Port PSN pkg decryption to pure Python (drop Wine requirement)

app/nopaystation.py

@@ -2,9 +2,9 @@
 
 NoPayStation publishes per-platform TSV lists (``https://nopaystation.com/tsv/``)
 with one row per downloadable PSN item. Each row links to an encrypted PSN
-``.pkg`` (a ``\\x7FPKG`` container, not a ZIP) that must be decrypted with the
-``pkg2zip`` tool before it can be installed as a ``PSP/GAME/<TITLE_ID>/``
-folder.
+``.pkg`` (a ``\\x7FPKG`` container, not a ZIP) that is decrypted by the bundled
+pure-Python decryptor (``app/pkg.py``) into a ``PSP/GAME/<TITLE_ID>/``-style
+folder — no Wine or ``pkg2zip`` required.
 """
 from __future__ import annotations
 
@@ -173,22 +173,55 @@ def _safe_folder(value: str) -> str:
     return cleaned or "PKG"
 
 
-def extract_pkg(pkg_path, title_id: str, dest_dir, pkg2zip: Path,
-                progress_cb=None, cancel_event=None) -> Path:
-    """Decrypt/extract a ``.pkg`` with pkg2zip into ``dest_dir/<TITLE_ID>/``.
+def _ensure_keys_bin(folder, kind):
+    """PS1 Classics need KEYS.BIN next to EBOOT.PBP to boot on CFW (npdrm)."""
+    if kind != "psx":
+        return
+    src = config.DATA_DIR / "loader" / "KEYS.BIN"
+    dest = Path(folder) / "KEYS.BIN"
+    if src.is_file() and not dest.exists():
+        try:
+            shutil.copy2(src, dest)
+        except OSError:
+            pass
 
-    pkg2zip extracts PSP/PSX content into a folder layout we then normalize:
-    the game's ``EBOOT.PBP`` (plus siblings) are copied into the destination
-    game folder. Returns the destination folder path.
+
+def extract_pkg(pkg_path, title_id: str, dest_dir, pkg2zip: Path = None,
+                progress_cb=None, cancel_event=None) -> Path:
+    """Decrypt/extract a ``.pkg`` into ``dest_dir/<TITLE_ID>/``.
+
+    Uses the bundled pure-Python decryptor (no Wine / pkg2zip needed); falls
+    back to pkg2zip only if that fails and a binary is available. Returns the
+    destination game folder path.
     """
+    from . import pkg as pkgmod
     from .store import TransferCancelled
 
     pkg_path = Path(pkg_path)
-    folder_name = _safe_folder(title_id)
-    dest = Path(dest_dir) / folder_name
+    dest = Path(dest_dir) / _safe_folder(title_id)
     if (dest / "EBOOT.PBP").exists():
         return dest
 
+    # 1. Pure-Python decryptor (primary).
+    try:
+        _kind, _tid, folder = pkgmod.extract(pkg_path, dest_dir, progress_cb, cancel_event)
+        _ensure_keys_bin(folder, _kind)
+        return folder
+    except TransferCancelled:
+        raise
+    except Exception as exc:  # noqa: BLE001
+        py_exc = exc
+        log.warning("python pkg decrypt failed (%s); trying pkg2zip fallback", exc)
+
+    # 2. pkg2zip fallback (needs a binary; usually Wine + the bundled .exe).
+    if pkg2zip is None:
+        pkg2zip = find_pkg2zip()
+    if pkg2zip is None:
+        raise RuntimeError(
+            f"could not decrypt {pkg_path.name} (no pkg2zip available): {py_exc}"
+        )
+
+    folder_name = _safe_folder(title_id)
     tmp = Path(dest_dir).with_name(".nps-tmp-" + folder_name)
     if tmp.exists():
         shutil.rmtree(tmp, ignore_errors=True)
@@ -197,7 +230,7 @@ def extract_pkg(pkg_path, title_id: str, dest_dir, pkg2zip: Path,
     if progress_cb is not None:
         progress_cb("Extracting", 0.0, "")
     try:
-        cmd = _pkg2zip_cmd(pkg2zip) + ["-x", str(pkg_path)]
+        cmd = _pkg2zip_cmd(Path(pkg2zip)) + ["-x", str(pkg_path)]
         env = dict(os.environ)
         env["WINEDEBUG"] = "-all"  # silence Wine's console chatter
         proc = subprocess.Popen(