From f8887a4bafc3ae1f8d97a001eba1e8c0ed6e594c Mon Sep 17 00:00:00 2001
From: tretrauit <tretrauit@gmail.com>
Date: Sat, 17 Jun 2023 03:33:37 +0700
Subject: [PATCH] feat: implement get_version

Thanks An Anime Team for the code xD
---
 vollerei/hsr/launcher/game.py | 48 +++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/vollerei/hsr/launcher/game.py b/vollerei/hsr/launcher/game.py
index 14b0b9d..1c2d5cd 100644
--- a/vollerei/hsr/launcher/game.py
+++ b/vollerei/hsr/launcher/game.py
@@ -19,6 +19,9 @@ class Game(GameABC):
     def path(self) -> Path | None:
         return self._path
 
+    def data_folder(self) -> Path:
+        return self._path.joinpath("StarRail_Data")
+
     def is_installed(self) -> bool:
         if self._path is None:
             return False
@@ -28,6 +31,49 @@ class Game(GameABC):
         ):
             return False
 
+    def get_version(self) -> tuple[int, int, int]:
+        """
+        Get the current installed game version.
+
+        Credits to An Anime Team for the code that does the magic:
+        https://github.com/an-anime-team/anime-game-core/blob/main/src/games/star_rail/game.rs#L49
+        """
+        allowed = [48, 49, 50, 51, 52, 53, 54, 55, 56, 57]
+        version_bytes: list[bytes] = [0, 0, 0]
+        version_ptr = 0
+        correct = True
+        with self.data_folder().joinpath("data.unity3d").open("rb") as f:
+            f.seek(0x7D0)  # 2000 in decimal
+            for byte in f.read(10000):
+                match byte:
+                    case 0:
+                        version_bytes = [0, 0, 0]
+                        version_ptr = 0
+                        correct = True
+                    case 46:
+                        version_ptr += 1
+                        if version_ptr > 2:
+                            correct = False
+                    case 38:
+                        if (
+                            correct
+                            and version_bytes[0] > 0
+                            and version_bytes[1] > 0
+                            and version_bytes[2] > 0
+                        ):
+                            # TODO: The below code is not correct.
+                            return (
+                                int(version_bytes[0]),
+                                int(version_bytes[1]),
+                                int(version_bytes[2]),
+                            )
+                    case _:
+                        if correct and byte in allowed:
+                            version_bytes[version_ptr] += byte
+                        else:
+                            correct = False
+        return (0, 0, 0)
+
     def get_channel(self) -> GameChannel:
         if self.get_version() == (1, 0, 5):
             for channel, v in md5sums["1.0.5"].values():
@@ -42,3 +88,5 @@ class Game(GameABC):
                             return GameChannel.China
                         case "os":
                             return GameChannel.Overseas
+        else:
+            return