#!/usr/bin/env bash

TARGET="x86_64-elf"
LLVM_BRANCH="release_80"

TOOLS="clang lld" # lld libunwind libcxxabi libcxx"
PROJECTS="compiler-rt libcxxabi libcxx libunwind"
#RUNTIMES="compiler-rt libcxxabi libcxx libunwind"

set -e

README=$(realpath "$(dirname $0)/readme_for_prebuilt_sysroots.md")
SYSROOT=$(realpath "$(dirname $0)/../sysroot")
WORK=$(realpath "$(dirname $0)/sysroot")
mkdir -p "${SYSROOT}"
mkdir -p "${WORK}"

export CC=clang
export CXX=clang++

if [[ ! -d "${WORK}/llvm" ]]; then
	echo "Downloading LLVM..."
	git clone -q \
		--branch "${LLVM_BRANCH}" \
		--depth 1 \
		"https://git.llvm.org/git/llvm.git" "${WORK}/llvm"
fi

for tool in ${TOOLS}; do
	if [[ ! -d "${WORK}/llvm/tools/${tool}" ]]; then
		echo "Downloading ${tool}..."
		git clone -q \
			--branch "${LLVM_BRANCH}" \
			--depth 1 \
			"https://git.llvm.org/git/${tool}.git" "${WORK}/llvm/tools/${tool}"
	fi
done

if [[ ! -d "${WORK}/llvm/tools/clang/tools/extra" ]]; then
	echo "Downloading clang-tools-extra..."
	git clone -q \
		--branch "${LLVM_BRANCH}" \
		--depth 1 \
		"https://git.llvm.org/git/clang-tools-extra.git" "${WORK}/llvm/tools/clang/tools/extra"
fi

for proj in ${PROJECTS}; do
	if [[ ! -d "${WORK}/llvm/projects/${proj}" ]]; then
		echo "Downloading ${proj}..."
		git clone -q \
			--branch "${LLVM_BRANCH}" \
			--depth 1 \
			"https://git.llvm.org/git/${proj}.git" "${WORK}/llvm/projects/${proj}"
	fi
done

for proj in ${RUNTIMES}; do
	if [[ ! -d "${WORK}/llvm/runtimes/${proj}" ]]; then
		echo "Downloading ${proj}..."
		git clone -q \
			--branch "${LLVM_BRANCH}" \
			--depth 1 \
			"https://git.llvm.org/git/${proj}.git" "${WORK}/llvm/runtime/${proj}"
	fi
done

mkdir -p "${WORK}/build/llvm"
pushd "${WORK}/build/llvm"

echo "Configuring LLVM..."

cmake -G Ninja \
	-DCLANG_DEFAULT_RTLIB=compiler-rt \
	-DCLANG_DEFAULT_STD_C=c11 \
	-DCLANG_DEFAULT_STD_CXX=cxx14 \
	-DCMAKE_BUILD_TYPE=Release \
	-DCMAKE_C_COMPILER="clang" \
	-DCMAKE_CXX_COMPILER="clang++" \
	-DCMAKE_CXX_FLAGS="-Wno-unused-parameter -D_LIBCPP_HAS_NO_ALIGNED_ALLOCATION -D_LIBUNWIND_IS_BAREMETAL=1 -U_LIBUNWIND_SUPPORT_DWARF_UNWIND" \
	-DCMAKE_INSTALL_PREFIX="${SYSROOT}" \
	-DCMAKE_MAKE_PROGRAM=`which ninja` \
	-DDEFAULT_SYSROOT="${SYSROOT}" \
	-DLIBCXX_CXX_ABI=libcxxabi \
	-DLIBCXX_CXX_ABI_INCLUDE_PATHS="${WORK}/llvm/projects/libcxxabi/include" \
	-DLIBCXX_CXX_ABI_LIBRARY_PATH=lib \
	-DLIBCXX_ENABLE_EXPERIMENTAL_LIBRARY=OFF \
	-DLIBCXX_ENABLE_NEW_DELETE_DEFINITIONS=ON \
	-DLIBCXX_ENABLE_SHARED=OFF \
	-DLIBCXX_ENABLE_STATIC_ABI_LIBRARY=ON \
	-DLIBCXX_ENABLE_THREADS=OFF \
	-DLIBCXX_INCLUDE_BENCHMARKS=OFF \
	-DLIBCXX_USE_COMPILER_RT=ON \
	-DLIBCXXABI_ENABLE_NEW_DELETE_DEFINITIONS=OFF \
	-DLIBCXXABI_ENABLE_SHARED=OFF \
	-DLIBCXXABI_ENABLE_STATIC_UNWINDER=ON \
	-DLIBCXXABI_ENABLE_THREADS=OFF \
	-DLIBCXXABI_LIBCXX_PATH="${WORK}/llvm/projects/libcxx" \
	-DLIBCXXABI_USE_COMPILER_RT=ON \
	-DLIBCXXABI_USE_LLVM_UNWINDER=ON \
	-DLIBUNWIND_ENABLE_SHARED=OFF \
	-DLIBUNWIND_ENABLE_THREADS=OFF \
	-DLIBUNWIND_USE_COMPILER_RT=ON \
	-DLLVM_CONFIG_PATH="${SYSROOT}/bin/llvm-config" \
	-DLLVM_DEFAULT_TARGET_TRIPLE="x86_64-unknown-elf" \
	-DLLVM_ENABLE_LIBCXX=ON \
	-DLLVM_ENABLE_LLD=ON \
	-DLLVM_ENABLE_PIC=OFF \
	-DLLVM_ENABLE_THREADS=OFF \
	-DLLVM_INSTALL_BINUTILS_SYMLINKS=ON \
	-DLLVM_TARGETS_TO_BUILD="X86" \
	${WORK}/llvm > cmake_configure.log

#  -DCMAKE_ASM_COMPILER=nasm \
#  -DCMAKE_LINKER="${SYSROOT}/bin/ld.lld" \
#  -DCOMPILER_RT_ENABLE_LLD=ON \
#  -DLIBCXX_ENABLE_LLD=ON \
#  -DLIBCXX_ENABLE_STATIC_UNWINDER=ON \
#  -DLIBCXXABI_ENABLE_LLD=ON \
#  -DLIBUNWIND_ENABLE_LLD=ON \
#  -DLLVM_ENABLE_PROJECTS="libcxx;libcxxabi;libunwind;compiler-rt" \
#  -DCOMPILER_RT_BAREMETAL_BUILD=ON \
#  -DLIBCXXABI_BAREMETAL=ON \

echo "Building LLVM..."
ninja && ninja install
ninja cxx cxxabi compiler-rt
ninja install-compiler-rt install-cxx install-cxxabi
popd


cp "${README}" "${SYSROOT}/README.md"