#!/bin/bash

set -e
set -o nounset
set -o errexit

type git >/dev/null 2>&1 || { echo >&2 "git required. Aborting."; exit 1; }
type ccache >/dev/null 2>&1 || { echo >&2 "ccache required. Aborting."; exit 1; }

SDK="OpenWrt-SDK-mvebu_gcc-4.8-linaro_musl-1.1.15_eabi.Linux-x86_64"
sdk_url="https://repo.turris.cz/omnia/${SDK}.tar.bz2"
lede_dir="lede"
wireguard_path="${lede_dir}/package/network/services/wireguard"
arm_cc="${SDK}/staging_dir/toolchain-arm_cortex-a9+vfpv3_gcc-4.8-linaro_musl-1.1.15_eabi/bin/arm-openwrt-linux-g++"
arm_ld="${SDK}/staging_dir/toolchain-arm_cortex-a9+vfpv3_gcc-4.8-linaro_musl-1.1.15_eabi/bin/arm-openwrt-linux-ld"
kernel_dir="${SDK}/build_dir/target-arm_cortex-a9+vfpv3_musl-1.1.15_eabi/linux-mvebu/linux-4.4.91/arch/arm/kernel"

if [ ! -d $SDK ]; then
    echo "Downloading and extracting SDK..."
    wget $sdk_url
    tar xf $SDK.tar.bz2
    rm -f $SDK.tar.bz2
fi

echo "Building for ${SDK}"

echo "Updating checkout..."

if [ -d $lede_dir ]; then
    pushd $lede_dir
    git pull
    popd
else
    git clone https://github.com/lede-project/source/ $lede_dir
fi

rsync -aP $wireguard_path $SDK/package

if [ ! -f $kernel_dir/module.lds ]; then
    echo -e "SECTIONS {\n\t.core.plt : { BYTE(0) }\n\t.init.plt : { BYTE(0) }\n}" > $kernel_dir/module.lds
fi

echo "Building..."

make CXX=$arm_cc LD=$arm_ld V=s -C $SDK -j 5

rsync --remove-source-files $SDK/bin/mvebu-musl/packages/base/*.ipk ./

echo "Done."