Adding tag_classes to select versions

foreign_cc/extensions.bzl

@@ -2,7 +2,49 @@
 
 load("//foreign_cc:repositories.bzl", "rules_foreign_cc_dependencies")
 
-def _init(_):
-    rules_foreign_cc_dependencies(register_toolchains = False, register_preinstalled_tools = False, register_built_pkgconfig_toolchain = True)
+_DEFAULT_CMAKE_VERSION = "3.23.2"
+_DEFAULT_NINJA_VERSION = "1.11.1"
 
-tools = module_extension(implementation = _init)
+cmake_toolchain_version = tag_class(attrs = {
+    "version": attr.string(doc = "The cmake version", default = _DEFAULT_CMAKE_VERSION),
+})
+
+ninja_toolchain_version = tag_class(attrs = {
+    "version": attr.string(doc = "The ninja version", default = _DEFAULT_NINJA_VERSION),
+})
+
+def _init(module_ctx):
+    rules_foreign_cc_dependencies(
+        register_toolchains = False,
+        register_built_tools = False,
+        register_default_tools = False,
+        register_preinstalled_tools = False,
+        register_built_pkgconfig_toolchain = True,
+    )
+
+    versions = {
+        "cmake": "3.23.2",
+        "ninja": "1.11.1",
+    }
+
+    for mod in module_ctx.modules:
+        if not mod.is_root:
+            for toolchain in mod.tags.cmake:
+                versions["cmake"] = toolchain.version
+
+            for toolchain in mod.tags.ninja:
+                versions["ninja"] = toolchain.version
+
+    prebuilt_toolchains(
+        cmake_version = versions["cmake"],
+        ninja_version = versions["ninja"],
+        register_toolchains = False,
+    )
+
+tools = module_extension(
+    implementation = _init,
+    tag_classes = {
+        "cmake": cmake_toolchain_version,
+        "ninja": ninja_version,
+    },
+)