Move spec permalinks into their own class

This allows for Riot permalinks to be introduced without if-else ladders everywhere.

src/linkify-matrix.js

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import {baseUrl} from "./utils/permalinks/SpecPermalinks";
+import {baseUrl} from "./utils/permalinks/SpecPermalinkConstructor";
 
 function matrixLinkify(linkify) {
     // Text tokens

src/utils/permalinks/PermalinkConstructor.js

@@ -14,15 +14,24 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-export const host = "matrix.to";
-export const baseUrl = `https://${host}`;
-
 /**
- * Generates matrix.to permalinks
+ * Interface for classes that actually produce permalinks (strings).
+ * TODO: Convert this to a real TypeScript interface
  */
-export default class SpecPermalinks {
+export default class PermalinkConstructor {
-    constructor() {
+    forEvent(roomId: string, eventId: string, serverCandidates: string[]): string {
+        throw new Error("Not implemented");
     }
 
-    // TODO: The class
+    forRoom(roomIdOrAlias: string, serverCandidates: string[]): string {
+        throw new Error("Not implemented");
+    }
+
+    forGroup(groupId: string): string {
+        throw new Error("Not implemented");
+    }
+
+    forUser(userId: string): string {
+        throw new Error("Not implemented");
+    }
 }

src/utils/permalinks/RoomPermalinkCreator.js

@@ -17,7 +17,13 @@ limitations under the License.
 import MatrixClientPeg from "../../MatrixClientPeg";
 import isIp from "is-ip";
 import utils from 'matrix-js-sdk/lib/utils';
-import {host as matrixtoHost, baseUrl as matrixtoBaseUrl} from "SpecPermalinks";
+import SpecPermalinkConstructor, {
+    baseUrl as matrixtoBaseUrl,
+    host as matrixtoHost
+} from "./SpecPermalinkConstructor";
+import PermalinkConstructor from "./PermalinkConstructor";
+
+const SdkConfig = require("../../SdkConfig");
 
 // The maximum number of servers to pick when working out which servers
 // to add to permalinks. The servers are appended as ?via=example.org
@@ -126,15 +132,11 @@ export class RoomPermalinkCreator {
     }
 
     forEvent(eventId) {
-        const roomId = this._roomId;
+        return getPermalinkConstructor().forEvent(this._roomId, eventId, this._serverCandidates);
-        const permalinkBase = `${matrixtoBaseUrl}/#/${roomId}/${eventId}`;
-        return `${permalinkBase}${encodeServerCandidates(this._serverCandidates)}`;
     }
 
     forRoom() {
-        const roomId = this._roomId;
+        return getPermalinkConstructor().forRoom(this._roomId, this._serverCandidates);
-        const permalinkBase = `${matrixtoBaseUrl}/#/${roomId}`;
-        return `${permalinkBase}${encodeServerCandidates(this._serverCandidates)}`;
     }
 
     onRoomState(event) {
@@ -257,24 +259,22 @@ export class RoomPermalinkCreator {
 }
 
 export function makeUserPermalink(userId) {
-    return `${matrixtoBaseUrl}/#/${userId}`;
+    return getPermalinkConstructor().forUser(userId);
 }
 
 export function makeRoomPermalink(roomId) {
-    const permalinkBase = `${matrixtoBaseUrl}/#/${roomId}`;
-
     if (!roomId) {
         throw new Error("can't permalink a falsey roomId");
     }
 
     // If the roomId isn't actually a room ID, don't try to list the servers.
     // Aliases are already routable, and don't need extra information.
-    if (roomId[0] !== '!') return permalinkBase;
+    if (roomId[0] !== '!') return getPermalinkConstructor().forRoom(roomId, []);
 
     const client = MatrixClientPeg.get();
     const room = client.getRoom(roomId);
     if (!room) {
-        return permalinkBase;
+        return getPermalinkConstructor().forRoom(roomId, []);
     }
     const permalinkCreator = new RoomPermalinkCreator(room);
     permalinkCreator.load();
@@ -282,12 +282,15 @@ export function makeRoomPermalink(roomId) {
 }
 
 export function makeGroupPermalink(groupId) {
-    return `${matrixtoBaseUrl}/#/${groupId}`;
+    return getPermalinkConstructor().forGroup(groupId);
 }
 
-export function encodeServerCandidates(candidates) {
+function getPermalinkConstructor(): PermalinkConstructor {
-    if (!candidates || candidates.length === 0) return '';
+    if (SdkConfig.get()['useRiotToCreatePermalinks']) {
-    return `?via=${candidates.map(c => encodeURIComponent(c)).join("&via=")}`;
+        // TODO: Return a RiotPermalinkConstructor
+    }
+
+    return new SpecPermalinkConstructor();
 }
 
 function getServerName(userId) {

src/utils/permalinks/SpecPermalinkConstructor.js

@@ -0,0 +1,50 @@
+/*
+Copyright 2019 The Matrix.org Foundation C.I.C.
+
+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 PermalinkConstructor from "./PermalinkConstructor";
+
+export const host = "matrix.to";
+export const baseUrl = `https://${host}`;
+
+/**
+ * Generates matrix.to permalinks
+ */
+export default class SpecPermalinkConstructor extends PermalinkConstructor {
+    constructor() {
+        super();
+    }
+
+    forEvent(roomId: string, eventId: string, serverCandidates: string[]): string {
+        return `${baseUrl}/#/${roomId}/${eventId}${this.encodeServerCandidates(serverCandidates)}`;
+    }
+
+    forRoom(roomIdOrAlias: string, serverCandidates: string[]): string {
+        return `${baseUrl}/#/${roomIdOrAlias}${this.encodeServerCandidates(serverCandidates)}`;
+    }
+
+    forUser(userId: string): string {
+        return `${baseUrl}/#/${userId}`;
+    }
+
+    forGroup(groupId: string): string {
+        return `${baseUrl}/#/${groupId}`;
+    }
+
+    encodeServerCandidates(candidates: string[]) {
+        if (!candidates || candidates.length === 0) return '';
+        return `?via=${candidates.map(c => encodeURIComponent(c)).join("&via=")}`;
+    }
+}