From c0593707f2d4677a2faef95d62f0c1a58dbf804e Mon Sep 17 00:00:00 2001
From: Elian Doran <contact@eliandoran.me>
Date: Thu, 26 Mar 2026 21:41:11 +0200
Subject: [PATCH] refactor(core): use own path replacement

---
 .../trilium-core/src/services/utils/index.ts  | 11 +++--
 .../src/services/utils/path.spec.ts           | 41 +++++++++++++++++++
 .../trilium-core/src/services/utils/path.ts   | 18 ++++++++
 3 files changed, 64 insertions(+), 6 deletions(-)
 create mode 100644 packages/trilium-core/src/services/utils/path.spec.ts
 create mode 100644 packages/trilium-core/src/services/utils/path.ts

diff --git a/packages/trilium-core/src/services/utils/index.ts b/packages/trilium-core/src/services/utils/index.ts
index b2f1188ee1..cd76e0325b 100644
--- a/packages/trilium-core/src/services/utils/index.ts
+++ b/packages/trilium-core/src/services/utils/index.ts
@@ -4,7 +4,7 @@ import { encodeBase64 } from "./binary";
 import { extensions as mimeToExt, types as extToMime } from "mime-types";
 import escape from "escape-html";
 import unescape from "unescape";
-import path from "path";
+import { basename, extname } from "./path";
 import { NoteMeta } from "../../meta";
 
 // TODO: Implement platform detection.
@@ -161,8 +161,7 @@ export function formatDownloadTitle(fileName: string, type: string | null, mime:
         if (mimeLc === "application/octet-stream") return "";
 
         // if fileName has an extension matching the mime already - reuse it
-        const dotIdx = fileName.lastIndexOf(".");
-        const ext = dotIdx !== -1 ? fileName.substring(dotIdx + 1).toLowerCase() : "";
+        const ext = extname(fileName).toLowerCase().replace(".", "");
         if (ext && extToMime[ext] === mimeLc) return "";
 
         // as last resort try to get extension from mimeType
@@ -207,7 +206,7 @@ export function escapeRegExp(str: string) {
 }
 
 export function removeFileExtension(filePath: string, mime?: string) {
-    const extension = path.extname(filePath).toLowerCase();
+    const extension = extname(filePath).toLowerCase();
 
     if (mime?.startsWith("video/") || mime?.startsWith("audio/")) {
         return filePath.substring(0, filePath.length - extension.length);
@@ -233,8 +232,8 @@ export function getNoteTitle(filePath: string, replaceUnderscoresWithSpaces: boo
     const trimmedNoteMeta = noteMeta?.title?.trim();
     if (trimmedNoteMeta) return trimmedNoteMeta;
 
-    const basename = path.basename(removeFileExtension(filePath, noteMeta?.mime));
-    return replaceUnderscoresWithSpaces ? basename.replace(/_/g, " ").trim() : basename;
+    const fileBasename = basename(removeFileExtension(filePath, noteMeta?.mime));
+    return replaceUnderscoresWithSpaces ? fileBasename.replace(/_/g, " ").trim() : fileBasename;
 }
 
 // try to turn 'true' and 'false' strings from process.env variables into boolean values or undefined
diff --git a/packages/trilium-core/src/services/utils/path.spec.ts b/packages/trilium-core/src/services/utils/path.spec.ts
new file mode 100644
index 0000000000..8543617def
--- /dev/null
+++ b/packages/trilium-core/src/services/utils/path.spec.ts
@@ -0,0 +1,41 @@
+import { describe, it, expect } from "vitest";
+import { extname, basename } from "./path";
+
+describe("#extname", () => {
+    const testCases: [input: string, expected: string][] = [
+        ["file.txt", ".txt"],
+        ["file.tar.gz", ".gz"],
+        ["file", ""],
+        [".hidden", ""],
+        [".hidden.txt", ".txt"],
+        ["no-ext.", "."],
+        ["path/to/file.ts", ".ts"],
+        ["path\\to\\file.ts", ".ts"],
+        ["path/to/.gitignore", ""],
+        ["", ""],
+    ];
+
+    testCases.forEach(([input, expected]) => {
+        it(`'${input}' should return '${expected}'`, () => {
+            expect(extname(input)).toBe(expected);
+        });
+    });
+});
+
+describe("#basename", () => {
+    const testCases: [input: string, expected: string][] = [
+        ["path/to/file.txt", "file.txt"],
+        ["path\\to\\file.txt", "file.txt"],
+        ["file.txt", "file.txt"],
+        ["/root/file", "file"],
+        ["C:\\Users\\test\\file.md", "file.md"],
+        ["path/to/dir/", ""],
+        ["", ""],
+    ];
+
+    testCases.forEach(([input, expected]) => {
+        it(`'${input}' should return '${expected}'`, () => {
+            expect(basename(input)).toBe(expected);
+        });
+    });
+});
diff --git a/packages/trilium-core/src/services/utils/path.ts b/packages/trilium-core/src/services/utils/path.ts
new file mode 100644
index 0000000000..d470b5dc16
--- /dev/null
+++ b/packages/trilium-core/src/services/utils/path.ts
@@ -0,0 +1,18 @@
+/**
+ * Browser-safe path utilities that don't depend on Node's `path` module.
+ * Handles both forward slashes and backslashes.
+ */
+
+/** Returns the extension of a file path (e.g. ".txt"), or "" if none. */
+export function extname(filePath: string): string {
+    const base = basename(filePath);
+    const dotIdx = base.lastIndexOf(".");
+    if (dotIdx <= 0) return "";
+    return base.substring(dotIdx);
+}
+
+/** Returns the last component of a file path. */
+export function basename(filePath: string): string {
+    const lastSlash = Math.max(filePath.lastIndexOf("/"), filePath.lastIndexOf("\\"));
+    return filePath.substring(lastSlash + 1);
+}