Solution

src/app.js

@@ -1 +1,51 @@
-// write code here
+const fs = require('fs');
+const path = require('path');
+
+function moveFile(src, dest) {
+  if (!src || !dest) {
+    throw new Error('Two arguments are required: <source> <destination>');
+  }
+
+  if (!fs.existsSync(src)) {
+    throw new Error(`Source file not found: ${src}`);
+  }
+
+  if (fs.statSync(src).isDirectory()) {
+    throw new Error(`Source is a directory, only files are supported: ${src}`);
+  }
+
+  const destEndsWithSlash = dest.endsWith('/');
+
+  let finalDest;
+
+  if (destEndsWithSlash) {
+    if (!fs.existsSync(dest) || !fs.statSync(dest).isDirectory()) {
+      throw new Error(`Destination directory does not exist: ${dest}`);
+    }
+    finalDest = path.join(dest, path.basename(src));
+  } else if (fs.existsSync(dest) && fs.statSync(dest).isDirectory()) {
+    finalDest = path.join(dest, path.basename(src));
+  } else {
+    const parentDir = path.dirname(dest);
+
+    if (
+      parentDir !== '.' &&
+      (!fs.existsSync(parentDir) || !fs.statSync(parentDir).isDirectory())
+    ) {
+      throw new Error(`Destination directory does not exist: ${parentDir}`);
+    }
+    finalDest = dest;
+  }
+
+  fs.renameSync(src, finalDest);
+}
+
+const [srcPath, destPath] = process.argv.slice(2);
+
+try {
+  moveFile(srcPath, destPath);
+} catch (err) {
+  process.stderr.write(`Error: ${err.message}\n`);
+}
+
+module.exports = { moveFile };