Windows: Patch host updater to reinject (#138)

4 files changed, 144 insertions, 20 deletions

diff --git a/scripts/patcher/install.js b/scripts/patcher/install.js
index 7fd3a8c..036b0fa 100755
--- a/scripts/patcher/install.js
+++ b/scripts/patcher/install.js
@@ -103,7 +103,7 @@ async function install(installations) {
 
         fs.writeFileSync(
             path.join(dir, "index.js"),
-            `require("${ENTRYPOINT}"); require("../app.asar");`
+            `require("${ENTRYPOINT}");`
         );
         fs.writeFileSync(
             path.join(dir, "package.json"),
diff --git a/src/api/DataStore/index.ts b/src/api/DataStore/index.ts
index f2b1df6..49c8595 100644
--- a/src/api/DataStore/index.ts
+++ b/src/api/DataStore/index.ts
@@ -1,21 +1,4 @@
-/*
- * Vencord, a modification for Discord's desktop app
- * Copyright (c) 2022 Vendicated and contributors
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
-*/
-
+/* eslint-disable header/header */
 
 /*!
  * idb-keyval v6.2.0
diff --git a/src/patchWin32Updater.ts b/src/patchWin32Updater.ts
new file mode 100644
index 0000000..2044615
--- /dev/null
+++ b/src/patchWin32Updater.ts
@@ -0,0 +1,107 @@
+/*
+ * Vencord, a modification for Discord's desktop app
+ * Copyright (c) 2022 Vendicated and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+import { app, autoUpdater } from "electron";
+import { dirname, basename, join } from "path";
+import { readdirSync, existsSync, mkdirSync, writeFileSync } from "fs";
+
+const { setAppUserModelId } = app;
+
+// Apparently requiring Discords updater too early leads into issues,
+// copied this workaround from powerCord
+app.setAppUserModelId = function (id: string) {
+    app.setAppUserModelId = setAppUserModelId;
+
+    setAppUserModelId.call(this, id);
+
+    patchUpdater();
+};
+
+function isNewer($new: string, old: string) {
+    const newParts = $new.slice(4).split(".").map(Number);
+    const oldParts = old.slice(4).split(".").map(Number);
+
+    for (let i = 0; i < oldParts.length; i++) {
+        if (newParts[i] > oldParts[i]) return true;
+        if (newParts[i] < oldParts[i]) return false;
+    }
+    return false;
+}
+
+function patchLatest() {
+    const currentAppPath = dirname(process.execPath);
+    const currentVersion = basename(currentAppPath);
+    const discordPath = join(currentAppPath, "..");
+
+    const latestVersion = readdirSync(discordPath).reduce((prev, curr) => {
+        return (curr.startsWith("app-") && isNewer(curr, prev))
+            ? curr
+            : prev;
+    }, currentVersion as string);
+
+    if (latestVersion === currentVersion) return;
+
+    const app = join(discordPath, latestVersion, "resources", "app");
+    if (existsSync(app)) return;
+
+    console.info("[Vencord] Detected Host Update. Repatching...");
+
+    const patcherPath = join(__dirname, "patcher.js");
+    mkdirSync(app);
+    writeFileSync(join(app, "package.json"), JSON.stringify({
+        name: "discord",
+        main: "index.js"
+    }));
+    writeFileSync(join(app, "index.js"), `require(${JSON.stringify(patcherPath)});`);
+}
+
+// Windows Host Updates install to a new folder app-{HOST_VERSION}, so we
+// need to reinject
+function patchUpdater() {
+    const main = require.main!;
+    const buildInfo = require(join(process.resourcesPath, "build_info.json"));
+
+    try {
+        if (buildInfo?.newUpdater) {
+            const autoStartScript = join(main.filename, "..", "autoStart", "win32.js");
+            const { update } = require(autoStartScript);
+
+            // New Updater Injection
+            require.cache[autoStartScript]!.exports.update = function () {
+                patchLatest();
+                update.apply(this, arguments);
+            };
+        } else {
+            const hostUpdaterScript = join(main.filename, "..", "hostUpdater.js");
+            const { quitAndInstall } = require(hostUpdaterScript);
+
+            // Old Updater Injection
+            require.cache[hostUpdaterScript]!.exports.quitAndInstall = function () {
+                patchLatest();
+                quitAndInstall.apply(this, arguments);
+            };
+        }
+    } catch {
+        // OpenAsar uses electrons autoUpdater on Windows
+        const { quitAndInstall } = autoUpdater;
+        autoUpdater.quitAndInstall = function () {
+            patchLatest();
+            quitAndInstall.call(this);
+        };
+    }
+}
diff --git a/src/patcher.ts b/src/patcher.ts
index eca35f0..14f0812 100644
--- a/src/patcher.ts
+++ b/src/patcher.ts
@@ -17,13 +17,27 @@
 */
 
 import electron, { app, BrowserWindowConstructorOptions } from "electron";
-import { join } from "path";
+import { dirname, join } from "path";
 import { initIpc } from "./ipcMain";
 import { installExt } from "./ipcMain/extensions";
 import { readSettings } from "./ipcMain/index";
+import { readFileSync } from "fs";
 
 console.log("[Vencord] Starting up...");
 
+// Our injector file at app/index.js
+const injectorPath = require.main!.filename;
+// The original app.asar
+const discordPath = join(dirname(injectorPath), "..", "app.asar");
+// Full main path Discord uses
+require.main!.filename = join(discordPath, "app_bootstrap/index.js");
+// @ts-ignore Untyped method? Dies from cringe
+app.setAppPath(discordPath);
+
+// Repatch after host updates on Windows
+if (process.platform === "win32")
+    require("./patchWin32Updater");
+
 class BrowserWindow extends electron.BrowserWindow {
     constructor(options: BrowserWindowConstructorOptions) {
         if (options?.webPreferences?.preload && options.title) {
@@ -88,3 +102,23 @@ electron.app.whenReady().then(() => {
         cb({ cancel: false, responseHeaders });
     });
 });
+
+console.log("[Vencord] Loading original Discord app.asar");
+// Legacy Vencord Injector requires "../app.asar". However, because we
+// restore the require.main above this is messed up, so monkey patch Module._load to
+// redirect such requires
+// FIXME: remove this eventually
+if (readFileSync(injectorPath, "utf-8").includes('require("../app.asar")')) {
+    console.warn("[Vencord] [--> WARNING <--] You have a legacy Vencord install. Please reinject");
+    const Module = require("module");
+    const loadModule = Module._load;
+    Module._load = function (path: string) {
+        if (path === "../app.asar") {
+            Module._load = loadModule;
+            arguments[0] = require.main!.filename;
+        }
+        return loadModule.apply(this, arguments);
+    };
+} else {
+    require(discordPath);
+}