewMatrixCall(self.client, room.roomId);
+        call.confUserId = self.confUserId;
+        return call;
+    });
+};
+
+ConferenceCall.prototype._joinConferenceUser = function() {
+    // Make sure the conference user is in the group chat room
+    var groupRoom = this.client.getRoom(this.groupRoomId);
+    if (!groupRoom) {
+        return q.reject("Bad group room ID");
+    }
+    var member = groupRoom.getMember(this.confUserId);
+    if (member && member.membership === "join") {
+        return q();
+    }
+    return this.client.invite(this.groupRoomId, this.confUserId);
+};
+
+ConferenceCall.prototype._getConferenceUserRoom = function() {
+    // Use an existing 1:1 with the conference user; else make one
+    var rooms = this.client.getRooms();
+    var confRoom = null;
+    for (var i = 0; i < rooms.length; i++) {
+        var confUser = rooms[i].getMember(this.confUserId);
+        if (confUser && confUser.membership === "join" &&
+                rooms[i].getJoinedMembers().length === 2) {
+            confRoom = rooms[i];
+            break;
+        }
+    }
+    if (confRoom) {
+        return q(confRoom);
+    }
+    return this.client.createRoom({
+        preset: "private_chat",
+        invite: [this.confUserId]
+    }).then(function(res) {
+        return new Room(res.room_id);
+    });
+};
+
+/**
+ * Check if this room member is in fact a conference bot.
+ * @param {RoomMember} The room member to check
+ * @return {boolean} True if it is a conference bot.
+ */
+module.exports.isConferenceUser = function(roomMember) {
+    if (roomMember.userId.indexOf("@" + USER_PREFIX) !== 0) {
+        return false;
+    }
+    var base64part = roomMember.userId.split(":")[0].substring(1 + USER_PREFIX.length);
+    if (base64part) {
+        var decoded = new Buffer(base64part, "base64").toString();
+        // ! $STUFF : $STUFF
+        return /^!.+:.+/.test(decoded);
+    }
+    return false;
+};
+
+module.exports.getConferenceUserIdForRoom = function(roomId) {
+    // abuse browserify's core node Buffer support (strip padding ='s)
+    var base64RoomId = new Buffer(roomId).toString("base64").replace(/=/g, "");
+    return "@" + USER_PREFIX + base64RoomId + ":" + DOMAIN;
+};
+
+module.exports.ConferenceCall = ConferenceCall;
+

src/controllers/molecules/RoomHeader.js

@@ -19,6 +19,9 @@ limitations under the License.
 /*
  * State vars:
  * this.state.call_state = the UI state of the call (see CallHandler)
+ *
+ * Props:
+ * room (JS SDK Room)
  */
 
 var React = require('react');
@@ -44,7 +47,7 @@ module.exports = {
     componentDidMount: function() {
         this.dispatcherRef = dis.register(this.onAction);
         if (this.props.room) {
-            var call = CallHandler.getCall(this.props.room.roomId);
+            var call = CallHandler.getCallForRoom(this.props.room.roomId);
             var callState = call ? call.call_state : "ended";
             this.setState({
                 call_state: callState
@@ -57,15 +60,12 @@ module.exports = {
     },
 
     onAction: function(payload) {
-        // if we were given a room_id to track, don't handle anything else.
+        // don't filter out payloads for room IDs other than props.room because
-        if (payload.room_id && this.props.room &&
+        // we may be interested in the conf 1:1 room
-                this.props.room.roomId !== payload.room_id) {
+        if (payload.action !== 'call_state' || !payload.room_id) {
             return;
         }
-        if (payload.action !== 'call_state') {
+        var call = CallHandler.getCallForRoom(payload.room_id);
-            return;
-        }
-        var call = CallHandler.getCall(payload.room_id);
         var callState = call ? call.call_state : "ended";
         this.setState({
             call_state: callState
@@ -87,9 +87,13 @@ module.exports = {
         });
     },
     onHangupClick: function() {
+        var call = CallHandler.getCallForRoom(this.props.room.roomId);
+        if (!call) { return; }
         dis.dispatch({
             action: 'hangup',
-            room_id: this.props.room.roomId
+            // hangup the call for this room, which may not be the room in props
+            // (e.g. conferences which will hangup the 1:1 room instead)
+            room_id: call.roomId
         });
     }
 };

src/controllers/molecules/voip/CallView.js

@@ -17,6 +17,7 @@ limitations under the License.
 'use strict';
 var dis = require("../../../dispatcher");
 var CallHandler = require("../../../CallHandler");
+var MatrixClientPeg = require("../../../MatrixClientPeg");
 
 /*
  * State vars:
@@ -24,14 +25,30 @@ var CallHandler = require("../../../CallHandler");
  *
  * Props:
  * this.props.room = Room (JS SDK)
+ *
+ * Internal state:
+ * this._trackedRoom = (either from props.room or programatically set)
  */
 
 module.exports = {
 
     componentDidMount: function() {
         this.dispatcherRef = dis.register(this.onAction);
+        this._trackedRoom = null;
         if (this.props.room) {
-            this.showCall(this.props.room.roomId);
+            this._trackedRoom = this.props.room;
+            this.showCall(this._trackedRoom.roomId);
+        }
+        else {
+            var call = CallHandler.getAnyActiveCall();
+            if (call) {
+                console.log(
+                    "Global CallView is now tracking active call in room %s",
+                    call.roomId
+                );
+                this._trackedRoom = MatrixClientPeg.get().getRoom(call.roomId);
+                this.showCall(call.roomId);
+            }
         }
     },
 
@@ -40,26 +57,27 @@ module.exports = {
     },
 
     onAction: function(payload) {
-        // if we were given a room_id to track, don't handle anything else.
+        // don't filter out payloads for room IDs other than props.room because
-        if (payload.room_id && this.props.room && 
+        // we may be interested in the conf 1:1 room
-                this.props.room.roomId !== payload.room_id) {
+        if (payload.action !== 'call_state' || !payload.room_id) {
-            return;
-        }
-        if (payload.action !== 'call_state') {
             return;
         }
         this.showCall(payload.room_id);
     },
 
     showCall: function(roomId) {
-        var call = CallHandler.getCall(roomId);
+        var call = CallHandler.getCallForRoom(roomId);
         if (call) {
             call.setLocalVideoElement(this.getVideoView().getLocalVideoElement());
             // N.B. the remote video element is used for playback for audio for voice calls
             call.setRemoteVideoElement(this.getVideoView().getRemoteVideoElement());
         }
         if (call && call.type === "video" && call.state !== 'ended') {
-            this.getVideoView().getLocalVideoElement().style.display = "initial";
+            // if this call is a conf call, don't display local video as the
+            // conference will have us in it
+            this.getVideoView().getLocalVideoElement().style.display = (
+                call.confUserId ? "none" : "initial"
+            );
             this.getVideoView().getRemoteVideoElement().style.display = "initial";
         }
         else {

src/controllers/organisms/RoomList.js

@@ -19,11 +19,16 @@ limitations under the License.
 var React = require("react");
 var MatrixClientPeg = require("../../MatrixClientPeg");
 var RoomListSorter = require("../../RoomListSorter");
+var dis = require("../../dispatcher");
 
 var ComponentBroker = require('../../ComponentBroker');
+var ConferenceHandler = require("../../ConferenceHandler");
+var CallHandler = require("../../CallHandler");
 
 var RoomTile = ComponentBroker.get("molecules/RoomTile");
 
+var HIDE_CONFERENCE_CHANS = true;
+
 module.exports = {
     componentWillMount: function() {
         var cli = MatrixClientPeg.get();
@@ -38,7 +43,22 @@ module.exports = {
         });
     },
 
+    componentDidMount: function() {
+        this.dispatcherRef = dis.register(this.onAction);
+    },
+
+    onAction: function(payload) {
+        switch (payload.action) {
+            // listen for call state changes to prod the render method, which
+            // may hide the global CallView if the call it is tracking is dead
+            case 'call_state':
+                this._recheckCallElement(this.props.selectedRoom);
+                break;
+        }
+    },
+
     componentWillUnmount: function() {
+        dis.unregister(this.dispatcherRef);
         if (MatrixClientPeg.get()) {
             MatrixClientPeg.get().removeListener("Room", this.onRoom);
             MatrixClientPeg.get().removeListener("Room.timeline", this.onRoomTimeline);
@@ -48,6 +68,7 @@ module.exports = {
 
     componentWillReceiveProps: function(newProps) {
         this.state.activityMap[newProps.selectedRoom] = undefined;
+        this._recheckCallElement(newProps.selectedRoom);
         this.setState({
             activityMap: this.state.activityMap
         });
@@ -96,12 +117,41 @@ module.exports = {
     getRoomList: function() {
         return RoomListSorter.mostRecentActivityFirst(
             MatrixClientPeg.get().getRooms().filter(function(room) {
-                var member = room.getMember(MatrixClientPeg.get().credentials.userId);
+                var me = room.getMember(MatrixClientPeg.get().credentials.userId);
-                return member && (member.membership == "join" || member.membership == "invite");
+                var shouldShowRoom =  (
+                    me && (me.membership == "join" || me.membership == "invite")
+                );
+                // hiding conf rooms only ever toggles shouldShowRoom to false
+                if (shouldShowRoom && HIDE_CONFERENCE_CHANS) {
+                    // we want to hide the 1:1 conf<->user room and not the group chat
+                    var joinedMembers = room.getJoinedMembers();
+                    if (joinedMembers.length === 2) {
+                        var otherMember = joinedMembers.filter(function(m) {
+                            return m.userId !== me.userId
+                        })[0];
+                        if (ConferenceHandler.isConferenceUser(otherMember)) {
+                            // console.log("Hiding conference 1:1 room %s", room.roomId);
+                            shouldShowRoom = false;
+                        }
+                    }
+                }
+                return shouldShowRoom;
             })
         );
     },
 
+    _recheckCallElement: function(selectedRoomId) {
+        // if we aren't viewing a room with an ongoing call, but there is an
+        // active call, show the call element - we need to do this to make
+        // audio/video not crap out
+        var activeCall = CallHandler.getAnyActiveCall();
+        var callForRoom = CallHandler.getCallForRoom(selectedRoomId);
+        var showCall = (activeCall && !callForRoom);
+        this.setState({
+            show_call_element: showCall
+        });
+    },
+
     makeRoomTiles: function() {
         var self = this;
         return this.state.roomList.map(function(room) {
@@ -116,5 +166,5 @@ module.exports = {
                 />
             );
         });
-    },
+    }
 };

src/controllers/organisms/RoomView.js

@@ -31,7 +31,8 @@ var dis = require("../../dispatcher");
 var PAGINATE_SIZE = 20;
 var INITIAL_SIZE = 100;
 
-var ComponentBroker = require('../../ComponentBroker');
+var ConferenceHandler = require("../../ConferenceHandler");
+var CallHandler = require("../../CallHandler");
 var Notifier = ComponentBroker.get('organisms/Notifier');
 
 var tileTypes = {
@@ -62,6 +63,7 @@ module.exports = {
         MatrixClientPeg.get().on("Room.timeline", this.onRoomTimeline);
         MatrixClientPeg.get().on("Room.name", this.onRoomName);
         MatrixClientPeg.get().on("RoomMember.typing", this.onRoomMemberTyping);
+        MatrixClientPeg.get().on("RoomState.members", this.onRoomStateMember);
         this.atBottom = true;
     },
 
@@ -78,6 +80,7 @@ module.exports = {
             MatrixClientPeg.get().removeListener("Room.timeline", this.onRoomTimeline);
             MatrixClientPeg.get().removeListener("Room.name", this.onRoomName);
             MatrixClientPeg.get().removeListener("RoomMember.typing", this.onRoomMemberTyping);
+            MatrixClientPeg.get().removeListener("RoomState.members", this.onRoomStateMember);
         }
     },
 
@@ -94,15 +97,20 @@ module.exports = {
                 this.forceUpdate();
                 break;
             case 'call_state':
-                if (this.props.roomId !== payload.room_id) {
+                if (CallHandler.getCallForRoom(this.props.roomId)) {
-                    break;
+                    // Call state has changed so we may be loading video elements
-                }
+                    // which will obscure the message log.
-                // scroll to bottom
+                    // scroll to bottom
-                var messageWrapper = this.refs.messageWrapper;
+                    var messageWrapper = this.refs.messageWrapper;
-                if (messageWrapper) {
+                    if (messageWrapper) {
-                    messageWrapper = messageWrapper.getDOMNode();
+                        messageWrapper = messageWrapper.getDOMNode();
-                    messageWrapper.scrollTop = messageWrapper.scrollHeight;
+                        messageWrapper.scrollTop = messageWrapper.scrollHeight;
+                    }
                 }
+
+                // possibly remove the conf call notification if we're now in
+                // the conf
+                this._updateConfCallNotification();
                 break;
         }
     },
@@ -170,6 +178,42 @@ module.exports = {
         this.forceUpdate();
     },
 
+    onRoomStateMember: function(ev, state, member) {
+        if (member.roomId !== this.props.roomId ||
+                member.userId !== ConferenceHandler.getConferenceUserIdForRoom(member.roomId)) {
+            return;
+        }
+        this._updateConfCallNotification();
+    },
+
+    _updateConfCallNotification: function() {
+        var confMember = MatrixClientPeg.get().getRoom(this.props.roomId).getMember(
+            ConferenceHandler.getConferenceUserIdForRoom(this.props.roomId)
+        );
+
+        if (!confMember) {
+            return;
+        }
+        var confCall = CallHandler.getConferenceCall(confMember.roomId);
+
+        // A conf call notification should be displayed if there is an ongoing
+        // conf call but this cilent isn't a part of it.
+        this.setState({
+            displayConfCallNotification: (
+                (!confCall || confCall.call_state === "ended") &&
+                confMember.membership === "join"
+            )
+        });
+    },
+
+    onConferenceNotificationClick: function() {
+        dis.dispatch({
+            action: 'place_call',
+            type: "video",
+            room_id: this.props.roomId
+        });
+    },
+
     componentDidMount: function() {
         if (this.refs.messageWrapper) {
             var messageWrapper = this.refs.messageWrapper.getDOMNode();
@@ -183,6 +227,7 @@ module.exports = {
 
             this.fillSpace();
         }
+        this._updateConfCallNotification();
     },
 
     componentDidUpdate: function() {