Add cross-platform yt-dlp resolution without breaking Windows builds

README.md

@@ -67,6 +67,31 @@ npm run build:renderer
 npm start
 ```
 
+## Build Prerequisites (Linux / macOS)
+
+On Linux or macOS, make sure `yt-dlp` is already installed and available in your `$PATH`.
+
+**Linux:**
+
+Download the binary from [yt-dlp releases](https://github.com/yt-dlp/yt-dlp/releases), make it executable, and place it in your `PATH`:
+
+```bash
+chmod +x yt-dlp
+sudo mv yt-dlp /usr/local/bin/
+```
+
+**macOS:**
+
+```bash
+brew install yt-dlp
+```
+
+## Build (Linux / macOS)
+
+```bash
+npm run build
+```
+
 ## Build Windows Installer + Portable
 
 ```bash

electron/main.js

@@ -111,7 +111,15 @@ function isUsableFfmpegBinary(candidatePath) {
   }
 }
 
-function ensureManagedYtDlpPath() {
+function unixManagedYtDlpPath() {
+  const result = spawnSync("which", ["yt-dlp"]);
+  if (result.status === 0 && result.stdout) {
+    return result.stdout.toString().trim();
+  }
+  throw new Error("yt-dlp not found in PATH. Please install yt-dlp and ensure it is accessible in your system PATH. See README for installation instructions.");
+}
+
+function winManagedYtDlpPath() {
   const managedDir = path.join(app.getPath("userData"), "bin");
   const managedPath = path.join(managedDir, "yt-dlp.exe");
   if (fs.existsSync(managedPath)) {
@@ -128,6 +136,16 @@ function ensureManagedYtDlpPath() {
   return managedPath;
 }
 
+function ensureManagedYtDlpPath() {
+  if (process.platform === "win32") {
+    return winManagedYtDlpPath();
+  }
+  if (process.platform === "linux" || process.platform === "darwin") {
+    return unixManagedYtDlpPath();
+  }
+  throw new Error(`Unsupported platform: ${process.platform}`);
+}
+
 function getFfmpegPath() {
   const managed = path.join(app.getPath("userData"), "bin", "ffmpeg.exe");
   if (isUsableFfmpegBinary(managed)) {