1 files changed, 96 insertions, 0 deletions

diff --git a/packages/preload/src/contextBridge/createSophieRenderer.ts b/packages/preload/src/contextBridge/createSophieRenderer.ts
new file mode 100644
index 0000000..2055080
--- /dev/null
+++ b/packages/preload/src/contextBridge/createSophieRenderer.ts
@@ -0,0 +1,96 @@
+/*
+ * Copyright (C)  2021-2022 Kristóf Marussy <kristof@marussy.com>
+ *
+ * This file is part of Sophie.
+ *
+ * Sophie is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, version 3.
+ *
+ * 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import {
+  Action,
+  action,
+  MainToRendererIpcMessage,
+  RendererToMainIpcMessage,
+  sharedStore,
+  SharedStoreListener,
+  SophieRenderer,
+} from '@sophie/shared';
+import { ipcRenderer } from 'electron';
+import log from 'loglevel';
+import type { IJsonPatch } from 'mobx-state-tree';
+
+class SharedStoreConnector {
+  private onSharedStoreChangeCalled = false;
+
+  private listener: SharedStoreListener | null = null;
+
+  constructor(private readonly allowReplaceListener: boolean) {
+    ipcRenderer.on(MainToRendererIpcMessage.SharedStorePatch, (_event, patch) => {
+      try {
+        // `mobx-state-tree` will validate the patch, so we can safely cast here.
+        this.listener?.onPatch(patch as IJsonPatch);
+      } catch (err) {
+        log.error('Shared store listener onPatch failed', err);
+        this.listener = null;
+      }
+    });
+  }
+
+  async onSharedStoreChange(listener: SharedStoreListener): Promise<void> {
+    if (this.onSharedStoreChangeCalled && !this.allowReplaceListener) {
+      throw new Error('Shared store change listener was already set');
+    }
+    this.onSharedStoreChangeCalled = true;
+    let success = false;
+    let snapshot: unknown | null = null;
+    try {
+      snapshot = await ipcRenderer.invoke(RendererToMainIpcMessage.GetSharedStoreSnapshot);
+      success = true;
+    } catch (err) {
+      log.error('Failed to get initial shared store snapshot', err);
+    }
+    if (success) {
+      if (sharedStore.is(snapshot)) {
+        listener.onSnapshot(snapshot);
+        this.listener = listener;
+        return;
+      }
+      log.error('Got invalid initial shared store snapshot', snapshot);
+    }
+    throw new Error('Failed to connect to shared store');
+  }
+}
+
+function dispatchAction(actionToDispatch: Action): void {
+  // Let the full zod parse error bubble up to the main world,
+  // since all data it may contain was provided from the main world.
+  const parsedAction = action.parse(actionToDispatch);
+  try {
+    ipcRenderer.send(RendererToMainIpcMessage.DispatchAction, parsedAction);
+  } catch (err) {
+    // Do not leak IPC failure details into the main world.
+    const message = 'Failed to dispatch action';
+    log.error(message, actionToDispatch, err);
+    throw new Error(message);
+  }
+}
+
+export default function createSophieRenderer(allowReplaceListener: boolean): SophieRenderer {
+  const connector = new SharedStoreConnector(allowReplaceListener);
+  return {
+    onSharedStoreChange: connector.onSharedStoreChange.bind(connector),
+    dispatchAction,
+  };
+}