Refactor: split main.js into app/ modules

app/pathValidator.js

@@ -0,0 +1,32 @@
+const fs = require("fs");
+const path = require("path");
+const { logger } = require("../server/logger");
+
+let _defaultPath = null;
+
+function getDefaultDownloadPath() {
+  if (!_defaultPath) {
+    const { defaultDownloadFolder } = require("../server/helpers/path.helpers");
+    _defaultPath = defaultDownloadFolder;
+  }
+  return _defaultPath;
+}
+
+function validateDownloadPath(userPath) {
+  const { isSafePath } = require("../server/helpers/validation.helpers");
+
+  if (!userPath) return getDefaultDownloadPath();
+
+  try {
+    const resolved = fs.realpathSync(path.resolve(userPath));
+    if (!isSafePath(resolved)) {
+      throw new Error("Path not allowed: system folders are blocked!");
+    }
+    return resolved;
+  } catch (err) {
+    logger.error(`Invalid download path: ${userPath} — ${err.message}`);
+    throw new Error(`Invalid or inaccessible path: ${err.message}`);
+  }
+}
+
+module.exports = { validateDownloadPath, getDefaultDownloadPath };