#!/bin/bash

llvm_config=$1
llvm_codegen_libs="$2"
llvm_extra_libs="${@:3}"

use_llvm_config=1
llvm_host_win32=0
llvm_host_win32_wsl=0
llvm_host_win32_cygwin=0

function win32_format_path {
	local formatted_path=$1
	if  [[ $llvm_host_win32_wsl = 1 ]] && [[ $1 != "/mnt/"* ]]; then
		# if path is not starting with /mnt under WSL it could be a windows path, convert using wslpath.
		formatted_path="$(wslpath -a "$1")"
	elif [[ $llvm_host_win32_cygwin = 1 ]] && [[ $1 != "/cygdrive/"* ]]; then
		# if path is not starting with /cygdrive under CygWin it could be a windows path, convert using cygpath.
		formatted_path="$(cygpath -a "$1")"
	fi
	echo "$formatted_path"
}

if [[ $llvm_config = *".exe" ]]; then
	llvm_host_win32=1
	# llvm-config is a windows binary. Check if we are running CygWin or WSL since then we might still be able to run llvm-config.exe
	host_uname="$(uname -a)"
	case "$host_uname" in
		*Microsoft*)
			use_llvm_config=1
			llvm_host_win32_wsl=1
			;;
		CYGWIN*)
			use_llvm_config=1
			llvm_host_win32_cygwin=1
			;;
		*)
			use_llvm_config=0
	esac
fi

if [[ $llvm_host_win32 = 1 ]]; then
	llvm_config=$(win32_format_path "$llvm_config")
fi

if [[ $use_llvm_config = 1 ]]; then
	llvm_api_version=`$llvm_config --mono-api-version` || "0"
	with_llvm=`$llvm_config --prefix`
	llvm_config_cflags=`$llvm_config --cflags`
	llvm_system=`$llvm_config --system-libs`
	llvm_core_components=`$llvm_config --libs analysis core bitwriter`
	if [[ $llvm_api_version -lt 600 ]]; then
		llvm_old_jit=`$llvm_config --libs mcjit jit 2>>/dev/null`
	else
		llvm_old_jit=`$llvm_config --libs mcjit 2>>/dev/null`
	fi
	llvm_new_jit=`$llvm_config --libs orcjit 2>>/dev/null`

	if [[ ! -z $llvm_codegen_libs ]]; then
		llvm_extra=`$llvm_config --libs $llvm_codegen_libs`
	fi

	# When building for Windows subsystem using WSL or CygWin the path returned from llvm-config.exe
	# could be a Windows style path, make sure to format it into a path usable for WSL/CygWin.
	if [[ $llvm_host_win32 = 1 ]]; then
		with_llvm=$(win32_format_path "$with_llvm")
	fi
fi

# When cross compiling for Windows on system not capable of running Windows binaries, llvm-config.exe can't be used to query for
# LLVM parameters. In that scenario we will need to fallback to default values.
if [[ $llvm_host_win32 = 1 ]] && [[ $use_llvm_config = 0 ]]; then
	# Assume we have llvm-config sitting in llvm-install-root/bin directory, get llvm-install-root directory.
	with_llvm="$(dirname $llvm_config)"
	with_llvm="$(dirname $with_llvm)"
	llvm_config_path=$with_llvm/include/llvm/Config/llvm-config.h

	# llvm-config.exe --mono-api-version
	llvm_api_version=`awk '/MONO_API_VERSION/ { print $3 }' $llvm_config_path`

	# llvm-config.exe --cflags, returned information currently not used.
	llvm_config_cflags=

	# llvm-config.exe --system-libs
	if [[ $llvm_api_version -lt 600 ]]; then
		llvm_system="-limagehlp -lpsapi -lshell32"
	else
		llvm_system="-lpsapi -lshell32 -lole32 -luuid -ladvapi32"
	fi

	# llvm-config.exe --libs analysis core bitwriter
	if [[ $llvm_api_version -lt 600 ]]; then
		llvm_core_components="-lLLVMBitWriter -lLLVMAnalysis -lLLVMTarget -lLLVMMC -lLLVMCore -lLLVMSupport"
	else
		llvm_core_components="-lLLVMBitWriter -lLLVMAnalysis -lLLVMProfileData -lLLVMObject -lLLVMMCParser -lLLVMMC -lLLVMBitReader -lLLVMCore -lLLVMBinaryFormat -lLLVMSupport -lLLVMDemangle"
	fi

	# llvm-config.exe --libs mcjit jit
	if [[ $llvm_api_version -lt 600 ]]; then
		llvm_old_jit="-lLLVMJIT -lLLVMCodeGen -lLLVMScalarOpts -lLLVMInstCombine -lLLVMTransformUtils -lLLVMipa -lLLVMAnalysis -lLLVMMCJIT -lLLVMTarget -lLLVMRuntimeDyld -lLLVMObject -lLLVMMCParser -lLLVMBitReader -lLLVMExecutionEngine -lLLVMMC -lLLVMCore -lLLVMSupport"
	else
		# Current build of LLVM 60 for cross Windows builds doesn't support LLVM JIT.
		llvm_old_jit=
	fi

	# LLVM 36 doesn't support new JIT and LLVM 60 is build without LLVM JIT support for cross Windows builds.
	llvm_new_jit=

	# Check codegen libs and add needed libraries.
	case "$llvm_codegen_libs" in
		*x86codegen*)
			# llvm-config.exe --libs x86codegen
			if [[ $llvm_api_version -lt 600 ]]; then
				llvm_extra="-lLLVMX86CodeGen -lLLVMX86Desc -lLLVMX86Info -lLLVMObject -lLLVMBitReader -lLLVMMCDisassembler -lLLVMX86AsmPrinter -lLLVMX86Utils -lLLVMSelectionDAG -lLLVMAsmPrinter -lLLVMMCParser -lLLVMCodeGen -lLLVMScalarOpts -lLLVMInstCombine -lLLVMTransformUtils -lLLVMipa -lLLVMAnalysis -lLLVMTarget -lLLVMMC -lLLVMCore -lLLVMSupport"
			else
				llvm_extra="-lLLVMX86CodeGen -lLLVMGlobalISel -lLLVMX86Desc -lLLVMX86Info -lLLVMMCDisassembler -lLLVMX86AsmPrinter -lLLVMX86Utils -lLLVMSelectionDAG -lLLVMAsmPrinter -lLLVMDebugInfoCodeView -lLLVMDebugInfoMSF -lLLVMCodeGen -lLLVMTarget -lLLVMScalarOpts -lLLVMInstCombine -lLLVMTransformUtils -lLLVMBitWriter -lLLVMAnalysis -lLLVMProfileData -lLLVMObject -lLLVMMCParser -lLLVMMC -lLLVMBitReader -lLLVMCore -lLLVMBinaryFormat -lLLVMSupport -lLLVMDemangle"
			fi
			;;
		*armcodegen*)
			# llvm-config.exe --libs armcodegen
			if [[ $llvm_api_version -lt 600 ]]; then
				llvm_extra="-lLLVMARMCodeGen -lLLVMSelectionDAG -lLLVMAsmPrinter -lLLVMMCParser -lLLVMCodeGen -lLLVMScalarOpts -lLLVMInstCombine -lLLVMTransformUtils -lLLVMipa -lLLVMAnalysis -lLLVMTarget -lLLVMCore -lLLVMARMDesc -lLLVMMCDisassembler -lLLVMARMInfo -lLLVMARMAsmPrinter -lLLVMMC -lLLVMSupport"
			else
				llvm_extra="-lLLVMARMCodeGen -lLLVMGlobalISel -lLLVMSelectionDAG -lLLVMAsmPrinter -lLLVMDebugInfoCodeView -lLLVMDebugInfoMSF -lLLVMCodeGen -lLLVMTarget -lLLVMScalarOpts -lLLVMInstCombine -lLLVMTransformUtils -lLLVMBitWriter -lLLVMAnalysis -lLLVMProfileData -lLLVMObject -lLLVMMCParser -lLLVMBitReader -lLLVMCore -lLLVMBinaryFormat -lLLVMARMDesc -lLLVMMCDisassembler -lLLVMARMInfo -lLLVMARMAsmPrinter -lLLVMARMUtils -lLLVMMC -lLLVMSupport -lLLVMDemangle"
			fi
			;;
		*aarch64codegen*)
			# llvm-config.exe --libs aarch64codegen
			if [[ $llvm_api_version -lt 600 ]]; then
				llvm_extra="-lLLVMAArch64CodeGen -lLLVMSelectionDAG -lLLVMAsmPrinter -lLLVMMCParser -lLLVMCodeGen -lLLVMScalarOpts -lLLVMInstCombine -lLLVMTransformUtils -lLLVMipa -lLLVMAnalysis -lLLVMTarget -lLLVMCore -lLLVMAArch64Desc -lLLVMAArch64Info -lLLVMAArch64AsmPrinter -lLLVMMC -lLLVMAArch64Utils -lLLVMSupport"
			else
				llvm_extra="-lLLVMAArch64CodeGen -lLLVMGlobalISel -lLLVMSelectionDAG -lLLVMAsmPrinter -lLLVMDebugInfoCodeView -lLLVMDebugInfoMSF -lLLVMCodeGen -lLLVMTarget -lLLVMScalarOpts -lLLVMInstCombine -lLLVMTransformUtils -lLLVMBitWriter -lLLVMAnalysis -lLLVMProfileData -lLLVMObject -lLLVMMCParser -lLLVMBitReader -lLLVMCore -lLLVMBinaryFormat -lLLVMAArch64Desc -lLLVMAArch64Info -lLLVMAArch64AsmPrinter -lLLVMMC -lLLVMAArch64Utils -lLLVMSupport -lLLVMDemangle"
			fi
			;;
		*)
			llvm_extra=$llvm_codegen_libs
	esac
fi

if [[ $llvm_config_cflags = *"stdlib=libc++"* ]]; then
	llvm_libc_c="-stdlib=libc++"
	# llvm_libc_link="-lc++"
else
	llvm_libc_c=""
	# llvm_libc_link="-lstdc++"
fi

if [[ $llvm_host_win32 = 1 ]]; then
	host_cxxflag_additions="-std=gnu++11"
	host_cflag_additions="-DNDEBUG"
else
	host_cxxflag_additions="-std=c++11"
	host_cflag_additions=""
fi

if [[ ! -z $llvm_extra_libs ]]; then
	llvm_extra="$llvm_extra $llvm_extra_libs"
fi

# llvm-config --clfags adds warning and optimization flags we don't want
cflags_additions="-I$with_llvm/include -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -DLLVM_API_VERSION=$llvm_api_version $llvm_libc_c $host_cflag_additions"

cxxflag_additions="-fno-rtti -fexceptions $host_cxxflag_additions"

ldflags="-L$with_llvm/lib"

llvm_lib_components="$llvm_core_components $llvm_old_jit $llvm_new_jit $llvm_extra"

echo "LLVM_CFLAGS_INTERNAL=$cflags_additions"
echo "LLVM_CXXFLAGS_INTERNAL=$cflags_additions $cxxflag_additions"
echo "LLVM_LDFLAGS_INTERNAL=$ldflags"
echo "LLVM_LIBS_INTERNAL=$llvm_lib_components $ldflags $llvm_system $llvm_libc_link"