#!/bin/sh

# Amethyst bootstrap script that does the bs I don't want to do by hand every time I start from scratch.
# Written by Kana Steimle
# This script builds from source the minimum set of required packages to start using apb and bootstrap Amethyst Linux as a whole.
# These consist of the following packages: gcc, binutils, make, grep, sed, tar, gzip, oksh, coreutils, and wget.
# It will also build apm and apb for you, installing them in the cross/bin directory along with the cross compiler.
# If you're using pre-packaged sources, you can technically remove the tar, gzip, and wget bootstrap packages. But I'd still recommend keeping them until you know you don't need them.

# In addition to building packages for the local machine, this can also cross compile the packages for a different architecture.
# Pass the TARGET environment variable to specify the target machine's (and optionally the HOST environment variable too)
# Some of the generated packages aren't quite up to standard with my current packages... I'm working on it.

# For the sake of debugging: To start building from a particular step, pass the STEP environment variable
# To stop after finishing a particular step, pass the LASTSTEP environment variable

BASE="$(dirname "$(realpath $0)")"
SRC="${BASE}/src"
EXTSRC="${BASE}/extracted-src"
CROSS="${BASE}/cross"
PKGBS="${BASE}/pkg"
mkdir -p "${PKGBS}"

PATH="${CROSS}/bin:/usr/bin:/bin"

export MAKEFLAGS="-j$(nproc)"

[ -z "$STEP" ] && STEP=1

if [ -z "${HOST}" ]; then
	HOST=$(cc -dumpmachine)
fi
if [ -z "${TARGET}" ]; then
	TARGET=$(echo "${HOST}" | cut -d- -f1)-pc-linux-musl
	# Make sure gcc actually builds a cross compiler instead of a native compiler
	if [ "x${TARGET}" = "x${HOST}" ]; then
		TARGET=$(echo "${HOST}" | cut -d- -f1)-amethyst-linux-musl
	fi
fi

buildingpkg() {
	PACKAGE="$1"
	BUILD="${BASE}/$1_build"
	PKGOUT="${BUILD}/pkgout"
	mkdir -p "${BUILD}"
	cd "${BUILD}"
}

configure() {
	"${EXTSRC}/${PACKAGE}/configure" "$@"
}

strippkg() {
	for f in $(find "${PKGOUT}/bin" "${PKGOUT}/libexec" -type f -executable -exec file '{}' + | grep 'not stripped' | cut -d: -f1); do
		"${TARGET}-strip" "$f"
	done
}

package() {
	PWD_bak="${PWD}"
	cd "${PKGOUT}"
	switches="$1"
	shift
	set -- "$@" "${PKGBS}/${PACKAGE}${switches}.pkg"
	mksquashfs "$@" -all-root -noappend -no-strip
	cd "${PWD_bak}"
}

rmbuild() {
	cd "${BASEDIR}"
	rm -rf "${BUILD}"
}

nextstep() {
	if [ "${STEP}" = "${LASTSTEP}" ]; then
		exit 0
	fi
	STEP="$((STEP+1))"
}

set -ex

# Extract sources
mkdir -p "${EXTSRC}"
cd "${EXTSRC}"
for f in apm apb binutils gcc musl gmp mpfr mpc libressl make grep sed tar gzip oksh coreutils wget; do
	if ! [ -e $f ]; then
		tar -xf "${SRC}/$f-"*.tar.*
		mv $f-* $f
		case $f in
			gcc) [ "$(echo "${TARGET}" | cut -d- -f1)" = x86_64 ] && sed -i '/m64=/s/lib64/lib/' "${EXTSRC}/$f/gcc/config/i386/t-linux64" ;;
		esac
		for p in "${SRC}/$f-"*.patch; do
			[ -r "$p" ] && patch -p1 -d "${EXTSRC}/$f" -i "$p"
		done
	fi
done

# -- Phase 1: Cross tools --

# Step 1: apm
if [ 1 -eq "$STEP" ]; then
	buildingpkg apm
	configure --prefix="${CROSS}" --bindir="${CROSS}/bin" --disable-vim --disable-man --disable-doc
	make
	make install
	rmbuild
	nextstep
fi

# Step 2: apb
if [ 2 -eq "$STEP" ]; then
	buildingpkg apb
	configure --prefix="${CROSS}" --bindir="${CROSS}/bin" --disable-vim --disable-man --sysconfdir="${CROSS}/etc" --pkgdir="${PKGBS}"
	make
	make install
	rmbuild
	nextstep
fi

# Step 3: cross binutils
if [ 3 -eq "$STEP" ]; then
	buildingpkg binutils
	configure --prefix="${CROSS}" --host="${HOST}" --target="${TARGET}" --disable-nls --disable-gprofng --disable-gold
	make
	make install
	rmbuild
	nextstep
fi

# Step 4: cross gcc
if [ 4 -eq "$STEP" ]; then
	buildingpkg gcc
	configure --prefix="${CROSS}" --host="${HOST}" --target="${TARGET}" --disable-nls --enable-languages=c,c++ --disable-multilib --disable-shared
	make all-gcc
	make install-gcc
	# Don't rmbuild because we're going to keep building from where we already are.
	nextstep
fi

# All the cross tools are built; strip them.
for f in $(find "${CROSS}"/bin "${CROSS}"/libexec -type f -executable -exec file '{}' + | grep 'not stripped' | cut -d: -f1); do
	strip $f
done

# -- Phase 2: Libraries --

# Step 5: musl
if [ 5 -eq "$STEP" ]; then
	buildingpkg musl
	configure --prefix="${CROSS}/${TARGET}" --build="${HOST}" --host="${TARGET}" --disable-shared
	make
	make install
	rmbuild
	nextstep
fi

# Step 6: libgcc and libstdc++-v3
if [ 6 -eq "$STEP" ]; then
	buildingpkg gcc
	# Use last configuration
	make all-target-libgcc all-target-libstdc++-v3
	make install-target-libgcc install-target-libstdc++-v3
	rmbuild
	nextstep
fi

# Steps 7-9: gmp, mpfr, mpc
RSTEP=7
for pkg in gmp mpfr mpc; do
	if [ $RSTEP -eq "$STEP" ]; then
		buildingpkg $pkg
		configure --prefix="${CROSS}/${TARGET}" --build="${HOST}" --host="${TARGET}" --disable-shared
		make
		make install
		rmbuild
		nextstep
	fi
	RSTEP=$((RSTEP+1))
done

# Step 10: libressl
if [ 10 -eq "$STEP" ]; then
	buildingpkg libressl
	configure --prefix="${CROSS}/${TARGET}" --sysconfdir=/etc --build="${HOST}" --host="${TARGET}" --disable-shared
	# We only want to build the libraries libcrypto and libssl
	make -C crypto
	make -C ssl
	# Install the libraries
	make -C crypto install
	make -C ssl install
	# Install the headers
	make -C include/openssl install
	# Install the configuration files and certificates as a package; wget can't use ssl without them
	make DESTDIR="${PKGOUT}" install-exec-hook
	package -certs-bootstrap etc/ssl/cert.pem
	rmbuild
	nextstep
fi

# -- Phase 3: Native tools --

# Step 11: binutils
if [ 11 -eq "$STEP" ]; then
	buildingpkg binutils
	configure --prefix='' --build="${HOST}" --host="${TARGET}" --disable-nls --disable-gprofng --disable-gold --disable-shared
	make
	make install DESTDIR="${PKGOUT}" tooldir=
	strippkg
	package -bin-bootstrap-musl-static bin lib/ldscripts
	rmbuild
	nextstep
fi

# Step 12: gcc
if [ 12 -eq "$STEP" ]; then
	buildingpkg gcc
	configure --prefix='' --build="${HOST}" --host="${TARGET}" --target="${TARGET}" --disable-nls --enable-languages=c,c++ --disable-multilib --disable-shared --disable-lto CFLAGS_FOR_TARGET="-fPIE" CXXFLAGS_FOR_TARGET="-fPIE" LDFLAGS_FOR_TARGET="-fPIE"
	make all-gcc all-target-libgcc all-target-libstdc++-v3
	make install-gcc install-target-libgcc install-target-libstdc++-v3 DESTDIR="${PKGOUT}"
	ln -sf gcc "${BUILD}/pkgout/bin/cc"
	ln -sf gcc "${BUILD}/pkgout/bin/${TARGET}-cc"
	strippkg
	package -bin-bootstrap-musl-static bin libexec
	package -lib-bootstrap-musl-static lib
	package -headers-bootstrap-musl-static include
	rmbuild
	nextstep
fi

# Step 13: oksh
if [ 13 -eq "$STEP" ]; then
	buildingpkg oksh
	# Bug in oksh Makefile; it won't be able to install manpages unless they're in the build directory
	cp "${EXTSRC}/${PACKAGE}/"*.1 "${BUILD}/"
	configure --prefix='' --cc="${TARGET}-gcc"
	make
	make install DESTDIR="${PKGOUT}"
	cp sh.1 "${BUILD}/pkgout/share/man/man1/"
	ln -sf oksh "${BUILD}/pkgout/bin/sh"
	strippkg
	package -bin-bootstrap-musl-static bin
	rmbuild
	nextstep
fi

# Step 14: coreutils
if [ 14 -eq "$STEP" ]; then
	buildingpkg coreutils
	configure --prefix='' --host="${TARGET}" --disable-nls --disable-shared --enable-single-binary=symlinks --enable-no-install-program=stdbuf
	make
	make install DESTDIR="${PKGOUT}"
	strippkg
	package -bin-bootstrap-musl-static bin
	rmbuild
	nextstep
fi

# Step 15-19: make, grep, sed, tar, and gzip
RSTEP=15
for pkg in make grep sed tar gzip; do
	if [ $RSTEP -eq "$STEP" ]; then
		buildingpkg $pkg
		configure --prefix='' --host="${TARGET}" --disable-nls
		make
		make install DESTDIR="${PKGOUT}"
		strippkg
		package -bin-bootstrap-musl-static bin
		rmbuild
		nextstep
	fi
	RSTEP=$((RSTEP+1))
done

# Step 20: wget
if [ 20 -eq "$STEP" ]; then
	buildingpkg wget
	# There's a bunch of host libraries it'll try to use if we don't explicitly tell it not to
	configure --prefix='' --host="${TARGET}" --with-ssl=openssl --disable-pcre --disable-pcre2 --without-zlib --without-libpsl --disable-iri --disable-nls
	make
	make install DESTDIR="${PKGOUT}"
	strippkg
	package -bin-bootstrap-musl-static bin
	rmbuild
	nextstep
fi