cram OpenRoomsStore between RoomViewStore and dispatcher

the idea is that it will keep a RoomViewStore for every
room on the screen, and also keep track of which one is
the current one.

For now, it just replicates the existing functionality of
having just 1 room on the screen.

Since the RoomViewStore just has access to a local dispatcher
and not the global anymore, all dispatching of actions
needs to be moved to the OpenRoomsStore, so room alias resolving,
event forwarding, ... is moved there.

src/stores/OpenRoomsStore.js

@@ -0,0 +1,166 @@
+/*
+Copyright 2018 New Vector 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.
+*/
+import MatrixDispatcher from '../matrix-dispatcher';
+import dis from '../dispatcher';
+import {RoomViewStore} from './RoomViewStore';
+import {Store} from 'flux/utils';
+import MatrixClientPeg from '../MatrixClientPeg';
+
+/**
+ * A class for keeping track of the RoomViewStores of the rooms shown on the screen.
+ * Routes the dispatcher actions to the store of currently active room.
+ */
+class OpenRoomsStore extends Store {
+    constructor() {
+        super(dis);
+
+        // Initialise state
+        this._state = {
+            room: {
+                store: null,
+                dispatcher: null
+            },
+        };
+
+        this._forwardingEvent = null;
+    }
+
+    getRoomStore() {
+        return this._state.room.store;
+    }
+
+    getCurrentRoomStore() {
+        return this.getRoomStore(); // just one room for now
+    }
+
+    _setState(newState) {
+        this._state = Object.assign(this._state, newState);
+        this.__emitChange();
+    }
+
+    _cleanupRoom() {
+        const room = this._state.room;
+        room.dispatcher.unregister(room.store.getDispatchToken());
+        this._setState({
+            room: {
+                store: null,
+                dispatcher: null
+            },
+        });
+    }
+
+    _createRoom() {
+        const dispatcher = new MatrixDispatcher();
+        this._setState({
+            room: {
+                store: new RoomViewStore(dispatcher),
+                dispatcher,
+            },
+        });
+    }
+
+    _forwardAction(payload) {
+        if (this._state.room.dispatcher) {
+            this._state.room.dispatcher.dispatch(payload, true);
+        }
+    }
+
+    async _resolveRoomAlias(payload) {
+        try {
+            const result = await MatrixClientPeg.get()
+                .getRoomIdForAlias(payload.room_alias);
+            dis.dispatch({
+                action: 'view_room',
+                room_id: result.room_id,
+                event_id: payload.event_id,
+                highlighted: payload.highlighted,
+                room_alias: payload.room_alias,
+                auto_join: payload.auto_join,
+                oob_data: payload.oob_data,
+            });
+        } catch(err) {
+            this._forwardAction({
+                action: 'view_room_error',
+                room_id: null,
+                room_alias: payload.room_alias,
+                err: err,
+            });
+        }
+    }
+
+    __onDispatch(payload) {
+        switch (payload.action) {
+            // view_room:
+            //      - room_alias:   '#somealias:matrix.org'
+            //      - room_id:      '!roomid123:matrix.org'
+            //      - event_id:     '$213456782:matrix.org'
+            //      - event_offset: 100
+            //      - highlighted:  true
+            case 'view_room':
+                console.log("!!! OpenRoomsStore: view_room", payload);
+                if (!payload.room_id && payload.room_alias) {
+                    this._resolveRoomAlias(payload);
+                }
+                const currentStore = this.getCurrentRoomStore();
+                if (currentStore &&
+                    (!payload.room_alias || payload.room_alias !== currentStore.getRoomAlias()) &&
+                    (!currentStore.getRoomId() || payload.room_id !== currentStore.getRoomId())
+                ) {
+                    console.log("OpenRoomsStore: _cleanupRoom");
+                    this._cleanupRoom();
+                }
+                if (!this._state.room.store) {
+                    console.log("OpenRoomsStore: _createRoom");
+                    this._createRoom();
+                }
+                console.log("OpenRoomsStore: _forwardAction");
+                this._forwardAction(payload);
+                if (this._forwardingEvent) {
+                    dis.dispatch({
+                        action: 'send_event',
+                        room_id: payload.room_id,
+                        event: this._forwardingEvent,
+                    });
+                    this._forwardingEvent = null;
+                }
+                break;
+            case 'view_my_groups':
+            case 'view_group':
+                this._forwardAction(payload);
+                this._cleanupRoom();
+                break;
+            case 'will_join':
+            case 'cancel_join':
+            case 'join_room':
+            case 'join_room_error':
+            case 'on_logged_out':
+            case 'reply_to_event':
+            case 'open_room_settings':
+            case 'close_settings':
+                this._forwardAction(payload);
+                break;
+            case 'forward_event':
+                this._forwardingEvent = payload.event;
+                break;
+        }
+    }
+}
+
+let singletonOpenRoomsStore = null;
+if (!singletonOpenRoomsStore) {
+    singletonOpenRoomsStore = new OpenRoomsStore();
+}
+module.exports = singletonOpenRoomsStore;

src/stores/RoomViewStore.js

@@ -53,8 +53,8 @@ const INITIAL_STATE = {
 *  with a subset of the js-sdk.
  *  ```
  */
-class RoomViewStore extends Store {
-    constructor() {
+export class RoomViewStore extends Store {
+    constructor(dis) {
         super(dis);
 
         // Initialise state
@@ -85,6 +85,8 @@ class RoomViewStore extends Store {
                 });
                 break;
             case 'view_room_error':
+                // should not go over dispatcher anymore
+                // but be internal to RoomViewStore
                 this._viewRoomError(payload);
                 break;
             case 'will_join':
@@ -150,22 +152,11 @@ class RoomViewStore extends Store {
                 // pull the user out of Room Settings
                 isEditingSettings: false,
             };
-
-            if (this._state.forwardingEvent) {
-                dis.dispatch({
-                    action: 'send_event',
-                    room_id: newState.roomId,
-                    event: this._state.forwardingEvent,
-                });
-            }
-
             this._setState(newState);
-
             if (payload.auto_join) {
                 this._joinRoom(payload);
             }
         } else if (payload.room_alias) {
-            // Resolve the alias and then do a second dispatch with the room ID acquired
             this._setState({
                 roomId: null,
                 initialEventId: null,
@@ -175,25 +166,6 @@ class RoomViewStore extends Store {
                 roomLoading: true,
                 roomLoadError: null,
             });
-            MatrixClientPeg.get().getRoomIdForAlias(payload.room_alias).done(
-            (result) => {
-                dis.dispatch({
-                    action: 'view_room',
-                    room_id: result.room_id,
-                    event_id: payload.event_id,
-                    highlighted: payload.highlighted,
-                    room_alias: payload.room_alias,
-                    auto_join: payload.auto_join,
-                    oob_data: payload.oob_data,
-                });
-            }, (err) => {
-                dis.dispatch({
-                    action: 'view_room_error',
-                    room_id: null,
-                    room_alias: payload.room_alias,
-                    err: err,
-                });
-            });
         }
     }
 
@@ -330,8 +302,7 @@ class RoomViewStore extends Store {
     }
 }
 
-let singletonRoomViewStore = null;
-if (!singletonRoomViewStore) {
-    singletonRoomViewStore = new RoomViewStore();
-}
-module.exports = singletonRoomViewStore;
+const MatrixDispatcher = require("../matrix-dispatcher");
+const blubber = new RoomViewStore(new MatrixDispatcher());
+
+export default blubber;