From 47a78077b46004b510041f6ac87d8c02fba7eb51 Mon Sep 17 00:00:00 2001
From: Romain Thomas <me@romainthomas.fr>
Date: Sun, 26 Nov 2023 15:48:58 +0100
Subject: [PATCH] Add helpers for cross-compilation

---
 api/python/backend/config.py |  2 ++
 api/python/backend/setup.py  | 25 +++++++++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/api/python/backend/config.py b/api/python/backend/config.py
index f86b66da66..eafc7d475f 100644
--- a/api/python/backend/config.py
+++ b/api/python/backend/config.py
@@ -87,6 +87,8 @@ def cmake_dump(self) -> List[str]:
 class CrossCompilation(BaseModel):
     osx_arch: Optional[str]  = Field(None, alias="osx-arch")
     platform: Optional[str] = None
+    pyversion: Optional[str] = None
+    abi: Optional[str] = None
 
     def cmake_dump(self) -> List[str]:
         out: List[str] = []
diff --git a/api/python/backend/setup.py b/api/python/backend/setup.py
index ac4aa41ffd..649dfc189e 100644
--- a/api/python/backend/setup.py
+++ b/api/python/backend/setup.py
@@ -13,6 +13,8 @@
 
 DEFAULT_CONF = CWD / ".." / "config-default.toml"
 
+_WHEEL_TAG_COMPUTE_BEST = None
+
 @lru_cache(maxsize=1)
 def get_config():
     from config import Config
@@ -21,6 +23,24 @@ def get_config():
         return Config.from_file(config_path)
     return Config.from_file(DEFAULT_CONF.as_posix())
 
+
+def _compute_best(cls, *arg, **kwargs):
+    from scikit_build_core.builder.wheel_tag import WheelTag
+    best_tag = _WHEEL_TAG_COMPUTE_BEST(cls, *arg, **kwargs)
+    config = get_config()
+
+    pyvers = best_tag.pyvers
+    abis = best_tag.abis
+    archs = best_tag.archs
+
+    if version := config.cross_compilation.pyversion:
+        pyvers = [version]
+
+    if abi := config.cross_compilation.abi:
+        abis = [abi]
+
+    return WheelTag(pyvers, abis, archs)
+
 def _fix_env():
     config = get_config()
     if sys.platform.startswith("win"):
@@ -42,6 +62,11 @@ def _fix_env():
         os.environ["ARCHFLAGS"]= f"-arch {config.osx_arch}"
 
     if platform := config.cross_compilation.platform:
+        global _WHEEL_TAG_COMPUTE_BEST
+        from scikit_build_core.builder.wheel_tag import WheelTag
+        _WHEEL_TAG_COMPUTE_BEST = WheelTag.compute_best
+        WheelTag.compute_best = _compute_best
+
         os.environ["_PYTHON_HOST_PLATFORM"] = platform
 
         if os.name == 'nt' and platform == 'win32':