fix(desktop): add idempotent binary setup to fix empty build output

`neu build` requires platform binaries in `bin/`, which are gitignored
and absent on fresh clones — producing an empty `dist/` folder.

Add [setup-binaries.js](cci:7://file:///c:/personal/personal/dev/forks/markdown-viewer-fork/desktop-app/setup-binaries.js:0:0-0:0) which downloads binaries via `neu update` only
when missing or when the pinned version in [neutralino.config.json](cci:7://file:///c:/personal/personal/dev/forks/markdown-viewer-fork/desktop-app/neutralino.config.json:0:0-0:0)
changes, tracked by a `bin/.version` marker file.

Wire it into the npm script chain via `setup` + `postsetup` hooks so
that `npm run dev`, `npm run build`, and `npm run build:all` all
ensure binaries exist before proceeding.

- Simplify Dockerfile from 3 stages to 2 (setup handled by npm hooks)
- Add explicit setup step in GitHub Actions workflow
- Update README with setup documentation

Author: ramezio

.github/workflows/desktop-build.yml

@@ -21,6 +21,10 @@ jobs:
         with:
           node-version: "lts/*"
 
+      - name: Setup Neutralinojs binaries
+        working-directory: desktop-app
+        run: npm run setup
+
       - name: Build all binaries (embedded + portable)
         working-directory: desktop-app
         run: npm run build:all

desktop-app/Dockerfile

@@ -1,27 +1,22 @@
-# Stage 1: Prepare resources by copying/transforming browser-version files
-FROM node:lts-alpine AS prepare
+# Build Neutralinojs desktop app binaries
+#
+# Context: repo root (see docker-compose.yml)
+# Output: /output/ contains dist/ artifacts
+
+FROM node:lts-alpine AS build
 
 WORKDIR /app
 
 # Copy the entire repo (context is the repo root)
 COPY . .
 
-# Run the prepare script to generate desktop-app resources
-RUN node desktop-app/prepare.js
-
-# Stage 2: Build Neutralinojs binaries
-FROM node:lts-alpine AS build
-
 WORKDIR /app/desktop-app
 
-# Copy only the desktop-app directory with prepared resources
-COPY --from=prepare /app/desktop-app .
-
-# Build both embedded + portable
+# Setup (download binaries + prepare resources) and build all variants
 RUN npm run build:all
 
 # Final stage: Export the dist artifacts
-FROM alpine:lts
+FROM alpine:latest
 
 WORKDIR /output
 

desktop-app/README.md

@@ -6,11 +6,14 @@ This is a desktop app port of [Markdown Viewer](https://github.com/ThisIs-Develo
 
 The desktop app **shares** its core files (`script.js`, `styles.css`, `assets/`) with the browser version in the repo root. A build script (`prepare.js`) copies these files into `resources/` and injects Neutralinojs-specific additions into `index.html` at build time.
 
+Neutralinojs platform binaries are managed by `setup-binaries.js`, which downloads them on first use and caches them in `bin/` (gitignored). The download is version-locked to `cli.binaryVersion` in `neutralino.config.json` and only re-triggered when that version changes.
+
 Desktop-only files (not generated):
 
 - `resources/js/main.js` — Neutralinojs lifecycle, tray menu, window events
 - `resources/js/neutralino.js` — Neutralinojs client library
 - `neutralino.config.json` — App configuration
+- `setup-binaries.js` — Idempotent binary setup (downloads on first use)
 
 ## Development
 
@@ -22,13 +25,21 @@ Desktop-only files (not generated):
 
 No installation is required. The app is built and run using `npx` (via npm scripts).
 
+Neutralinojs platform binaries are downloaded automatically on first build or dev run. To manually trigger the download:
+
+```bash
+npm run setup
+```
+
+Binaries are cached in `bin/` (gitignored) and only re-downloaded when `cli.binaryVersion` in `neutralino.config.json` changes.
+
 ### Running the app
 
 ```bash
 npm run dev
 ```
 
-This automatically runs `prepare.js` before starting the app. Hot-reload is enabled by default. Enable the browser inspector by setting `"enableInspector": true` in `neutralino.config.json`.
+This automatically runs `setup` (downloads binaries if needed and prepares resources) before starting the app. Hot-reload is enabled by default. Enable the browser inspector by setting `"enableInspector": true` in `neutralino.config.json`.
 
 For more information, see the [Neutralinojs documentation](https://neutralino.js.org/docs/cli/neu-cli#installation).
 

desktop-app/package.json

@@ -4,10 +4,11 @@
   "private": true,
   "description": "Neutralinojs desktop port of Markdown Viewer",
   "scripts": {
-    "prepare:resources": "node prepare.js",
-    "predev": "node prepare.js",
+    "setup": "node setup-binaries.js",
+    "postsetup": "node prepare.js",
+    "predev": "npm run setup",
     "dev": "npx -y @neutralinojs/neu@11.7.0 run",
-    "prebuild": "node prepare.js",
+    "prebuild": "npm run setup",
     "build": "npx -y @neutralinojs/neu@11.7.0 build --embed-resources",
     "build:portable": "npx -y @neutralinojs/neu@11.7.0 build --release",
     "build:all": "npm run build && npm run build:portable"

desktop-app/setup-binaries.js

@@ -0,0 +1,60 @@
+#!/usr/bin/env node
+
+/**
+ * setup-binaries.js — Idempotent Neutralinojs binary setup.
+ *
+ * Ensures the bin/ folder contains platform binaries matching the version
+ * pinned in neutralino.config.json (cli.binaryVersion). Downloads them
+ * via `neu update` only when missing or when the pinned version changes.
+ *
+ * A version marker (bin/.version) tracks the installed version so that
+ * repeated builds and dev runs skip the download entirely.
+ *
+ * Run from the desktop-app/ directory:
+ *   node setup-binaries.js
+ */
+
+const fs = require("fs");
+const path = require("path");
+const { execSync } = require("child_process");
+
+const CONFIG_FILE = path.resolve(__dirname, "neutralino.config.json");
+const BIN_DIR = path.resolve(__dirname, "bin");
+const VERSION_MARKER = path.join(BIN_DIR, ".version");
+
+/** Neu CLI package — same version used across all npm scripts */
+const NEU_CLI = "@neutralinojs/neu@11.7.0";
+
+const config = JSON.parse(fs.readFileSync(CONFIG_FILE, "utf-8"));
+const expectedVersion = config.cli.binaryVersion;
+
+if (!expectedVersion) {
+  console.error("✗ cli.binaryVersion not set in neutralino.config.json");
+  process.exit(1);
+}
+
+/** Check if binaries are already present and match the expected version */
+if (fs.existsSync(VERSION_MARKER)) {
+  const installed = fs.readFileSync(VERSION_MARKER, "utf-8").trim();
+  if (installed === expectedVersion) {
+    console.log(
+      `✓ Neutralinojs binaries v${expectedVersion} already present — skipping download`,
+    );
+    process.exit(0);
+  }
+  console.log(
+    `↻ Version changed (${installed} → ${expectedVersion}) — re-downloading`,
+  );
+}
+
+/** Download binaries + client library via neu update */
+console.log(`⬇ Downloading Neutralinojs v${expectedVersion} binaries...`);
+execSync(`npx -y ${NEU_CLI} update`, {
+  cwd: __dirname,
+  stdio: "inherit",
+});
+
+/** Write version marker so subsequent runs are no-ops */
+fs.mkdirSync(BIN_DIR, { recursive: true });
+fs.writeFileSync(VERSION_MARKER, expectedVersion, "utf-8");
+console.log(`✓ Neutralinojs binaries v${expectedVersion} ready`);