From 5a5588f1e3f0c12f61b7f856e3aedfec3d87a41c Mon Sep 17 00:00:00 2001
From: hippoz <10706925-hippoz@users.noreply.gitlab.com>
Date: Fri, 17 Mar 2023 22:46:49 +0200
Subject: [PATCH] fix and improve matrix layer

---
 src/routes/matrix/index.ts | 109 ++++++++++++++++++++-----------------
 1 file changed, 60 insertions(+), 49 deletions(-)

diff --git a/src/routes/matrix/index.ts b/src/routes/matrix/index.ts
index d932c1e..9e5ff07 100644
--- a/src/routes/matrix/index.ts
+++ b/src/routes/matrix/index.ts
@@ -12,6 +12,9 @@ const router = express.Router();
 
 router.use(cors());
 
+const isInt = (val: any) => typeof val === "number" && Number.isSafeInteger(val);
+const isUint = (val: any) => (isInt(val) && val >= 0);
+
 const matrixProtocol = process.env.MATRIX_PROTOCOL ? process.env.MATRIX_PROTOCOL : "http";
 const matrixHomeserverBaseUrl = process.env.MATRIX_HOMESERVER_BASE_URL ? process.env.MATRIX_HOMESERVER_BASE_URL : "localhost:3000";
 const matrixWaffleAppUrl = process.env.MATRIX_WAFFLE_APP_URL ? process.env.MATRIX_WAFFLE_APP_URL : "localhost:3000";
@@ -47,22 +50,60 @@ const matrixUserProfile = (matrixUserId: string) => {
     };
 };
 
+const cursorType = "waffletrackv1";
+
 interface MatrixSyncCursors {
-    [channel_id: number]: number;
+    type: string,
+    chan: {[channel_id: number]: number};
 };
 
-async function buildSyncPayload(user: User, cursors: MatrixSyncCursors, onlyOutstandingEvents: boolean, client: PoolClient, channels: Channel[]) {
+function parseCursor(cursor: string | null): MatrixSyncCursors | null {
+    if (!cursor) {
+        return null;
+    }
+    let json;
+    try {
+        json = JSON.parse(cursor);
+    } catch(O_o) {
+        return null;
+    }
+
+    if (json.type !== "waffletrackv1") {
+        return null;
+    }
+
+    if (typeof json.chan !== "object") {
+        return null;
+    }
+
+    for (const [key, value] of Object.entries(json.chan)) {
+        if (!isUint(parseInt(key)) || !isUint(value)) {
+            return null;
+        }
+    }
+
+    return json;
+}
+
+function cursorNew(): MatrixSyncCursors {
+    return {
+        type: cursorType,
+        chan: {}
+    }
+}
+
+async function buildSyncPayload(user: User, cursors: MatrixSyncCursors, onlyOutstandingEvents: boolean, channels: Channel[]) {
     const joinedChannels: any[any] = {};
-    let nextBatchCursors = "";
+    const nextBatchCursors = cursorNew();
     for (let i = 0; i < channels.length; i++) {
         const channel = channels[i];
         const roomId = `!${channel.id}:${matrixHomeserverBaseUrl}`;
 
         let channelMessagesResult;
-        if (cursors[channel.id]) {
-            channelMessagesResult = await client.query(getMessagesByChannelAfterPage(50), [cursors[channel.id], channel.id]);
+        if (cursors.chan[channel.id]) {
+            channelMessagesResult = await query(getMessagesByChannelAfterPage(50), [cursors.chan[channel.id], channel.id]);
         } else {
-            channelMessagesResult = await client.query(getMessagesByChannelFirstPage(50), [channel.id]);
+            channelMessagesResult = await query(getMessagesByChannelFirstPage(50), [channel.id]);
         }
         const messages = channelMessagesResult && channelMessagesResult.rows ? channelMessagesResult.rows.reverse() : [];
         const messagesTimeline = messages.map(e => ({
@@ -78,9 +119,9 @@ async function buildSyncPayload(user: User, cursors: MatrixSyncCursors, onlyOuts
         }));
 
         if (messages.length > 0) {
-            nextBatchCursors += `${channel.id}:${messages[messages.length - 1].id};`;
-        } else if (cursors[channel.id]) {
-            nextBatchCursors += `${channel.id}:${cursors[channel.id]};`;
+            nextBatchCursors.chan[channel.id] = messages[messages.length - 1].id;
+        } else if (cursors.chan[channel.id]) {
+            nextBatchCursors.chan[channel.id] = cursors.chan[channel.id];
         }
 
         if (messages.length < 1 && onlyOutstandingEvents) {
@@ -139,7 +180,7 @@ async function buildSyncPayload(user: User, cursors: MatrixSyncCursors, onlyOuts
     }
 
     return {
-        next_batch: nextBatchCursors,
+        next_batch: JSON.stringify(nextBatchCursors),
         rooms: {
             invite: {},
             join: joinedChannels,
@@ -335,46 +376,16 @@ router.get(
             isInitial = false;
         }
 
-        await withClient((client: PoolClient) => {
-            return new Promise(async (resolve, reject) => {
-                const channelsResult = await client.query("SELECT id, name, owner_id FROM channels");
-                if (!channelsResult) return;
-                const channels = channelsResult.rows || [];    
+        const channelsResult = await query("SELECT id, name, owner_id FROM channels");
+        if (!channelsResult) return;
+        const channels = channelsResult.rows;
 
-                const sendPayload = async () => {
-                    const cursors: MatrixSyncCursors = {};
-                    if (since) {
-                        const sinceParts = since.split(";");
-                        if (sinceParts.length < 100) {
-                            sinceParts.forEach((part) => {
-                                const def = part.split(":");
-                                if (def.length !== 2) return;
-                                const channelId = parseInt(def[0]);
-                                const page = parseInt(def[1]);
-                                if (!isNaN(channelId) && isFinite(channelId) && !isNaN(page) && isFinite(page)) {
-                                    cursors[channelId] = page;
-                                }
-                            });
-                        }
-                    }
-            
-                    res.json(await buildSyncPayload({
-                        id: 3,
-                        username: "test",
-                        is_superuser: true,
-                        avatar: null
-                    }, cursors, !isInitial, client, channels));
-                };
-        
-                if (timeout) {
-                    let dispatchChannels = ["*"];
-                    channels.forEach(channel => dispatchChannels.push(`channel:${channel.id}`));
-                    await waitForEvent(dispatchChannels, timeout);
-                }
-                await sendPayload();
-                resolve(true);
-            });
-        });
+        if (timeout) {
+            const dispatchChannels = channels.map(channel => `channel:${channel.id}`);
+            dispatchChannels.push("*");
+            await waitForEvent(dispatchChannels, timeout);
+        }
+        res.json(await buildSyncPayload(req.publicUser, parseCursor(since) ?? cursorNew(), !isInitial, channels));
     }
 );