#! /bin/sh
config_host_mak="config-host.mak"

kern_ver=`uname -r`
objdir=$(pwd)/out
enable_lkm=NO
enable_libbpf=NO
enable_packages=NO
disable_libbpf=NO
static_link=no
enable_all=no
default_target=yes
kernel_bpf_support=NO
disable_list=test

usage() {
	echo "Usage: configure [options]"
	echo "options:"
	echo "  --kernel=KERNEL_VERSION    kernel version"
	echo "  --builddir=OBJDIR          the build dir"
	echo "  --enable-lkm               enable linux kernel module"
	echo "  --enable-libbpf            enable libbpf"
	echo "  --enable-packages          auto install dependent packages for tools"
	echo "  --disable-libbpf           disable all bpf tools"
	echo "  --enable-static            static link for c/cpp tools"
	echo "  --enable-target-xxx        xxx is the actual tool, like memleak, you may use --show-target to list all"
	echo "  --enable-target-all        enable all components"
	echo "  --disable-default          disable default components to built-in"
	echo "  --disable-target-xxx       xxx is the actual tool, like memleak, you may use --show-target to list all"
	echo "  --show-target              list all support tools"
}

check_bpf_kernel() {
	kern_major=$(echo $kern_ver | awk -F '.' '{print $1}')
	kern_minor=$(echo $kern_ver | awk -F '.' '{print $2}')
	is_centos7=$(echo $kern_ver | grep el7 | wc -l)

	if [ $((kern_major)) -ge 4 -a $((kern_minor)) -ge 4 ]; then
		kernel_bpf_support="YES"
	fi

	if [ $is_centos7 = 1 ]; then
		centos_minor=$(echo $kern_ver | awk -F '-' '{print $2}' | awk -F '.' '{print $1}')
		if [ $((centos_minor)) -ge 957 ];then
			kernel_bpf_support="YES"
		fi
	fi

	if [ $kernel_bpf_support != "YES" ];then
		echo "this kernel version not support ebpf"
		exit 1
	else
		echo "check kernel bpf support OK"
	fi
}

check_bpf_depend() {
	if [ ! -d "source/lib/internal/ebpf/coolbpf/build.sh" ];then
		echo "Cloning coolbpf"
		git submodule update --init
	fi

	check_bpf_kernel
	if [ $kernel_bpf_support = "YES" ];then
		clang -v > /dev/null
		if [ $? = 0 ];then
			echo "check clang OK"
		else
			echo "check clang failed, should intall first"
			exit 1
		fi
	fi
}

check_lkm_depend() {
	if [ ! -d "source/lib/internal/kernel_module" ];then
		echo "download sysak-module ... "
		wget https://gitee.com/anolis/sysak-module/repository/archive/master.zip -O sysak-module.zip
		echo "extract sysak-module"
		unzip sysak-module.zip -d source/lib/internal/
		mv source/lib/internal/sysak-module-master source/lib/internal/kernel_module
	fi

	rpm -q kernel-devel-$kern_ver > /dev/null
	if [ $? != 0 ];then
		echo "check kernel-devel-$kern_ver failed, should intall first"
		exit 1;
	fi
}

check_packages_depend() {
	PWD=$(pwd)
	PACKAGEBUILD_TMP="packagebuild_tmp"
	BUILD_SH="package_build.sh"
	SH_ABS_PATH=$(pwd)/$PACKAGEBUILD_TMP/$BUILD_SH

	mkdir -p $(pwd)/$PACKAGEBUILD_TMP
	if [ -f "$SH_ABS_PATH" ];then
		rm -f $SH_ABS_PATH
	fi

	echo "$(grep "DEP_PKG_INSTALL" $(pwd)/source/ -nr | awk -F ":=" '{print$2}'| tr -d "\"")"| while read line
	do
		echo $line
		OLDIFS="$IFS"
		IFS=@
		echo "cd $(pwd)/$PACKAGEBUILD_TMP" >> $SH_ABS_PATH
		for cmd in $line
		do
			echo $cmd >> $SH_ABS_PATH
			if [[ $cmd =~ "git clone" ]];then
				echo "WARNING:\"$cmd\" failed"
			fi
			#source $cmd
		done
		IFS="$OLDIFS"
		echo "cd $PWD" >> $SH_ABS_PATH
	done
	chmod +x $SH_ABS_PATH
	exec ./$PACKAGEBUILD_TMP/$BUILD_SH
	cd $PWD
}

check_depend() {
	if [ $enable_lkm = "YES" ]; then
		check_lkm_depend
	fi
	if [ $enable_libbpf = "YES" ]; then
		check_bpf_depend
	fi
	if [ $enable_packages = "YES" ]; then
		check_packages_depend
	fi
}

for opt; do
	optarg=$(expr "x$opt" : 'x[^=]*=\(.*\)')
	case "$opt" in
		--kernel=*)
			kern_ver=$optarg
			;;
		--builddir=*)
			objdir=$(readlink -f $optarg)
			;;
		--enable-lkm)
			enable_lkm="YES"
			;;
		--enable-libbpf)
			enable_libbpf="YES"
			;;
		--enable-packages)
			enable_packages="YES"
			;;
		--disable-libbpf)
			disable_libbpf="YES"
			;;
		--enable-static)
			static_link="yes"
			;;
		--enable-target-*)
			target=$(expr "$opt" : '--enable-target-\(.*\)')
			if [ $target = "all" ]; then
				enable_all="yes"
			else
				target_list="$target $target_list"
			fi
			;;
		--disable-default)
			default_target=no
			;;
		--disable-target-*)
			disable=$(expr "$opt" : '--disable-target-\(.*\)')
			disable_list="$disable|$disable_list"
			;;
		--show-target)
			find $(pwd)/source/tools/ -name Makefile -exec grep -H 'target :=' {} \; | awk '{print $3}' | grep -v test
			exit
			;;
		*)
			usage
			exit
			;;
	esac
done

if [ $default_target = "yes" ]; then
    target_list="tcp_syn_drop cpuirq sysmonitor cpu_flamegraph $target_list"
fi
for i in $target_list;do
	target_files="$(grep -nrw "target := $i" $(pwd)/source/tools/ | awk -F ":" '{print $1}') $target_files"
done

if [ $disable_libbpf = "YES" ]; then
	disable_target_1=$(grep "bpf\.mk" $(pwd)/source/tools/ -nEr --color | xargs -I {} expr {} : '.*/source/tools/\(.*\)/\(.*\)' |grep -E "combine|bpf_test|cgroup"|awk -F "/" '{print $2}' | uniq)
	for single_target_1 in $disable_target_1;do
		disable_list="$single_target_1|$disable_list"
	done
	disable_target_2=$(grep "bpf\.mk" $(pwd)/source/tools/ -nEr --color | xargs -I {} expr {} : '.*/source/tools/\(.*\)/\(.*\)' |grep -v -E "combine|bpf_test|cgroup"|awk -F "/" '{print $3}' | uniq)
	for single_target_2 in $disable_target_2;do
		disable_list="$single_target_2|$disable_list"
	done
fi

if [ $enable_all = "yes" ]; then
target_files=$(grep -nrw "target :=" $(pwd)/source/tools/ | grep -vwE $disable_list | awk -F ":" '{print $1}' | grep "Makefile")
fi

for file in $target_files;do
target_path=$(dirname $file)
target_paths="$target_path $target_paths"
grep -nrw modin $file > /dev/null
if [ $? = 0 ]; then
	echo "$target_path need lkm, you may set --enable-lkm"
fi

grep -nr "bpf.mk" $file > /dev/null
if [ $? = 0 ]; then
	enable_libbpf="YES"
	echo "$target_path need libbpf"
fi

done

check_depend

echo "# Automatically generated by configure - do not modify" > $config_host_mak

if [ $static_link = "yes" ]; then
echo "EXTRA_LDFLAGS = --static" >> $config_host_mak
fi

echo "KERNEL_VERSION = $kern_ver" >> $config_host_mak
echo "OBJPATH = $objdir" >> $config_host_mak
echo "BUILD_KERNEL_MODULE = $enable_lkm" >> $config_host_mak
echo "BUILD_LIBBPF = $enable_libbpf" >> $config_host_mak


echo "TARGET_LIST = $target_paths" >> $config_host_mak