docs: update CLAUDE.md, README, and Vietnamese guide for migration step

- CLAUDE.md: document migrator.py algorithm and junction-removal rationale
- README.md: pipeline now 5 steps, add --skip-migrate flag, add migrator.py
  to folder structure, update test count 142 -> 158
- docs/huong-dan-su-dung.md: 5-step pipeline table, new glossary entry,
  updated footer version note

.gitignore

@@ -16,6 +16,13 @@ dist/
 build/
 .eggs/
 
+# Coverage
+.coverage
+*.cover
+*.py,cover
+htmlcov/
+coverage.xml
+
 # Virtual environments
 venv/
 .venv/

CLAUDE.md

@@ -92,7 +92,7 @@ Pass 2 builds `ok_disk_names` — the set of disk names that already match the s
 - `gui/app.py` — `ArmaModManagerApp` main window; manages view routing, config loading, thread-safe log queue, and background pipeline execution
 - `gui/wizard.py` — `SetupWizard` dialog shown on first launch when no `config.json` exists
 - `gui/_constants.py` — window dimensions, status color constants, file paths
-- `gui/_io.py` — `_QueueWriter` redirects stdout/stderr to a thread-safe queue so pipeline output streams into the Logs view
+- `gui/_io.py` — `_QueueWriter` redirects stdout/stderr to a thread-safe queue so pipeline output streams into the Logs view. `write()` strips ANSI/CSI escape codes and converts bare `\r` to `\n` before enqueuing, so `tqdm` progress output is legible in the textbox.
 
 **Views** (`gui/views/`): each inherits `BaseView`; `build()` runs once on creation, `refresh()` runs on each navigation:
 - `dashboard.py` — overview, status, quick stats
@@ -101,12 +101,75 @@ Pass 2 builds `ok_disk_names` — the set of disk names that already match the s
 - `logs.py` — real-time log viewer fed from the stdout/stderr queue
 - `settings.py` — in-app editor for `config.json` (server URL, paths, credentials)
 
+**`_find_folder` (mods.py) — four-level name matching:** The mods view resolves a mod's local folder by mod name from `comparison.json`, which may differ from the server-canonical folder name used by the fetcher. Lookup order:
+1. Exact: `@{mod_name}`
+2. Case-insensitive: `@CBA_A3` matches `CBA_A3`
+3. Normalized (`_normalize_name`): strips all non-alphanumeric — handles punctuation/spacing differences, e.g. `@US GEAr- Units (IFA3)` matches `US GEAr: Units (IFA3)` (both → `usgearunitsifa3`)
+4. Steam ID via `meta.cpp`: reads `publishedid` from each folder's `meta.cpp` and matches against `mod["steam_id"]` — handles the case where the folder name bears no resemblance to the modlist name but the mod content is correct
+
 **`selection.json`** — GUI selection state file, tracked in git. Persists which mods/groups are selected between GUI sessions. Written by the GUI; safe to delete (GUI recreates it on next save).
 
+**`run_tool` subprocess streaming:** Tool scripts are launched via `subprocess.Popen` (not `subprocess.run`) with `stdout=PIPE, stderr=STDOUT`, read line-by-line via `iter(proc.stdout.readline, "")`, and posted to the log queue immediately. Python's own output buffering is disabled with the `-u` flag and `PYTHONUNBUFFERED=1` in the environment — without these, output would batch inside the pipe and only appear when the script exits. The `Popen` call uses `encoding="utf-8", errors="replace"` and sets `PYTHONUTF8=1` in the child environment so that tqdm's Unicode block characters (e.g. `▉`) don't crash the pipe reader on Windows, where the default `charmap` codec cannot decode them.
+
+**GUI threading model:** Every network or long-running operation runs in a `threading.Thread(daemon=True)` so the Tkinter event loop is never blocked. The only safe way to update widgets from a background thread is `self.after(0, callback)` — never touch widgets directly from a worker thread. `_poll_log` drains the entire log queue in one `after(80, ...)` tick and does a single batched `CTkTextbox.insert()` call rather than one per log entry, keeping the UI smooth even when `tqdm` emits many rapid updates during downloads. The wizard's "Test Connection" button follows the same pattern: `requests.get` runs in a daemon thread; the result is posted back via `self.after(0, ...)` with widget references captured *before* the thread starts, so stale references cannot update the wrong widgets if the user navigates away mid-request.
+
+**`run_pipeline` worker — import guard:** `from run import step_fetch, step_link` is performed inside its own `try/except` *before* stdout is redirected. If this import fails for any reason the exception is posted to the log via `self.after(0, ...)` and `_pipeline_done` is called so the UI resets cleanly. Previously an import failure would silently kill the worker thread and leave the pipeline button disabled forever.
+
+**`build_server_index` progress callback:** Accepts an optional `progress_fn(current, total, name)` callback. `step_fetch` in `run.py` uses this to print `Indexing N/M: @FolderName` every 25 folders so the log never goes silent during the server scan phase. The library itself never calls `print` — the caller owns the I/O.
+
+### `migrator.py` — mod group migration
+
+Before `step_fetch` runs, `step_migrate` moves locally-downloaded mod folders to match the group assignments in the new `comparison.json`. This avoids re-downloading mods that already exist on disk under a different group when presets are switched (e.g. `A` → `A_v1`).
+
+**Algorithm:**
+
+1. `_build_local_index(downloads)` — scans every `downloads/{group}/@Folder`, reads `meta.cpp` to extract `publishedid`, builds `{steam_id → (group, path)}` and `{norm_name → (group, path)}` maps.
+2. `_build_target_list(comparison)` — flattens `comparison.json` into `[(new_group, steam_id, mod_name)]`.
+3. For each target: locate mod on disk (steam_id first, normalised name fallback); skip if already in correct group or destination exists; remove stale junction from `arma_dir` if present; move folder with `shutil.move`.
+
+**Junction removal is critical:** a stale junction (target moved away) still has the reparse point attribute, so `_is_junction()` returns `True` and `link_group` would skip it as `already_linked` without recreating it at the new path. Removing the junction before the move lets `step_link` recreate it correctly.
+
+**CLI:** `python run.py --skip-migrate` bypasses the step if needed.
+
+### `update_mods.py` — orphan file removal
+
+After downloading updated files, `update_mods.py` compares every file in the local mod folder against the server's file list and **deletes any local files that no longer exist on the server**. This prevents stale `.pbo` or `.bisign` files from accumulating when a mod's content changes upstream. Each removed file is logged as `[-] orphan removed: <rel_path>` and the final summary line includes an orphan count. The orphan check runs even when no files need downloading (e.g. timestamps match but the local folder has extras).
+
+### GUI localization (`gui/locales.py`)
+
+All user-facing strings are centralised in `gui/locales.py`. Two languages are supported: English (`"en"`) and Vietnamese (`"vi"`).
+
+**API:**
+```python
+from gui.locales import t, set_language, get_language
+
+t("nav.dashboard")                          # → "Dashboard" or "Tổng quan"
+t("dashboard.stats", total=42, shared=10)   # → "42 mods · 10 shared"
+set_language("vi")                          # switch active language
+get_language()                              # → "vi"
+```
+
+**Key naming:** flat dot-notation — `"<view>.<widget_purpose>"`, e.g. `"dashboard.run_btn"`, `"wizard.step1_title"`, `"tools.cn_warn"`.
+
+**Dynamic strings** use `str.format_map` with keyword args. The dict value contains `{placeholder}` and the caller passes `t("key", placeholder=value)`.
+
+**Hot-swap:** `app.switch_language(lang)` calls `set_language()`, saves the preference to `config.json` under `"ui": {"language": "..."}`, retranslates sidebar nav buttons, then calls `view.refresh()` on every cached view. Views that build all content in `refresh()` (Settings, Mods) update automatically. Views with static `build()`-time widgets (Dashboard, Logs, Tools) store widget references and retranslate them at the top of `refresh()`.
+
+**Constraints:**
+- `CTkTabview` tab names in `tools.py` are kept in English — they double as frame lookup keys (`tv.tab("Check Names")`) and cannot be renamed after creation.
+- Segmented button values in `tools.py` (`"Status"`, `"Link"`, `"Unlink"`) are kept in English — they drive the logic in `_lm_on_change()`.
+- `_VIEW_NAMES` routing keys (`"Dashboard"`, `"Mods"`, etc.) are kept in English — they are `_view_cache` dict keys.
+
+**Adding a new string:** Add the key to both `_EN` and `_VI` dicts in `locales.py`. The `assert set(_EN.keys()) == set(_VI.keys())` guard at module load will catch any mismatch.
+
 ## Python Version Compatibility
 
 Minimum is Python **3.9**. All files that use `X | Y` union type annotations **must** have `from __future__ import annotations` as the first import. Without it, the `|` syntax raises `TypeError` at runtime on Python < 3.10. Every module in `arma_modlist_tools/` already has it; any new CLI script you add must include it too.
 
+### `fix_console_encoding` — `None` stdout guard
+
+When the GUI is launched via `pythonw.exe` (no console window), Python sets `sys.stdout` and `sys.stderr` to `None`. `fix_console_encoding()` must check `if sys.stdout is None or sys.stderr is None: return` **before** accessing `.encoding`, otherwise it raises `AttributeError: 'NoneType' object has no attribute 'encoding'`. This error surfaces in the GUI as *"Failed to load pipeline"* because `run.py` calls `fix_console_encoding()` at module level and the exception is caught by the pipeline import guard.
+
 ## Test Suite
 
 `test_suite.py` uses a custom harness (no pytest/unittest dependency). Structure:

README.md

@@ -4,6 +4,31 @@ Python toolchain for managing Arma 3 mod presets: parse launcher exports, compar
 
 ---
 
+## Quick Reference
+
+```bash
+# First time setup
+cp config.template.json config.json   # fill in server URL + credentials + arma_dir
+python check_deps.py                  # verify dependencies
+
+# Day-to-day: full pipeline
+python run.py                         # parse → compare → migrate → download → link
+
+# GUI (recommended)
+python gui.py
+
+# Maintenance
+python clean_orphans.py --dry-run     # find stale mod folders from old presets
+python update_mods.py                 # re-download changed files (size-check)
+python sync_missing.py                # retry mods that were absent from server
+python check_names.py --fix           # fix folder name mismatches
+
+# Testing
+python test_suite.py                  # 158 tests (network tests auto-skip if offline)
+```
+
+---
+
 ## Table of Contents
 
 1. [Prerequisites](#prerequisites)
@@ -20,6 +45,7 @@ Python toolchain for managing Arma 3 mod presets: parse launcher exports, compar
    - [sync_missing.py](#sync_missingpy)
    - [update_mods.py](#update_modspy)
    - [check_names.py](#check_namespy)
+   - [clean_orphans.py](#clean_orphanspy)
    - [run.py](#runpy)
    - [gui.py](#guipy)
 6. [Migrating Existing Mods](#migrating-existing-mods)
@@ -107,29 +133,34 @@ Place your Arma 3 Launcher preset exports (`.html`) into the `modlist_html/` fol
 python run.py
 ```
 
-This runs all four steps in sequence:
+This runs all five steps in sequence:
 
 ```
-Step 1/4: Parse presets       — modlist_html/*.html  ->  modlist_json/*.json
-Step 2/4: Compare presets     — produces modlist_json/comparison.json
-Step 3/4: Fetch mods          — downloads from server  ->  downloads/
-Step 4/4: Link mods           — creates junctions/symlinks in Arma 3 Server dir
+Step 1/5: Parse presets       — modlist_html/*.html  ->  modlist_json/*.json
+Step 2/5: Compare presets     — produces modlist_json/comparison.json
+Step 3/5: Migrate mod groups  — moves existing folders to match new group assignments
+Step 4/5: Fetch mods          — downloads from server  ->  downloads/
+Step 5/5: Link mods           — creates junctions/symlinks in Arma 3 Server dir
 ```
 
+The **migrate step** avoids re-downloading mods that already exist on disk when you switch preset versions (e.g. `A` → `A_v1`). It matches mods by steam ID (via `meta.cpp`) and moves the folder to the correct group, removing any stale junction first so the link step can re-create it at the new path.
+
 ### Skip flags
 
 ```bash
-python run.py --skip-fetch --skip-link          # parse + compare only
+python run.py --skip-fetch --skip-link                    # parse + compare + migrate only
 python run.py --skip-parse --skip-compare --skip-fetch    # link only
 python run.py --skip-parse --skip-compare --skip-fetch --group shared
+python run.py --skip-migrate                              # skip auto-migration
 ```
 
 | Flag | Skips |
 |------|-------|
 | `--skip-parse` | Step 1 (HTML parsing) |
 | `--skip-compare` | Step 2 (preset comparison) |
-| `--skip-fetch` | Step 3 (downloading) |
-| `--skip-link` | Step 4 (linking) |
+| `--skip-migrate` | Step 3 (mod group migration) |
+| `--skip-fetch` | Step 4 (downloading) |
+| `--skip-link` | Step 5 (linking) |
 | `--group GROUP` | Link step: only link this one group (e.g. `shared`) |
 
 > **Safe to re-run.** Every step is idempotent — existing files are skipped, already-linked mods are skipped.
@@ -468,9 +499,39 @@ python check_names.py --fix --fix-ids
 
 ---
 
+### clean_orphans.py
+
+Find and optionally delete orphaned mod folders — `downloads/{group}/@ModName` folders that are no longer referenced in `comparison.json`. These accumulate when you switch presets and re-run the pipeline without cleaning up old downloads.
+
+```bash
+python clean_orphans.py               # list orphans, prompt for confirmation
+python clean_orphans.py --dry-run     # list orphans, do not delete
+python clean_orphans.py --yes         # list and delete without prompting
+```
+
+```
+  Group                         Folder                            Size
+  ----------------------------  --------------------------------  ----------
+  shared                        @OldMod                           124.5 MB
+  150th_WW2_2026_V1.0           @SomeMod                          88.2 MB
+
+  2 orphan(s) found — 212.7 MB total
+
+  Delete all orphans? [y/N]
+```
+
+- Matches by normalized name (same logic as the fetcher), so spacing/capitalization differences are handled correctly
+- Junction-safe: uses `os.rmdir()` on junctions rather than `shutil.rmtree` to avoid deleting target files
+
+**Requires:** `modlist_json/comparison.json` (run `run.py --skip-fetch --skip-link` first).
+
+The same functionality is available as the **Clean Orphans** tab in the GUI.
+
+---
+
 ### run.py
 
-Orchestrator that chains all four pipeline steps. Described in [Quick Start](#quick-start--full-pipeline) above.
+Orchestrator that chains all five pipeline steps. Described in [Quick Start](#quick-start--full-pipeline) above.
 
 ---
 
@@ -488,10 +549,12 @@ Opens a CustomTkinter desktop window with a sidebar navigation and the following
 |------|---------|
 | Dashboard | Overview: status, quick stats, recent activity |
 | Mods | Browse and manage downloaded mods by group |
-| Tools | Link/unlink, rename, sync missing, check server |
+| Tools | Link/unlink, rename, sync missing, check server, **clean orphans** |
 | Logs | Real-time log output from pipeline operations |
 | Settings | Edit `config.json` (server URL, paths, credentials) |
 
+The **Tools** view has five tabs: Check Names, Update Mods, Link Mods, Sync Missing / Report Missing, and **Clean Orphans** (find and delete stale mod folders from old presets).
+
 On first launch (no `config.json`), a setup wizard walks you through creating one.
 
 **Requires:** `customtkinter` (`pip install customtkinter`).
@@ -543,6 +606,8 @@ arma-modlist-tools/
 |   |- fetcher.py             # Caddy server downloader
 |   |- linker.py              # Junction/symlink manager
 |   |- reporter.py            # Missing-mod report builder
+|   |- cleaner.py             # Orphan folder detection
+|   |- migrator.py            # Mod group migration (move folders to match comparison.json)
 |   |- config.py              # config.json loader
 |   |- compat.py              # OS detection + encoding fix
 |
@@ -591,8 +656,9 @@ arma-modlist-tools/
 |- sync_missing.py            # Sync newly available missing mods
 |- update_mods.py             # Re-download updated mod files
 |- check_names.py             # Diagnose and fix folder name / steam_id issues
+|- clean_orphans.py           # Find and delete orphaned mod folders
 |- check_deps.py              # Dependency checker
-|- test_suite.py              # Test suite
+|- test_suite.py              # Test suite (158 tests)
 ```
 
 ---
@@ -631,7 +697,7 @@ arma-modlist-tools/
 
 ## Running Tests
 
-The test suite covers all modules with 85 tests. No network connection required.
+The test suite covers all modules with 158 tests. Network tests auto-skip when the server is unreachable.
 
 ```bash
 python test_suite.py
@@ -639,16 +705,23 @@ python test_suite.py
 
 ```
 ------------------------------------------------------------
-  compat            6 tests
+  compat              11 tests
   config               5 tests
   parser               9 tests
   compare              8 tests
-  fetcher          19 tests   (pure functions, no network)
+  fetcher             24 tests   (pure functions + mock)
   reporter             8 tests
   linker              12 tests   (uses temp dirs)
   __init__             2 tests
   check_names         16 tests
   integration          2 tests
+  gui._io             11 tests   (QueueWriter, no GUI required)
+  cleaner              8 tests
+  e2e — clean_orphans  6 tests   (subprocess CLI)
+  coverage gaps       23 tests   (mocked platform branches)
+  gui.views.mods       8 tests   (_find_folder matching)
+  migrator             7 tests   (group migration logic)
+  live server          9 tests   (skipped if server unreachable)
 ------------------------------------------------------------
-  Results: 85 passed, 0 failed, 0 skipped  (85 total)
+  Results: 158 passed, 0 failed, 0 skipped  (158 total)
 ```

arma_modlist_tools/__init__.py

@@ -11,6 +11,8 @@ from .linker import (
 from .config  import load_config, Config
 from .compat  import is_windows, is_linux, get_os_label, fix_console_encoding
 from .reporter import build_missing_report, save_missing_report
+from .cleaner  import find_orphan_folders, folder_size
+from .migrator import migrate_mod_groups
 
 __all__ = [
     # parser
@@ -29,4 +31,8 @@ __all__ = [
     "is_windows", "is_linux", "get_os_label", "fix_console_encoding",
     # reporter
     "build_missing_report", "save_missing_report",
+    # cleaner
+    "find_orphan_folders", "folder_size",
+    # migrator
+    "migrate_mod_groups",
 ]

arma_modlist_tools/cleaner.py

@@ -0,0 +1,80 @@
+"""
+arma_modlist_tools.cleaner
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+Identify orphaned mod folders in the downloads directory.
+
+An *orphan* is a downloaded ``@ModName`` folder that is no longer referenced
+by any group in ``comparison.json``.  This happens when the user swaps out a
+modlist preset and re-runs the compare step — mods that were removed from the
+preset remain on disk but are no longer tracked.
+
+Typical usage::
+
+    from arma_modlist_tools.cleaner import find_orphan_folders
+
+    comparison = json.loads(Path("modlist_json/comparison.json").read_text())
+    orphans    = find_orphan_folders(Path("downloads"), comparison)
+    for o in orphans:
+        print(o["group"], o["name"], o["size"])
+"""
+from __future__ import annotations
+
+from pathlib import Path
+
+from .fetcher import _normalize_name as _normalize
+
+
+def folder_size(path: Path) -> int:
+    """Return the total size in bytes of all files under *path* (recursive)."""
+    return sum(f.stat().st_size for f in path.rglob("*") if f.is_file())
+
+
+def find_orphan_folders(
+    downloads: Path,
+    comparison: dict,
+) -> list[dict]:
+    """Return a list of orphan mod folder entries.
+
+    A folder ``downloads/{group}/@ModName`` is considered an orphan when its
+    normalised name does not match any mod in *comparison* under the same
+    group.  Groups in ``downloads/`` that do not exist in *comparison* at all
+    are treated as entirely orphaned.
+
+    :param downloads:  Path to the ``downloads/`` directory.
+    :param comparison: Parsed ``comparison.json`` dict (output of
+                       :func:`~arma_modlist_tools.compare.compare_presets`).
+    :returns: List of dicts, each with:
+
+              - ``path``  — absolute :class:`~pathlib.Path` of the folder
+              - ``group`` — group name (e.g. ``"shared"``)
+              - ``name``  — folder name as it appears on disk (e.g. ``"@ace"``)
+              - ``size``  — total size in bytes (recursive)
+    """
+    # Build group → set-of-normalised-mod-names from comparison data
+    known: dict[str, set[str]] = {}
+    for mod in comparison.get("shared", {}).get("mods", []):
+        known.setdefault("shared", set()).add(_normalize(mod["name"]))
+    for preset, pdata in comparison.get("unique", {}).items():
+        for mod in pdata.get("mods", []):
+            known.setdefault(preset, set()).add(_normalize(mod["name"]))
+
+    orphans: list[dict] = []
+    if not downloads.is_dir():
+        return orphans
+
+    for group_dir in sorted(downloads.iterdir()):
+        if not group_dir.is_dir():
+            continue
+        group_known = known.get(group_dir.name, set())  # empty → group removed
+        for mod_dir in sorted(group_dir.iterdir()):
+            if not mod_dir.is_dir() or not mod_dir.name.startswith("@"):
+                continue
+            if _normalize(mod_dir.name) not in group_known:
+                orphans.append({
+                    "path":  mod_dir,
+                    "group": group_dir.name,
+                    "name":  mod_dir.name,
+                    "size":  folder_size(mod_dir),
+                })
+
+    return orphans

arma_modlist_tools/compat.py

@@ -102,6 +102,8 @@ def fix_console_encoding() -> None:
     """
     if not is_windows():
         return
+    if sys.stdout is None or sys.stderr is None:
+        return
     if sys.stdout.encoding and sys.stdout.encoding.lower() == "utf-8":
         return
     sys.stdout = io.TextIOWrapper(sys.stdout.buffer, encoding="utf-8", errors="replace")

arma_modlist_tools/fetcher.py

@@ -81,7 +81,11 @@ def make_session(auth: tuple[str, str]) -> requests.Session:
     return s
 
 
-def build_server_index(base_url: str, auth: tuple[str, str]) -> dict:
+def build_server_index(
+    base_url: str,
+    auth: tuple[str, str],
+    progress_fn: "Callable[[int, int, str], None] | None" = None,
+) -> dict:
     """
     Scan the root of the file server and build mod lookup maps.
 
@@ -90,6 +94,9 @@ def build_server_index(base_url: str, auth: tuple[str, str]) -> dict:
 
     :param base_url: Root URL of the Caddy file server (trailing slash optional).
     :param auth: ``(username, password)`` tuple for HTTP Basic Auth.
+    :param progress_fn: Optional callback called as ``progress_fn(current, total, name)``
+                        after each folder is processed.  Use it to report progress without
+                        coupling the library to ``print`` or any specific I/O sink.
     :returns: Dict with keys:
 
               - ``by_steam_id`` — ``{steam_id: folder_url}``
@@ -100,11 +107,12 @@ def build_server_index(base_url: str, auth: tuple[str, str]) -> dict:
     root = base_url.rstrip("/") + "/"
     items = _list_dir(root, session)
     folders = [it for it in items if it.get("is_dir")]
+    total = len(folders)
 
     by_steam_id: dict[str, str] = {}
     by_name: dict[str, str] = {}
 
-    for folder in folders:
+    for i, folder in enumerate(folders, 1):
         name = folder["name"].strip("/")
         url = _folder_url(root, name)
         by_name[_normalize_name(name)] = url
@@ -118,6 +126,9 @@ def build_server_index(base_url: str, auth: tuple[str, str]) -> dict:
         except requests.RequestException:
             pass  # meta.cpp missing or unreachable — name-based fallback still works
 
+        if progress_fn is not None:
+            progress_fn(i, total, name)
+
     return {"by_steam_id": by_steam_id, "by_name": by_name, "folders": folders}
 
 

arma_modlist_tools/migrator.py

@@ -0,0 +1,186 @@
+"""
+arma_modlist_tools.migrator
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Move locally-downloaded mod folders to match the group assignments in
+comparison.json, avoiding redundant re-downloads when presets are renamed
+or reorganised.
+
+A mod "needs migration" when it exists on disk under
+``downloads/{old_group}/@FolderName`` but comparison.json now assigns it
+to ``downloads/{new_group}/@FolderName``.
+
+Algorithm
+---------
+1. Build a *local index*: scan every ``downloads/{group}/@ModDir`` and read
+   its ``meta.cpp`` to find its steam_id.  Also record its normalised folder
+   name.  Result: ``{steam_id: (group, path)}`` and
+   ``{norm_name: (group, path)}``.
+
+2. Build a *target list* from comparison.json: for every mod in every group,
+   record which group comparison now assigns it to.
+
+3. For each target entry:
+   - Find the mod in the local index (steam_id first, normalised name fallback).
+   - If not found on disk: skip (step_fetch will download it).
+   - If already in the correct group: skip.
+   - If the destination already exists: skip (step_fetch handles file-level sync).
+   - Otherwise: remove any stale junction first, then move old → new.
+"""
+from __future__ import annotations
+
+import shutil
+from pathlib import Path
+
+from .fetcher import _normalize_name, _parse_meta_cpp
+from .linker  import _is_junction, remove_junction
+
+
+def _build_local_index(downloads: Path) -> dict:
+    """Scan ``downloads/`` and return a two-key index of existing mod folders.
+
+    :returns: ``{"by_steam_id": {sid: (group, path)},
+                 "by_norm_name": {norm: (group, path)}}``
+
+    First match wins for both keys (sorted directory order is deterministic).
+    """
+    by_steam_id:  dict[str, tuple[str, Path]] = {}
+    by_norm_name: dict[str, tuple[str, Path]] = {}
+
+    if not downloads.is_dir():
+        return {"by_steam_id": by_steam_id, "by_norm_name": by_norm_name}
+
+    for group_dir in sorted(downloads.iterdir()):
+        if not group_dir.is_dir():
+            continue
+        group_name = group_dir.name
+        for mod_dir in sorted(group_dir.iterdir()):
+            if not mod_dir.is_dir() or not mod_dir.name.startswith("@"):
+                continue
+
+            norm = _normalize_name(mod_dir.name)
+            if norm not in by_norm_name:
+                by_norm_name[norm] = (group_name, mod_dir)
+
+            meta = mod_dir / "meta.cpp"
+            if meta.exists():
+                try:
+                    sid = _parse_meta_cpp(
+                        meta.read_text(encoding="utf-8", errors="replace")
+                    )
+                    if sid and sid not in by_steam_id:
+                        by_steam_id[sid] = (group_name, mod_dir)
+                except OSError:
+                    pass
+
+    return {"by_steam_id": by_steam_id, "by_norm_name": by_norm_name}
+
+
+def _build_target_list(comparison: dict) -> list[tuple[str, str | None, str]]:
+    """Flatten comparison.json into ``[(new_group, steam_id_or_None, mod_name)]``.
+
+    Shared mods → group ``"shared"``; unique mods → group = preset name.
+    """
+    entries: list[tuple[str, str | None, str]] = []
+    for mod in comparison.get("shared", {}).get("mods", []):
+        entries.append(("shared", mod.get("steam_id") or None, mod.get("name", "")))
+    for preset, pdata in comparison.get("unique", {}).items():
+        for mod in pdata.get("mods", []):
+            entries.append((preset, mod.get("steam_id") or None, mod.get("name", "")))
+    return entries
+
+
+def migrate_mod_groups(
+    downloads: Path,
+    arma_dir: Path | None,
+    comparison: dict,
+) -> dict:
+    """Move locally-downloaded mod folders to match *comparison* group assignments.
+
+    :param downloads:   Path to the ``downloads/`` directory.
+    :param arma_dir:    Path to the Arma 3 server directory used for junction
+                        cleanup.  Pass ``None`` to skip junction removal.
+    :param comparison:  Parsed ``comparison.json`` dict.
+    :returns: Result dict::
+
+                {
+                  "moved":               int,
+                  "junction_removed":    int,
+                  "skipped_correct":     int,
+                  "skipped_dest_exists": int,
+                  "skipped_not_found":   int,
+                  "errors":              {mod_name: error_message},
+                }
+    """
+    result: dict = {
+        "moved": 0,
+        "junction_removed": 0,
+        "skipped_correct": 0,
+        "skipped_dest_exists": 0,
+        "skipped_not_found": 0,
+        "errors": {},
+    }
+
+    local = _build_local_index(downloads)
+
+    for new_group, steam_id, mod_name in _build_target_list(comparison):
+        # 1. Locate on disk — steam_id first, normalised name fallback
+        entry: tuple[str, Path] | None = None
+        if steam_id:
+            entry = local["by_steam_id"].get(steam_id)
+        if entry is None:
+            entry = local["by_norm_name"].get(_normalize_name(mod_name))
+
+        if entry is None:
+            result["skipped_not_found"] += 1
+            continue
+
+        old_group, old_path = entry
+
+        # 2. Already in the correct group?
+        if old_group == new_group:
+            result["skipped_correct"] += 1
+            continue
+
+        # 3. Destination already present — let step_fetch handle file-level sync
+        new_path = downloads / new_group / old_path.name
+        if new_path.exists():
+            result["skipped_dest_exists"] += 1
+            continue
+
+        # 4. Remove stale junction so step_link can re-create it at the new path
+        if arma_dir is not None and arma_dir.is_dir():
+            link = arma_dir / old_path.name
+            if _is_junction(link):
+                ok, err = remove_junction(link)
+                if ok:
+                    result["junction_removed"] += 1
+                else:
+                    print(f"  MIGRATE WARNING: cannot remove junction "
+                          f"{link.name}: {err}")
+
+        # 5. Move folder (shutil.move handles cross-device gracefully)
+        try:
+            new_path.parent.mkdir(parents=True, exist_ok=True)
+            shutil.move(str(old_path), str(new_path))
+            print(f"  MIGRATE moved: {old_path.name}  {old_group} -> {new_group}")
+            result["moved"] += 1
+
+            # Update index so later targets don't re-match the now-moved path
+            if steam_id:
+                local["by_steam_id"][steam_id] = (new_group, new_path)
+            local["by_norm_name"][_normalize_name(old_path.name)] = (
+                new_group, new_path
+            )
+
+        except OSError as exc:
+            print(f"  MIGRATE ERROR: {old_path.name}: {exc}")
+            result["errors"][mod_name] = str(exc)
+
+    print(
+        f"  Moved: {result['moved']}  "
+        f"Junctions removed: {result['junction_removed']}  "
+        f"Already correct: {result['skipped_correct']}  "
+        f"Dest exists: {result['skipped_dest_exists']}  "
+        f"Not on disk: {result['skipped_not_found']}"
+    )
+    return result

clean_orphans.py

@@ -0,0 +1,127 @@
+#!/usr/bin/env python3
+"""
+CLI entry point: find and remove orphaned mod folders from downloads/.
+
+An orphan is a downloads/{group}/@ModName folder that is no longer referenced
+by any group in comparison.json.  These accumulate when presets change and
+the pipeline is re-run without cleaning up old folders.
+
+Usage:
+    python clean_orphans.py               # list orphans, ask for confirmation
+    python clean_orphans.py --dry-run     # list orphans, do not delete
+    python clean_orphans.py --yes         # list and delete without prompting
+"""
+from __future__ import annotations
+
+import argparse
+import json
+import os
+import shutil
+import sys
+
+from arma_modlist_tools.cleaner import find_orphan_folders
+from arma_modlist_tools.compat import fix_console_encoding
+from arma_modlist_tools.config import load_config
+from arma_modlist_tools.linker import _is_junction, remove_junction
+
+fix_console_encoding()
+
+_UNITS = ("B", "KB", "MB", "GB", "TB")
+
+
+def _fmt_size(n: int) -> str:
+    for unit in _UNITS:
+        if n < 1024:
+            return f"{n:.1f} {unit}"
+        n /= 1024
+    return f"{n:.1f} PB"
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser(
+        description="Find and remove orphaned mod folders from downloads/."
+    )
+    parser.add_argument(
+        "--dry-run",
+        action="store_true",
+        help="List orphans but do not delete anything.",
+    )
+    parser.add_argument(
+        "--yes", "-y",
+        action="store_true",
+        help="Delete without prompting for confirmation.",
+    )
+    args = parser.parse_args()
+
+    cfg = load_config()
+
+    if not cfg.comparison.exists():
+        print(f"ERROR: {cfg.comparison} not found. Run compare_modlists.py first.")
+        sys.exit(1)
+
+    comparison = json.loads(cfg.comparison.read_text(encoding="utf-8"))
+
+    print(f"\nScanning {cfg.downloads} for orphaned mod folders...\n")
+    orphans = find_orphan_folders(cfg.downloads, comparison)
+
+    if not orphans:
+        print("  No orphans found. Your downloads folder is clean.")
+        print()
+        return
+
+    total_size = sum(o["size"] for o in orphans)
+    print(f"  {'Group':<28}  {'Folder':<32}  Size")
+    print(f"  {'-'*28}  {'-'*32}  {'-'*10}")
+    for o in orphans:
+        print(f"  {o['group']:<28}  {o['name']:<32}  {_fmt_size(o['size'])}")
+
+    print()
+    print(f"  {len(orphans)} orphan(s) found — {_fmt_size(total_size)} total")
+    print()
+
+    if args.dry_run:
+        print("  --dry-run: nothing deleted.")
+        print()
+        return
+
+    if not args.yes:
+        answer = input("  Delete all orphans? [y/N] ").strip().lower()
+        if answer not in ("y", "yes"):
+            print("  Aborted.")
+            print()
+            return
+
+    deleted = 0
+    freed = 0
+    errors = 0
+    for o in orphans:
+        p = o["path"]
+        try:
+            if _is_junction(p):
+                # Safety: never rmtree a junction — use remove_junction() which
+                # calls os.rmdir() and removes only the pointer, not the target.
+                ok, err = remove_junction(p)
+                if not ok:
+                    print(f"  ERROR: could not remove junction {p.name}: {err}")
+                    errors += 1
+                    continue
+            else:
+                shutil.rmtree(p)
+            deleted += 1
+            freed += o["size"]
+            print(f"  Deleted: {o['group']}/{o['name']}")
+        except Exception as e:
+            print(f"  ERROR: {p.name}: {e}")
+            errors += 1
+
+    print()
+    print(f"  Done: {deleted} deleted, freed {_fmt_size(freed)}"
+          + (f", {errors} error(s)" if errors else ""))
+    print()
+
+    if errors:
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    main()

docs/huong-dan-su-dung.md

@@ -0,0 +1,412 @@
+# Hướng dẫn sử dụng Arma Mod Manager
+
+Tài liệu này dành cho người dùng **chưa biết gì** về dự án. Bạn không cần kiến thức lập trình để sử dụng ứng dụng này.
+
+---
+
+## Mục lục
+
+1. [Arma Mod Manager là gì?](#1-arma-mod-manager-là-gì)
+2. [Yêu cầu hệ thống](#2-yêu-cầu-hệ-thống)
+3. [Khởi động lần đầu — Trình thiết lập](#3-khởi-động-lần-đầu--trình-thiết-lập)
+4. [Giao diện chính](#4-giao-diện-chính)
+5. [Tổng quan (Dashboard) — Quy trình cơ bản](#5-tổng-quan-dashboard--quy-trình-cơ-bản)
+6. [Danh sách Mod](#6-danh-sách-mod)
+7. [Công cụ nâng cao](#7-công-cụ-nâng-cao)
+   - [Check Names](#tab-check-names--kiểm-tra-tên-thư-mục)
+   - [Update Mods](#tab-update-mods--cập-nhật-mod)
+   - [Link Mods](#tab-link-mods--quản-lý-liên-kết)
+   - [Sync / Report Missing](#tab-sync-missing--đồng-bộ-mod-thiếu)
+   - [Clean Orphans](#tab-clean-orphans--dọn-dẹp-mod-thừa)
+8. [Nhật ký (Logs)](#8-nhật-ký-logs)
+9. [Cài đặt](#9-cài-đặt)
+10. [Đổi sang giao diện tiếng Việt](#10-đổi-sang-giao-diện-tiếng-việt)
+11. [Xử lý sự cố thường gặp](#11-xử-lý-sự-cố-thường-gặp)
+12. [Bảng thuật ngữ](#12-bảng-thuật-ngữ)
+
+---
+
+## 1. Arma Mod Manager là gì?
+
+**Arma Mod Manager** là công cụ giúp bạn tải về và quản lý các mod cho **Arma 3 Server** từ một máy chủ lưu trữ riêng (Caddy server). Thay vì tải từng mod thủ công, bạn chỉ cần:
+
+1. Xuất danh sách mod từ Arma 3 Launcher dưới dạng tệp HTML (gọi là **preset**)
+2. Chọn preset trong ứng dụng
+3. Nhấn nút **Chạy toàn bộ quy trình**
+
+Ứng dụng sẽ tự động:
+- Đọc danh sách mod từ các preset
+- So sánh, tìm mod dùng chung và mod riêng giữa các preset
+- **Di chuyển** các thư mục mod đã tải về sang đúng nhóm mới (tránh tải lại khi đổi phiên bản preset)
+- Tải mod từ máy chủ về máy tính của bạn (chỉ những mod thực sự chưa có)
+- Tạo liên kết (junction/symlink) để Arma 3 Server nhận ra các mod
+
+---
+
+## 2. Yêu cầu hệ thống
+
+| Yêu cầu | Thông tin |
+|---------|-----------|
+| Hệ điều hành | Windows 10/11 (64-bit) |
+| Python | 3.9 trở lên |
+| Arma 3 Server | Đã cài đặt trên máy |
+| Kết nối mạng | Cần thiết để tải mod từ máy chủ |
+
+**Cài đặt thư viện cần thiết** (chỉ cần làm một lần):
+
+Mở Command Prompt, điều hướng tới thư mục ứng dụng, chạy:
+
+```
+pip install -r requirements.txt
+```
+
+---
+
+## 3. Khởi động lần đầu — Trình thiết lập
+
+Khi khởi động ứng dụng lần đầu (chưa có tệp `config.json`), cửa sổ **Thiết lập** sẽ tự động hiện ra gồm 3 bước:
+
+### Bước 1 / 3 — Kết nối máy chủ
+
+![Bước 1](placeholder)
+
+| Trường | Mô tả |
+|--------|-------|
+| **URL máy chủ** | Địa chỉ đầy đủ của máy chủ Caddy lưu mod, ví dụ: `https://mods.example.com/` |
+| **Tên đăng nhập** | Tài khoản được cấp bởi người quản trị máy chủ |
+| **Mật khẩu** | Mật khẩu tương ứng |
+
+- Nhấn **Kiểm tra kết nối** để xác nhận thông tin trước khi tiếp tục.
+  - `✓ Đã kết nối` — thành công, nhấn **Tiếp theo →**
+  - `✗ HTTP 401` — sai tên đăng nhập hoặc mật khẩu
+  - `✗ ...` — lỗi mạng hoặc URL sai
+
+### Bước 2 / 3 — Thư mục Arma 3 Server
+
+Nhấn **Duyệt** để chọn thư mục gốc của Arma 3 Server trên máy tính (thư mục chứa `arma3server.exe`).
+
+> Ví dụ: `C:\servers\arma3`
+
+Các thư mục khác (downloads, presets) sẽ tự động được tạo bên cạnh ứng dụng.
+
+### Bước 3 / 3 — Xem lại & Lưu
+
+Kiểm tra thông tin đã nhập rồi nhấn **Lưu & Mở**. Ứng dụng sẽ lưu cấu hình và mở giao diện chính.
+
+> **Mẹo:** Để mở lại trình thiết lập bất cứ lúc nào, vào **Cài đặt → Mở trình thiết lập**.
+
+---
+
+## 4. Giao diện chính
+
+Giao diện gồm thanh điều hướng bên trái và khu vực nội dung bên phải.
+
+```
+┌─────────────────┬──────────────────────────────────┐
+│  Arma Mod       │                                  │
+│  Manager        │   Khu vực nội dung               │
+│─────────────────│   (thay đổi theo mục chọn)       │
+│  Tổng quan      │                                  │
+│  Danh sách Mod  │                                  │
+│  Công cụ        │                                  │
+│  Nhật ký        │                                  │
+│  Cài đặt        │                                  │
+└─────────────────┴──────────────────────────────────┘
+```
+
+| Mục | Chức năng |
+|-----|-----------|
+| **Tổng quan** | Chọn preset, xem trạng thái pipeline, chạy quy trình tải mod |
+| **Danh sách Mod** | Xem tất cả mod theo nhóm, trạng thái tải/liên kết/máy chủ |
+| **Công cụ** | Các tác vụ bảo trì nâng cao |
+| **Nhật ký** | Xem toàn bộ output của pipeline và công cụ |
+| **Cài đặt** | Cấu hình giao diện, ngôn ngữ, mở lại trình thiết lập |
+
+---
+
+## 5. Tổng quan (Dashboard) — Quy trình cơ bản
+
+Đây là trang chính bạn sẽ dùng thường xuyên nhất.
+
+### 5.1 Thêm tệp preset
+
+**Preset** là tệp HTML xuất từ Arma 3 Launcher chứa danh sách mod bạn đang dùng.
+
+**Cách xuất preset từ Arma 3 Launcher:**
+1. Mở Arma 3 Launcher
+2. Vào tab **Mods**
+3. Nhấn **Preset** → **Export to HTML**
+4. Lưu tệp vào máy tính
+
+**Thêm preset vào ứng dụng:**
+1. Ở mục **Tệp Preset**, nhấn **+ Thêm tệp Preset**
+2. Chọn tệp `.html` vừa xuất
+3. Tệp sẽ xuất hiện trong danh sách với ô tick
+
+### 5.2 Chọn preset để xử lý
+
+- **Tick** vào các preset bạn muốn so sánh (cần ít nhất **2 preset**)
+- Nhấn **Tất cả** để chọn tất cả, hoặc **Bỏ chọn** để bỏ hết
+- Nhãn `Đã chọn X / Y` cho biết số lượng đã chọn:
+  - Màu xanh: đã chọn đủ (≥ 2)
+  - Màu vàng: mới chọn 1
+  - Màu đỏ: chưa chọn
+
+### 5.3 Trạng thái Pipeline
+
+Cột bên phải hiển thị 5 bước của quy trình:
+
+| Bước | Mô tả | Dấu hiệu hoàn thành |
+|------|-------|-------------------|
+| Phân tích preset | Đọc danh sách mod từ tệp HTML | Có ≥ 2 preset được chọn |
+| So sánh preset | Tìm mod chung và riêng | Tệp `comparison.json` tồn tại |
+| Di chuyển nhóm mod | Chuyển thư mục mod sẵn có sang đúng nhóm mới | Tự động (không cần tải lại) |
+| Tải mod | Tải tệp mod thực sự còn thiếu từ máy chủ | Có thư mục mod trong `downloads/` |
+| Liên kết với Arma | Tạo junction tới thư mục Arma 3 | Thư mục Arma 3 Server tồn tại |
+
+Biểu tượng `✓` (xanh) = đã xong, `○` (xám) = chưa xong.
+
+### 5.4 Chạy toàn bộ quy trình
+
+1. Đảm bảo đã chọn ít nhất 2 preset
+2. Nhấn **▶ Chạy toàn bộ quy trình**
+3. Ứng dụng tự động chuyển sang tab **Nhật ký** và hiển thị tiến trình
+4. Chờ cho đến khi thấy dòng `✓ Pipeline complete.` (hoặc tiếng Việt: `✓ Hoàn thành`)
+
+> **Lưu ý:** Quá trình này có thể mất vài phút đến hàng giờ tùy số lượng và kích thước mod.
+
+---
+
+## 6. Danh sách Mod
+
+Trang này hiển thị tất cả mod được nhóm theo preset (tab).
+
+### Các tab nhóm
+
+- **shared (X)** — Mod có mặt trong **tất cả** preset đã chọn
+- **[tên preset] (X)** — Mod chỉ có trong preset đó
+
+Nhấn vào tên tab để chuyển nhóm.
+
+### Các cột thông tin
+
+| Cột | Ý nghĩa |
+|-----|---------|
+| **Tên Mod** | Tên mod theo danh sách preset |
+| **Đã tải** | `✓` = đã có trong thư mục downloads · `✗` = chưa tải |
+| **Đã liên kết** | `✓` = đã tạo junction tới Arma 3 · `✗` = chưa · `—` = chưa tải nên không liên kết được |
+| **Trạng thái máy chủ** | Xem bên dưới |
+
+### Trạng thái máy chủ
+
+Nhấn nút **☁ Kiểm tra cập nhật** để kiểm tra từng mod với máy chủ:
+
+| Trạng thái | Ý nghĩa |
+|-----------|---------|
+| `✓ Đã cập nhật` | Tệp local khớp với máy chủ |
+| `⚠ X tệp cũ` | Có X tệp cần cập nhật, nhấn **Cập nhật** ở cuối hàng |
+| `Không có trên máy chủ` | Mod này không tồn tại trên máy chủ |
+| `—` | Mod chưa được tải về |
+| `✗ Lỗi` | Không thể kiểm tra (lỗi mạng) |
+
+### Tìm kiếm mod
+
+Gõ vào ô **Tìm kiếm:** để lọc mod theo tên trong tab đang xem.
+
+---
+
+## 7. Công cụ nâng cao
+
+Trang **Công cụ** có 5 tab phụ cho các tác vụ bảo trì. Mỗi tab đều có nút chạy ở góc phải phía dưới, output hiển thị trong **Nhật ký**.
+
+| Tab | Chức năng tóm tắt |
+|-----|-------------------|
+| Check Names | Kiểm tra và sửa tên thư mục mod |
+| Update Mods | Tải lại tệp mod đã thay đổi trên máy chủ |
+| Link Mods | Tạo / xóa junction tới Arma 3 Server |
+| Sync / Report Missing | Đồng bộ và báo cáo mod còn thiếu |
+| **Clean Orphans** | Xóa thư mục mod thừa từ preset cũ |
+
+### Tab "Check Names" — Kiểm tra tên thư mục
+
+Quét thư mục mod trên máy tính và so sánh với máy chủ. Báo cáo các vấn đề:
+
+| Vấn đề | Ý nghĩa |
+|--------|---------|
+| `MISMATCH` | Tên thư mục local khác với tên trên máy chủ |
+| `NOT_ON_SERVER` | Thư mục local không tìm thấy trên máy chủ |
+| `ID_COLLISION` | Tệp `meta.cpp` chứa Steam ID sai |
+
+**Tùy chọn:**
+- `--fix`: Tự động đổi tên thư mục sai → Dùng cẩn thận, sẽ di chuyển tệp
+- `--fix-ids`: Tự động sửa Steam ID trong `meta.cpp` → Dùng cẩn thận, sẽ ghi đè tệp
+
+### Tab "Update Mods" — Cập nhật mod
+
+Tải lại các tệp mod có kích thước khác với bản trên máy chủ.
+
+- **Nhóm**: Chọn `Tất cả nhóm` hoặc một nhóm cụ thể
+- **Thư mục mod**: Nhập tên thư mục cụ thể (ví dụ `@ace`) nếu muốn cập nhật một mod
+- **--force**: Tải lại **tất cả** tệp bất kể kích thước — cẩn thận với mod nặng
+
+### Tab "Link Mods" — Quản lý liên kết
+
+Tạo hoặc xóa junction giữa thư mục `downloads/` và thư mục Arma 3.
+
+| Lệnh | Chức năng |
+|------|-----------|
+| **Status** | Hiển thị trạng thái liên kết hiện tại |
+| **Link** | Tạo junction còn thiếu |
+| **Unlink** | Xóa junction (tệp mod **KHÔNG** bị xóa) |
+
+> **Lưu ý:** Phải chọn một nhóm cụ thể trước khi chạy Unlink.
+
+### Tab "Sync Missing" — Đồng bộ mod thiếu
+
+Thử tải lại các mod bị thiếu từ lần chạy pipeline trước. Hữu ích khi máy chủ vừa bổ sung mod mới sau khi bạn đã chạy pipeline.
+
+### Tab "Report Missing" — Báo cáo mod thiếu
+
+Kiểm tra mod nào trong `comparison.json` chưa có trên máy chủ và lưu báo cáo vào `missing_report.json`. Dùng để theo dõi mod cần yêu cầu admin bổ sung.
+
+### Tab "Clean Orphans" — Dọn dẹp mod thừa
+
+Khi bạn đổi preset và chạy lại pipeline, các mod của preset cũ vẫn còn trong thư mục `downloads/` nhưng không được dùng nữa — gọi là **mod thừa** (orphan). Tab này giúp tìm và xóa chúng để giải phóng dung lượng ổ đĩa.
+
+**Cách dùng:**
+
+1. Nhấn **Quét mod thừa** — ứng dụng sẽ so sánh thư mục `downloads/` với `comparison.json` hiện tại
+2. Danh sách mod thừa hiện ra kèm tên nhóm và dung lượng
+3. Dùng **Chọn tất cả** hoặc tick thủ công từng mục
+4. Nhấn **Xóa đã chọn** — xuất hiện hộp thoại xác nhận
+5. Nhấn **Xác nhận xóa** để thực hiện; danh sách sẽ tự động quét lại sau khi xóa
+
+> **Lưu ý an toàn:** Ứng dụng chỉ xóa thư mục `@ModName` trong `downloads/`, không đụng tới thư mục Arma 3 Server. Junction (liên kết) sẽ bị xóa đúng cách mà không làm mất tệp gốc.
+
+**Yêu cầu:** Cần có `comparison.json` (chạy pipeline ít nhất một lần trước).
+
+---
+
+## 8. Nhật ký (Logs)
+
+Trang này hiển thị toàn bộ output khi chạy pipeline hoặc công cụ.
+
+- **Sao chép**: Copy toàn bộ nội dung nhật ký vào clipboard
+- **Xóa**: Xóa sạch nội dung nhật ký
+
+Output được giữ nguyên khi bạn chuyển sang trang khác và quay lại.
+
+**Ký hiệu trong log:**
+- `✓` — bước hoàn thành thành công
+- `✗` — có lỗi xảy ra
+- `SKIP` — bỏ qua (ví dụ preset không được chọn)
+
+---
+
+## 9. Cài đặt
+
+### Cấu hình máy chủ & đường dẫn
+
+Nhấn **Mở trình thiết lập** để thay đổi URL máy chủ, tài khoản, hoặc thư mục Arma 3.
+
+### Giao diện
+
+Chọn chế độ hiển thị: **Dark** (tối), **Light** (sáng), hoặc **System** (theo hệ thống).
+
+### Ngôn ngữ
+
+Xem phần [10. Đổi sang giao diện tiếng Việt](#10-đổi-sang-giao-diện-tiếng-việt).
+
+### Cấu hình hiện tại
+
+Hiển thị các đường dẫn đang dùng: URL máy chủ, thư mục Arma, thư mục downloads, thư mục presets.
+
+---
+
+## 10. Đổi sang giao diện tiếng Việt
+
+1. Nhấn **Cài đặt** ở thanh bên trái
+2. Cuộn xuống đến mục **Ngôn ngữ**
+3. Chọn **Tiếng Việt** từ danh sách thả xuống
+4. Giao diện sẽ chuyển sang tiếng Việt ngay lập tức — không cần khởi động lại
+
+Để chuyển lại tiếng Anh, chọn **English** trong cùng mục đó.
+
+> Lựa chọn ngôn ngữ được lưu vào `config.json` và sẽ được ghi nhớ cho lần khởi động tiếp theo.
+
+---
+
+## 11. Xử lý sự cố thường gặp
+
+### Không kết nối được máy chủ
+
+**Triệu chứng:** Wizard hiển thị `✗ HTTP 401` hoặc `✗ [lỗi kết nối]`
+
+**Kiểm tra:**
+- URL có bắt đầu bằng `https://` không?
+- URL có dấu `/` ở cuối không? (ví dụ `https://mods.example.com/`)
+- Tên đăng nhập và mật khẩu có đúng không? (kiểm tra phân biệt hoa thường)
+- Máy tính có kết nối internet không?
+- Máy chủ có đang hoạt động không? (hỏi admin)
+
+### Pipeline chạy xong nhưng không tải được mod
+
+**Triệu chứng:** Log hiển thị `missing from server` hoặc `NOT_ON_SERVER`
+
+**Giải thích:** Mod tồn tại trong preset nhưng chưa có trên máy chủ.
+
+**Xử lý:**
+- Vào **Công cụ → Report Missing** để tạo báo cáo
+- Gửi báo cáo cho admin để bổ sung mod
+- Sau khi mod được thêm, vào **Công cụ → Sync Missing** để tải về
+
+### Mod tải về rồi nhưng không liên kết được
+
+**Triệu chứng:** Cột "Đã tải" là `✓` nhưng "Đã liên kết" là `✗`
+
+**Xử lý:**
+- Vào **Công cụ → Link Mods**, chọn lệnh **Link**, chọn nhóm tương ứng, nhấn **Tạo liên kết**
+- Nếu vẫn lỗi, kiểm tra quyền ghi vào thư mục Arma 3 (có thể cần chạy ứng dụng với quyền Administrator)
+
+### Tên thư mục mod bị sai
+
+**Triệu chứng:** Arma 3 Server không nhận ra mod dù đã tạo junction
+
+**Xử lý:**
+- Vào **Công cụ → Check Names**, nhấn **Chạy kiểm tra tên**
+- Xem log để tìm dòng `MISMATCH`
+- Nếu muốn tự động sửa, tick vào **Tự động sửa tên thư mục** rồi chạy lại
+
+### Ứng dụng không khởi động / lỗi Python
+
+**Triệu chứng:** Màn hình đen nháy tắt ngay
+
+**Xử lý:**
+- Mở Command Prompt, chạy `python gui.py` để xem thông báo lỗi
+- Đảm bảo đã cài đủ thư viện: `pip install -r requirements.txt`
+- Kiểm tra phiên bản Python: `python --version` (cần ≥ 3.9)
+
+---
+
+## 12. Bảng thuật ngữ
+
+| Thuật ngữ | Giải thích |
+|-----------|------------|
+| **Preset** | Tệp HTML xuất từ Arma 3 Launcher chứa danh sách mod |
+| **Pipeline** | Chuỗi 5 bước tự động: phân tích → so sánh → di chuyển nhóm → tải → liên kết |
+| **Junction / Symlink** | Liên kết thư mục ảo — Arma 3 thấy mod trong thư mục của mình nhưng tệp thực sự nằm ở `downloads/` |
+| **Shared mods** | Mod xuất hiện trong tất cả preset đã chọn |
+| **Unique mods** | Mod chỉ có trong một preset cụ thể |
+| **Caddy server** | Phần mềm máy chủ lưu trữ tệp mod (HTTP file server) |
+| **meta.cpp** | Tệp metadata của mỗi mod, chứa `publishedid` (Steam Workshop ID) |
+| **Steam ID / publishedid** | Mã định danh mod trên Steam Workshop |
+| **comparison.json** | Tệp kết quả so sánh preset, lưu danh sách mod theo nhóm |
+| **missing_report.json** | Báo cáo mod có trong preset nhưng chưa có trên máy chủ |
+| **downloads/** | Thư mục chứa tệp mod đã tải về |
+| **Di chuyển nhóm mod** | Bước tự động chuyển thư mục mod từ nhóm cũ sang nhóm mới theo `comparison.json` — tránh tải lại khi đổi phiên bản preset |
+| **Mod thừa (Orphan)** | Thư mục mod còn trong `downloads/` nhưng không còn trong preset nào đang dùng |
+| **config.json** | Tệp cấu hình lưu thông tin máy chủ và đường dẫn |
+
+---
+
+*Phiên bản tài liệu: 2026-04 (cập nhật: thêm bước Di chuyển nhóm mod, pipeline 5 bước). Nếu có vấn đề, liên hệ người quản trị máy chủ.*

gui/_io.py

@@ -2,6 +2,14 @@ from __future__ import annotations
 
 import io
 import queue
+import re
+
+# Strip ANSI escape sequences and normalise carriage returns so tqdm output
+# is readable in the log textbox (which has no terminal emulation).
+_ANSI_RE = re.compile(
+    r"\x1b\[[0-9;]*[A-Za-z]"           # CSI sequences  e.g. \x1b[32m
+    r"|\x1b\][^\x07\x1b]*(?:\x07|\x1b\\)"  # OSC sequences, BEL or ST terminator
+)
 
 
 class _QueueWriter(io.TextIOBase):
@@ -12,7 +20,11 @@ class _QueueWriter(io.TextIOBase):
 
     def write(self, text: str) -> int:  # type: ignore[override]
         if text:
-            self._q.put(text)
+            cleaned = _ANSI_RE.sub("", text)
+            cleaned = cleaned.replace("\r\n", "\n")  # Windows CRLF → LF
+            cleaned = cleaned.replace("\r", "\n")    # bare CR → newline
+            if cleaned:
+                self._q.put(cleaned)
         return len(text)
 
     def flush(self) -> None:

gui/app.py

@@ -1,12 +1,17 @@
 from __future__ import annotations
 
 import json
+import os
 import queue
 import subprocess
 import sys
 import threading
 from pathlib import Path
-from typing import Optional
+from typing import TYPE_CHECKING, Optional
+
+if TYPE_CHECKING:
+    from arma_modlist_tools.config import Config
+    from gui.views.dashboard import DashboardView
 
 import customtkinter as ctk
 from tkinter import messagebox
@@ -15,6 +20,7 @@ from gui._constants import (
     SIDEBAR_W, APP_TITLE, PROJECT_ROOT, SELECTION_FILE,
 )
 from gui._io import _QueueWriter
+from gui.locales import t
 from gui.wizard import SetupWizard
 from gui.views.base import BaseView
 
@@ -26,7 +32,7 @@ from gui.views.base import BaseView
 _VIEW_NAMES = ("Dashboard", "Mods", "Tools", "Logs", "Settings")
 
 
-def _get_view_class(name: str):
+def _get_view_class(name: str) -> type[BaseView]:
     from gui.views import DashboardView, ModsView, ToolsView, LogsView, SettingsView
     return {
         "Dashboard": DashboardView,
@@ -62,6 +68,7 @@ class ArmaModManagerApp(ctk.CTk):
         else:
             self._load_config()
 
+        self._apply_startup_language()
         self._build_layout()
         self._poll_log()
 
@@ -70,7 +77,7 @@ class ArmaModManagerApp(ctk.CTk):
     # =========================================================================
 
     @property
-    def cfg(self):
+    def cfg(self) -> Optional["Config"]:
         """Loaded Config object, or None if config.json is missing/invalid."""
         return self._cfg
 
@@ -106,38 +113,59 @@ class ArmaModManagerApp(ctk.CTk):
         """Thread-safe: enqueue text for the Logs panel."""
         self._log_q.put(text)
 
+    def switch_language(self, lang: str) -> None:
+        """Switch the UI language and refresh all cached views."""
+        from gui import locales
+        locales.set_language(lang)
+        self._save_language_pref(lang)
+        self._rebuild_nav_labels()
+        for view in self._view_cache.values():
+            view.refresh()
+        if self._active_name:
+            self.navigate_to(self._active_name)
+
     def run_pipeline(self, selected_names: set[str]) -> None:
         """Start the background pipeline for the given preset filenames."""
         if self._pipeline_running:
             return
         if len(selected_names) < 2:
             messagebox.showwarning(
-                "Not enough presets selected",
-                "Please select at least 2 preset files to compare.\n\n"
-                "Use the checkboxes on the Dashboard to choose which presets to use.",
+                t("app.dlg_presets_title"),
+                t("app.dlg_presets_body"),
             )
             return
 
         cfg = self._cfg
         if not cfg:
-            messagebox.showwarning("Setup required", "Please complete Setup first.")
+            messagebox.showwarning(t("app.dlg_setup_title"), t("app.dlg_setup_body"))
             return
 
         self._pipeline_running = True
         self._get_dashboard().set_pipeline_ui(running=True)
         self.navigate_to("Logs")
+        # Post an immediate banner so the log is never blank after clicking Start.
+        _sep = "=" * 50
+        self.post_log(f"\n{_sep}\n  {t('pipeline.starting')}\n{_sep}\n\n")
 
         def worker() -> None:
             # run.py calls fix_console_encoding() at import time, which needs
             # the real sys.stdout.buffer. Import it before we redirect stdout.
-            from run import step_fetch, step_link
+            try:
+                from run import step_migrate, step_fetch, step_link
+            except Exception as _import_err:
+                self.after(0, lambda: self.post_log(
+                    f"\n✗  Failed to load pipeline: {_import_err}\n"
+                ))
+                self.after(0, self._pipeline_done)
+                return
+
             self._redirect_output()
             try:
                 from arma_modlist_tools.parser  import parse_modlist_html
                 from arma_modlist_tools.compare import compare_presets
 
                 # Step 1 — Parse selected presets
-                _hdr("Step 1 / 4", "Parse presets")
+                _hdr("Step 1 / 5", t("pipeline.step1_name"))
                 cfg.modlist_json.mkdir(exist_ok=True)
                 presets = []
                 for fp in sorted(cfg.modlist_html.glob("*.html")):
@@ -154,7 +182,7 @@ class ArmaModManagerApp(ctk.CTk):
                     presets.append(preset)
 
                 # Step 2 — Compare
-                _hdr("Step 2 / 4", "Compare presets")
+                _hdr("Step 2 / 5", t("pipeline.step2_name"))
                 result = compare_presets(*presets)
                 cfg.comparison.write_text(
                     json.dumps(result, indent=2, ensure_ascii=False),
@@ -165,12 +193,16 @@ class ArmaModManagerApp(ctk.CTk):
                 print(f"  Shared: {result['shared']['mod_count']}  |  "
                       f"Unique: {total_unique}")
 
-                # Step 3 — Fetch
-                _hdr("Step 3 / 4", "Download mods")
+                # Step 3 — Migrate
+                _hdr("Step 3 / 5", t("pipeline.step3_name"))
+                step_migrate(cfg)
+
+                # Step 4 — Fetch
+                _hdr("Step 4 / 5", t("pipeline.step4_name"))
                 step_fetch(cfg)
 
-                # Step 4 — Link
-                _hdr("Step 4 / 4", "Link mods")
+                # Step 5 — Link
+                _hdr("Step 5 / 5", t("pipeline.step5_name"))
                 groups = (
                     sorted(p.name for p in cfg.downloads.iterdir() if p.is_dir())
                     if cfg.downloads.is_dir() else []
@@ -197,20 +229,30 @@ class ArmaModManagerApp(ctk.CTk):
         def worker() -> None:
             self.post_log(f"\n{'─'*50}\n  {' '.join(script_args)}\n{'─'*50}\n")
             try:
-                result = subprocess.run(
-                    [sys.executable, str(PROJECT_ROOT / script)] + extra,
-                    capture_output=True, text=True, cwd=str(PROJECT_ROOT),
+                env = os.environ.copy()
+                env["PYTHONUNBUFFERED"] = "1"
+                env["PYTHONUTF8"] = "1"
+                proc = subprocess.Popen(
+                    [sys.executable, "-u", str(PROJECT_ROOT / script)] + extra,
+                    stdout=subprocess.PIPE,
+                    stderr=subprocess.STDOUT,
+                    text=True,
+                    encoding="utf-8",
+                    errors="replace",
+                    cwd=str(PROJECT_ROOT),
+                    env=env,
                 )
-                if result.stdout:
-                    self.post_log(result.stdout)
-                if result.stderr:
-                    self.post_log(result.stderr)
-                ok = result.returncode == 0
-                self.post_log(
-                    f"\n{'✓  Done' if ok else f'✗  Exited with code {result.returncode}'}.\n"
+                for line in iter(proc.stdout.readline, ""):
+                    self.post_log(line)
+                proc.wait()
+                ok = proc.returncode == 0
+                done_msg = (
+                    t("app.tool_done") if ok
+                    else t("app.tool_exit_code", code=proc.returncode)
                 )
+                self.post_log(f"\n{done_msg}.\n")
             except Exception as e:
-                self.post_log(f"\n✗  Failed to start {script}: {e}\n")
+                self.post_log(f"\n{t('app.tool_failed', script=script, e=e)}\n")
 
         threading.Thread(target=worker, daemon=True).start()
 
@@ -235,6 +277,40 @@ class ArmaModManagerApp(ctk.CTk):
     def open_wizard(self) -> None:
         SetupWizard(self, on_complete=self._after_wizard)
 
+    # =========================================================================
+    # Private — language
+    # =========================================================================
+
+    @staticmethod
+    def _read_raw_config() -> dict:
+        """Return config.json as a raw dict, or {} on missing / parse error."""
+        try:
+            return json.loads((PROJECT_ROOT / "config.json").read_text(encoding="utf-8"))
+        except Exception:
+            return {}
+
+    def _apply_startup_language(self) -> None:
+        """Read language preference from config.json and activate it."""
+        from gui import locales
+        lang = self._read_raw_config().get("ui", {}).get("language", "en")
+        locales.set_language(lang)
+
+    def _save_language_pref(self, lang: str) -> None:
+        """Persist language preference into the 'ui' key of config.json."""
+        try:
+            raw = self._read_raw_config()
+            raw.setdefault("ui", {})["language"] = lang
+            (PROJECT_ROOT / "config.json").write_text(
+                json.dumps(raw, indent=2), encoding="utf-8"
+            )
+        except Exception:
+            pass  # non-fatal — language preference simply resets next run
+
+    def _rebuild_nav_labels(self) -> None:
+        """Retranslate the sidebar navigation button labels."""
+        for name, btn in self._nav_btns.items():
+            btn.configure(text=t(f"nav.{name.lower()}"))
+
     # =========================================================================
     # Private — layout
     # =========================================================================
@@ -258,7 +334,7 @@ class ArmaModManagerApp(ctk.CTk):
         self._nav_btns: dict[str, ctk.CTkButton] = {}
         for i, name in enumerate(_VIEW_NAMES, start=1):
             b = ctk.CTkButton(
-                sb, text=name, width=SIDEBAR_W - 24,
+                sb, text=t(f"nav.{name.lower()}"), width=SIDEBAR_W - 24,
                 anchor="w", command=lambda n=name: self.navigate_to(n),
                 fg_color="transparent",
                 hover_color=("gray80", "gray30"),
@@ -310,15 +386,16 @@ class ArmaModManagerApp(ctk.CTk):
     # =========================================================================
 
     def _poll_log(self) -> None:
+        parts: list[str] = []
         try:
-            from gui.views.logs import LogsView
-            logs_view = self._view_cache.get("Logs")
             while True:
-                text = self._log_q.get_nowait()
-                if isinstance(logs_view, LogsView):
-                    logs_view.append(text)
+                parts.append(self._log_q.get_nowait())
         except queue.Empty:
             pass
+        if parts:
+            logs_view = self._view_cache.get("Logs")
+            if logs_view is not None and hasattr(logs_view, "append"):
+                logs_view.append("".join(parts))  # type: ignore[attr-defined]
         self.after(80, self._poll_log)
 
     def _redirect_output(self) -> None:
@@ -341,7 +418,7 @@ class ArmaModManagerApp(ctk.CTk):
         for view in self._view_cache.values():
             view.refresh()
 
-    def _get_dashboard(self):
+    def _get_dashboard(self) -> "DashboardView":
         from gui.views.dashboard import DashboardView
         view = self._view_cache.get("Dashboard")
         if not isinstance(view, DashboardView):

gui/locales.py

@@ -0,0 +1,534 @@
+from __future__ import annotations
+
+# ---------------------------------------------------------------------------
+# Localization module — English + Vietnamese
+#
+# Usage:
+#   from gui.locales import t
+#   label_text = t("dashboard.title")
+#   label_text = t("dashboard.sel_count", n_sel=2, n_total=5)
+#
+# Tab names in ToolsView are NOT translated — they double as CTkTabview
+# lookup keys and cannot be renamed after creation.
+# Segmented-button values in ToolsView ("Status", "Link", "Unlink") are also
+# kept in English because they drive internal logic in _lm_on_change().
+# ---------------------------------------------------------------------------
+
+_LANG: str = "en"
+
+_EN: dict[str, str] = {
+    # ── App / sidebar ────────────────────────────────────────────────────────
+    "app.title":                     "Arma Mod Manager",
+    "nav.dashboard":                 "Dashboard",
+    "nav.mods":                      "Mods",
+    "nav.tools":                     "Tools",
+    "nav.logs":                      "Logs",
+    "nav.settings":                  "Settings",
+
+    # ── Pipeline step headers (printed to log) ───────────────────────────────
+    "pipeline.starting":             "Pipeline started",
+    "pipeline.step1_name":           "Parse presets",
+    "pipeline.step2_name":           "Compare presets",
+    "pipeline.step3_name":           "Migrate mod groups",
+    "pipeline.step4_name":           "Download mods",
+    "pipeline.step5_name":           "Link mods",
+
+    # ── app.py dialogs ────────────────────────────────────────────────────────
+    "app.dlg_presets_title":         "Not enough presets selected",
+    "app.dlg_presets_body":          (
+        "Please select at least 2 preset files to compare.\n\n"
+        "Use the checkboxes on the Dashboard to choose which presets to use."
+    ),
+    "app.dlg_setup_title":           "Setup required",
+    "app.dlg_setup_body":            "Please complete Setup first.",
+
+    # ── run_tool status lines (go to log) ────────────────────────────────────
+    "app.tool_done":                 "✓  Done",
+    "app.tool_exit_code":            "✗  Exited with code {code}",
+    "app.tool_failed":               "✗  Failed to start {script}: {e}",
+
+    # ── Dashboard ────────────────────────────────────────────────────────────
+    "dashboard.title":               "Dashboard",
+    "dashboard.refresh_btn":         "⟳  Refresh",
+    "dashboard.preset_card_title":   "Preset Files",
+    "dashboard.preset_card_desc":    "HTML exports from Arma 3 Launcher → Mods → Export to HTML",
+    "dashboard.sel_count":           "{n_sel} of {n_total} selected",
+    "dashboard.btn_none":            "None",
+    "dashboard.btn_all":             "All",
+    "dashboard.btn_add":             "+ Add Preset Files",
+    "dashboard.no_config":           "No config found. Complete Setup first.",
+    "dashboard.folder_missing":      "Folder missing:\n{path}",
+    "dashboard.no_presets":          "No preset files yet.\nUse the button below to add them.",
+    "dashboard.file_dialog_title":   "Select Arma 3 Launcher preset files",
+    "dashboard.dlg_setup_title":     "Setup required",
+    "dashboard.dlg_setup_body":      "Please complete Setup before adding presets.",
+    "dashboard.pipeline_title":      "Pipeline Status",
+    "dashboard.step_parse":          "Parse presets",
+    "dashboard.step_compare":        "Compare presets",
+    "dashboard.step_download":       "Download mods",
+    "dashboard.step_link":           "Link to Arma",
+    "dashboard.stats":               "{total} mods · {shared} shared",
+    "dashboard.stats_missing":       "\n{missing} missing from server",
+    "dashboard.run_btn":             "▶   Run Full Pipeline",
+    "dashboard.running":             "Running…",
+
+    # ── Mods ─────────────────────────────────────────────────────────────────
+    "mods.title":                    "Mods",
+    "mods.refresh_btn":              "⟳  Refresh",
+    "mods.check_btn":                "☁  Check Updates",
+    "mods.check_btn_checking":       "Checking…",
+    "mods.search_label":             "Search:",
+    "mods.search_placeholder":       "Filter mods in active tab…",
+    "mods.no_config":                "No config found. Complete Setup first.",
+    "mods.no_data":                  (
+        "No mod data yet.\n"
+        "Go to Dashboard, select your presets, then click Run Full Pipeline."
+    ),
+    "mods.read_error":               "Error reading comparison.json: {e}",
+    "mods.col_name":                 "Mod Name",
+    "mods.col_downloaded":           "Downloaded",
+    "mods.col_linked":               "Linked",
+    "mods.col_server":               "Server Status",
+    "mods.status_ok":                "✓ Up to date",
+    "mods.status_stale":             "⚠ {n} outdated",
+    "mods.status_not_downloaded":    "—",
+    "mods.status_not_on_server":     "Not on server",
+    "mods.status_error":             "✗ Error",
+    "mods.status_checking":          "Checking…",
+    "mods.update_btn":               "Update",
+
+    # ── Logs ─────────────────────────────────────────────────────────────────
+    "logs.title":                    "Logs",
+    "logs.copy_btn":                 "Copy",
+    "logs.clear_btn":                "Clear",
+
+    # ── Settings ─────────────────────────────────────────────────────────────
+    "settings.title":                "Settings",
+    "settings.server_card_title":    "Server & Path Configuration",
+    "settings.server_card_desc":     (
+        "Re-run the setup wizard to change your server URL, "
+        "credentials, or Arma folder."
+    ),
+    "settings.wizard_btn":           "Open Setup Wizard",
+    "settings.appearance_title":     "Appearance",
+    "settings.language_title":       "Language",
+    "settings.config_title":         "Current Configuration",
+
+    # ── Wizard ───────────────────────────────────────────────────────────────
+    "wizard.title":                  "Setup — Arma Mod Manager",
+    "wizard.step1_title":            "Step 1 of 3 — Server Connection",
+    "wizard.step1_desc":             "Enter the details for your Caddy mod server.",
+    "wizard.label_url":              "Server URL",
+    "wizard.label_user":             "Username",
+    "wizard.label_pw":               "Password",
+    "wizard.btn_next":               "Next →",
+    "wizard.btn_test":               "Test Connection",
+    "wizard.testing":                "Testing…",
+    "wizard.connected":              "✓ Connected",
+    "wizard.http_error":             "✗ HTTP {code}",
+    "wizard.conn_error":             "✗ {e}",
+    "wizard.step2_title":            "Step 2 of 3 — Arma 3 Server Folder",
+    "wizard.step2_desc":             (
+        "Point to your Arma 3 Server installation. "
+        "Links (junctions) will be created here."
+    ),
+    "wizard.label_arma":             "Arma 3 Server folder",
+    "wizard.btn_browse":             "Browse",
+    "wizard.step2_hint":             (
+        "All other folders (downloads, presets) will be created "
+        "automatically next to this tool."
+    ),
+    "wizard.btn_back":               "← Back",
+    "wizard.step3_title":            "Step 3 of 3 — Review & Save",
+    "wizard.step3_desc":             "Check your settings, then click Save.",
+    "wizard.not_set":                "(not set)",
+    "wizard.btn_save":               "Save & Open",
+    "wizard.browse_title":           "Select Arma 3 Server folder",
+
+    # ── Tools — shared ────────────────────────────────────────────────────────
+    "tools.title":                   "Tools",
+    "tools.label_group":             "Group:",
+    "tools.label_options":           "Options:",
+    "tools.label_command":           "Command:",
+    "tools.all_groups":              "All groups",
+    "tools.no_groups":               "(no groups found)",
+
+    # ── Tools — Check Names ──────────────────────────────────────────────────
+    "tools.cn_desc":                 (
+        "Scan mod folders and compare against the server. "
+        "Reports naming mismatches (MISMATCH), unrecognised folders "
+        "(NOT_ON_SERVER), and wrong Steam IDs in meta.cpp (ID_COLLISION)."
+    ),
+    "tools.cn_fix_chk":              "Auto-fix folder name mismatches  (--fix)",
+    "tools.cn_fix_ids_chk":          "Auto-fix wrong Steam IDs in meta.cpp  (--fix-ids)",
+    "tools.cn_warn":                 (
+        "⚠  --fix renames folders and updates junctions.  "
+        "--fix-ids rewrites meta.cpp files."
+    ),
+    "tools.cn_btn":                  "Run Check Names",
+
+    # ── Tools — Update Mods ──────────────────────────────────────────────────
+    "tools.um_desc":                 (
+        "Re-download mod files whose size on the server differs from "
+        "your local copy.  Use --force to re-download everything "
+        "regardless of size."
+    ),
+    "tools.um_mod_label":            "Mod folder:",
+    "tools.um_mod_placeholder":      "Optional — e.g. @ace",
+    "tools.um_mod_hint":             "(only when a specific group is selected)",
+    "tools.um_force_chk":            "Force re-download all files  (--force)",
+    "tools.um_warn":                 (
+        "⚠  --force re-downloads every file regardless of size. "
+        "This may transfer a large amount of data."
+    ),
+    "tools.um_btn":                  "Run Update",
+
+    # ── Tools — Link Mods ────────────────────────────────────────────────────
+    "tools.lm_desc":                 (
+        "Manage junction/symlink links between your downloads folder "
+        "and the Arma 3 directory.\n"
+        "Status — show what's linked.  "
+        "Link — create missing junctions.  "
+        "Unlink — remove junctions (mod files are NOT deleted)."
+    ),
+    "tools.lm_warn":                 (
+        "⚠  Unlink removes junction links from the Arma 3 directory. "
+        "Mod files in downloads/ are NOT deleted."
+    ),
+    "tools.lm_show_status":          "Show Status",
+    "tools.lm_create_links":         "Create Links",
+    "tools.lm_remove_links":         "Remove Links",
+    "tools.lm_no_group_title":       "No group selected",
+    "tools.lm_no_group_body":        "Please select a group from the dropdown.",
+    "tools.lm_confirm_title":        "Confirm Unlink",
+    "tools.lm_confirm_body":         (
+        "Remove junction links for group '{group}'?\n\n"
+        "This removes links from the Arma 3 directory but does NOT delete "
+        "mod files in downloads/."
+    ),
+
+    # ── Tools — Sync Missing ─────────────────────────────────────────────────
+    "tools.sm_desc":                 (
+        "Retry downloading mods that were missing from the server "
+        "when you last ran the pipeline. "
+        "Checks the server again and downloads any that have since appeared."
+    ),
+    "tools.sm_btn":                  "Run Sync Missing",
+    "tools.sm_count":                "{count} mod(s) currently listed as missing.",
+    "tools.sm_no_report":            "No missing_report.json found — run the pipeline first.",
+
+    # ── Tools — Report Missing ───────────────────────────────────────────────
+    "tools.rm_desc":                 (
+        "Check which mods from comparison.json are absent from the "
+        "file server. Saves missing_report.json so you can track what "
+        "still needs to be added to the server."
+    ),
+    "tools.rm_btn":                  "Generate Report",
+    "tools.rm_last":                 "Last generated: {ts}",
+    "tools.rm_none":                 "No report yet.",
+
+    # ── Tools — Clean Orphans ────────────────────────────────────────────────
+    "tools.oc_desc":                 (
+        "Scan the downloads folder for mod folders that are no longer "
+        "referenced in comparison.json.  These orphans accumulate when you "
+        "remove mods from your presets and re-run the pipeline.  "
+        "Select the ones you want to remove to free up disk space."
+    ),
+    "tools.oc_warn":                 (
+        "⚠  Deleting orphans permanently removes mod files from disk. "
+        "This cannot be undone."
+    ),
+    "tools.oc_scan_btn":             "Scan for Orphans",
+    "tools.oc_scanning":             "Scanning…",
+    "tools.oc_no_config":            "No config found. Complete Setup first.",
+    "tools.oc_no_comparison":        "No comparison.json found — run the pipeline first.",
+    "tools.oc_none_found":           "No orphans found.  Your downloads folder is clean.",
+    "tools.oc_found":                "{count} orphan(s) found — {size} total",
+    "tools.oc_sel_all":              "Select All",
+    "tools.oc_sel_none":             "Deselect All",
+    "tools.oc_delete_btn":           "Delete Selected",
+    "tools.oc_confirm_title":        "Confirm Delete",
+    "tools.oc_confirm_body":         (
+        "Permanently delete {count} orphan folder(s) ({size})?\n\n"
+        "This cannot be undone."
+    ),
+    "tools.oc_done":                 "Deleted {count} folder(s), freed {size}.",
+    "tools.oc_error":                "Error deleting {path}: {e}",
+    "tools.oc_error_title":          "Delete errors",
+    "tools.oc_scan_error":           "Scan error: {e}",
+}
+
+_VI: dict[str, str] = {
+    # ── App / sidebar ────────────────────────────────────────────────────────
+    "app.title":                     "Arma Mod Manager",
+    "nav.dashboard":                 "Tổng quan",
+    "nav.mods":                      "Danh sách Mod",
+    "nav.tools":                     "Công cụ",
+    "nav.logs":                      "Nhật ký",
+    "nav.settings":                  "Cài đặt",
+
+    # ── Pipeline step headers ────────────────────────────────────────────────
+    "pipeline.starting":             "Pipeline đã bắt đầu",
+    "pipeline.step1_name":           "Phân tích preset",
+    "pipeline.step2_name":           "So sánh preset",
+    "pipeline.step3_name":           "Di chuyển nhóm mod",
+    "pipeline.step4_name":           "Tải mod",
+    "pipeline.step5_name":           "Liên kết mod",
+
+    # ── app.py dialogs ────────────────────────────────────────────────────────
+    "app.dlg_presets_title":         "Chưa chọn đủ preset",
+    "app.dlg_presets_body":          (
+        "Vui lòng chọn ít nhất 2 tệp preset để so sánh.\n\n"
+        "Sử dụng các ô tick ở Tổng quan để chọn preset."
+    ),
+    "app.dlg_setup_title":           "Cần thiết lập",
+    "app.dlg_setup_body":            "Vui lòng hoàn thành thiết lập trước.",
+
+    # ── run_tool status lines ────────────────────────────────────────────────
+    "app.tool_done":                 "✓  Hoàn thành",
+    "app.tool_exit_code":            "✗  Thoát với mã lỗi {code}",
+    "app.tool_failed":               "✗  Không thể khởi động {script}: {e}",
+
+    # ── Dashboard ────────────────────────────────────────────────────────────
+    "dashboard.title":               "Tổng quan",
+    "dashboard.refresh_btn":         "⟳  Làm mới",
+    "dashboard.preset_card_title":   "Tệp Preset",
+    "dashboard.preset_card_desc":    "Xuất từ Arma 3 Launcher → Mods → Export to HTML",
+    "dashboard.sel_count":           "Đã chọn {n_sel} / {n_total}",
+    "dashboard.btn_none":            "Bỏ chọn",
+    "dashboard.btn_all":             "Tất cả",
+    "dashboard.btn_add":             "+ Thêm tệp Preset",
+    "dashboard.no_config":           "Chưa tìm thấy cấu hình. Vui lòng hoàn thành thiết lập.",
+    "dashboard.folder_missing":      "Thư mục không tồn tại:\n{path}",
+    "dashboard.no_presets":          "Chưa có tệp preset.\nDùng nút bên dưới để thêm.",
+    "dashboard.file_dialog_title":   "Chọn tệp preset Arma 3 Launcher",
+    "dashboard.dlg_setup_title":     "Cần thiết lập",
+    "dashboard.dlg_setup_body":      "Vui lòng hoàn thành thiết lập trước khi thêm preset.",
+    "dashboard.pipeline_title":      "Trạng thái Pipeline",
+    "dashboard.step_parse":          "Phân tích preset",
+    "dashboard.step_compare":        "So sánh preset",
+    "dashboard.step_download":       "Tải mod",
+    "dashboard.step_link":           "Liên kết với Arma",
+    "dashboard.stats":               "{total} mod · {shared} dùng chung",
+    "dashboard.stats_missing":       "\n{missing} mod thiếu trên máy chủ",
+    "dashboard.run_btn":             "▶   Chạy toàn bộ quy trình",
+    "dashboard.running":             "Đang chạy…",
+
+    # ── Mods ─────────────────────────────────────────────────────────────────
+    "mods.title":                    "Danh sách Mod",
+    "mods.refresh_btn":              "⟳  Làm mới",
+    "mods.check_btn":                "☁  Kiểm tra cập nhật",
+    "mods.check_btn_checking":       "Đang kiểm tra…",
+    "mods.search_label":             "Tìm kiếm:",
+    "mods.search_placeholder":       "Lọc mod trong tab hiện tại…",
+    "mods.no_config":                "Chưa tìm thấy cấu hình. Vui lòng hoàn thành thiết lập.",
+    "mods.no_data":                  (
+        "Chưa có dữ liệu mod.\n"
+        "Vào Tổng quan, chọn preset rồi nhấn Chạy toàn bộ quy trình."
+    ),
+    "mods.read_error":               "Lỗi đọc comparison.json: {e}",
+    "mods.col_name":                 "Tên Mod",
+    "mods.col_downloaded":           "Đã tải",
+    "mods.col_linked":               "Đã liên kết",
+    "mods.col_server":               "Trạng thái máy chủ",
+    "mods.status_ok":                "✓ Đã cập nhật",
+    "mods.status_stale":             "⚠ {n} tệp cũ",
+    "mods.status_not_downloaded":    "—",
+    "mods.status_not_on_server":     "Không có trên máy chủ",
+    "mods.status_error":             "✗ Lỗi",
+    "mods.status_checking":          "Đang kiểm tra…",
+    "mods.update_btn":               "Cập nhật",
+
+    # ── Logs ─────────────────────────────────────────────────────────────────
+    "logs.title":                    "Nhật ký",
+    "logs.copy_btn":                 "Sao chép",
+    "logs.clear_btn":                "Xóa",
+
+    # ── Settings ─────────────────────────────────────────────────────────────
+    "settings.title":                "Cài đặt",
+    "settings.server_card_title":    "Cấu hình máy chủ & đường dẫn",
+    "settings.server_card_desc":     (
+        "Mở lại trình hướng dẫn thiết lập để thay đổi URL máy chủ, "
+        "thông tin đăng nhập hoặc thư mục Arma."
+    ),
+    "settings.wizard_btn":           "Mở trình thiết lập",
+    "settings.appearance_title":     "Giao diện",
+    "settings.language_title":       "Ngôn ngữ",
+    "settings.config_title":         "Cấu hình hiện tại",
+
+    # ── Wizard ───────────────────────────────────────────────────────────────
+    "wizard.title":                  "Thiết lập — Arma Mod Manager",
+    "wizard.step1_title":            "Bước 1 / 3 — Kết nối máy chủ",
+    "wizard.step1_desc":             "Nhập thông tin máy chủ Caddy của bạn.",
+    "wizard.label_url":              "URL máy chủ",
+    "wizard.label_user":             "Tên đăng nhập",
+    "wizard.label_pw":               "Mật khẩu",
+    "wizard.btn_next":               "Tiếp theo →",
+    "wizard.btn_test":               "Kiểm tra kết nối",
+    "wizard.testing":                "Đang kiểm tra…",
+    "wizard.connected":              "✓ Đã kết nối",
+    "wizard.http_error":             "✗ HTTP {code}",
+    "wizard.conn_error":             "✗ {e}",
+    "wizard.step2_title":            "Bước 2 / 3 — Thư mục Arma 3 Server",
+    "wizard.step2_desc":             (
+        "Trỏ tới thư mục cài đặt Arma 3 Server của bạn. "
+        "Các liên kết (junction) sẽ được tạo tại đây."
+    ),
+    "wizard.label_arma":             "Thư mục Arma 3 Server",
+    "wizard.btn_browse":             "Duyệt",
+    "wizard.step2_hint":             (
+        "Các thư mục khác (downloads, presets) sẽ được tạo tự động "
+        "bên cạnh công cụ này."
+    ),
+    "wizard.btn_back":               "← Quay lại",
+    "wizard.step3_title":            "Bước 3 / 3 — Xem lại & Lưu",
+    "wizard.step3_desc":             "Kiểm tra cài đặt rồi nhấn Lưu.",
+    "wizard.not_set":                "(chưa đặt)",
+    "wizard.btn_save":               "Lưu & Mở",
+    "wizard.browse_title":           "Chọn thư mục Arma 3 Server",
+
+    # ── Tools — shared ────────────────────────────────────────────────────────
+    "tools.title":                   "Công cụ",
+    "tools.label_group":             "Nhóm:",
+    "tools.label_options":           "Tùy chọn:",
+    "tools.label_command":           "Lệnh:",
+    "tools.all_groups":              "Tất cả nhóm",
+    "tools.no_groups":               "(không tìm thấy nhóm)",
+
+    # ── Tools — Check Names ──────────────────────────────────────────────────
+    "tools.cn_desc":                 (
+        "Quét thư mục mod và so sánh với máy chủ. "
+        "Báo cáo tên không khớp (MISMATCH), thư mục không nhận ra "
+        "(NOT_ON_SERVER) và Steam ID sai trong meta.cpp (ID_COLLISION)."
+    ),
+    "tools.cn_fix_chk":              "Tự động sửa tên thư mục không khớp  (--fix)",
+    "tools.cn_fix_ids_chk":          "Tự động sửa Steam ID sai trong meta.cpp  (--fix-ids)",
+    "tools.cn_warn":                 (
+        "⚠  --fix đổi tên thư mục và cập nhật junction.  "
+        "--fix-ids ghi đè tệp meta.cpp."
+    ),
+    "tools.cn_btn":                  "Chạy kiểm tra tên",
+
+    # ── Tools — Update Mods ──────────────────────────────────────────────────
+    "tools.um_desc":                 (
+        "Tải lại tệp mod có kích thước khác với bản trên máy chủ.  "
+        "Dùng --force để tải lại tất cả bất kể kích thước."
+    ),
+    "tools.um_mod_label":            "Thư mục mod:",
+    "tools.um_mod_placeholder":      "Không bắt buộc — ví dụ @ace",
+    "tools.um_mod_hint":             "(chỉ dùng khi chọn một nhóm cụ thể)",
+    "tools.um_force_chk":            "Buộc tải lại tất cả tệp  (--force)",
+    "tools.um_warn":                 (
+        "⚠  --force tải lại mọi tệp bất kể kích thước. "
+        "Điều này có thể truyền một lượng dữ liệu lớn."
+    ),
+    "tools.um_btn":                  "Chạy cập nhật",
+
+    # ── Tools — Link Mods ────────────────────────────────────────────────────
+    "tools.lm_desc":                 (
+        "Quản lý liên kết junction/symlink giữa thư mục downloads "
+        "và thư mục Arma 3.\n"
+        "Status — xem liên kết hiện có.  "
+        "Link — tạo junction còn thiếu.  "
+        "Unlink — xóa junction (tệp mod KHÔNG bị xóa)."
+    ),
+    "tools.lm_warn":                 (
+        "⚠  Unlink xóa liên kết junction khỏi thư mục Arma 3. "
+        "Tệp mod trong downloads/ KHÔNG bị xóa."
+    ),
+    "tools.lm_show_status":          "Xem trạng thái",
+    "tools.lm_create_links":         "Tạo liên kết",
+    "tools.lm_remove_links":         "Xóa liên kết",
+    "tools.lm_no_group_title":       "Chưa chọn nhóm",
+    "tools.lm_no_group_body":        "Vui lòng chọn một nhóm từ danh sách.",
+    "tools.lm_confirm_title":        "Xác nhận xóa liên kết",
+    "tools.lm_confirm_body":         (
+        "Xóa liên kết junction cho nhóm '{group}'?\n\n"
+        "Thao tác này xóa liên kết khỏi thư mục Arma 3 "
+        "nhưng KHÔNG xóa tệp mod trong downloads/."
+    ),
+
+    # ── Tools — Sync Missing ─────────────────────────────────────────────────
+    "tools.sm_desc":                 (
+        "Thử tải lại các mod bị thiếu trên máy chủ khi chạy pipeline lần trước. "
+        "Kiểm tra lại máy chủ và tải về nếu mod đã xuất hiện."
+    ),
+    "tools.sm_btn":                  "Chạy đồng bộ mod thiếu",
+    "tools.sm_count":                "{count} mod đang được liệt kê là thiếu.",
+    "tools.sm_no_report":            "Chưa có missing_report.json — hãy chạy pipeline trước.",
+
+    # ── Tools — Report Missing ───────────────────────────────────────────────
+    "tools.rm_desc":                 (
+        "Kiểm tra mod nào trong comparison.json không có trên máy chủ. "
+        "Lưu missing_report.json để theo dõi mod cần bổ sung."
+    ),
+    "tools.rm_btn":                  "Tạo báo cáo",
+    "tools.rm_last":                 "Tạo lần cuối: {ts}",
+    "tools.rm_none":                 "Chưa có báo cáo.",
+
+    # ── Tools — Clean Orphans ────────────────────────────────────────────────
+    "tools.oc_desc":                 (
+        "Quét thư mục downloads để tìm các thư mục mod không còn được "
+        "tham chiếu trong comparison.json.  Các mod mồ côi này tích tụ khi "
+        "bạn xóa mod khỏi preset và chạy lại pipeline.  "
+        "Chọn các thư mục muốn xóa để giải phóng dung lượng."
+    ),
+    "tools.oc_warn":                 (
+        "⚠  Xóa mod mồ côi sẽ xóa vĩnh viễn tệp mod khỏi ổ đĩa. "
+        "Thao tác này không thể hoàn tác."
+    ),
+    "tools.oc_scan_btn":             "Quét mod mồ côi",
+    "tools.oc_scanning":             "Đang quét…",
+    "tools.oc_no_config":            "Chưa tìm thấy cấu hình. Vui lòng hoàn thành thiết lập.",
+    "tools.oc_no_comparison":        "Chưa có comparison.json — hãy chạy pipeline trước.",
+    "tools.oc_none_found":           "Không tìm thấy mod mồ côi.  Thư mục downloads sạch.",
+    "tools.oc_found":                "Tìm thấy {count} mod mồ côi — tổng {size}",
+    "tools.oc_sel_all":              "Chọn tất cả",
+    "tools.oc_sel_none":             "Bỏ chọn",
+    "tools.oc_delete_btn":           "Xóa đã chọn",
+    "tools.oc_confirm_title":        "Xác nhận xóa",
+    "tools.oc_confirm_body":         (
+        "Xóa vĩnh viễn {count} thư mục mồ côi ({size})?\n\n"
+        "Thao tác này không thể hoàn tác."
+    ),
+    "tools.oc_done":                 "Đã xóa {count} thư mục, giải phóng {size}.",
+    "tools.oc_error":                "Lỗi khi xóa {path}: {e}",
+    "tools.oc_error_title":          "Lỗi xóa",
+    "tools.oc_scan_error":           "Lỗi quét: {e}",
+}
+
+# Guard: both dicts must have identical key sets
+assert set(_EN.keys()) == set(_VI.keys()), (
+    "EN/VI key mismatch: "
+    + str(set(_EN.keys()) ^ set(_VI.keys()))
+)
+
+_STRINGS: dict[str, dict[str, str]] = {"en": _EN, "vi": _VI}
+
+
+def set_language(lang: str) -> None:
+    """Set the active language.  Unknown codes fall back to English."""
+    global _LANG
+    _LANG = lang if lang in _STRINGS else "en"
+
+
+def get_language() -> str:
+    """Return the currently active language code."""
+    return _LANG
+
+
+def t(key: str, **kwargs: object) -> str:
+    """Look up *key* in the active language, falling back to English then the key itself.
+
+    Dynamic placeholders use str.format_map with keyword arguments::
+
+        t("dashboard.sel_count", n_sel=2, n_total=5)
+        # dict entry: "{n_sel} of {n_total} selected"
+    """
+    text = _STRINGS[_LANG].get(key) or _STRINGS["en"].get(key, key)
+    if kwargs:
+        try:
+            return text.format_map(kwargs)
+        except (KeyError, IndexError):
+            return text
+    return text

gui/views/dashboard.py

@@ -11,6 +11,7 @@ import customtkinter as ctk
 from gui._constants import (
     COLOR_OK, COLOR_PENDING, COLOR_ERROR, COLOR_WARN,
 )
+from gui.locales import t
 from gui.views.base import BaseView
 
 if TYPE_CHECKING:
@@ -38,10 +39,12 @@ class DashboardView(BaseView):
         # ── Header ────────────────────────────────────────────────────────────
         hdr = ctk.CTkFrame(self, fg_color="transparent")
         hdr.grid(row=0, column=0, sticky="ew", padx=24, pady=(20, 10))
-        ctk.CTkLabel(hdr, text="Dashboard",
-                     font=ctk.CTkFont(size=22, weight="bold")).pack(side="left")
-        ctk.CTkButton(hdr, text="⟳  Refresh", width=100,
-                      command=self.refresh).pack(side="right")
+        self._title_lbl = ctk.CTkLabel(hdr, text=t("dashboard.title"),
+                                       font=ctk.CTkFont(size=22, weight="bold"))
+        self._title_lbl.pack(side="left")
+        self._refresh_btn = ctk.CTkButton(hdr, text=t("dashboard.refresh_btn"),
+                                          width=100, command=self.refresh)
+        self._refresh_btn.pack(side="right")
 
         # ── Cards ─────────────────────────────────────────────────────────────
         cards = ctk.CTkFrame(self, fg_color="transparent")
@@ -58,7 +61,7 @@ class DashboardView(BaseView):
 
         self._run_btn = ctk.CTkButton(
             run_area,
-            text="▶   Run Full Pipeline",
+            text=t("dashboard.run_btn"),
             font=ctk.CTkFont(size=15, weight="bold"),
             height=46,
             command=self._on_run,
@@ -72,11 +75,11 @@ class DashboardView(BaseView):
         pc = ctk.CTkFrame(parent)
         pc.grid(row=0, column=0, sticky="nsew", padx=(0, 8), pady=4)
 
-        ctk.CTkLabel(pc, text="Preset Files",
+        ctk.CTkLabel(pc, text=t("dashboard.preset_card_title"),
                      font=ctk.CTkFont(size=14, weight="bold")).pack(
             anchor="w", padx=14, pady=(14, 2))
         ctk.CTkLabel(pc,
-                     text="HTML exports from Arma 3 Launcher → Mods → Export to HTML",
+                     text=t("dashboard.preset_card_desc"),
                      text_color="gray", font=ctk.CTkFont(size=11)).pack(
             anchor="w", padx=14)
 
@@ -89,16 +92,16 @@ class DashboardView(BaseView):
         self._sel_count_lbl = ctk.CTkLabel(sel_row, text="", text_color="gray",
                                            font=ctk.CTkFont(size=11))
         self._sel_count_lbl.pack(side="left")
-        ctk.CTkButton(sel_row, text="None", width=54,
+        ctk.CTkButton(sel_row, text=t("dashboard.btn_none"), width=54,
                       fg_color="transparent", border_width=1,
                       text_color=("gray10", "gray90"), font=ctk.CTkFont(size=11),
                       command=self._select_none).pack(side="right")
-        ctk.CTkButton(sel_row, text="All", width=54,
+        ctk.CTkButton(sel_row, text=t("dashboard.btn_all"), width=54,
                       fg_color="transparent", border_width=1,
                       text_color=("gray10", "gray90"), font=ctk.CTkFont(size=11),
                       command=self._select_all).pack(side="right", padx=(0, 6))
 
-        ctk.CTkButton(pc, text="+ Add Preset Files",
+        ctk.CTkButton(pc, text=t("dashboard.btn_add"),
                       fg_color="transparent", border_width=1,
                       text_color=("gray10", "gray90"),
                       command=self._add_presets).pack(pady=(0, 14))
@@ -109,16 +112,17 @@ class DashboardView(BaseView):
         pipe = ctk.CTkFrame(parent)
         pipe.grid(row=0, column=1, sticky="nsew", padx=(8, 0), pady=4)
 
-        ctk.CTkLabel(pipe, text="Pipeline Status",
+        ctk.CTkLabel(pipe, text=t("dashboard.pipeline_title"),
                      font=ctk.CTkFont(size=14, weight="bold")).pack(
             anchor="w", padx=14, pady=(14, 8))
 
         self._step_icons: dict[str, ctk.CTkLabel] = {}
-        for key, label in [
-            ("parse",    "Parse presets"),
-            ("compare",  "Compare presets"),
-            ("download", "Download mods"),
-            ("link",     "Link to Arma"),
+        self._step_labels: dict[str, ctk.CTkLabel] = {}
+        for key, lbl_key in [
+            ("parse",    "dashboard.step_parse"),
+            ("compare",  "dashboard.step_compare"),
+            ("download", "dashboard.step_download"),
+            ("link",     "dashboard.step_link"),
         ]:
             row = ctk.CTkFrame(pipe, fg_color="transparent")
             row.pack(fill="x", padx=14, pady=3)
@@ -126,8 +130,10 @@ class DashboardView(BaseView):
                                 text_color=COLOR_PENDING,
                                 font=ctk.CTkFont(size=15))
             icon.pack(side="left")
-            ctk.CTkLabel(row, text=label, anchor="w").pack(side="left", padx=6)
+            lbl = ctk.CTkLabel(row, text=t(lbl_key), anchor="w")
+            lbl.pack(side="left", padx=6)
             self._step_icons[key]  = icon
+            self._step_labels[key] = lbl
 
         self._stats_lbl = ctk.CTkLabel(pipe, text="", text_color="gray",
                                        font=ctk.CTkFont(size=11),
@@ -137,6 +143,22 @@ class DashboardView(BaseView):
     # ── refresh ───────────────────────────────────────────────────────────────
 
     def refresh(self) -> None:
+        # Retranslate static widgets that were built once
+        self._title_lbl.configure(text=t("dashboard.title"))
+        self._refresh_btn.configure(text=t("dashboard.refresh_btn"))
+        # Only update run_btn text when not currently running
+        if self._run_btn.cget("state") != "disabled":
+            self._run_btn.configure(text=t("dashboard.run_btn"))
+        # Retranslate step labels
+        for key, lbl_key in [
+            ("parse",    "dashboard.step_parse"),
+            ("compare",  "dashboard.step_compare"),
+            ("download", "dashboard.step_download"),
+            ("link",     "dashboard.step_link"),
+        ]:
+            if key in self._step_labels:
+                self._step_labels[key].configure(text=t(lbl_key))
+
         self._rebuild_preset_list()
         self._update_pipeline_status()
 
@@ -148,21 +170,21 @@ class DashboardView(BaseView):
         cfg = self.app.cfg
         if not cfg:
             ctk.CTkLabel(self._preset_scroll,
-                         text="No config found. Complete Setup first.",
+                         text=t("dashboard.no_config"),
                          text_color=COLOR_WARN).pack(anchor="w")
             return
 
         html_dir = cfg.modlist_html
         if not html_dir.is_dir():
             ctk.CTkLabel(self._preset_scroll,
-                         text=f"Folder missing:\n{html_dir}",
+                         text=t("dashboard.folder_missing", path=html_dir),
                          text_color=COLOR_WARN, justify="left").pack(padx=4, pady=8)
             return
 
         files = sorted(html_dir.glob("*.html"))
         if not files:
             ctk.CTkLabel(self._preset_scroll,
-                         text="No preset files yet.\nUse the button below to add them.",
+                         text=t("dashboard.no_presets"),
                          text_color="gray", justify="left").pack(padx=4, pady=8)
             return
 
@@ -207,9 +229,9 @@ class DashboardView(BaseView):
                 if cfg.missing_report.exists():
                     rep = json.loads(cfg.missing_report.read_text(encoding="utf-8"))
                     missing = rep.get("missing", 0)
-                stat = f"{total} mods · {shared} shared"
+                stat = t("dashboard.stats", total=total, shared=shared)
                 if missing:
-                    stat += f"\n{missing} missing from server"
+                    stat += t("dashboard.stats_missing", missing=missing)
                 self._stats_lbl.configure(text=stat)
             except Exception:
                 pass
@@ -236,7 +258,9 @@ class DashboardView(BaseView):
                    COLOR_WARN  if n_sel == 1 else
                    COLOR_ERROR)
         self._sel_count_lbl.configure(
-            text=f"{n_sel} of {n_total} selected", text_color=color)
+            text=t("dashboard.sel_count", n_sel=n_sel, n_total=n_total),
+            text_color=color,
+        )
 
     def _select_all(self) -> None:
         for var in self._preset_checks.values():
@@ -253,11 +277,11 @@ class DashboardView(BaseView):
     def _add_presets(self) -> None:
         cfg = self.app.cfg
         if not cfg:
-            messagebox.showwarning("Setup required",
-                                   "Please complete Setup before adding presets.")
+            messagebox.showwarning(t("dashboard.dlg_setup_title"),
+                                   t("dashboard.dlg_setup_body"))
             return
         files = filedialog.askopenfilenames(
-            title="Select Arma 3 Launcher preset files",
+            title=t("dashboard.file_dialog_title"),
             filetypes=[("HTML Preset", "*.html"), ("All files", "*.*")],
         )
         if not files:
@@ -280,10 +304,10 @@ class DashboardView(BaseView):
     def set_pipeline_ui(self, running: bool) -> None:
         """Called by the app to reflect pipeline start/end in the UI."""
         if running:
-            self._run_btn.configure(state="disabled", text="Running…")
+            self._run_btn.configure(state="disabled", text=t("dashboard.running"))
             self._prog.pack(fill="x", pady=(6, 0))
             self._prog.start()
         else:
-            self._run_btn.configure(state="normal", text="▶   Run Full Pipeline")
+            self._run_btn.configure(state="normal", text=t("dashboard.run_btn"))
             self._prog.stop()
             self._prog.pack_forget()

gui/views/logs.py

@@ -5,6 +5,7 @@ from typing import TYPE_CHECKING
 import customtkinter as ctk
 
 from gui._constants import COLOR_ERROR
+from gui.locales import t
 from gui.views.base import BaseView
 
 if TYPE_CHECKING:
@@ -27,16 +28,19 @@ class LogsView(BaseView):
         # ── Header ────────────────────────────────────────────────────────────
         hdr = ctk.CTkFrame(self, fg_color="transparent")
         hdr.grid(row=0, column=0, sticky="ew", padx=24, pady=(20, 8))
-        ctk.CTkLabel(hdr, text="Logs",
-                     font=ctk.CTkFont(size=22, weight="bold")).pack(side="left")
+        self._title_lbl = ctk.CTkLabel(hdr, text=t("logs.title"),
+                                       font=ctk.CTkFont(size=22, weight="bold"))
+        self._title_lbl.pack(side="left")
 
         btn_row = ctk.CTkFrame(hdr, fg_color="transparent")
         btn_row.pack(side="right")
-        ctk.CTkButton(btn_row, text="Copy", width=72,
-                      command=self._copy).pack(side="left", padx=4)
-        ctk.CTkButton(btn_row, text="Clear", width=72,
+        self._copy_btn = ctk.CTkButton(btn_row, text=t("logs.copy_btn"), width=72,
+                                       command=self._copy)
+        self._copy_btn.pack(side="left", padx=4)
+        self._clear_btn = ctk.CTkButton(btn_row, text=t("logs.clear_btn"), width=72,
                                         fg_color=COLOR_ERROR, hover_color="#c62828",
-                      command=self._clear).pack(side="left")
+                                        command=self._clear)
+        self._clear_btn.pack(side="left")
 
         # ── Log textbox (persistent) ──────────────────────────────────────────
         self._log_box = ctk.CTkTextbox(
@@ -44,6 +48,12 @@ class LogsView(BaseView):
             font=ctk.CTkFont(family="Consolas", size=12))
         self._log_box.grid(row=1, column=0, sticky="nsew", padx=24, pady=(0, 12))
 
+    def refresh(self) -> None:
+        # Retranslate header widgets (log content intentionally preserved)
+        self._title_lbl.configure(text=t("logs.title"))
+        self._copy_btn.configure(text=t("logs.copy_btn"))
+        self._clear_btn.configure(text=t("logs.clear_btn"))
+
     def append(self, text: str) -> None:
         """Thread-safe-ish: called from the app's after() poll loop (main thread)."""
         try:

gui/views/mods.py

@@ -7,24 +7,50 @@ from typing import TYPE_CHECKING, Optional
 
 import customtkinter as ctk
 
+from arma_modlist_tools.fetcher import _normalize_name, _parse_meta_cpp
 from gui._constants import COLOR_OK, COLOR_ERROR, COLOR_WARN, COLOR_RUNNING
+from gui.locales import t
 from gui.views.base import BaseView
 
 if TYPE_CHECKING:
     from gui.app import ArmaModManagerApp
 
 
-def _find_folder(group_dir: Path, mod_name: str) -> Optional[Path]:
-    """Return the local mod folder path, or None if not downloaded."""
+def _find_folder(group_dir: Path, mod_name: str, steam_id: str | None = None) -> Optional[Path]:
+    """Return the local mod folder path, or None if not downloaded.
+
+    Matches in priority order:
+    1. Exact folder name ``@{mod_name}``
+    2. Case-insensitive name (handles ``@CBA_A3`` vs ``CBA_A3``)
+    3. Normalized name — strips non-alphanumeric (handles ``@cba_a3`` vs ``CBA A3``)
+    4. Steam ID match via ``meta.cpp`` ``publishedid`` field (folder name differs from modlist name)
+    """
     if not group_dir.is_dir():
         return None
     candidate = group_dir / f"@{mod_name}"
     if candidate.is_dir():
         return candidate
-    target = mod_name.lower()
+    target_lower = mod_name.lower()
+    target_norm  = _normalize_name(mod_name)
     for p in group_dir.iterdir():
-        if p.is_dir() and p.name.lstrip("@").lower() == target:
+        if not p.is_dir():
+            continue
+        if p.name.lstrip("@").lower() == target_lower:
             return p
+        if _normalize_name(p.name) == target_norm:
+            return p
+    # Fallback: match by steam_id via meta.cpp when folder name diverges from modlist name
+    if steam_id:
+        for p in group_dir.iterdir():
+            if not p.is_dir():
+                continue
+            meta = p / "meta.cpp"
+            try:
+                sid = _parse_meta_cpp(meta.read_text(encoding="utf-8", errors="replace"))
+                if sid == steam_id:
+                    return p
+            except OSError:
+                pass
     return None
 
 
@@ -49,18 +75,19 @@ class ModsView(BaseView):
         hdr.grid(row=0, column=0, sticky="ew", padx=24, pady=(20, 6))
         hdr.columnconfigure(1, weight=1)
 
-        ctk.CTkLabel(hdr, text="Mods",
-                     font=ctk.CTkFont(size=22, weight="bold")).grid(
-            row=0, column=0, sticky="w")
+        self._title_lbl = ctk.CTkLabel(hdr, text=t("mods.title"),
+                                       font=ctk.CTkFont(size=22, weight="bold"))
+        self._title_lbl.grid(row=0, column=0, sticky="w")
 
         btn_frame = ctk.CTkFrame(hdr, fg_color="transparent")
         btn_frame.grid(row=0, column=2, sticky="e")
 
-        ctk.CTkButton(btn_frame, text="⟳  Refresh", width=100,
-                      command=self.refresh).pack(side="left", padx=(0, 6))
+        self._refresh_btn = ctk.CTkButton(btn_frame, text=t("mods.refresh_btn"),
+                                          width=100, command=self.refresh)
+        self._refresh_btn.pack(side="left", padx=(0, 6))
 
         self._check_btn = ctk.CTkButton(
-            btn_frame, text="☁  Check Updates", width=130,
+            btn_frame, text=t("mods.check_btn"), width=140,
             command=self._check_updates,
         )
         self._check_btn.pack(side="left")
@@ -68,9 +95,10 @@ class ModsView(BaseView):
         # ── Search ────────────────────────────────────────────────────────────
         bar = ctk.CTkFrame(self, fg_color="transparent")
         bar.grid(row=1, column=0, sticky="ew", padx=24, pady=(0, 8))
-        ctk.CTkLabel(bar, text="Search:").pack(side="left", padx=(0, 6))
+        self._search_lbl = ctk.CTkLabel(bar, text=t("mods.search_label"))
+        self._search_lbl.pack(side="left", padx=(0, 6))
         ctk.CTkEntry(bar, textvariable=self._search_var,
-                     placeholder_text="Filter mods in active tab…",
+                     placeholder_text=t("mods.search_placeholder"),
                      width=220).pack(side="left")
         self._search_var.trace_add("write", lambda *_: self._apply_search())
 
@@ -87,6 +115,13 @@ class ModsView(BaseView):
     # =========================================================================
 
     def refresh(self) -> None:
+        # Retranslate static header widgets
+        self._title_lbl.configure(text=t("mods.title"))
+        self._refresh_btn.configure(text=t("mods.refresh_btn"))
+        if not self._checking:
+            self._check_btn.configure(text=t("mods.check_btn"))
+        self._search_lbl.configure(text=t("mods.search_label"))
+
         self._mod_rows.clear()
 
         # Destroy previous tab_view / message
@@ -99,19 +134,16 @@ class ModsView(BaseView):
 
         cfg = self.app.cfg
         if not cfg:
-            self._show_msg("No config found. Complete Setup first.")
+            self._show_msg(t("mods.no_config"))
             return
         if not cfg.comparison.exists():
-            self._show_msg(
-                "No mod data yet.\n"
-                "Go to Dashboard, select your presets, then click Run Full Pipeline."
-            )
+            self._show_msg(t("mods.no_data"))
             return
 
         try:
             comp = json.loads(cfg.comparison.read_text(encoding="utf-8"))
         except Exception as e:
-            self._show_msg(f"Error reading comparison.json: {e}", error=True)
+            self._show_msg(t("mods.read_error", e=e), error=True)
             return
 
         # Build ordered group list: shared first, then unique groups
@@ -152,19 +184,22 @@ class ModsView(BaseView):
                                    fg_color=("gray82", "gray22"), corner_radius=6)
             col_hdr.grid(row=0, column=0, sticky="ew", padx=4, pady=(6, 2))
             col_hdr.columnconfigure(0, weight=1)
-            for col, (w, lbl) in enumerate([
-                (0,   "Mod Name"),
-                (80,  "Downloaded"),
-                (80,  "Linked"),
-                (160, "Server Status"),
-                (80,  ""),
+            for col, (w, lbl_key, anc) in enumerate([
+                (0,   "mods.col_name",       "w"),
+                (80,  "mods.col_downloaded",  "center"),
+                (80,  "mods.col_linked",      "center"),
+                (160, "mods.col_server",      "w"),
+                (80,  "",                     "center"),
             ]):
-                ctk.CTkLabel(col_hdr, text=lbl,
+                ctk.CTkLabel(col_hdr, text=t(lbl_key) if lbl_key else "",
                              font=ctk.CTkFont(weight="bold"),
-                             anchor="w", width=w or 1).grid(
+                             anchor=anc, width=w or 1).grid(
                     row=0, column=col,
-                    padx=(10 if col == 0 else 4, 4), pady=5,
+                    padx=(8 if col == 0 else 4, 4), pady=5,
                     sticky="ew" if col == 0 else "")
+            # Spacer compensates for CTkScrollableFrame's internal scrollbar width
+            # so the header columns line up with the data rows below.
+            ctk.CTkLabel(col_hdr, text="", width=16).grid(row=0, column=5, padx=0)
 
             # Scrollable rows
             scroll = ctk.CTkScrollableFrame(tab_frame)
@@ -196,7 +231,7 @@ class ModsView(BaseView):
         link_map: dict[str, bool],
     ) -> None:
         for i, mod in enumerate(sorted(mods, key=lambda m: m["name"].lower())):
-            folder_path = _find_folder(cfg.downloads / group, mod["name"])
+            folder_path = _find_folder(cfg.downloads / group, mod["name"], mod.get("steam_id"))
             downloaded  = folder_path is not None
             linked      = (link_map.get(folder_path.name.lower(), False)
                            if folder_path else False)
@@ -207,23 +242,23 @@ class ModsView(BaseView):
             row.columnconfigure(0, weight=1)
 
             # Mod name
-            name_lbl = ctk.CTkLabel(row, text=f"  {mod['name']}", anchor="w")
-            name_lbl.grid(row=0, column=0, sticky="ew", padx=4, pady=3)
+            name_lbl = ctk.CTkLabel(row, text=mod["name"], anchor="w")
+            name_lbl.grid(row=0, column=0, sticky="ew", padx=(8, 4), pady=3)
 
             # Downloaded
             ctk.CTkLabel(
                 row,
-                text="  ✓" if downloaded else "  ✗",
+                text="✓" if downloaded else "✗",
                 text_color=COLOR_OK if downloaded else COLOR_ERROR,
-                width=80, anchor="w",
+                width=80, anchor="center",
             ).grid(row=0, column=1, padx=4)
 
             # Linked
             ctk.CTkLabel(
                 row,
-                text="  ✓" if linked else ("  —" if not downloaded else "  ✗"),
+                text="✓" if linked else ("—" if not downloaded else "✗"),
                 text_color=COLOR_OK if linked else "gray",
-                width=80, anchor="w",
+                width=80, anchor="center",
             ).grid(row=0, column=2, padx=4)
 
             # Server status
@@ -235,7 +270,7 @@ class ModsView(BaseView):
             # Update button (hidden until stale detected)
             folder_name = folder_path.name if folder_path else None
             update_btn = ctk.CTkButton(
-                row, text="Update", width=70,
+                row, text=t("mods.update_btn"), width=80,
                 command=(lambda g=group, fn=folder_name:
                          self._update_mod(g, fn)) if folder_name else None,
                 state="normal" if folder_name else "disabled",
@@ -270,13 +305,13 @@ class ModsView(BaseView):
             return
 
         self._checking = True
-        self._check_btn.configure(text="Checking…", state="disabled")
+        self._check_btn.configure(text=t("mods.check_btn_checking"), state="disabled")
 
         # Reset downloaded rows to "Checking…"
         for row in self._mod_rows.values():
             if row["folder_path"]:
                 row["status_label"].configure(
-                    text="Checking…", text_color=COLOR_RUNNING)
+                    text=t("mods.status_checking"), text_color=COLOR_RUNNING)
             else:
                 row["status_label"].configure(text="—", text_color="gray")
 
@@ -313,27 +348,29 @@ class ModsView(BaseView):
         threading.Thread(target=worker, daemon=True).start()
 
     def _apply_check_results(self, results: dict[str, tuple[str, int]]) -> None:
+        # Build status map from current translations
         _STATUS: dict[str, tuple[str, str]] = {
-            "ok":             ("✓ Up to date",  COLOR_OK),
-            "stale":          ("⚠ {n} outdated", COLOR_WARN),
-            "not_downloaded": ("—",              "gray"),
-            "not_on_server":  ("Not on server",  "gray"),
-            "error":          ("✗ Error",        COLOR_ERROR),
+            "ok":             (t("mods.status_ok"),             COLOR_OK),
+            "stale":          (t("mods.status_stale"),          COLOR_WARN),
+            "not_downloaded": (t("mods.status_not_downloaded"),  "gray"),
+            "not_on_server":  (t("mods.status_not_on_server"),   "gray"),
+            "error":          (t("mods.status_error"),           COLOR_ERROR),
         }
         for key, (status, n) in results.items():
             row = self._mod_rows.get(key)
             if not row:
                 continue
             tmpl, color = _STATUS.get(status, ("—", "gray"))
-            row["status_label"].configure(
-                text=tmpl.replace("{n}", str(n)), text_color=color)
+            # For "stale", the template contains {n} placeholder
+            text = tmpl.format_map({"n": n}) if "{n}" in tmpl else tmpl
+            row["status_label"].configure(text=text, text_color=color)
             if status == "stale" and row["folder_path"]:
                 row["update_btn"].grid()
             else:
                 row["update_btn"].grid_remove()
 
         self._checking = False
-        self._check_btn.configure(text="☁  Check Updates", state="normal")
+        self._check_btn.configure(text=t("mods.check_btn"), state="normal")
 
     def _update_mod(self, group: str, folder_name: str) -> None:
         self.app.navigate_to("Logs")

gui/views/settings.py

@@ -4,6 +4,7 @@ from typing import TYPE_CHECKING
 
 import customtkinter as ctk
 
+from gui.locales import t
 from gui.views.base import BaseView
 
 if TYPE_CHECKING:
@@ -11,15 +12,15 @@ if TYPE_CHECKING:
 
 
 class SettingsView(BaseView):
-    """Appearance switcher, wizard re-opener, and current config display."""
+    """Appearance switcher, language selector, wizard re-opener, and current config display."""
 
     def build(self) -> None:
         self.grid_columnconfigure(0, weight=1)
         self.grid_rowconfigure(1, weight=1)
 
-        ctk.CTkLabel(self, text="Settings",
-                     font=ctk.CTkFont(size=22, weight="bold")).grid(
-            row=0, column=0, sticky="w", padx=24, pady=(20, 8))
+        self._title_lbl = ctk.CTkLabel(self, text=t("settings.title"),
+                                       font=ctk.CTkFont(size=22, weight="bold"))
+        self._title_lbl.grid(row=0, column=0, sticky="w", padx=24, pady=(20, 8))
 
         self._scroll = ctk.CTkScrollableFrame(self, fg_color="transparent")
         self._scroll.grid(row=1, column=0, sticky="nsew", padx=24, pady=(0, 12))
@@ -27,7 +28,8 @@ class SettingsView(BaseView):
         self._build_cards()
 
     def refresh(self) -> None:
-        # Config info may have changed (e.g. after wizard); rebuild cards.
+        # Config info and language may have changed; rebuild everything.
+        self._title_lbl.configure(text=t("settings.title"))
         for w in self._scroll.winfo_children():
             w.destroy()
         self._build_cards()
@@ -36,22 +38,21 @@ class SettingsView(BaseView):
         # ── Server & Paths ────────────────────────────────────────────────────
         c1 = ctk.CTkFrame(self._scroll)
         c1.pack(fill="x", pady=6)
-        ctk.CTkLabel(c1, text="Server & Path Configuration",
+        ctk.CTkLabel(c1, text=t("settings.server_card_title"),
                      font=ctk.CTkFont(size=14, weight="bold")).pack(
             anchor="w", padx=16, pady=(14, 3))
         ctk.CTkLabel(c1,
-                     text="Re-run the setup wizard to change your server URL, "
-                          "credentials, or Arma folder.",
+                     text=t("settings.server_card_desc"),
                      text_color="gray", wraplength=600, justify="left").pack(
             anchor="w", padx=16, pady=(0, 8))
-        ctk.CTkButton(c1, text="Open Setup Wizard", width=160,
+        ctk.CTkButton(c1, text=t("settings.wizard_btn"), width=160,
                       command=self.app.open_wizard).pack(
             anchor="e", padx=16, pady=(0, 14))
 
         # ── Appearance ────────────────────────────────────────────────────────
         c2 = ctk.CTkFrame(self._scroll)
         c2.pack(fill="x", pady=6)
-        ctk.CTkLabel(c2, text="Appearance",
+        ctk.CTkLabel(c2, text=t("settings.appearance_title"),
                      font=ctk.CTkFont(size=14, weight="bold")).pack(
             anchor="w", padx=16, pady=(14, 3))
         mode_var = ctk.StringVar(value=ctk.get_appearance_mode())
@@ -60,12 +61,28 @@ class SettingsView(BaseView):
                           command=ctk.set_appearance_mode,
                           width=140).pack(anchor="w", padx=16, pady=(0, 14))
 
+        # ── Language ──────────────────────────────────────────────────────────
+        c_lang = ctk.CTkFrame(self._scroll)
+        c_lang.pack(fill="x", pady=6)
+        ctk.CTkLabel(c_lang, text=t("settings.language_title"),
+                     font=ctk.CTkFont(size=14, weight="bold")).pack(
+            anchor="w", padx=16, pady=(14, 3))
+        from gui.locales import get_language
+        current_display = "Tiếng Việt" if get_language() == "vi" else "English"
+        ctk.CTkOptionMenu(
+            c_lang,
+            values=["English", "Tiếng Việt"],
+            variable=ctk.StringVar(value=current_display),
+            command=lambda v: self.app.switch_language("vi" if v == "Tiếng Việt" else "en"),
+            width=160,
+        ).pack(anchor="w", padx=16, pady=(0, 14))
+
         # ── Current config info ───────────────────────────────────────────────
         cfg = self.app.cfg
         if cfg:
             c3 = ctk.CTkFrame(self._scroll)
             c3.pack(fill="x", pady=6)
-            ctk.CTkLabel(c3, text="Current Configuration",
+            ctk.CTkLabel(c3, text=t("settings.config_title"),
                          font=ctk.CTkFont(size=14, weight="bold")).pack(
                 anchor="w", padx=16, pady=(14, 3))
             info = (

gui/views/tools.py

@@ -1,12 +1,17 @@
 from __future__ import annotations
 
 import json
+import shutil
+import threading
 from tkinter import messagebox
-from typing import TYPE_CHECKING, Optional
+from typing import TYPE_CHECKING
 
 import customtkinter as ctk
 
+from arma_modlist_tools.cleaner import find_orphan_folders
+from arma_modlist_tools.linker import _is_junction, remove_junction
 from gui._constants import COLOR_WARN, PROJECT_ROOT
+from gui.locales import t
 from gui.views.base import BaseView
 
 if TYPE_CHECKING:
@@ -22,9 +27,9 @@ class ToolsView(BaseView):
         self.grid_columnconfigure(0, weight=1)
         self.grid_rowconfigure(1, weight=1)
 
-        ctk.CTkLabel(self, text="Tools",
-                     font=ctk.CTkFont(size=22, weight="bold")).grid(
-            row=0, column=0, sticky="w", padx=24, pady=(20, 8))
+        self._title_lbl = ctk.CTkLabel(self, text=t("tools.title"),
+                                       font=ctk.CTkFont(size=22, weight="bold"))
+        self._title_lbl.grid(row=0, column=0, sticky="w", padx=24, pady=(20, 8))
 
         self._tab_view = ctk.CTkTabview(self)
         self._tab_view.grid(row=1, column=0, sticky="nsew", padx=16, pady=(0, 12))
@@ -32,34 +37,47 @@ class ToolsView(BaseView):
         # Per-tab group menu references so refresh() can repopulate them all
         self._group_menus: list[tuple[ctk.CTkOptionMenu, ctk.StringVar]] = []
 
+        # Tab-internal translatable labels (for hot-swap on refresh)
+        self._translatable: list[tuple[ctk.CTkLabel | ctk.CTkButton | ctk.CTkCheckBox, str]] = []
+
         self._build_check_names_tab()
         self._build_update_mods_tab()
         self._build_link_mods_tab()
         self._build_sync_missing_tab()
         self._build_report_missing_tab()
+        self._build_clean_orphans_tab()
 
     # =========================================================================
     # Public
     # =========================================================================
 
     def refresh(self) -> None:
+        self._title_lbl.configure(text=t("tools.title"))
+
+        # Retranslate registered widgets
+        for widget, key in self._translatable:
+            widget.configure(text=t(key))
+
+        # Refresh link-mods button label (depends on current command selection)
+        self._lm_on_change()
+
         groups     = self._get_groups()
-        all_groups = ["All groups"] + groups
+        all_groups = [t("tools.all_groups")] + groups
 
         # Repopulate generic group menus
         for menu, var in self._group_menus:
             prev = var.get()
             menu.configure(values=all_groups)
-            if prev not in all_groups:
-                var.set("All groups")
+            # Keep selection if still valid, else reset to "All groups"
+            if prev not in all_groups and prev not in groups:
+                var.set(t("tools.all_groups"))
 
         # Link Mods group menu (no "All groups")
         lm_prev = self._lm_group_var.get()
-        lm_vals = groups if groups else ["(no groups found)"]
+        lm_vals = groups if groups else [t("tools.no_groups")]
         self._lm_group_menu.configure(values=lm_vals)
         if lm_prev not in lm_vals:
             self._lm_group_var.set(lm_vals[0])
-        self._lm_on_change()   # re-evaluate button state
 
         # Info labels
         self._update_sm_label()
@@ -70,47 +88,49 @@ class ToolsView(BaseView):
     # =========================================================================
 
     def _build_check_names_tab(self) -> None:
+        # Tab name kept in English — used as CTkTabview lookup key
         self._tab_view.add("Check Names")
         tab = self._tab_view.tab("Check Names")
         tab.grid_columnconfigure(0, weight=1)
 
-        _desc(tab, row=0,
-              text="Scan mod folders and compare against the server. "
-                   "Reports naming mismatches (MISMATCH), unrecognised folders "
-                   "(NOT_ON_SERVER), and wrong Steam IDs in meta.cpp (ID_COLLISION).")
+        desc_lbl = _desc(tab, row=0, text=t("tools.cn_desc"))
+        self._translatable.append((desc_lbl, "tools.cn_desc"))
 
         # Group
-        gf = _row(tab, row=1, label="Group:")
-        self._cn_group_var = ctk.StringVar(value="All groups")
+        gf, group_lbl = _row(tab, row=1, label=t("tools.label_group"))
+        self._translatable.append((group_lbl, "tools.label_group"))
+        self._cn_group_var = ctk.StringVar(value=t("tools.all_groups"))
         menu = ctk.CTkOptionMenu(gf, variable=self._cn_group_var,
-                                 values=["All groups"], width=200)
+                                 values=[t("tools.all_groups")], width=200)
         menu.pack(side="left")
         self._group_menus.append((menu, self._cn_group_var))
 
         # Checkboxes
-        cf = _row(tab, row=2, label="Options:")
+        cf, opts_lbl = _row(tab, row=2, label=t("tools.label_options"))
+        self._translatable.append((opts_lbl, "tools.label_options"))
         self._cn_fix_var     = ctk.BooleanVar(value=False)
         self._cn_fix_ids_var = ctk.BooleanVar(value=False)
-        ctk.CTkCheckBox(cf, text="Auto-fix folder name mismatches  (--fix)",
+        cn_fix_chk = ctk.CTkCheckBox(cf, text=t("tools.cn_fix_chk"),
                                      variable=self._cn_fix_var,
-                        command=self._cn_on_toggle).pack(side="left", padx=(0, 16))
-        ctk.CTkCheckBox(cf, text="Auto-fix wrong Steam IDs in meta.cpp  (--fix-ids)",
+                                     command=self._cn_on_toggle)
+        cn_fix_chk.pack(side="left", padx=(0, 16))
+        self._translatable.append((cn_fix_chk, "tools.cn_fix_chk"))
+        cn_ids_chk = ctk.CTkCheckBox(cf, text=t("tools.cn_fix_ids_chk"),
                                      variable=self._cn_fix_ids_var,
-                        command=self._cn_on_toggle).pack(side="left")
+                                     command=self._cn_on_toggle)
+        cn_ids_chk.pack(side="left")
+        self._translatable.append((cn_ids_chk, "tools.cn_fix_ids_chk"))
 
         # Warning (hidden until checkbox ticked)
-        self._cn_warn = ctk.CTkLabel(
-            tab,
-            text="⚠  --fix renames folders and updates junctions.  "
-                 "--fix-ids rewrites meta.cpp files.",
-            text_color=_WARN_COLOR, anchor="w",
-        )
-        # not gridded yet — shown on demand
+        self._cn_warn = ctk.CTkLabel(tab, text=t("tools.cn_warn"),
+                                     text_color=_WARN_COLOR, anchor="w")
+        self._translatable.append((self._cn_warn, "tools.cn_warn"))
 
         # Run button
-        ctk.CTkButton(tab, text="Run Check Names", width=180,
-                      command=self._cn_run).grid(
-            row=10, column=0, padx=24, pady=(16, 24), sticky="e")
+        cn_btn = ctk.CTkButton(tab, text=t("tools.cn_btn"), width=180,
+                               command=self._cn_run)
+        cn_btn.grid(row=10, column=0, padx=24, pady=(16, 24), sticky="e")
+        self._translatable.append((cn_btn, "tools.cn_btn"))
 
     def _cn_on_toggle(self) -> None:
         if self._cn_fix_var.get() or self._cn_fix_ids_var.get():
@@ -121,7 +141,7 @@ class ToolsView(BaseView):
     def _cn_run(self) -> None:
         args = ["check_names.py"]
         g = self._cn_group_var.get()
-        if g != "All groups":
+        if g != t("tools.all_groups"):
             args += ["--group", g]
         if self._cn_fix_var.get():
             args.append("--fix")
@@ -136,54 +156,56 @@ class ToolsView(BaseView):
         tab = self._tab_view.tab("Update Mods")
         tab.grid_columnconfigure(0, weight=1)
 
-        _desc(tab, row=0,
-              text="Re-download mod files whose size on the server differs from "
-                   "your local copy.  Use --force to re-download everything "
-                   "regardless of size.")
+        desc_lbl = _desc(tab, row=0, text=t("tools.um_desc"))
+        self._translatable.append((desc_lbl, "tools.um_desc"))
 
         # Group
-        gf = _row(tab, row=1, label="Group:")
-        self._um_group_var = ctk.StringVar(value="All groups")
+        gf, group_lbl = _row(tab, row=1, label=t("tools.label_group"))
+        self._translatable.append((group_lbl, "tools.label_group"))
+        self._um_group_var = ctk.StringVar(value=t("tools.all_groups"))
         um_menu = ctk.CTkOptionMenu(
-            gf, variable=self._um_group_var, values=["All groups"], width=200,
+            gf, variable=self._um_group_var, values=[t("tools.all_groups")], width=200,
             command=self._um_on_group_change,
         )
         um_menu.pack(side="left")
         self._group_menus.append((um_menu, self._um_group_var))
 
         # Mod name (enabled only when a specific group is selected)
-        mf = _row(tab, row=2, label="Mod folder:")
+        mf, mod_lbl = _row(tab, row=2, label=t("tools.um_mod_label"))
+        self._translatable.append((mod_lbl, "tools.um_mod_label"))
         self._um_mod_entry = ctk.CTkEntry(
-            mf, placeholder_text="Optional — e.g. @ace", width=220,
+            mf, placeholder_text=t("tools.um_mod_placeholder"), width=220,
             state="disabled",
         )
         self._um_mod_entry.pack(side="left")
-        ctk.CTkLabel(mf, text="(only when a specific group is selected)",
-                     text_color="gray").pack(side="left", padx=8)
+        um_hint = ctk.CTkLabel(mf, text=t("tools.um_mod_hint"), text_color="gray")
+        um_hint.pack(side="left", padx=8)
+        self._translatable.append((um_hint, "tools.um_mod_hint"))
 
         # Force checkbox
-        ff = _row(tab, row=3, label="Options:")
+        ff, opts_lbl = _row(tab, row=3, label=t("tools.label_options"))
+        self._translatable.append((opts_lbl, "tools.label_options"))
         self._um_force_var = ctk.BooleanVar(value=False)
-        ctk.CTkCheckBox(
-            ff, text="Force re-download all files  (--force)",
+        um_force_chk = ctk.CTkCheckBox(
+            ff, text=t("tools.um_force_chk"),
             variable=self._um_force_var,
             command=self._um_on_toggle,
-        ).pack(side="left")
+        )
+        um_force_chk.pack(side="left")
+        self._translatable.append((um_force_chk, "tools.um_force_chk"))
 
         # Warning
-        self._um_warn = ctk.CTkLabel(
-            tab,
-            text="⚠  --force re-downloads every file regardless of size. "
-                 "This may transfer a large amount of data.",
-            text_color=_WARN_COLOR, anchor="w",
-        )
+        self._um_warn = ctk.CTkLabel(tab, text=t("tools.um_warn"),
+                                     text_color=_WARN_COLOR, anchor="w")
+        self._translatable.append((self._um_warn, "tools.um_warn"))
 
-        ctk.CTkButton(tab, text="Run Update", width=180,
-                      command=self._um_run).grid(
-            row=10, column=0, padx=24, pady=(16, 24), sticky="e")
+        um_btn = ctk.CTkButton(tab, text=t("tools.um_btn"), width=180,
+                               command=self._um_run)
+        um_btn.grid(row=10, column=0, padx=24, pady=(16, 24), sticky="e")
+        self._translatable.append((um_btn, "tools.um_btn"))
 
     def _um_on_group_change(self, _: str) -> None:
-        is_specific = self._um_group_var.get() != "All groups"
+        is_specific = self._um_group_var.get() != t("tools.all_groups")
         self._um_mod_entry.configure(state="normal" if is_specific else "disabled")
         if not is_specific:
             self._um_mod_entry.delete(0, "end")
@@ -197,7 +219,7 @@ class ToolsView(BaseView):
     def _um_run(self) -> None:
         args = ["update_mods.py"]
         g = self._um_group_var.get()
-        if g != "All groups":
+        if g != t("tools.all_groups"):
             args += ["--group", g]
         mod = self._um_mod_entry.get().strip()
         if mod:
@@ -213,15 +235,12 @@ class ToolsView(BaseView):
         tab = self._tab_view.tab("Link Mods")
         tab.grid_columnconfigure(0, weight=1)
 
-        _desc(tab, row=0,
-              text="Manage junction/symlink links between your downloads folder "
-                   "and the Arma 3 directory.\n"
-                   "Status — show what's linked.  "
-                   "Link — create missing junctions.  "
-                   "Unlink — remove junctions (mod files are NOT deleted).")
+        desc_lbl = _desc(tab, row=0, text=t("tools.lm_desc"))
+        self._translatable.append((desc_lbl, "tools.lm_desc"))
 
-        # Command selector
-        cf = _row(tab, row=1, label="Command:")
+        # Command selector — values kept in English (drive internal logic)
+        cf, cmd_lbl = _row(tab, row=1, label=t("tools.label_command"))
+        self._translatable.append((cmd_lbl, "tools.label_command"))
         self._lm_cmd_var = ctk.StringVar(value="Status")
         ctk.CTkSegmentedButton(
             cf,
@@ -231,33 +250,36 @@ class ToolsView(BaseView):
         ).pack(side="left")
 
         # Group (required — no "All groups")
-        gf = _row(tab, row=2, label="Group:")
+        gf, group_lbl = _row(tab, row=2, label=t("tools.label_group"))
+        self._translatable.append((group_lbl, "tools.label_group"))
         self._lm_group_var = ctk.StringVar(value="")
         self._lm_group_menu = ctk.CTkOptionMenu(
             gf, variable=self._lm_group_var,
-            values=["(no groups found)"], width=200,
+            values=[t("tools.no_groups")], width=200,
             command=lambda _: self._lm_on_change(),
         )
         self._lm_group_menu.pack(side="left")
 
         # Warning (shown for Unlink)
-        self._lm_warn = ctk.CTkLabel(
-            tab,
-            text="⚠  Unlink removes junction links from the Arma 3 directory. "
-                 "Mod files in downloads/ are NOT deleted.",
-            text_color=_WARN_COLOR, anchor="w",
-        )
+        self._lm_warn = ctk.CTkLabel(tab, text=t("tools.lm_warn"),
+                                     text_color=_WARN_COLOR, anchor="w")
+        self._translatable.append((self._lm_warn, "tools.lm_warn"))
 
         # Run button (label changes with command)
         self._lm_run_btn = ctk.CTkButton(
-            tab, text="Show Status", width=180,
+            tab, text=t("tools.lm_show_status"), width=180,
             command=self._lm_run,
         )
         self._lm_run_btn.grid(row=10, column=0, padx=24, pady=(16, 24), sticky="e")
 
     def _lm_on_change(self, _: str = "") -> None:
         cmd = self._lm_cmd_var.get()
-        labels = {"Status": "Show Status", "Link": "Create Links", "Unlink": "Remove Links"}
+        # Keys are English segmented-button values; values are translated labels
+        labels = {
+            "Status": t("tools.lm_show_status"),
+            "Link":   t("tools.lm_create_links"),
+            "Unlink": t("tools.lm_remove_links"),
+        }
         self._lm_run_btn.configure(text=labels.get(cmd, cmd))
 
         if cmd == "Unlink":
@@ -269,19 +291,17 @@ class ToolsView(BaseView):
         cmd   = self._lm_cmd_var.get().lower()
         group = self._lm_group_var.get()
 
-        if not group or group == "(no groups found)":
-            messagebox.showwarning("No group selected",
-                                   "Please select a group from the dropdown.")
+        if not group or group == t("tools.no_groups"):
+            messagebox.showwarning(t("tools.lm_no_group_title"),
+                                   t("tools.lm_no_group_body"))
             return
 
         args = ["link_mods.py", cmd, "--group", group]
 
         if cmd == "unlink":
             confirmed = messagebox.askyesno(
-                "Confirm Unlink",
-                f"Remove junction links for group '{group}'?\n\n"
-                "This removes links from the Arma 3 directory but does NOT delete "
-                "mod files in downloads/.",
+                t("tools.lm_confirm_title"),
+                t("tools.lm_confirm_body", group=group),
             )
             if not confirmed:
                 return
@@ -296,17 +316,16 @@ class ToolsView(BaseView):
         tab = self._tab_view.tab("Sync Missing")
         tab.grid_columnconfigure(0, weight=1)
 
-        _desc(tab, row=0,
-              text="Retry downloading mods that were missing from the server "
-                   "when you last ran the pipeline. "
-                   "Checks the server again and downloads any that have since appeared.")
+        desc_lbl = _desc(tab, row=0, text=t("tools.sm_desc"))
+        self._translatable.append((desc_lbl, "tools.sm_desc"))
 
         self._sm_info = ctk.CTkLabel(tab, text="", text_color="gray", anchor="w")
         self._sm_info.grid(row=1, column=0, padx=24, pady=(4, 0), sticky="w")
 
-        ctk.CTkButton(tab, text="Run Sync Missing", width=180,
-                      command=lambda: self._launch(["sync_missing.py"])).grid(
-            row=10, column=0, padx=24, pady=(16, 24), sticky="e")
+        sm_btn = ctk.CTkButton(tab, text=t("tools.sm_btn"), width=180,
+                               command=lambda: self._launch(["sync_missing.py"]))
+        sm_btn.grid(row=10, column=0, padx=24, pady=(16, 24), sticky="e")
+        self._translatable.append((sm_btn, "tools.sm_btn"))
 
     def _update_sm_label(self) -> None:
         cfg = self.app.cfg
@@ -321,13 +340,11 @@ class ToolsView(BaseView):
             try:
                 data  = json.loads(report_path.read_text(encoding="utf-8"))
                 count = data.get("missing", len(data.get("missing_mods", [])))
-                self._sm_info.configure(
-                    text=f"{count} mod(s) currently listed as missing.")
+                self._sm_info.configure(text=t("tools.sm_count", count=count))
                 return
             except Exception:
                 pass
-        self._sm_info.configure(
-            text="No missing_report.json found — run the pipeline first.")
+        self._sm_info.configure(text=t("tools.sm_no_report"))
 
     # -------------------------------------------------------------------------
 
@@ -336,17 +353,16 @@ class ToolsView(BaseView):
         tab = self._tab_view.tab("Report Missing")
         tab.grid_columnconfigure(0, weight=1)
 
-        _desc(tab, row=0,
-              text="Check which mods from comparison.json are absent from the "
-                   "file server. Saves missing_report.json so you can track what "
-                   "still needs to be added to the server.")
+        desc_lbl = _desc(tab, row=0, text=t("tools.rm_desc"))
+        self._translatable.append((desc_lbl, "tools.rm_desc"))
 
         self._rm_info = ctk.CTkLabel(tab, text="", text_color="gray", anchor="w")
         self._rm_info.grid(row=1, column=0, padx=24, pady=(4, 0), sticky="w")
 
-        ctk.CTkButton(tab, text="Generate Report", width=180,
-                      command=lambda: self._launch(["report_missing.py"])).grid(
-            row=10, column=0, padx=24, pady=(16, 24), sticky="e")
+        rm_btn = ctk.CTkButton(tab, text=t("tools.rm_btn"), width=180,
+                               command=lambda: self._launch(["report_missing.py"]))
+        rm_btn.grid(row=10, column=0, padx=24, pady=(16, 24), sticky="e")
+        self._translatable.append((rm_btn, "tools.rm_btn"))
 
     def _update_rm_label(self) -> None:
         cfg = self.app.cfg
@@ -361,11 +377,213 @@ class ToolsView(BaseView):
             try:
                 data = json.loads(report_path.read_text(encoding="utf-8"))
                 ts   = data.get("generated_at", "unknown")
-                self._rm_info.configure(text=f"Last generated: {ts}")
+                self._rm_info.configure(text=t("tools.rm_last", ts=ts))
                 return
             except Exception:
                 pass
-        self._rm_info.configure(text="No report yet.")
+        self._rm_info.configure(text=t("tools.rm_none"))
+
+    # -------------------------------------------------------------------------
+
+    def _build_clean_orphans_tab(self) -> None:
+        self._tab_view.add("Clean Orphans")
+        tab = self._tab_view.tab("Clean Orphans")
+        tab.grid_columnconfigure(0, weight=1)
+        tab.grid_rowconfigure(3, weight=1)
+
+        desc_lbl = _desc(tab, row=0, text=t("tools.oc_desc"))
+        self._translatable.append((desc_lbl, "tools.oc_desc"))
+
+        oc_warn = ctk.CTkLabel(tab, text=t("tools.oc_warn"),
+                               text_color=_WARN_COLOR, anchor="w")
+        oc_warn.grid(row=1, column=0, padx=24, pady=(0, 4), sticky="w")
+        self._translatable.append((oc_warn, "tools.oc_warn"))
+
+        self._oc_status = ctk.CTkLabel(tab, text="", text_color="gray", anchor="w")
+        self._oc_status.grid(row=2, column=0, padx=24, pady=(0, 2), sticky="w")
+
+        # Scrollable list for results
+        self._oc_scroll = ctk.CTkScrollableFrame(tab)
+        self._oc_scroll.grid(row=3, column=0, sticky="nsew", padx=16, pady=(0, 4))
+        self._oc_scroll.grid_columnconfigure(0, weight=1)
+
+        # Bottom action bar
+        bot = ctk.CTkFrame(tab, fg_color="transparent")
+        bot.grid(row=4, column=0, sticky="ew", padx=16, pady=(4, 12))
+
+        self._oc_sel_all_btn = ctk.CTkButton(
+            bot, text=t("tools.oc_sel_all"), width=110,
+            command=self._oc_select_all,
+        )
+        self._oc_sel_all_btn.pack(side="left", padx=(0, 4))
+        self._translatable.append((self._oc_sel_all_btn, "tools.oc_sel_all"))
+
+        self._oc_sel_none_btn = ctk.CTkButton(
+            bot, text=t("tools.oc_sel_none"), width=110,
+            command=self._oc_deselect_all,
+        )
+        self._oc_sel_none_btn.pack(side="left", padx=4)
+        self._translatable.append((self._oc_sel_none_btn, "tools.oc_sel_none"))
+
+        self._oc_scan_btn = ctk.CTkButton(
+            bot, text=t("tools.oc_scan_btn"), width=150,
+            command=self._oc_scan,
+        )
+        self._oc_scan_btn.pack(side="right", padx=(4, 0))
+        self._translatable.append((self._oc_scan_btn, "tools.oc_scan_btn"))
+
+        self._oc_delete_btn = ctk.CTkButton(
+            bot, text=t("tools.oc_delete_btn"), width=150,
+            fg_color="darkred", hover_color="#8b0000",
+            command=self._oc_delete_selected,
+            state="disabled",
+        )
+        self._oc_delete_btn.pack(side="right", padx=4)
+        self._translatable.append((self._oc_delete_btn, "tools.oc_delete_btn"))
+
+        # Internal scan state
+        self._oc_orphans: list[dict] = []
+        self._oc_check_vars: list[ctk.BooleanVar] = []
+        self._oc_pending_done_msg: str | None = None
+
+    def _oc_scan(self) -> None:
+        cfg = self.app.cfg
+        if not cfg:
+            self._oc_status.configure(text=t("tools.oc_no_config"), text_color="gray")
+            return
+        if not cfg.comparison.exists():
+            self._oc_status.configure(text=t("tools.oc_no_comparison"), text_color="gray")
+            return
+
+        self._oc_scan_btn.configure(state="disabled", text=t("tools.oc_scanning"))
+        self._oc_delete_btn.configure(state="disabled")
+        self._oc_status.configure(text=t("tools.oc_scanning"), text_color="gray")
+
+        def _run() -> None:
+            try:
+                comparison = json.loads(cfg.comparison.read_text(encoding="utf-8"))
+                orphans = find_orphan_folders(cfg.downloads, comparison)
+            except Exception as e:
+                self.after(0, lambda: self._oc_scan_done(None, str(e)))
+                return
+            self.after(0, lambda: self._oc_scan_done(orphans, None))
+
+        threading.Thread(target=_run, daemon=True).start()
+
+    def _oc_scan_done(self, orphans: list[dict] | None, error: str | None) -> None:
+        self._oc_scan_btn.configure(state="normal", text=t("tools.oc_scan_btn"))
+
+        # Consume any pending success message from a previous delete operation
+        done_msg = self._oc_pending_done_msg
+        self._oc_pending_done_msg = None
+
+        # Clear previous results
+        for w in self._oc_scroll.winfo_children():
+            w.destroy()
+        self._oc_orphans = []
+        self._oc_check_vars = []
+
+        if error:
+            self._oc_status.configure(text=t("tools.oc_scan_error", e=error), text_color="red")
+            return
+
+        if not orphans:
+            msg = done_msg or t("tools.oc_none_found")
+            self._oc_status.configure(text=msg, text_color="gray")
+            return
+
+        total_size = sum(o["size"] for o in orphans)
+        self._oc_status.configure(
+            text=t("tools.oc_found", count=len(orphans), size=_fmt_size(total_size)),
+            text_color="gray",
+        )
+        self._oc_orphans = orphans
+        self._oc_delete_btn.configure(state="normal")
+
+        for i, orphan in enumerate(orphans):
+            var = ctk.BooleanVar(value=True)
+            self._oc_check_vars.append(var)
+            bg = ("gray90", "gray17") if i % 2 == 0 else ("gray86", "gray14")
+            row = ctk.CTkFrame(self._oc_scroll, fg_color=bg, corner_radius=4)
+            row.pack(fill="x", pady=1)
+            row.columnconfigure(1, weight=1)
+
+            ctk.CTkCheckBox(row, text="", variable=var, width=24).grid(
+                row=0, column=0, padx=(8, 4), pady=4,
+            )
+            ctk.CTkLabel(
+                row,
+                text=f"  {orphan['group']} / {orphan['name']}",
+                anchor="w",
+            ).grid(row=0, column=1, sticky="ew", padx=4)
+            ctk.CTkLabel(
+                row,
+                text=_fmt_size(orphan["size"]),
+                text_color="gray",
+                width=80,
+                anchor="e",
+            ).grid(row=0, column=2, padx=(4, 12))
+
+    def _oc_select_all(self) -> None:
+        for var in self._oc_check_vars:
+            var.set(True)
+
+    def _oc_deselect_all(self) -> None:
+        for var in self._oc_check_vars:
+            var.set(False)
+
+    def _oc_delete_selected(self) -> None:
+        selected = [
+            self._oc_orphans[i]
+            for i, var in enumerate(self._oc_check_vars)
+            if var.get()
+        ]
+        if not selected:
+            return
+        total_size = sum(o["size"] for o in selected)
+        confirmed = messagebox.askyesno(
+            t("tools.oc_confirm_title"),
+            t("tools.oc_confirm_body", count=len(selected), size=_fmt_size(total_size)),
+        )
+        if not confirmed:
+            return
+
+        self._oc_delete_btn.configure(state="disabled")
+        self._oc_scan_btn.configure(state="disabled")
+
+        def _run() -> None:
+            freed = 0
+            errors = []
+            for orphan in selected:
+                try:
+                    p = orphan["path"]
+                    if _is_junction(p):
+                        # Safety: never rmtree a junction — it follows the
+                        # reparse point and deletes the target's contents.
+                        # Use remove_junction() which calls os.rmdir() instead.
+                        ok, err = remove_junction(p)
+                        if not ok:
+                            errors.append(t("tools.oc_error", path=p.name, e=err))
+                            continue
+                    else:
+                        shutil.rmtree(p)
+                    freed += orphan["size"]
+                except Exception as e:
+                    errors.append(t("tools.oc_error", path=orphan["path"].name, e=e))
+            self.after(0, lambda: self._oc_delete_done(len(selected), freed, errors))
+
+        threading.Thread(target=_run, daemon=True).start()
+
+    def _oc_delete_done(self, count: int, freed: int, errors: list[str]) -> None:
+        # Store success message so _oc_scan_done() can display it after the rescan
+        self._oc_pending_done_msg = (
+            None if errors
+            else t("tools.oc_done", count=count, size=_fmt_size(freed))
+        )
+        self._oc_scan_btn.configure(state="normal")
+        self._oc_scan()
+        if errors:
+            messagebox.showerror(t("tools.oc_error_title"), "\n".join(errors))
 
     # =========================================================================
     # Private — helpers
@@ -389,6 +607,21 @@ class ToolsView(BaseView):
         self.app.run_tool(args)
 
 
+# ---------------------------------------------------------------------------
+# Size formatting helper
+# ---------------------------------------------------------------------------
+
+def _fmt_size(n: int) -> str:
+    """Human-readable file size string."""
+    if n < 1024:
+        return f"{n} B"
+    if n < 1024 ** 2:
+        return f"{n / 1024:.1f} KB"
+    if n < 1024 ** 3:
+        return f"{n / 1024 ** 2:.1f} MB"
+    return f"{n / 1024 ** 3:.2f} GB"
+
+
 # ---------------------------------------------------------------------------
 # Layout helpers
 # ---------------------------------------------------------------------------
@@ -400,10 +633,14 @@ def _desc(parent, row: int, text: str) -> ctk.CTkLabel:
     return lbl
 
 
-def _row(parent, row: int, label: str) -> ctk.CTkFrame:
-    """A label + horizontal frame for a settings row."""
-    ctk.CTkLabel(parent, text=label, anchor="w", width=110).grid(
-        row=row, column=0, padx=(24, 0), pady=6, sticky="w")
+def _row(parent, row: int, label: str) -> tuple[ctk.CTkFrame, ctk.CTkLabel]:
+    """A label + horizontal frame for a settings row.
+
+    Returns (content_frame, label_widget) so callers can register the label
+    for later retranslation.
+    """
+    lbl = ctk.CTkLabel(parent, text=label, anchor="w", width=110)
+    lbl.grid(row=row, column=0, padx=(24, 0), pady=6, sticky="w")
     f = ctk.CTkFrame(parent, fg_color="transparent")
     f.grid(row=row, column=0, padx=(140, 24), pady=6, sticky="w")
-    return f
+    return f, lbl

gui/wizard.py

@@ -1,12 +1,14 @@
 from __future__ import annotations
 
 import json
+import threading
+from tkinter import TclError, filedialog
 from typing import Callable
 
 import customtkinter as ctk
-from tkinter import filedialog
 
 from gui._constants import COLOR_OK, COLOR_ERROR, PROJECT_ROOT
+from gui.locales import t
 
 
 class SetupWizard(ctk.CTkToplevel):
@@ -18,7 +20,7 @@ class SetupWizard(ctk.CTkToplevel):
         on_complete: Callable[[], None],
     ) -> None:
         super().__init__(parent)
-        self.title("Setup — Arma Mod Manager")
+        self.title(t("wizard.title"))
         self.geometry("500x420")
         self.resizable(False, False)
         self.grab_set()
@@ -48,20 +50,20 @@ class SetupWizard(ctk.CTkToplevel):
 
     def _page_server(self) -> None:
         ctk.CTkLabel(
-            self._body, text="Step 1 of 3 — Server Connection",
+            self._body, text=t("wizard.step1_title"),
             font=ctk.CTkFont(size=16, weight="bold"),
         ).pack(anchor="w")
         ctk.CTkLabel(
-            self._body, text="Enter the details for your Caddy mod server.",
+            self._body, text=t("wizard.step1_desc"),
             text_color="gray",
         ).pack(anchor="w", pady=(4, 18))
 
-        for lbl, var, show in [
-            ("Server URL", self._url,  ""),
-            ("Username",   self._user, ""),
-            ("Password",   self._pw,   "•"),
+        for lbl_key, var, show in [
+            ("wizard.label_url",  self._url,  ""),
+            ("wizard.label_user", self._user, ""),
+            ("wizard.label_pw",   self._pw,   "•"),
         ]:
-            ctk.CTkLabel(self._body, text=lbl).pack(anchor="w")
+            ctk.CTkLabel(self._body, text=t(lbl_key)).pack(anchor="w")
             ctk.CTkEntry(self._body, textvariable=var, width=440, show=show).pack(
                 anchor="w", pady=(2, 10))
 
@@ -69,69 +71,85 @@ class SetupWizard(ctk.CTkToplevel):
         foot.pack(fill="x", pady=(8, 0))
         self._conn_lbl = ctk.CTkLabel(foot, text="", text_color="gray")
         self._conn_lbl.pack(side="left")
-        ctk.CTkButton(foot, text="Next →", width=90,
+        ctk.CTkButton(foot, text=t("wizard.btn_next"), width=90,
                       command=lambda: self._show(1)).pack(side="right")
-        ctk.CTkButton(foot, text="Test Connection", width=140,
+        self._test_btn = ctk.CTkButton(foot, text=t("wizard.btn_test"), width=140,
                       fg_color="transparent", border_width=1,
                       text_color=("gray10", "gray90"),
-                      command=self._test).pack(side="right", padx=(0, 8))
+                      command=self._test)
+        self._test_btn.pack(side="right", padx=(0, 8))
 
     def _test(self) -> None:
-        self._conn_lbl.configure(text="Testing…", text_color="gray")
-        self.update()
+        # Capture widget refs now — _clear() replaces them if the user
+        # navigates away and back while the request is in-flight.
+        lbl = self._conn_lbl
+        btn = self._test_btn
+        lbl.configure(text=t("wizard.testing"), text_color="gray")
+        btn.configure(state="disabled")
+
+        url  = self._url.get()
+        auth = (self._user.get(), self._pw.get())
+
+        def worker() -> None:
             try:
                 import requests
-            r = requests.get(self._url.get(),
-                             auth=(self._user.get(), self._pw.get()),
-                             timeout=8)
+                r = requests.get(url, auth=auth, timeout=8)
                 if r.ok:
-                self._conn_lbl.configure(text="✓ Connected", text_color=COLOR_OK)
+                    result = (t("wizard.connected"), COLOR_OK)
                 else:
-                self._conn_lbl.configure(text=f"✗ HTTP {r.status_code}",
-                                         text_color=COLOR_ERROR)
+                    result = (t("wizard.http_error", code=r.status_code), COLOR_ERROR)
             except Exception as e:
-            self._conn_lbl.configure(text=f"✗ {e}", text_color=COLOR_ERROR)
+                result = (t("wizard.conn_error", e=e), COLOR_ERROR)
+            self.after(0, lambda: _apply_test_result(lbl, btn, *result))
+
+        threading.Thread(target=worker, daemon=True).start()
+
+
+def _apply_test_result(lbl: ctk.CTkLabel, btn: ctk.CTkButton,
+                       text: str, color: str) -> None:
+    """Update connection test result widgets. Silently ignores destroyed widgets."""
+    try:
+        lbl.configure(text=text, text_color=color)
+        btn.configure(state="normal")
+    except TclError:
+        pass  # wizard was closed before the HTTP response arrived
 
     # ── Page 2: paths ────────────────────────────────────────────────────────
 
     def _page_paths(self) -> None:
         ctk.CTkLabel(
-            self._body, text="Step 2 of 3 — Arma 3 Server Folder",
+            self._body, text=t("wizard.step2_title"),
             font=ctk.CTkFont(size=16, weight="bold"),
         ).pack(anchor="w")
         ctk.CTkLabel(
-            self._body,
-            text="Point to your Arma 3 Server installation. "
-                 "Links (junctions) will be created here.",
+            self._body, text=t("wizard.step2_desc"),
             text_color="gray", wraplength=440, justify="left",
         ).pack(anchor="w", pady=(4, 18))
 
-        ctk.CTkLabel(self._body, text="Arma 3 Server folder").pack(anchor="w")
+        ctk.CTkLabel(self._body, text=t("wizard.label_arma")).pack(anchor="w")
         row = ctk.CTkFrame(self._body, fg_color="transparent")
         row.pack(fill="x", pady=(2, 8))
         ctk.CTkEntry(row, textvariable=self._arma, width=350).pack(side="left")
-        ctk.CTkButton(row, text="Browse", width=80,
+        ctk.CTkButton(row, text=t("wizard.btn_browse"), width=80,
                       command=self._browse_arma).pack(side="left", padx=8)
 
         ctk.CTkLabel(
-            self._body,
-            text="All other folders (downloads, presets) will be created "
-                 "automatically next to this tool.",
+            self._body, text=t("wizard.step2_hint"),
             text_color="gray", font=ctk.CTkFont(size=11),
             wraplength=440, justify="left",
         ).pack(anchor="w", pady=(8, 0))
 
         foot = ctk.CTkFrame(self._body, fg_color="transparent")
         foot.pack(fill="x", pady=(20, 0))
-        ctk.CTkButton(foot, text="← Back", width=80,
+        ctk.CTkButton(foot, text=t("wizard.btn_back"), width=80,
                       fg_color="transparent", border_width=1,
                       text_color=("gray10", "gray90"),
                       command=lambda: self._show(0)).pack(side="left")
-        ctk.CTkButton(foot, text="Next →", width=80,
+        ctk.CTkButton(foot, text=t("wizard.btn_next"), width=80,
                       command=lambda: self._show(2)).pack(side="right")
 
     def _browse_arma(self) -> None:
-        d = filedialog.askdirectory(title="Select Arma 3 Server folder")
+        d = filedialog.askdirectory(title=t("wizard.browse_title"))
         if d:
             self._arma.set(d)
 
@@ -139,18 +157,18 @@ class SetupWizard(ctk.CTkToplevel):
 
     def _page_review(self) -> None:
         ctk.CTkLabel(
-            self._body, text="Step 3 of 3 — Review & Save",
+            self._body, text=t("wizard.step3_title"),
             font=ctk.CTkFont(size=16, weight="bold"),
         ).pack(anchor="w")
         ctk.CTkLabel(
-            self._body, text="Check your settings, then click Save.",
+            self._body, text=t("wizard.step3_desc"),
             text_color="gray",
         ).pack(anchor="w", pady=(4, 14))
 
         summary = (
             f"Server URL:   {self._url.get()}\n"
             f"Username:     {self._user.get()}\n"
-            f"Arma folder:  {self._arma.get() or '(not set)'}\n"
+            f"Arma folder:  {self._arma.get() or t('wizard.not_set')}\n"
         )
         box = ctk.CTkTextbox(self._body, height=90,
                              font=ctk.CTkFont(family="Consolas", size=12))
@@ -160,11 +178,11 @@ class SetupWizard(ctk.CTkToplevel):
 
         foot = ctk.CTkFrame(self._body, fg_color="transparent")
         foot.pack(fill="x")
-        ctk.CTkButton(foot, text="← Back", width=80,
+        ctk.CTkButton(foot, text=t("wizard.btn_back"), width=80,
                       fg_color="transparent", border_width=1,
                       text_color=("gray10", "gray90"),
                       command=lambda: self._show(1)).pack(side="left")
-        ctk.CTkButton(foot, text="Save & Open", width=120,
+        ctk.CTkButton(foot, text=t("wizard.btn_save"), width=120,
                       command=self._save).pack(side="right")
 
     def _save(self) -> None:

run.py

@@ -78,6 +78,22 @@ def step_compare(cfg) -> None:
     print(f"  -> {cfg.comparison}")
 
 
+def step_migrate(cfg) -> None:
+    if not cfg.comparison.exists():
+        print(f"  NOTE: {cfg.comparison} not found — skipping migration.")
+        return
+    if not cfg.downloads.is_dir():
+        print(f"  NOTE: downloads dir missing ({cfg.downloads}) — nothing to migrate.")
+        return
+    from arma_modlist_tools.migrator import migrate_mod_groups
+    comparison = json.loads(cfg.comparison.read_text(encoding="utf-8"))
+    arma_dir   = cfg.arma_dir if cfg.arma_dir.is_dir() else None
+    result     = migrate_mod_groups(cfg.downloads, arma_dir, comparison)
+    if result["errors"]:
+        for name, err in result["errors"].items():
+            print(f"  ERROR  {name}: {err}")
+
+
 def step_fetch(cfg) -> None:
     if not cfg.comparison.exists():
         print(f"  ERROR: {cfg.comparison} not found. Run parse + compare first.")
@@ -91,9 +107,14 @@ def step_fetch(cfg) -> None:
         for mod in data["mods"]:
             queue.append((mod, preset_name))
 
+    def _index_progress(current: int, total: int, name: str) -> None:
+        if current == 1 or current % 25 == 0 or current == total:
+            print(f"  Indexing {current}/{total}: {name}")
+
     print(f"  Building server index...")
-    index = build_server_index(cfg.server_url, cfg.server_auth)
-    print(f"  Indexed {len(index['by_steam_id'])} mods\n")
+    index = build_server_index(cfg.server_url, cfg.server_auth, progress_fn=_index_progress)
+    print(f"  Indexed {len(index['by_steam_id'])} mods by steam_id, "
+          f"{len(index['by_name'])} by name\n")
 
     session  = make_session(cfg.server_auth)
     resolved = []
@@ -173,6 +194,7 @@ def main() -> None:
     parser = argparse.ArgumentParser(description="Run the full mod management pipeline.")
     parser.add_argument("--skip-parse",   action="store_true")
     parser.add_argument("--skip-compare", action="store_true")
+    parser.add_argument("--skip-migrate", action="store_true")
     parser.add_argument("--skip-fetch",   action="store_true")
     parser.add_argument("--skip-link",    action="store_true")
     parser.add_argument("--group", "-g",  metavar="GROUP",
@@ -182,13 +204,15 @@ def main() -> None:
     steps = [
         (not args.skip_parse,   "Parse presets"),
         (not args.skip_compare, "Compare presets"),
+        (not args.skip_migrate, "Migrate mods"),
         (not args.skip_fetch,   "Fetch mods"),
         (not args.skip_link,    "Link mods"),
     ]
     active_count = sum(1 for run, _ in steps if run)
     step_num = 0
 
-    if args.skip_parse and args.skip_compare and args.skip_fetch and args.skip_link:
+    if (args.skip_parse and args.skip_compare and args.skip_migrate
+            and args.skip_fetch and args.skip_link):
         print("All steps skipped — nothing to do.")
         sys.exit(0)
 
@@ -196,6 +220,7 @@ def main() -> None:
         (cfg,),
         (cfg,),
         (cfg,),
+        (cfg,),
         None,  # handled separately
     ]):
         if not run:
@@ -216,6 +241,8 @@ def main() -> None:
             step_parse(cfg)
         elif name == "Compare presets":
             step_compare(cfg)
+        elif name == "Migrate mods":
+            step_migrate(cfg)
         elif name == "Fetch mods":
             step_fetch(cfg)
 

update_mods.py

@@ -102,6 +102,7 @@ def main() -> None:
     COL_GROUP = 24
 
     total_checked = total_updated = total_bytes = 0
+    total_removed = 0
     not_on_server = []
 
     for group, folder_name, mod_dir in targets:
@@ -123,13 +124,21 @@ def main() -> None:
         all_files = list_mod_files(folder_url, session) if not args.force else stale
         checked = len(all_files) if not args.force else len(stale)
 
-        if not stale:
+        # Find local files that no longer exist on the server (orphans)
+        server_rel = {rel for rel, _, _ in all_files}
+        orphans = [
+            f for f in mod_dir.rglob("*") if f.is_file()
+            and str(f.relative_to(mod_dir)).replace("\\", "/") not in server_rel
+        ]
+
+        if not stale and not orphans:
             print(f"  [=] {folder_name:<{COL_MOD}}  {group:<{COL_GROUP}}  {checked} files  up-to-date")
             total_checked += checked
             continue
 
         # Download stale files
         mod_bytes = 0
+        if stale:
             with tqdm(
                 total=len(stale), unit="file",
                 desc=f"  {folder_name[-COL_MOD:]:<{COL_MOD}}",
@@ -148,21 +157,32 @@ def main() -> None:
                     mod_bytes += n
                     file_bar.update(1)
 
+        # Remove orphan files
+        for orphan in orphans:
+            tqdm.write(f"  [-] orphan removed: {orphan.relative_to(mod_dir)}")
+            orphan.unlink()
+
         total_checked += checked
         total_updated += len(stale)
         total_bytes   += mod_bytes
-        print(f"  [+] {folder_name:<{COL_MOD}}  {group:<{COL_GROUP}}  "
-              f"{checked} files  {len(stale)} updated  ({_fmt_bytes(mod_bytes)})")
+        total_removed += len(orphans)
+        parts = [f"{checked} files"]
+        if stale:
+            parts.append(f"{len(stale)} updated ({_fmt_bytes(mod_bytes)})")
+        if orphans:
+            parts.append(f"{len(orphans)} orphan(s) removed")
+        print(f"  [+] {folder_name:<{COL_MOD}}  {group:<{COL_GROUP}}  {'  '.join(parts)}")
 
     print(f"\n{'='*56}")
     print(f"  Total: {total_checked} files checked, "
           f"{total_updated} updated, "
+          f"{total_removed} orphan(s) removed, "
           f"{_fmt_bytes(total_bytes)} downloaded")
     if not_on_server:
         print(f"  Not found on server ({len(not_on_server)}): {', '.join(not_on_server)}")
     print(f"{'='*56}\n")
 
-    if total_updated == 0 and not not_on_server:
+    if total_updated == 0 and total_removed == 0 and not not_on_server:
         print("  All mods are up-to-date.\n")