# cmake/toolchains/linux-to-win-msvc.cmake
# Linux host -> Windows MSVC-ABI cross toolchain using clang-cl + lld-link
# + xwin-supplied Win10 SDK/CRT. Driven by Ninja Multi-Config.

set(CMAKE_SYSTEM_NAME      Windows)
set(CMAKE_SYSTEM_PROCESSOR x86_64)

if(NOT DEFINED XWIN_DIR)
  if(DEFINED ENV{XWIN_DIR})
    set(XWIN_DIR "$ENV{XWIN_DIR}")
  else()
    set(XWIN_DIR "$ENV{HOME}/.xwin/splat")
  endif()
endif()
set(XWIN_DIR "${XWIN_DIR}" CACHE PATH "xwin splat root (contains crt/ and sdk/)")

if(NOT EXISTS "${XWIN_DIR}/crt/include")
  message(FATAL_ERROR "XWIN_DIR=${XWIN_DIR} missing crt/include - run xwin splat.")
endif()

set(CMAKE_C_COMPILER   clang-cl)
set(CMAKE_CXX_COMPILER clang-cl)
set(CMAKE_LINKER       lld-link)
set(CMAKE_RC_COMPILER  llvm-rc)
set(CMAKE_AR           llvm-lib)
set(CMAKE_MT           llvm-mt)

set(CMAKE_C_COMPILER_TARGET   x86_64-pc-windows-msvc)
set(CMAKE_CXX_COMPILER_TARGET x86_64-pc-windows-msvc)

set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)

# Force /MD (release CRT) for every config. xenia's CMakeLists.txt does a
# `string(REPLACE "/MDd" "/MD" ...)` on CMAKE_CXX_FLAGS_DEBUG, but with
# clang-cl, the runtime selection comes from CMAKE_MSVC_RUNTIME_LIBRARY
# (which expands to -MDd in dash form), so the substitution misses.
# Pinning the policy here avoids the need for non-redistributable debug
# CRT DLLs (MSVCP140D.dll etc) at runtime, which xwin doesn't ship.
cmake_policy(SET CMP0091 NEW)
set(CMAKE_MSVC_RUNTIME_LIBRARY "MultiThreadedDLL")

# xwin's default splat is a flat layout (crt/include, sdk/include/{ucrt,um,shared,...}),
# which clang-cl's /winsysroot does NOT understand. Use explicit -imsvc + -libpath:
# instead. Re-running `xwin splat --use-winsysroot-style` would also work but
# requires re-downloading ~600 MB.
# Use SHELL: prefix so CMake doesn't deduplicate repeated -imsvc tokens.
add_compile_options(
  "SHELL:-imsvc \"${XWIN_DIR}/crt/include\""
  "SHELL:-imsvc \"${XWIN_DIR}/sdk/include/ucrt\""
  "SHELL:-imsvc \"${XWIN_DIR}/sdk/include/um\""
  "SHELL:-imsvc \"${XWIN_DIR}/sdk/include/shared\""
  "SHELL:-imsvc \"${XWIN_DIR}/sdk/include/winrt\""
)
add_link_options(
  "/libpath:${XWIN_DIR}/crt/lib/x86_64"
  "/libpath:${XWIN_DIR}/sdk/lib/ucrt/x86_64"
  "/libpath:${XWIN_DIR}/sdk/lib/um/x86_64"
)
# xwin pulls the latest MSVC STL which now hard-asserts Clang >= 19. Our host
# has Clang 18, which works fine in practice — opt out of the version check.
# (See yvals_core.h STL1000 in $XWIN_DIR/crt/include.)
add_compile_definitions(_ALLOW_COMPILER_AND_STL_VERSION_MISMATCH)
# llvm-rc needs SDK headers explicitly + the resource file's own dir so the
# RC's relative ICON path (../../../assets/icon/icon.ico) resolves.
get_filename_component(_toolchain_dir "${CMAKE_CURRENT_LIST_FILE}" DIRECTORY)
get_filename_component(_xenia_root "${_toolchain_dir}/../.." ABSOLUTE)
set(CMAKE_RC_FLAGS_INIT
    "/I \"${XWIN_DIR}/sdk/include/um\" /I \"${XWIN_DIR}/sdk/include/shared\" /I \"${_xenia_root}/src/xenia/app\"")

# Quiet MSVC-STL false positives and xenia-specific warnings that clang-cl
# emits but cl.exe doesn't (treated as errors under /WX).
add_compile_options(
  -Wno-microsoft-include
  -Wno-unused-command-line-argument
  -Wno-ignored-pragma-intrinsic
  -Wno-nonportable-include-path
  -Wno-pragma-pack
  -Wno-tautological-pointer-compare
  -Wno-microsoft-cast
  -Wno-deprecated-declarations
  # These are silenced for native Linux Clang in CMakeLists.txt's else() branch,
  # but the if(MSVC) branch fires under clang-cl and skips them — so re-add.
  -Wno-switch
  -Wno-attributes
  -Wno-deprecated-register
  -Wno-deprecated-volatile
  -Wno-deprecated-enum-enum-conversion
  # cl.exe accepts __pragma(optimize("s",on)); clang-cl only knows the empty
  # argument form. xenia gates XE_MSVC_OPTIMIZE_SMALL on _MSC_VER so the
  # rejected pragma still emits from the clang-cl path. Treat as no-op.
  -Wno-ignored-pragmas
  # xenia decorates several `virtual` methods with XE_FORCEINLINE; clang-cl
  # then complains that the inline body isn't visible in includer TUs
  # (definitions live in command_processor.cc). cl.exe accepts this silently.
  -Wno-undefined-inline
  -Wno-sizeof-pointer-memaccess
  # `'ZM'` (PE magic, stored little-endian as "MZ" in the binary) — cl.exe
  # accepts the multi-char constant silently; clang-cl errors under /WX.
  -Wno-multichar
)
# _mm_cvtsi64x_si128 is an MSVC-only alias for the standard _mm_cvtsi64_si128.
# Used (gated on XE_PLATFORM_WIN32) in xenia/gpu/draw_util.cc.
add_compile_definitions(_mm_cvtsi64x_si128=_mm_cvtsi64_si128)

# Plumb FXC for tools/build/compile_shader_dxbc.py (wine fxc auto-prepend).
# Use real Win10 SDK fxc.exe 10.x (supports SM 5_1, produces vkd3d-proton-
# acceptable DXBC).
if(DEFINED ENV{FXC_PATH})
  set(ENV_FXC "$ENV{FXC_PATH}")
else()
  set(ENV_FXC "$ENV{HOME}/.local/share/xenia-cross/fxc/fxc.exe")
endif()
set(ENV{FXC_PATH} "${ENV_FXC}")

set(CMAKE_FIND_ROOT_PATH "${XWIN_DIR}")
set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)