Files
arma-modlist-tools/arma_modlist_tools/migrator.py
Tran G. (Revernomad) Khoa 48637ffe90 feat: add migrate step to move mod folders between groups on preset change
Before step_fetch, scan all downloads/ subdirs and move any mod that
comparison.json now assigns to a different group. Matching uses steam_id
(via meta.cpp publishedid) first, normalized name as fallback.

Stale junctions in arma_dir are removed before the folder move so
step_link can re-create them pointing to the new location.

- New arma_modlist_tools/migrator.py: migrate_mod_groups()
- run.py: step_migrate(), --skip-migrate flag, wired into dispatch loop
- gui/app.py: step_migrate inserted as Step 3/5 between compare and fetch
- gui/locales.py: add step3/4/5 names (en + vi), renumber old 3->4, 4->5
- test_suite.py: 7 new migrator tests (158 total, 0 failed)
2026-04-14 15:08:40 +07:00

187 lines
6.8 KiB
Python

"""
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