♻️ refactor: extract jsonFile helper for file-backed JSON stores

src/main/accounts/store.ts

@@ -1,7 +1,7 @@
 import { app } from "electron";
 import { join } from "node:path";
-import { copyFileSync, existsSync, readFileSync, rmSync } from "node:fs";
-import { writeFileAtomicSync } from "../lib/atomicFile";
+import { copyFileSync, existsSync, rmSync } from "node:fs";
+import { jsonFile } from "../lib/jsonFile";
 import type { Account, AccountsState } from "../../shared/types/auth";
 
 const dir = () => join(app.getPath("userData"), "sessions");
@@ -15,17 +15,9 @@ interface Registry {
   accounts: Account[];
 }
 
-function read(): Registry {
-  try {
-    return JSON.parse(readFileSync(registryPath(), "utf8")) as Registry;
-  } catch {
-    return { active: null, accounts: [] };
-  }
-}
-
-function write(reg: Registry): void {
-  writeFileAtomicSync(registryPath(), JSON.stringify(reg, null, 2));
-}
+const registry = jsonFile<Registry>(registryPath, () => ({ active: null, accounts: [] }));
+const read = registry.read;
+const write = registry.write;
 
 export function listAccounts(): AccountsState {
   const reg = read();

src/main/config/appConfig.ts

@@ -1,7 +1,7 @@
 import { app } from "electron";
 import { join } from "node:path";
-import { existsSync, readFileSync } from "node:fs";
-import { writeFileAtomicSync } from "../lib/atomicFile";
+import { existsSync } from "node:fs";
+import { jsonFile } from "../lib/jsonFile";
 import type { AppConfig, PreferredRegion } from "../../shared/types/appConfig";
 import { detectedGamePath } from "../game/steam";
 
@@ -10,12 +10,15 @@ const path = () => join(app.getPath("userData"), "app-config.json");
 type StoredConfig = Omit<AppConfig, "version" | "detectedGamePath">;
 const DEFAULTS: StoredConfig = { gamePath: null, preferredRegion: "auto" };
 
-function readStored(): StoredConfig {
-  try {
-    return { ...DEFAULTS, ...(JSON.parse(readFileSync(path(), "utf8")) as Partial<StoredConfig>) };
-  } catch {
-    return { ...DEFAULTS };
-  }
+const configFile = jsonFile<StoredConfig>(
+  path,
+  () => ({ ...DEFAULTS }),
+  (raw) => ({ ...DEFAULTS, ...(raw as Partial<StoredConfig>) }),
+);
+const readStored = configFile.read;
+
+function writeStored(next: StoredConfig): void {
+  configFile.write(next);
 }
 
 function withDerived(stored: StoredConfig): AppConfig {
@@ -32,7 +35,7 @@ export function preferredRegion(): PreferredRegion {
 
 export function setPreferredRegion(region: PreferredRegion): AppConfig {
   const next: StoredConfig = { ...readStored(), preferredRegion: region };
-  writeFileAtomicSync(path(), JSON.stringify(next, null, 2));
+  writeStored(next);
   return withDerived(next);
 }
 
@@ -46,6 +49,6 @@ export function setGamePath(gamePath: string | null): AppConfig {
     throw new Error("That path doesn't exist on disk.");
   }
   const next: StoredConfig = { ...readStored(), gamePath: trimmed };
-  writeFileAtomicSync(path(), JSON.stringify(next, null, 2));
+  writeStored(next);
   return withDerived(next);
 }

src/main/enhancements/service.ts

@@ -1,7 +1,6 @@
 import { app } from "electron";
 import { join } from "node:path";
-import { readFileSync } from "node:fs";
-import { writeFileAtomicSync } from "../lib/atomicFile";
+import { jsonFile } from "../lib/jsonFile";
 import { logger } from "../debug/logger";
 import type {
   EnhancementId,
@@ -17,17 +16,9 @@ const storePath = () => join(app.getPath("userData"), "enhancements.json");
 
 type Prefs = Partial<Record<EnhancementId, boolean>>;
 
-function readPrefs(): Prefs {
-  try {
-    return JSON.parse(readFileSync(storePath(), "utf8")) as Prefs;
-  } catch {
-    return {};
-  }
-}
-
-function writePrefs(prefs: Prefs): void {
-  writeFileAtomicSync(storePath(), JSON.stringify(prefs, null, 2));
-}
+const prefsFile = jsonFile<Prefs>(storePath, () => ({}));
+const readPrefs = prefsFile.read;
+const writePrefs = prefsFile.write;
 
 function screenshotState(): EnhancementState {
   const s = screenshot.status();

src/main/lib/jsonFile.ts

@@ -0,0 +1,21 @@
+import { readFileSync } from "node:fs";
+import { writeFileAtomicSync } from "./atomicFile";
+
+export function jsonFile<T>(
+  path: () => string,
+  fallback: () => T,
+  parse: (raw: unknown) => T = (raw) => raw as T,
+) {
+  return {
+    read(): T {
+      try {
+        return parse(JSON.parse(readFileSync(path(), "utf8")));
+      } catch {
+        return fallback();
+      }
+    },
+    write(value: T): void {
+      writeFileAtomicSync(path(), JSON.stringify(value, null, 2));
+    },
+  };
+}

src/main/windowState.ts

@@ -1,19 +1,13 @@
 import { app, screen, type BrowserWindow, type Rectangle } from "electron";
 import { join } from "node:path";
-import { readFileSync } from "node:fs";
-import { writeFileAtomicSync } from "./lib/atomicFile";
+import { jsonFile } from "./lib/jsonFile";
 
 type Bounds = Rectangle & { maximized: boolean };
 
 const path = () => join(app.getPath("userData"), "window-state.json");
 
-function read(): Partial<Bounds> | null {
-  try {
-    return JSON.parse(readFileSync(path(), "utf8")) as Partial<Bounds>;
-  } catch {
-    return null;
-  }
-}
+const stateFile = jsonFile<Partial<Bounds> | null>(path, () => null);
+const read = stateFile.read;
 
 function onScreen(b: Rectangle): boolean {
   return screen.getAllDisplays().some((d) => {
@@ -47,10 +41,7 @@ export function trackBounds(win: BrowserWindow): void {
 
   const save = (): void => {
     if (win.isDestroyed()) return;
-    writeFileAtomicSync(
-      path(),
-      JSON.stringify({ ...normalBounds, maximized: win.isMaximized() }, null, 2),
-    );
+    stateFile.write({ ...normalBounds, maximized: win.isMaximized() });
   };
 
   const remember = (): void => {