# --- T2-COPYRIGHT-NOTE-BEGIN ---
# T2 SDE: package/*/go/go.conf
# Copyright (C) 2021 - 2023 The T2 SDE Project
# 
# This Copyright note is generated by scripts/Create-CopyPatch,
# more information can be found in the files COPYING and README.
# 
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2.
# --- T2-COPYRIGHT-NOTE-END ---

autoextract=0
makeopt=
makeinstopt=

hook_add premake 5 "go_premake"
hook_add inmake 5 "go_inmake"
hook_add postmake 5 "go_postmake"

export GOROOT_FINAL=$root$libdir/go

# Translate our arch naming to theirs
translate_arch() {
	local ARCH=$1
	local ENDIAN=$2
	local TARGET_ARCH=$ARCH

	case $ENDIAN in
		yes) BE=be EB=eb LE='' ;;
		no) BE='' EB='' LE=le ;;
	esac

	case $ARCH in
		loongarch*) TARGET_ARCH=${ARCH/arch} ;;
		mips*) TARGET_ARCH=$ARCH$LE ;;
		powerpc64) TARGET_ARCH=ppc64$LE ;;
		x86) TARGET_ARCH=386 ;;
		x86-64|x86_64) TARGET_ARCH=amd64 ;;
	esac

	echo $TARGET_ARCH
}

go_premake() {
	export GOOS=$SDECFG_KERNEL
	#export GOHOSTARCH=$(go env | grep GOHOSTARCH | cut -d'"' -f2)
	#export GOHOSTARCH=$(translate_arch ${arch_build%%-*})
	export TARGET_ARCH=$(translate_arch $arch $arch_bigendian)
}

go_inmake() {
	# cross-compile using the compiler built at the toolchain stage
	if atstage cross; then
		export GOARCH=$TARGET_ARCH
		export CGO_ENABLED=0
		build_go
	fi

	# build the toolchain, first the one written in C then the one written in go
	# only the last one can be used for cross-compiling
	if atstage toolchain; then
		build_go 1.4
		build_go
	fi

	# build the C version if go is not installed and use it to build the latest
	# go version written in go
	if atstage native; then
		pkginstalled go || build_go 1.4
		build_go
	fi
}

go_postmake() {
	# delete previous go installs as it creates conflicts like redeclaration etc
	rm -rf $GOROOT_FINAL/

	mkdir -pv $GOROOT_FINAL
	cp -rfv go/* $GOROOT_FINAL/

	# place the cross-compiled binary in the right place as go puts it in
	# a subdirectory
	if atstage cross; then
		find "$GOROOT_FINAL/bin/${GOOS}_$GOARCH" -type f -perm /u+x | xargs -I {} mv -v {} $GOROOT_FINAL/bin/
		rm -rfv "$GOROOT_FINAL/bin/${GOOS}_$GOARCH"
	fi

	# symlink the binaries to the bindir
	for bin in $GOROOT_FINAL/bin/* ; do
		ln -srfv $bin $root/$bindir/${bin##*/}
	done
}

build_go() {
	# set TMPDIR, else it wants to use /var/tmp
	export TMPDIR="$(mktemp -d -p $PWD)"
	cd $TMPDIR

	# extract right go version
	[ "$1" == "1.4" ] && extract_go $1 || extract_go

	cd go/src

	# go uses uname all over the place to determine host arch, sigh
	sed -i 's,uname,/bin/uname,g' *.bash
	[ "$1" != "1.4" ] && sed -i '96s,uname,/bin/uname,g' ./cmd/dist/main.go &&
	export CGO_ENABLED=0

	# build
	./make.bash

	# set go1.4 as our toolchain for the next round to build go latest
	[ "$1" == "1.4" ] && export GOROOT_BOOTSTRAP="$TMPDIR/go"
	unset TMPDIR

	cd ../..
}

extract_go() {
	[ "$1" == "1.4" ] && VER="$1" || VER="$ver"
	tar $taropt "$(match_source_file -p go-$VER go)"
}