TERMUX_PKG_HOMEPAGE=https://github.com/kpet/clvk
TERMUX_PKG_DESCRIPTION="Experimental implementation of OpenCL on Vulkan"
TERMUX_PKG_LICENSE="Apache-2.0"
TERMUX_PKG_MAINTAINER="@termux"
_COMMIT=051e883725d957fa015a8a22fc6eb02936cd2d8b
_COMMIT_DATE=20221126
_COMMIT_TIME=072044
TERMUX_PKG_VERSION="0.0.20221126.072044g051e8837"
TERMUX_PKG_SRCURL=https://github.com/kpet/clvk.git
TERMUX_PKG_GIT_BRANCH=main
TERMUX_PKG_BUILD_DEPENDS="vulkan-headers, vulkan-loader-android"
TERMUX_PKG_DEPENDS="libc++"
TERMUX_PKG_SUGGESTS="ocl-icd"
TERMUX_PKG_HOSTBUILD=true
TERMUX_PKG_AUTO_UPDATE=true
TERMUX_PKG_EXTRA_CONFIGURE_ARGS="
-DLLVM_TABLEGEN=$TERMUX_PKG_HOSTBUILD_DIR/bin/llvm-tblgen
-DCLANG_TABLEGEN=$TERMUX_PKG_HOSTBUILD_DIR/bin/clang-tblgen
"

# https://github.com/kpet/clvk/blob/main/CMakeLists.txt

# clvk prefers Khronos Vulkan Loader instead of NDK stub
# Sticking with NDK should expose more Vulkan limitations in Android
# As noted in build test, failure comes when linking with API 24 libvulkan.so
# clvk will not work on Android versions older than Android 9 (API 28)
#
# [1877/1888] Linking CXX executable api_tests
# FAILED: api_tests
# ...
# libOpenCL.so: error: undefined reference to 'vkGetPhysicalDeviceFeatures2'
TERMUX_PKG_EXTRA_CONFIGURE_ARGS+="
-DCLVK_BUILD_TESTS=OFF
-DCLVK_VULKAN_IMPLEMENTATION=custom
-DVulkan_INCLUDE_DIRS=$TERMUX_PREFIX/include
-DVulkan_LIBRARIES=vulkan
"

# clvk libOpenCL.so has hardcoded clspv bin path at build time
# clvk cant automatically find clspv from PATH env var
# and rely on CLVK_CLSPV_BIN env var
# Use CLVK_CLSPV_ONLINE_COMPILER=ON to combine clspv with clvk
TERMUX_PKG_EXTRA_CONFIGURE_ARGS+=" -DCLVK_CLSPV_ONLINE_COMPILER=ON"

# clvk currently does not have proper versioning nor releases
# Use dates and commits as versioning for now
termux_pkg_auto_update() {
	local latest_commit_date_tz latest_commit_date latest_commit_time latest_version
	local latest_commit=$(curl -s https://api.github.com/repos/kpet/clvk/commits | jq .[].sha | head -1 | sed -e 's|\"||g')

	if [ -z "$latest_commit" ]; then
		echo "WARN: Unable to get latest commit from upstream. Try again later." >&2
		return 0
	fi

	if [ "$latest_commit" = "$_COMMIT" ]; then
		echo "INFO: No update needed. Already at version '$TERMUX_PKG_VERSION'."
		return 0
	fi

	latest_commit_date_tz=$(curl -s "https://api.github.com/repos/kpet/clvk/commits/$latest_commit" | jq .commit.committer.date | sed -e 's|\"||g')

	if [ -z "$latest_commit_date_tz" ]; then
		termux_error_exit "ERROR: Unable to get latest commit date info"
	fi

	latest_commit_date=$(echo "$latest_commit_date_tz" | sed -e 's|\(.*\)T\(.*\)Z|\1|' -e 's|\-||g')
	latest_commit_time=$(echo "$latest_commit_date_tz" | sed -e 's|\(.*\)T\(.*\)Z|\2|' -e 's|\:||g')

	# https://github.com/termux/termux-packages/issues/11827
	# really fix it by including longer date time info into versioning
	# always check this in case upstream change the version format
	latest_version="0.0.${latest_commit_date}.${latest_commit_time}g${latest_commit:0:8}"

	if ! dpkg --compare-versions "$latest_version" gt "$TERMUX_PKG_VERSION"; then
		termux_error_exit "ERROR: Resulting latest version is not counted as update to the current version ($latest_version < $TERMUX_PKG_VERSION)"
	fi

	# unlikely to happen
	if [ "$latest_commit_date" -lt "$_COMMIT_DATE" ]; then
		termux_error_exit "ERROR: Upstream is older than current package version. Please report to upstream."
	elif [ "$latest_commit_date" -eq "$_COMMIT_DATE" ] && [ "$latest_commit_time" -lt "$_COMMIT_TIME" ]; then
		termux_error_exit "ERROR: Upstream is older than current package version. Please report to upstream."
	fi

	sed -i "${TERMUX_PKG_BUILDER_DIR}/build.sh" -e "s|^_COMMIT=.*|_COMMIT=${latest_commit}|"
	sed -i "${TERMUX_PKG_BUILDER_DIR}/build.sh" -e "s|^_COMMIT_DATE=.*|_COMMIT_DATE=${latest_commit_date}|"
	sed -i "${TERMUX_PKG_BUILDER_DIR}/build.sh" -e "s|^_COMMIT_TIME=.*|_COMMIT_TIME=${latest_commit_time}|"

	# maybe save a few ms as we already done version check
	termux_pkg_upgrade_version "$latest_version" --skip-version-check
}

termux_step_post_get_source() {
	git fetch --unshallow
	git checkout $_COMMIT
	git submodule update --init --recursive
	./external/clspv/utils/fetch_sources.py --deps llvm
}

termux_step_host_build() {
	termux_setup_cmake
	termux_setup_ninja

	cmake \
		-G Ninja \
		-S "$TERMUX_PKG_SRCDIR/external/clspv/third_party/llvm/llvm" \
		-DCMAKE_BUILD_TYPE=Release \
		-DLLVM_ENABLE_PROJECTS=clang
	cmake \
		--build "$TERMUX_PKG_HOSTBUILD_DIR" \
		-j "$TERMUX_MAKE_PROCESSES" \
		--target llvm-tblgen clang-tblgen
}

termux_step_pre_configure() {
	# from packages/libllvm/build.sh
	export _LLVM_DEFAULT_TARGET_TRIPLE=${CCTERMUX_HOST_PLATFORM/-/-unknown-}
	export _LLVM_TARGET_ARCH
	if [ "$TERMUX_ARCH" = arm ]; then
		_LLVM_TARGET_ARCH=ARM
	elif [ "$TERMUX_ARCH" = aarch64 ]; then
		_LLVM_TARGET_ARCH=AArch64
	elif [ "$TERMUX_ARCH" = i686 ] || [ "$TERMUX_ARCH" = x86_64 ]; then
		_LLVM_TARGET_ARCH=X86
	else
		termux_error_exit "Invalid arch: $TERMUX_ARCH"
	fi

	TERMUX_PKG_EXTRA_CONFIGURE_ARGS+=" -DLLVM_TARGET_ARCH=$_LLVM_TARGET_ARCH"
	TERMUX_PKG_EXTRA_CONFIGURE_ARGS+=" -DLLVM_TARGETS_TO_BUILD=$_LLVM_TARGET_ARCH"
	TERMUX_PKG_EXTRA_CONFIGURE_ARGS+=" -DLLVM_HOST_TRIPLE=$_LLVM_DEFAULT_TARGET_TRIPLE"

	# TERMUX_DEBUG_BUILD doesnt really have somewhere in between
	#TERMUX_PKG_EXTRA_CONFIGURE_ARGS+=" -DCMAKE_BUILD_TYPE=RelWithDebInfo"
	#export STRIP=:
}

termux_step_make_install() {
	# clvk does not have proper install rule yet
	install -Dm644 "$TERMUX_PKG_BUILDDIR/libOpenCL.so" "$TERMUX_PREFIX/lib/clvk/libOpenCL.so"

	echo "$TERMUX_PREFIX/lib/clvk/libOpenCL.so" > "$TERMUX_PKG_TMPDIR/clvk.icd"
	install -Dm644 "$TERMUX_PKG_TMPDIR/clvk.icd" "$TERMUX_PREFIX/etc/OpenCL/vendors/clvk.icd"
}