Init

ptlinux/install_status.py

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+"""Read-only installation state used by the native launcher."""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+from enum import Enum
+import json
+from pathlib import Path
+
+from .paths import AppPaths
+
+
+REQUIRED_GAME_FILES = (
+	Path("Game.exe"),
+	Path("game.dll"),
+	Path("game.ini"),
+	Path("game/maps/WhisperingVale.rovug"),
+)
+
+
+class PrimaryAction(str, Enum):
+	"""Action presented by the launcher's large primary button."""
+
+	INSTALL = "INSTALL"
+	UPDATE = "UPDATE"
+	PLAY = "PLAY"
+
+
+@dataclass(frozen=True)
+class GameInstallationStatus:
+	"""Local game completeness and its relationship to the official depot."""
+
+	action: PrimaryAction
+	installed: bool
+	local_build: int | None
+	official_build: int | None
+	missing_files: tuple[Path, ...]
+
+
+def inspect_game_installation(
+	paths: AppPaths,
+	official_build: int | None = None,
+) -> GameInstallationStatus:
+	"""Select Install, Update, or Play without modifying the installation.
+
+	A completed native sync is the verified source for the local depot build.
+	When the official build cannot be checked, a complete local game remains
+	playable so temporary network failures do not lock users out.
+	"""
+
+	if official_build is not None and (
+		isinstance(official_build, bool)
+		or not isinstance(official_build, int)
+		or official_build < 0
+	):
+		raise ValueError("official build must be a non-negative integer")
+
+	missing_files = tuple(
+		relative
+		for relative in REQUIRED_GAME_FILES
+		if not (paths.source_game / relative).is_file()
+	)
+	installed = not missing_files
+	local_build = _read_verified_local_build(paths.native_depot_state)
+	if not installed:
+		action = PrimaryAction.INSTALL
+	elif official_build is not None and (
+		local_build is None or local_build < official_build
+	):
+		action = PrimaryAction.UPDATE
+	else:
+		action = PrimaryAction.PLAY
+	return GameInstallationStatus(
+		action=action,
+		installed=installed,
+		local_build=local_build,
+		official_build=official_build,
+		missing_files=missing_files,
+	)
+
+
+def _read_verified_local_build(path: Path) -> int | None:
+	try:
+		value = json.loads(path.read_text(encoding="utf-8"))
+	except (OSError, UnicodeError, json.JSONDecodeError):
+		return None
+	if not isinstance(value, dict) or value.get("dry_run") is not False:
+		return None
+	build = value.get("build")
+	if isinstance(build, bool) or not isinstance(build, int) or build < 0:
+		return None
+	return build