Merge pull request #155 from matrix-org/rav/roomview_refactor

Refactor RoomView

src/component-index.js

@@ -31,9 +31,11 @@ module.exports.components['structures.login.Login'] = require('./components/stru
 module.exports.components['structures.login.PostRegistration'] = require('./components/structures/login/PostRegistration');
 module.exports.components['structures.login.Registration'] = require('./components/structures/login/Registration');
 module.exports.components['structures.MatrixChat'] = require('./components/structures/MatrixChat');
+module.exports.components['structures.MessagePanel'] = require('./components/structures/MessagePanel');
 module.exports.components['structures.RoomStatusBar'] = require('./components/structures/RoomStatusBar');
 module.exports.components['structures.RoomView'] = require('./components/structures/RoomView');
 module.exports.components['structures.ScrollPanel'] = require('./components/structures/ScrollPanel');
+module.exports.components['structures.TimelinePanel'] = require('./components/structures/TimelinePanel');
 module.exports.components['structures.UploadBar'] = require('./components/structures/UploadBar');
 module.exports.components['structures.UserSettings'] = require('./components/structures/UserSettings');
 module.exports.components['views.avatars.BaseAvatar'] = require('./components/views/avatars/BaseAvatar');

src/components/structures/MessagePanel.js

@@ -0,0 +1,267 @@
+/*
+Copyright 2016 OpenMarket Ltd
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+var React = require('react');
+var sdk = require('../../index');
+
+/* stateless UI component which builds the event tiles in the room timeline.
+ */
+module.exports = React.createClass({
+    displayName: 'MessagePanel',
+
+    propTypes: {
+        // true to give the component a 'display: none' style.
+        hidden: React.PropTypes.bool,
+
+        // the list of MatrixEvents to display
+        events: React.PropTypes.array.isRequired,
+
+        // ID of an event to highlight. If undefined, no event will be highlighted.
+        highlightedEventId: React.PropTypes.string,
+
+        // event after which we should show a read marker
+        readMarkerEventId: React.PropTypes.string,
+
+        // event after which we should show an animating disappearance of a
+        // read marker
+        readMarkerGhostEventId: React.PropTypes.string,
+
+        // the userid of our user. This is used to suppress the read marker
+        // for pending messages.
+        ourUserId: React.PropTypes.string,
+
+        // true to suppress the date at the start of the timeline
+        suppressFirstDateSeparator: React.PropTypes.bool,
+
+        // true if updates to the event list should cause the scroll panel to
+        // scroll down when we are at the bottom of the window. See ScrollPanel
+        // for more details.
+        stickyBottom: React.PropTypes.bool,
+
+        // callback to determine if a user is the magic freeswitch conference
+        // user. Takes one parameter, which is a user id. Should return true if
+        // the user is the conference user.
+        isConferenceUser: React.PropTypes.func,
+
+        // callback which is called when the panel is scrolled.
+        onScroll: React.PropTypes.func,
+
+        // callback which is called when more content is needed.
+        onFillRequest: React.PropTypes.func,
+    },
+
+    /* get the DOM node representing the given event */
+    getNodeForEventId: function(eventId) {
+        if (!this.eventNodes) {
+            return undefined;
+        }
+
+        return this.eventNodes[eventId];
+    },
+
+    /* return true if the content is fully scrolled down right now; else false.
+     */
+    isAtBottom: function() {
+        return this.refs.scrollPanel 
+            && this.refs.scrollPanel.isAtBottom();
+    },
+
+    /* get the current scroll state. See ScrollPanel.getScrollState for
+     * details.
+     *
+     * returns null if we are not mounted.
+     */
+    getScrollState: function() {
+        if (!this.refs.scrollPanel) { return null; }
+        return this.refs.scrollPanel.getScrollState();
+    },
+
+    /* jump to the bottom of the content.
+     */
+    scrollToBottom: function() {
+        if (this.refs.scrollPanel) {
+            this.refs.scrollPanel.scrollToBottom();
+        }
+    },
+
+    /* jump to the given event id.
+     *
+     * pixelOffset gives the number of pixels between the bottom of the node
+     * and the bottom of the container. If undefined, it will put the node
+     * in the middle of the container.
+     */
+    scrollToEvent: function(eventId, pixelOffset) {
+        if (this.refs.scrollPanel) {
+            this.refs.scrollPanel.scrollToToken(eventId, pixelOffset);
+        }
+    },
+
+    /* check the scroll state and send out pagination requests if necessary.
+     */
+    checkFillState: function() {
+        if (this.refs.scrollPanel) {
+            this.refs.scrollPanel.checkFillState();
+        }
+    },
+
+    _getEventTiles: function() {
+        var DateSeparator = sdk.getComponent('messages.DateSeparator');
+        var EventTile = sdk.getComponent('rooms.EventTile');
+
+        var ret = [];
+
+        var prevEvent = null; // the last event we showed
+        var ghostIndex;
+        var readMarkerIndex;
+        for (var i = 0; i < this.props.events.length; i++) {
+            var mxEv = this.props.events[i];
+
+            if (!EventTile.haveTileForEvent(mxEv)) {
+                continue;
+            }
+
+            if (this.props.isConferenceUser && mxEv.getType() === "m.room.member") {
+                if (this.props.isConferenceUser(mxEv.getSender()) ||
+                        this.props.isConferenceUser(mxEv.getStateKey())) {
+                    continue; // suppress conf user join/parts
+                }
+            }
+
+            // now we've decided whether or not to show this message,
+            // add the read up to marker if appropriate
+            // doing this here means we implicitly do not show the marker
+            // if it's at the bottom
+            // NB. it would be better to decide where the read marker was going
+            // when the state changed rather than here in the render method, but
+            // this is where we decide what messages we show so it's the only
+            // place we know whether we're at the bottom or not.
+            var mxEvSender = mxEv.sender ? mxEv.sender.userId : null;
+            if (prevEvent && prevEvent.getId() == this.props.readMarkerEventId) {
+                // suppress the read marker if the next event is sent by us; this
+                // is a nonsensical and temporary situation caused by the delay between
+                // us sending a message and receiving the synthesized receipt.
+                if (mxEvSender != this.props.ourUserId) {
+                    var hr;
+                    hr = (
+                        <hr className="mx_RoomView_myReadMarker"
+                            style={{opacity: 1, width: '99%'}} 
+                        />);
+                    readMarkerIndex = ret.length;
+                    ret.push(
+                        <li key="_readupto"
+                                className="mx_RoomView_myReadMarker_container">
+                            {hr}
+                        </li>);
+                }
+            }
+
+            // is this a continuation of the previous message?
+            var continuation = false;
+            if (prevEvent !== null) {
+                if (mxEvSender &&
+                    prevEvent.sender &&
+                    (mxEvSender === prevEvent.sender.userId) &&
+                    (mxEv.getType() == prevEvent.getType())
+                    )
+                {
+                    continuation = true;
+                }
+            }
+
+            // do we need a date separator since the last event?
+            var ts1 = mxEv.getTs();
+            if ((prevEvent == null && !this.props.suppressFirstDateSeparator) ||
+                (prevEvent != null &&
+                 new Date(prevEvent.getTs()).toDateString() 
+                     !== new Date(ts1).toDateString())) {
+                var dateSeparator = <li key={ts1}><DateSeparator key={ts1} ts={ts1}/></li>;
+                ret.push(dateSeparator);
+                continuation = false;
+            }
+
+            var last = false;
+            if (i == this.props.events.length - 1) {
+                // XXX: we might not show a tile for the last event.
+                last = true;
+            }
+
+            var eventId = mxEv.getId();
+            var highlight = (eventId == this.props.highlightedEventId);
+
+            // we can't use local echoes as scroll tokens, because their event IDs change.
+            // Local echos have a send "status".
+            var scrollToken = mxEv.status ? undefined : eventId;
+
+            ret.push(
+                <li key={eventId} 
+                        ref={this._collectEventNode.bind(this, eventId)} 
+                        data-scroll-token={scrollToken}>
+                    <EventTile mxEvent={mxEv} continuation={continuation}
+                        last={last} isSelectedEvent={highlight}/>
+                </li>
+            );
+
+            // A read up to marker has died and returned as a ghost!
+            // Lives in the dom as the ghost of the previous one while it fades away
+            if (eventId == this.props.readMarkerGhostEventId) {
+                ghostIndex = ret.length;
+            }
+
+            prevEvent = mxEv;
+        }
+
+        // splice the read marker ghost in now that we know whether the read receipt
+        // is the last element or not, because we only decide as we're going along.
+        if (readMarkerIndex === undefined && ghostIndex && ghostIndex <= ret.length) {
+            var hr;
+            hr = (
+                <hr className="mx_RoomView_myReadMarker" 
+                  style={{opacity: 1, width: '99%'}} 
+                  ref={function(n) {
+                        Velocity(n, {opacity: '0', width: '10%'},
+                                    {duration: 400, easing: 'easeInSine',
+                                     delay: 1000});
+                  }}
+            />);
+            ret.splice(ghostIndex, 0, (
+                <li key="_readuptoghost" 
+                  className="mx_RoomView_myReadMarker_container">
+                    {hr}
+                </li>
+            ));
+        }
+
+        return ret;
+    },
+
+    _collectEventNode: function(eventId, node) {
+        if (this.eventNodes == undefined) this.eventNodes = {};
+        this.eventNodes[eventId] = node;
+    },
+
+    render: function() {
+        var ScrollPanel = sdk.getComponent("structures.ScrollPanel");
+        return (
+            <ScrollPanel ref="scrollPanel" className="mx_RoomView_messagePanel"
+                    onScroll={ this.props.onScroll } 
+                    onFillRequest={ this.props.onFillRequest }
+                    style={ this.props.hidden ? { display: 'none' } : {} }
+                    stickyBottom={ this.props.stickyBottom }>
+                {this._getEventTiles()}
+            </ScrollPanel>
+        );
+    },
+});

src/components/structures/RoomView.js

@@ -19,14 +19,12 @@ limitations under the License.
 //  - Search results component
 //  - Drag and drop
 //  - File uploading - uploadFile()
-//  - Timeline component (alllll the logic in getEventTiles())
 
 var React = require("react");
 var ReactDOM = require("react-dom");
 var q = require("q");
 var classNames = require("classnames");
 var Matrix = require("matrix-js-sdk");
-var EventTimeline = Matrix.EventTimeline;
 
 var MatrixClientPeg = require("../../MatrixClientPeg");
 var ContentMessages = require("../../ContentMessages");
@@ -42,14 +40,9 @@ var dis = require("../../dispatcher");
 var Tinter = require("../../Tinter");
 var rate_limited_func = require('../../ratelimitedfunc');
 
-var PAGINATE_SIZE = 20;
+var DEBUG = false;
-var INITIAL_SIZE = 20;
-var SEND_READ_RECEIPT_DELAY = 2000;
-var TIMELINE_CAP = 1000; // the most events to show in a timeline
 
-var DEBUG_SCROLL = false;
+if (DEBUG) {
-
-if (DEBUG_SCROLL) {
     // using bind means that we get to keep useful line numbers in the console
     var debuglog = console.log.bind(console);
 } else {
@@ -77,17 +70,11 @@ module.exports = React.createClass({
         highlightedEventId: React.PropTypes.string,
     },
 
-    /* properties in RoomView objects include:
-     *
-     * eventNodes: a map from event id to DOM node representing that event
-     */
     getInitialState: function() {
         var room = this.props.roomId ? MatrixClientPeg.get().getRoom(this.props.roomId) : null;
         return {
             room: room,
-            events: [],
+            roomLoading: !room,
-            canBackPaginate: true,
-            paginating: room != null,
             editingRoomSettings: false,
             uploadingRoomSettings: false,
             numUnreadMessages: 0,
@@ -96,11 +83,8 @@ module.exports = React.createClass({
             searchResults: null,
             hasUnsentMessages: this._hasUnsentMessages(room),
             callState: null,
-            timelineLoading: true, // track whether our room timeline is loading
             guestsCanJoin: false,
             canPeek: false,
-            readMarkerEventId: room ? room.getEventReadUpTo(MatrixClientPeg.get().credentials.userId) : null,
-            readMarkerGhostEventId: undefined,
 
             // this is true if we are fully scrolled-down, and are looking at
             // the end of the live timeline. It has the effect of hiding the
@@ -110,13 +94,11 @@ module.exports = React.createClass({
     },
 
     componentWillMount: function() {
-        this.last_rr_sent_event_id = undefined;
         this.dispatcherRef = dis.register(this.onAction);
         MatrixClientPeg.get().on("Room", this.onRoom);
         MatrixClientPeg.get().on("Room.timeline", this.onRoomTimeline);
         MatrixClientPeg.get().on("Room.name", this.onRoomName);
         MatrixClientPeg.get().on("Room.accountData", this.onRoomAccountData);
-        MatrixClientPeg.get().on("Room.receipt", this.onRoomReceipt);
         MatrixClientPeg.get().on("RoomMember.typing", this.onRoomMemberTyping);
         MatrixClientPeg.get().on("RoomState.members", this.onRoomStateMember);
         // xchat-style tab complete, add a colon if tab
@@ -131,13 +113,6 @@ module.exports = React.createClass({
         });
 
 
-        // to make the timeline load work correctly, build up a chain of promises which
-        // take us through the necessary steps.
-
-        // First of all, we may need to load the room. Construct a promise
-        // which resolves to the Room object.
-        var roomProm;
-
         // if this is an unknown room then we're in one of three states:
         // - This is a room we can peek into (search engine) (we can /peek)
         // - This is a room we can publicly join or were invited to. (we can /join)
@@ -148,93 +123,28 @@ module.exports = React.createClass({
         if (!this.state.room) {
             console.log("Attempting to peek into room %s", this.props.roomId);
 
-            roomProm = MatrixClientPeg.get().peekInRoom(this.props.roomId).then((room) => {
+            MatrixClientPeg.get().peekInRoom(this.props.roomId).then((room) => {
                 this.setState({
-                    room: room
+                    room: room,
+                    roomLoading: false,
                 });
-                return room;
+                this._onRoomLoaded(room);
-            });
+            }, (err) => {
-        } else {
+                // This won't necessarily be a MatrixError, but we duck-type
-            roomProm = q(this.state.room);
+                // here and say if it's got an 'errcode' key with the right value,
-        }
+                // it means we can't peek.
-
+                if (err.errcode == "M_GUEST_ACCESS_FORBIDDEN") {
-        // Next, load the timeline.
+                    // This is fine: the room just isn't peekable (we assume).
-        roomProm.then((room) => {
+                    this.setState({
-            this._calculatePeekRules(room);
+                        roomLoading: false,
-            return this._initTimeline(this.props);
+                    });
-        }).catch((err) => {
-            // This won't necessarily be a MatrixError, but we duck-type
-            // here and say if it's got an 'errcode' key with the right value,
-            // it means we can't peek.
-            if (err.errcode == "M_GUEST_ACCESS_FORBIDDEN") {
-                // This is fine: the room just isn't peekable (we assume).
-                this.setState({
-                    timelineLoading: false,
-                });
-            } else {
-                throw err;
-            }
-        }).done();
-    },
-
-    _initTimeline: function(props) {
-        var initialEvent = props.eventId;
-        var pixelOffset = props.eventPixelOffset;
-        return this._loadTimeline(initialEvent, pixelOffset);
-    },
-
-    /**
-     * (re)-load the event timeline, and initialise the scroll state, centered
-     * around the given event.
-     *
-     * @param {string?}  eventId the event to focus on. If undefined, will
-     *    scroll to the bottom of the room.
-     *
-     * @param {number?} pixelOffset   offset to position the given event at
-     *    (pixels from the bottom of the view). If undefined, will put the
-     *    event in the middle of the view.
-     *
-     * returns a promise which will resolve when the load completes.
-     */
-    _loadTimeline: function(eventId, pixelOffset) {
-        // TODO: we could optimise this, by not resetting the window if the
-        // event is in the current window (though it's not obvious how we can
-        // tell if the current window is on the live event stream)
-
-        this.setState({
-            events: [],
-            searchResults: null, // we may have arrived here by clicking on a
-                                 // search result. Hide the results.
-            timelineLoading: true,
-        });
-
-        this._timelineWindow = new Matrix.TimelineWindow(
-            MatrixClientPeg.get(), this.state.room,
-            {windowLimit: TIMELINE_CAP});
-
-        return this._timelineWindow.load(eventId, INITIAL_SIZE).then(() => {
-            debuglog("RoomView: timeline loaded");
-            this._onTimelineUpdated(true);
-        }).finally(() => {
-            this.setState({
-                timelineLoading: false,
-            }, () => {
-                // initialise the scroll state of the message panel
-                if (!this.refs.messagePanel) {
-                    // this shouldn't happen.
-                    console.log("can't initialise scroll state because " +
-                                "messagePanel didn't load");
-                    return;
-                }
-                if (eventId) {
-                    this.refs.messagePanel.scrollToToken(eventId, pixelOffset);
                 } else {
-                    this.refs.messagePanel.scrollToBottom();
+                    throw err;
                 }
-
+            }).done();
-                this.sendReadReceipt();
+        } else {
-            });
+            this._onRoomLoaded(this.state.room);
-        });
+        }
     },
 
     componentWillUnmount: function() {
@@ -261,7 +171,6 @@ module.exports = React.createClass({
             MatrixClientPeg.get().removeListener("Room.timeline", this.onRoomTimeline);
             MatrixClientPeg.get().removeListener("Room.name", this.onRoomName);
             MatrixClientPeg.get().removeListener("Room.accountData", this.onRoomAccountData);
-            MatrixClientPeg.get().removeListener("Room.receipt", this.onRoomReceipt);
             MatrixClientPeg.get().removeListener("RoomMember.typing", this.onRoomMemberTyping);
             MatrixClientPeg.get().removeListener("RoomState.members", this.onRoomStateMember);
         }
@@ -316,15 +225,6 @@ module.exports = React.createClass({
                     callState: callState
                 });
 
-                break;
-            case 'user_activity':
-            case 'user_activity_end':
-                // we could treat user_activity_end differently and not
-                // send receipts for messages that have arrived between
-                // the actual user activity and the time they stopped
-                // being active, but let's see if this is actually
-                // necessary.
-                this.sendReadReceipt();
                 break;
         }
     },
@@ -335,9 +235,8 @@ module.exports = React.createClass({
         }
 
         if (newProps.eventId != this.props.eventId) {
-            console.log("RoomView switching to eventId " + newProps.eventId +
+            // when we change focussed event id, hide the search results.
-                        " (was " + this.props.eventId + ")");
+            this.setState({searchResults: null});
-            return this._initTimeline(newProps);
         }
     },
 
@@ -366,15 +265,12 @@ module.exports = React.createClass({
                 });
             }
         }
+    },
 
-        // tell the messagepanel to go paginate itself. This in turn will cause
+    // called when state.room is first initialised (either at initial load,
-        // onMessageListFillRequest to be called, which will call
+    // after a successful peek, or after we join the room).
-        // _onTimelineUpdated, which will update the state with the new event -
+    _onRoomLoaded: function(room) {
-        // so there is no need update the state here.
+        this._calculatePeekRules(room);
-        //
-        if (this.refs.messagePanel) {
-            this.refs.messagePanel.checkFillState();
-        }
     },
 
     _calculatePeekRules: function(room) {
@@ -399,19 +295,25 @@ module.exports = React.createClass({
         // set it in our state and start using it (ie. init the timeline)
         // This will happen if we start off viewing a room we're not joined,
         // then join it whilst RoomView is looking at that room.
-        if (room.roomId == this.props.roomId) {
+        if (room.roomId == this.props.roomId && !this.state.room) {
             this.setState({
                 room: room
             });
-            this._initTimeline(this.props).done();
+            this._onRoomLoaded(room);
         }
     },
 
     onRoomName: function(room) {
-        if (room.roomId == this.props.roomId) {
+        // NB don't set state.room here.
-            this.setState({
+        //
-                room: room
+        // When peeking, this event lands *before* the timeline is correctly
-            });
+        // synced; if we set state.room here, the TimelinePanel will be
+        // instantiated, and it will initialise its scroll state, with *no
+        // events*. In short, the scroll state will be all messed up.
+        //
+        // There's no need to set state.room here anyway.
+        if (room.roomId == this.props.roomId) { 
+            this.forceUpdate();
         }
     },
 
@@ -438,38 +340,6 @@ module.exports = React.createClass({
         }
     },
 
-    onRoomReceipt: function(receiptEvent, room) {
-        if (room.roomId == this.props.roomId) {
-            var readMarkerEventId = this.state.room.getEventReadUpTo(MatrixClientPeg.get().credentials.userId);
-            var readMarkerGhostEventId = this.state.readMarkerGhostEventId;
-            if (this.state.readMarkerEventId !== undefined && this.state.readMarkerEventId != readMarkerEventId) {
-                readMarkerGhostEventId = this.state.readMarkerEventId;
-            }
-
-
-            // if the event after the one referenced in the read receipt if sent by us, do nothing since
-            // this is a temporary period before the synthesized receipt for our own message arrives
-            var readMarkerGhostEventIndex;
-            for (var i = 0; i < this.state.events.length; ++i) {
-                if (this.state.events[i].getId() == readMarkerGhostEventId) {
-                    readMarkerGhostEventIndex = i;
-                    break;
-                }
-            }
-            if (readMarkerGhostEventIndex + 1 < this.state.events.length) {
-                var nextEvent = this.state.events[readMarkerGhostEventIndex + 1];
-                if (nextEvent.sender && nextEvent.sender.userId == MatrixClientPeg.get().credentials.userId) {
-                    readMarkerGhostEventId = undefined;
-                }
-            }
-
-            this.setState({
-                readMarkerEventId: readMarkerEventId,
-                readMarkerGhostEventId: readMarkerGhostEventId,
-            });
-        }
-    },
-
     onRoomMemberTyping: function(ev, member) {
         this.forceUpdate();
     },
@@ -537,10 +407,6 @@ module.exports = React.createClass({
     },
 
     componentDidMount: function() {
-        if (this.refs.messagePanel) {
-            this._initialiseMessagePanel();
-        }
-
         var call = CallHandler.getCallForRoom(this.props.roomId);
         var callState = call ? call.call_state : "ended";
         this.setState({
@@ -585,40 +451,6 @@ module.exports = React.createClass({
         );
     }, 500),
 
-    _initialiseMessagePanel: function() {
-        var messagePanel = ReactDOM.findDOMNode(this.refs.messagePanel);
-        this.refs.messagePanel.initialised = true;
-        this.updateTint();
-    },
-
-    componentDidUpdate: function() {
-        // we need to initialise the messagepanel if we've just joined the
-        // room. TODO: we really really ought to factor out messagepanel to a
-        // separate component to avoid this ridiculous dance.
-        if (!this.refs.messagePanel) return;
-
-        if (!this.refs.messagePanel.initialised) {
-            this._initialiseMessagePanel();
-        }
-    },
-
-    _onTimelineUpdated: function(gotResults) {
-        // we might have switched rooms since the load started - just bin
-        // the results if so.
-        if (this.unmounted) return;
-
-        this.setState({
-            paginating: false,
-        });
-
-        if (gotResults) {
-            this.setState({
-                events: this._timelineWindow.getEvents(),
-                canBackPaginate: this._timelineWindow.canPaginate(EventTimeline.BACKWARDS),
-            });
-        }
-    },
-
     onSearchResultsFillRequest: function(backwards) {
         if (!backwards)
             return q(false);
@@ -634,23 +466,6 @@ module.exports = React.createClass({
         }
     },
 
-    // set off a pagination request.
-    onMessageListFillRequest: function(backwards) {
-        var dir = backwards ? EventTimeline.BACKWARDS : EventTimeline.FORWARDS;
-        if(!this._timelineWindow.canPaginate(dir)) {
-            debuglog("RoomView: can't paginate at this time; backwards:"+backwards);
-            return q(false);
-        }
-        this.setState({paginating: true});
-
-        debuglog("RoomView: Initiating paginate; backwards:"+backwards);
-        return this._timelineWindow.paginate(dir, PAGINATE_SIZE).then((r) => {
-            debuglog("RoomView: paginate complete backwards:"+backwards+"; success:"+r);
-            this._onTimelineUpdated(r);
-            return r;
-        });
-    },
-
     onResendAllClick: function() {
         var eventsToResend = this._getUnsentMessages(this.state.room);
         eventsToResend.forEach(function(event) {
@@ -727,19 +542,16 @@ module.exports = React.createClass({
     },
 
     onMessageListScroll: function(ev) {
-        if (this.refs.messagePanel.isAtBottom() &&
+        if (this.refs.messagePanel.isAtEndOfLiveTimeline()) {
-                !this._timelineWindow.canPaginate(EventTimeline.FORWARDS)) {
+            this.setState({
-            if (this.state.numUnreadMessages != 0) {
+                numUnreadMessages: 0,
-                this.setState({ numUnreadMessages: 0 });
+                atEndOfLiveTimeline: true,
-            }
+            });
-            if (!this.state.atEndOfLiveTimeline) {
-                this.setState({ atEndOfLiveTimeline: true });
-            }
         }
         else {
-            if (this.state.atEndOfLiveTimeline) {
+            this.setState({
-                this.setState({ atEndOfLiveTimeline: false });
+                atEndOfLiveTimeline: false,
-            }
+            });
         }
     },
 
@@ -954,207 +766,6 @@ module.exports = React.createClass({
         return ret;
     },
 
-    getEventTiles: function() {
-        var DateSeparator = sdk.getComponent('messages.DateSeparator');
-
-        var ret = [];
-        var count = 0;
-
-        var EventTile = sdk.getComponent('rooms.EventTile');
-
-        var prevEvent = null; // the last event we showed
-        var ghostIndex;
-        var readMarkerIndex;
-        for (var i = 0; i < this.state.events.length; i++) {
-            var mxEv = this.state.events[i];
-
-            if (!EventTile.haveTileForEvent(mxEv)) {
-                continue;
-            }
-            if (this.props.ConferenceHandler && mxEv.getType() === "m.room.member") {
-                if (this.props.ConferenceHandler.isConferenceUser(mxEv.getSender()) ||
-                        this.props.ConferenceHandler.isConferenceUser(mxEv.getStateKey())) {
-                    continue; // suppress conf user join/parts
-                }
-            }
-
-            // now we've decided whether or not to show this message,
-            // add the read up to marker if appropriate
-            // doing this here means we implicitly do not show the marker
-            // if it's at the bottom
-            // NB. it would be better to decide where the read marker was going
-            // when the state changed rather than here in the render method, but
-            // this is where we decide what messages we show so it's the only
-            // place we know whether we're at the bottom or not.
-            var self = this;
-            var mxEvSender = mxEv.sender ? mxEv.sender.userId : null;
-            if (prevEvent && prevEvent.getId() == this.state.readMarkerEventId && mxEvSender != MatrixClientPeg.get().credentials.userId) {
-                var hr;
-                hr = (<hr className="mx_RoomView_myReadMarker" style={{opacity: 1, width: '99%'}} ref={function(n) {
-                    self.readMarkerNode = n;
-                }} />);
-                readMarkerIndex = ret.length;
-                ret.push(<li key="_readupto" className="mx_RoomView_myReadMarker_container">{hr}</li>);
-            }
-
-            // is this a continuation of the previous message?
-            var continuation = false;
-            if (prevEvent !== null) {
-                if (mxEv.sender &&
-                    prevEvent.sender &&
-                    (mxEv.sender.userId === prevEvent.sender.userId) &&
-                    (mxEv.getType() == prevEvent.getType())
-                    )
-                {
-                    continuation = true;
-                }
-            }
-
-            // do we need a date separator since the last event?
-            var ts1 = mxEv.getTs();
-            if ((prevEvent == null && !this.state.canBackPaginate) ||
-                (prevEvent != null &&
-                 new Date(prevEvent.getTs()).toDateString() !== new Date(ts1).toDateString())) {
-                var dateSeparator = <li key={ts1}><DateSeparator key={ts1} ts={ts1}/></li>;
-                ret.push(dateSeparator);
-                continuation = false;
-            }
-
-            var last = false;
-            if (i == this.state.events.length - 1) {
-                // XXX: we might not show a tile for the last event.
-                last = true;
-            }
-
-            var eventId = mxEv.getId();
-            var highlight = (eventId == this.props.highlightedEventId);
-
-            // we can't use local echoes as scroll tokens, because their event IDs change.
-            // Local echos have a send "status".
-            var scrollToken = mxEv.status ? undefined : eventId;
-
-            ret.push(
-                <li key={eventId} 
-                        ref={this._collectEventNode.bind(this, eventId)} 
-                        data-scroll-token={scrollToken}>
-                    <EventTile mxEvent={mxEv} continuation={continuation}
-                        last={last} isSelectedEvent={highlight}/>
-                </li>
-            );
-
-            // A read up to marker has died and returned as a ghost!
-            // Lives in the dom as the ghost of the previous one while it fades away
-            if (eventId == this.state.readMarkerGhostEventId) {
-                ghostIndex = ret.length;
-            }
-
-            prevEvent = mxEv;
-        }
-
-        // splice the read marker ghost in now that we know whether the read receipt
-        // is the last element or not, because we only decide as we're going along.
-        if (readMarkerIndex === undefined && ghostIndex && ghostIndex <= ret.length) {
-            var hr;
-            hr = (<hr className="mx_RoomView_myReadMarker" style={{opacity: 1, width: '99%'}} ref={function(n) {
-                Velocity(n, {opacity: '0', width: '10%'}, {duration: 400, easing: 'easeInSine', delay: 1000, complete: function() {
-                    if (!self.unmounted) self.setState({readMarkerGhostEventId: undefined});
-                }});
-            }} />);
-            ret.splice(ghostIndex, 0, (
-                <li key="_readuptoghost" className="mx_RoomView_myReadMarker_container">{hr}</li>
-            ));
-        }
-
-        return ret;
-    },
-
-    _collectEventNode: function(eventId, node) {
-        if (this.eventNodes == undefined) this.eventNodes = {};
-        this.eventNodes[eventId] = node;
-    },
-
-    _indexForEventId(evId) {
-        for (var i = 0; i < this.state.events.length; ++i) {
-            if (evId == this.state.events[i].getId()) {
-                return i;
-            }
-        }
-        return null;
-    },
-
-    sendReadReceipt: function() {
-        if (!this.state.room) return;
-        if (!this.refs.messagePanel) return;
-
-        // we don't want to see our RR marker dropping down as we scroll
-        // through old history. For now, do this just by leaving the RR where
-        // it is until we hit the bottom of the room, though ultimately we
-        // probably want to keep sending RR, but hide the RR until we reach
-        // the bottom of the room again, or something.
-        if (!this.state.atEndOfLiveTimeline) return;
-
-        var currentReadUpToEventId = this.state.room.getEventReadUpTo(MatrixClientPeg.get().credentials.userId);
-        var currentReadUpToEventIndex = this._indexForEventId(currentReadUpToEventId);
-
-        // We want to avoid sending out read receipts when we are looking at
-        // events in the past which are before the latest RR.
-        //
-        // For now, let's apply a heuristic: if (a) the event corresponding to
-        // the latest RR (either from the server, or sent by ourselves) doesn't
-        // appear in our timeline, and (b) we could forward-paginate the event
-        // timeline, then don't send any more RRs.
-        //
-        // This isn't watertight, as we could be looking at a section of
-        // timeline which is *after* the latest RR (so we should actually send
-        // RRs) - but that is a bit of a niche case. It will sort itself out when
-        // the user eventually hits the live timeline.
-        //
-        if (currentReadUpToEventId && currentReadUpToEventIndex === null &&
-                this._timelineWindow.canPaginate(EventTimeline.FORWARDS)) {
-            return;
-        }
-
-        var lastReadEventIndex = this._getLastDisplayedEventIndexIgnoringOwn();
-        if (lastReadEventIndex === null) return;
-
-        var lastReadEvent = this.state.events[lastReadEventIndex];
-
-        // we also remember the last read receipt we sent to avoid spamming the same one at the server repeatedly
-        if (lastReadEventIndex > currentReadUpToEventIndex && this.last_rr_sent_event_id != lastReadEvent.getId()) {
-            this.last_rr_sent_event_id = lastReadEvent.getId();
-            MatrixClientPeg.get().sendReadReceipt(lastReadEvent).catch(() => {
-                // it failed, so allow retries next time the user is active
-                this.last_rr_sent_event_id = undefined;
-            });
-        }
-    },
-
-    _getLastDisplayedEventIndexIgnoringOwn: function() {
-        if (this.eventNodes === undefined) return null;
-
-        var messageWrapper = this.refs.messagePanel;
-        if (messageWrapper === undefined) return null;
-        var wrapperRect = ReactDOM.findDOMNode(messageWrapper).getBoundingClientRect();
-
-        for (var i = this.state.events.length-1; i >= 0; --i) {
-            var ev = this.state.events[i];
-
-            if (ev.sender && ev.sender.userId == MatrixClientPeg.get().credentials.userId) {
-                continue;
-            }
-
-            var node = this.eventNodes[ev.getId()];
-            if (!node) continue;
-
-            var boundingRect = node.getBoundingClientRect();
-
-            if (boundingRect.bottom < wrapperRect.bottom) {
-                return i;
-            }
-        }
-        return null;
-    },
-
     onSettingsClick: function() {
         this.showSettings(true);
     },
@@ -1259,18 +870,7 @@ module.exports = React.createClass({
 
     // jump down to the bottom of this room, where new events are arriving
     jumpToLiveTimeline: function() {
-        // if we can't forward-paginate the existing timeline, then there
+        this.refs.messagePanel.jumpToLiveTimeline();
-        // is no point reloading it - just jump straight to the bottom.
-        //
-        // Otherwise, reload the timeline rather than trying to paginate
-        // through all of space-time.
-        if (this._timelineWindow.canPaginate(EventTimeline.FORWARDS)) {
-            this._loadTimeline();
-        } else {
-            if (this.refs.messagePanel) {
-                this.refs.messagePanel.scrollToBottom();
-            }
-        }
     },
 
     // get the current scroll position of the room, so that it can be
@@ -1416,10 +1016,11 @@ module.exports = React.createClass({
         var TintableSvg = sdk.getComponent("elements.TintableSvg");
         var RoomPreviewBar = sdk.getComponent("rooms.RoomPreviewBar");
         var Loader = sdk.getComponent("elements.Spinner");
+        var TimelinePanel = sdk.getComponent("structures.TimelinePanel");
 
-        if (!this._timelineWindow) {
+        if (!this.state.room) {
             if (this.props.roomId) {
-                if (this.state.timelineLoading) {
+                if (this.state.roomLoading) {
                     return (
                         <div className="mx_RoomView">
                             <Loader />
@@ -1501,7 +1102,6 @@ module.exports = React.createClass({
 
         var scrollheader_classes = classNames({
             mx_RoomView_scrollheader: true,
-            loading: this.state.paginating
         });
 
         var statusBar;
@@ -1656,47 +1256,21 @@ module.exports = React.createClass({
             hideMessagePanel = true;
         }
 
-        var messagePanel;
+        var messagePanel = (
-
+            <TimelinePanel ref={(r) => {
-        // just show a spinner while the timeline loads.
+                        this.refs.messagePanel = r;
-        //
+                        this.updateTint();
-        // put it in a div of the right class (mx_RoomView_messagePanel) so
+                }}
-        // that the order in the roomview flexbox is correct, and
+                room={this.state.room}
-        // mx_RoomView_messageListWrapper to position the inner div in the
+                hidden={hideMessagePanel}
-        // right place.
+                highlightedEventId={this.props.highlightedEventId}
-        //
+                eventId={this.props.eventId}
-        // Note that the click-on-search-result functionality relies on the
+                eventPixelOffset={this.props.eventPixelOffset}
-        // fact that the messagePanel is hidden while the timeline reloads,
+                isConferenceUser={this.props.ConferenceHandler ?
-        // but that the RoomHeader (complete with search term) continues to
+                                  this.props.ConferenceHandler.isConferenceUser :
-        // exist.
+                                  null }
-        if (this.state.timelineLoading) {
+                onScroll={ this.onMessageListScroll }
-            messagePanel = (
+            />);
-                    <div className="mx_RoomView_messagePanel mx_RoomView_messageListWrapper">
-                        <Loader />
-                    </div>
-            );
-        } else {
-            // give the messagepanel a stickybottom if we're at the end of the
-            // live timeline, so that the arrival of new events triggers a
-            // scroll.
-            //
-            // Make sure that stickyBottom is *false* if we can paginate
-            // forwards, otherwise if somebody hits the bottom of the loaded
-            // events when viewing historical messages, we get stuck in a loop
-            // of paginating our way through the entire history of the room.
-            var stickyBottom = !this._timelineWindow.canPaginate(EventTimeline.FORWARDS);
-
-            messagePanel = (
-                <ScrollPanel ref="messagePanel" className="mx_RoomView_messagePanel"
-                        onScroll={ this.onMessageListScroll } 
-                        onFillRequest={ this.onMessageListFillRequest }
-                        style={ hideMessagePanel ? { display: 'none' } : {} }
-                        stickyBottom={ stickyBottom }>
-                    <li className={scrollheader_classes}></li>
-                    {this.getEventTiles()}
-                </ScrollPanel>
-            );
-        }
 
         return (
             <div className={ "mx_RoomView" + (inCall ? " mx_RoomView_inCall" : "") } ref="roomView">

src/components/structures/TimelinePanel.js

@@ -0,0 +1,450 @@
+/*
+Copyright 2016 OpenMarket Ltd
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+var React = require('react');
+var ReactDOM = require("react-dom");
+var q = require("q");
+
+var Matrix = require("matrix-js-sdk");
+var EventTimeline = Matrix.EventTimeline;
+
+var sdk = require('../../index');
+var MatrixClientPeg = require("../../MatrixClientPeg");
+var dis = require("../../dispatcher");
+
+var PAGINATE_SIZE = 20;
+var INITIAL_SIZE = 20;
+var TIMELINE_CAP = 1000; // the most events to show in a timeline
+
+var DEBUG = false;
+
+if (DEBUG) {
+    // using bind means that we get to keep useful line numbers in the console
+    var debuglog = console.log.bind(console);
+} else {
+    var debuglog = function () {};
+}
+
+/*
+ * Component which shows the event timeline in a room view.
+ *
+ * Also responsible for handling and sending read receipts.
+ */
+module.exports = React.createClass({
+    displayName: 'TimelinePanel',
+
+    propTypes: {
+        // The js-sdk Room object for the room whose timeline we are
+        // representing.
+        room: React.PropTypes.object.isRequired,
+
+        // true to give the component a 'display: none' style.
+        hidden: React.PropTypes.bool,
+
+        // ID of an event to highlight. If undefined, no event will be highlighted.
+        // typically this will be either 'eventId' or undefined.
+        highlightedEventId: React.PropTypes.string,
+
+        // id of an event to jump to. If not given, will go to the end of the
+        // live timeline.
+        eventId: React.PropTypes.string,
+
+        // where to position the event given by eventId, in pixels from the
+        // bottom of the viewport. If not given, will try to put the event in the
+        // middle of the viewprt.
+        eventPixelOffset: React.PropTypes.number,
+
+        // callback to determine if a user is the magic freeswitch conference
+        // user. Takes one parameter, which is a user id. Should return true if
+        // the user is the conference user.
+        isConferenceUser: React.PropTypes.func,
+
+        // callback which is called when the panel is scrolled.
+        onScroll: React.PropTypes.func,
+    },
+
+    getInitialState: function() {
+        return {
+            events: [],
+            timelineLoading: true, // track whether our room timeline is loading
+            canBackPaginate: true,
+            readMarkerEventId: this._getCurrentReadReceipt(),
+            readMarkerGhostEventId: null,
+        };
+    },
+
+    componentWillMount: function() {
+        debuglog("TimelinePanel: mounting");
+
+        this.last_rr_sent_event_id = undefined;
+        this.dispatcherRef = dis.register(this.onAction);
+        MatrixClientPeg.get().on("Room.timeline", this.onRoomTimeline);
+        MatrixClientPeg.get().on("Room.receipt", this.onRoomReceipt);
+
+        this._initTimeline(this.props);
+    },
+
+    componentWillReceiveProps: function(newProps) {
+        if (newProps.room !== this.props.room) {
+            throw new Error("changing room on a TimelinePanel is not supported");
+        }
+
+        if (newProps.eventId != this.props.eventId) {
+            console.log("TimelinePanel switching to eventId " + newProps.eventId +
+                        " (was " + this.props.eventId + ")");
+            return this._initTimeline(newProps);
+        }
+    },
+
+    componentWillUnmount: function() {
+        // set a boolean to say we've been unmounted, which any pending
+        // promises can use to throw away their results.
+        //
+        // (We could use isMounted, but facebook have deprecated that.)
+        this.unmounted = true;
+
+        dis.unregister(this.dispatcherRef);
+        MatrixClientPeg.get().removeListener("Room.timeline", this.onRoomTimeline);
+        MatrixClientPeg.get().removeListener("Room.receipt", this.onRoomReceipt);
+    },
+
+    // set off a pagination request.
+    onMessageListFillRequest: function(backwards) {
+        var dir = backwards ? EventTimeline.BACKWARDS : EventTimeline.FORWARDS;
+        if(!this._timelineWindow.canPaginate(dir)) {
+            debuglog("TimelinePanel: can't paginate at this time; backwards:"+backwards);
+            return q(false);
+        }
+        debuglog("TimelinePanel: Initiating paginate; backwards:"+backwards);
+        return this._timelineWindow.paginate(dir, PAGINATE_SIZE).then((r) => {
+            debuglog("TimelinePanel: paginate complete backwards:"+backwards+"; success:"+r);
+            this._onTimelineUpdated(r);
+            return r;
+        });
+    },
+
+    onAction: function(payload) {
+        switch (payload.action) {
+            case 'user_activity':
+            case 'user_activity_end':
+                // we could treat user_activity_end differently and not
+                // send receipts for messages that have arrived between
+                // the actual user activity and the time they stopped
+                // being active, but let's see if this is actually
+                // necessary.
+                this.sendReadReceipt();
+                break;
+        }
+    },
+
+    onRoomTimeline: function(ev, room, toStartOfTimeline, removed, data) {
+        // ignore events for other rooms
+        if (room !== this.props.room) return;
+
+        // ignore anything but real-time updates at the end of the room:
+        // updates from pagination will happen when the paginate completes.
+        if (toStartOfTimeline || !data || !data.liveEvent) return;
+
+        // tell the messagepanel to go paginate itself. This in turn will cause
+        // onMessageListFillRequest to be called, which will call
+        // _onTimelineUpdated, which will update the state with the new event -
+        // so there is no need update the state here.
+        //
+        if (this.refs.messagePanel) {
+            this.refs.messagePanel.checkFillState();
+        }
+    },
+
+    onRoomReceipt: function(receiptEvent, room) {
+        if (room !== this.props.room)
+            return;
+
+        // the received event may or may not be for our user; but it turns out
+        // to be easier to do the processing anyway than to figure out if it
+        // is.
+        var oldReadMarker = this.state.readMarkerEventId;
+        var newReadMarker = this._getCurrentReadReceipt();
+
+        if (newReadMarker == oldReadMarker) {
+            return;
+        }
+
+        // suppress the animation when moving forward over an event which was sent
+        // by us; the original RM will have been suppressed so we don't want to show
+        // the animation either.
+        var oldReadMarkerIndex = this._indexForEventId(oldReadMarker);
+        if (oldReadMarkerIndex + 1 < this.state.events.length) {
+            var myUserId = MatrixClientPeg.get().credentials.userId;
+            var nextEvent = this.state.events[oldReadMarkerIndex + 1];
+            if (nextEvent.sender && nextEvent.sender.userId == myUserId) {
+                oldReadMarker = undefined;
+            }
+        }
+
+        this.setState({
+            readMarkerEventId: newReadMarker,
+            readMarkerGhostEventId: oldReadMarker,
+        });
+    },
+
+    sendReadReceipt: function() {
+        if (!this.refs.messagePanel) return;
+
+        var currentReadUpToEventId = this._getCurrentReadReceipt();
+        var currentReadUpToEventIndex = this._indexForEventId(currentReadUpToEventId);
+
+        // We want to avoid sending out read receipts when we are looking at
+        // events in the past which are before the latest RR.
+        //
+        // For now, let's apply a heuristic: if (a) the event corresponding to
+        // the latest RR (either from the server, or sent by ourselves) doesn't
+        // appear in our timeline, and (b) we could forward-paginate the event
+        // timeline, then don't send any more RRs.
+        //
+        // This isn't watertight, as we could be looking at a section of
+        // timeline which is *after* the latest RR (so we should actually send
+        // RRs) - but that is a bit of a niche case. It will sort itself out when
+        // the user eventually hits the live timeline.
+        //
+        if (currentReadUpToEventId && currentReadUpToEventIndex === null &&
+                this._timelineWindow.canPaginate(EventTimeline.FORWARDS)) {
+            return;
+        }
+
+        var lastReadEventIndex = this._getLastDisplayedEventIndexIgnoringOwn();
+        if (lastReadEventIndex === null) return;
+
+        var lastReadEvent = this.state.events[lastReadEventIndex];
+
+        // we also remember the last read receipt we sent to avoid spamming the
+        // same one at the server repeatedly
+        if (lastReadEventIndex > currentReadUpToEventIndex
+                && this.last_rr_sent_event_id != lastReadEvent.getId()) {
+            this.last_rr_sent_event_id = lastReadEvent.getId();
+            MatrixClientPeg.get().sendReadReceipt(lastReadEvent).catch(() => {
+                // it failed, so allow retries next time the user is active
+                this.last_rr_sent_event_id = undefined;
+            });
+        }
+    },
+
+    /* jump down to the bottom of this room, where new events are arriving
+     */
+    jumpToLiveTimeline: function() {
+        // if we can't forward-paginate the existing timeline, then there
+        // is no point reloading it - just jump straight to the bottom.
+        //
+        // Otherwise, reload the timeline rather than trying to paginate
+        // through all of space-time.
+        if (this._timelineWindow.canPaginate(EventTimeline.FORWARDS)) {
+            this._loadTimeline();
+        } else {
+            if (this.refs.messagePanel) {
+                this.refs.messagePanel.scrollToBottom();
+            }
+        }
+    },
+
+    /* return true if the content is fully scrolled down and we are
+     * at the end of the live timeline.
+     */
+    isAtEndOfLiveTimeline: function() {
+        return this.refs.messagePanel
+            && this.refs.messagePanel.isAtBottom()
+            && this._timelineWindow
+            && !this._timelineWindow.canPaginate(EventTimeline.FORWARDS);
+    },
+
+
+    /* get the current scroll state. See ScrollPanel.getScrollState for
+     * details.
+     *
+     * returns null if we are not mounted.
+     */
+    getScrollState: function() {
+        if (!this.refs.messagePanel) { return null; }
+        return this.refs.messagePanel.getScrollState();
+    },
+
+    _initTimeline: function(props) {
+        var initialEvent = props.eventId;
+        var pixelOffset = props.eventPixelOffset;
+        return this._loadTimeline(initialEvent, pixelOffset);
+    },
+
+    /**
+     * (re)-load the event timeline, and initialise the scroll state, centered
+     * around the given event.
+     *
+     * @param {string?}  eventId the event to focus on. If undefined, will
+     *    scroll to the bottom of the room.
+     *
+     * @param {number?} pixelOffset   offset to position the given event at
+     *    (pixels from the bottom of the view). If undefined, will put the
+     *    event in the middle of the view.
+     *
+     * returns a promise which will resolve when the load completes.
+     */
+    _loadTimeline: function(eventId, pixelOffset) {
+        // TODO: we could optimise this, by not resetting the window if the
+        // event is in the current window (though it's not obvious how we can
+        // tell if the current window is on the live event stream)
+
+        this.setState({
+            events: [],
+            timelineLoading: true,
+        });
+
+        this._timelineWindow = new Matrix.TimelineWindow(
+            MatrixClientPeg.get(), this.props.room,
+            {windowLimit: TIMELINE_CAP});
+
+        return this._timelineWindow.load(eventId, INITIAL_SIZE).then(() => {
+            debuglog("TimelinePanel: timeline loaded");
+            this._onTimelineUpdated(true);
+        }).finally(() => {
+            this.setState({
+                timelineLoading: false,
+            }, () => {
+                // initialise the scroll state of the message panel
+                if (!this.refs.messagePanel) {
+                    // this shouldn't happen.
+                    console.log("can't initialise scroll state because " +
+                                "messagePanel didn't load");
+                    return;
+                }
+                if (eventId) {
+                    this.refs.messagePanel.scrollToEvent(eventId, pixelOffset);
+                } else {
+                    this.refs.messagePanel.scrollToBottom();
+                }
+
+                this.sendReadReceipt();
+            });
+        });
+    },
+
+    _onTimelineUpdated: function(gotResults) {
+        // we might have switched rooms since the load started - just bin
+        // the results if so.
+        if (this.unmounted) return;
+
+        if (gotResults) {
+            this.setState({
+                events: this._timelineWindow.getEvents(),
+                canBackPaginate: this._timelineWindow.canPaginate(EventTimeline.BACKWARDS),
+            });
+        }
+    },
+
+    _indexForEventId: function(evId) {
+        for (var i = 0; i < this.state.events.length; ++i) {
+            if (evId == this.state.events[i].getId()) {
+                return i;
+            }
+        }
+        return null;
+    },
+
+    _getLastDisplayedEventIndexIgnoringOwn: function() {
+        var messagePanel = this.refs.messagePanel;
+        if (messagePanel === undefined) return null;
+
+        var wrapperRect = ReactDOM.findDOMNode(messagePanel).getBoundingClientRect();
+
+        for (var i = this.state.events.length-1; i >= 0; --i) {
+            var ev = this.state.events[i];
+
+            if (ev.sender && ev.sender.userId == MatrixClientPeg.get().credentials.userId) {
+                continue;
+            }
+
+            var node = messagePanel.getNodeForEventId(ev.getId());
+            if (!node) continue;
+
+            var boundingRect = node.getBoundingClientRect();
+
+            if (boundingRect.bottom < wrapperRect.bottom) {
+                return i;
+            }
+        }
+        return null;
+    },
+
+    /**
+     * get the id of the event corresponding to our user's latest read-receipt.
+     */
+    _getCurrentReadReceipt: function() {
+        var client = MatrixClientPeg.get();
+        // the client can be null on logout
+        if (client == null)
+            return null;
+
+        var myUserId = client.credentials.userId;
+        return this.props.room.getEventReadUpTo(myUserId);
+    },
+
+
+    render: function() {
+        var MessagePanel = sdk.getComponent("structures.MessagePanel");
+        var Loader = sdk.getComponent("elements.Spinner");
+
+        // just show a spinner while the timeline loads.
+        //
+        // put it in a div of the right class (mx_RoomView_messagePanel) so
+        // that the order in the roomview flexbox is correct, and
+        // mx_RoomView_messageListWrapper to position the inner div in the
+        // right place.
+        //
+        // Note that the click-on-search-result functionality relies on the
+        // fact that the messagePanel is hidden while the timeline reloads,
+        // but that the RoomHeader (complete with search term) continues to
+        // exist.
+        if (this.state.timelineLoading) {
+            return (
+                    <div className="mx_RoomView_messagePanel mx_RoomView_messageListWrapper">
+                        <Loader />
+                    </div>
+            );
+        }
+
+        // give the messagepanel a stickybottom if we're at the end of the
+        // live timeline, so that the arrival of new events triggers a
+        // scroll.
+        //
+        // Make sure that stickyBottom is *false* if we can paginate
+        // forwards, otherwise if somebody hits the bottom of the loaded
+        // events when viewing historical messages, we get stuck in a loop
+        // of paginating our way through the entire history of the room.
+        var stickyBottom = !this._timelineWindow.canPaginate(EventTimeline.FORWARDS);
+
+        return (
+            <MessagePanel ref="messagePanel"
+                    hidden={ this.props.hidden }
+                    events={ this.state.events }
+                    highlightedEventId={ this.props.highlightedEventId }
+                    readMarkerEventId={ this.state.readMarkerEventId }
+                    readMarkerGhostEventId={ this.state.readMarkerGhostEventId }
+                    suppressFirstDateSeparator={ this.state.canBackPaginate }
+                    ourUserId={ MatrixClientPeg.get().credentials.userId }
+                    stickyBottom={ stickyBottom }
+                    isConferenceUser={ this.props.isConferenceUser }
+                    onScroll={ this.props.onScroll }
+                    onFillRequest={ this.onMessageListFillRequest }
+            />
+        );
+    },
+});