#!/bin/bash

# Copyright 2026  Heinz Wiesinger, Amsterdam, The Netherlands
# All rights reserved.
#
# Redistribution and use of this script, with or without modification, is
# permitted provided that the following conditions are met:
#
# 1. Redistributions of this script must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
#
#  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
#  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
#  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
#  EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
#  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
#  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
#  OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
#  WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
#  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
#  ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

cd $(dirname $0) ; CWD=$(pwd)

PKGNAM=sccache
VERSION=${VERSION:-$(echo $PKGNAM-*.tar.?z | rev | cut -f 3- -d . | cut -f 1 -d - | rev)}
BUILD=${BUILD:-2}

# Automatically determine the architecture we're building on:
if [ -z "$ARCH" ]; then
  case "$(uname -m)" in
    i?86) ARCH=i586 ;;
    arm*) readelf /usr/bin/file -A | egrep -q "Tag_CPU.*[4,5]" && ARCH=arm || ARCH=armv7hl ;;
    # Unless $ARCH is already set, use uname -m for all other archs:
    *) ARCH=$(uname -m) ;;
  esac
  export ARCH
fi

# If the variable PRINT_PACKAGE_NAME is set, then this script will report what
# the name of the created package would be, and then exit. This information
# could be useful to other scripts.
if [ ! -z "${PRINT_PACKAGE_NAME}" ]; then
  echo "$PKGNAM-$VERSION-$ARCH-$BUILD.txz"
  exit 0
fi

NUMJOBS=${NUMJOBS:-" -j$(expr $(nproc) + 1) "}

if [ "$ARCH" = "i586" ]; then
  SLKCFLAGS="-O2 -march=i586 -mtune=i686"
  LIBDIRSUFFIX=""
elif [ "$ARCH" = "i686" ]; then
  SLKCFLAGS="-O2 -march=i686"
  LIBDIRSUFFIX=""
elif [ "$ARCH" = "s390" ]; then
  SLKCFLAGS="-O2"
  LIBDIRSUFFIX=""
elif [ "$ARCH" = "x86_64" ]; then
  SLKCFLAGS="-O2 -fPIC"
  LIBDIRSUFFIX="64"
elif [ "$ARCH" = "armv7hl" ]; then
  SLKCFLAGS="-O3 -march=armv7-a -mfpu=vfpv3-d16"
  LIBDIRSUFFIX=""
else
  SLKCFLAGS="-O2"
  LIBDIRSUFFIX=""
fi

TMP=${TMP:-/tmp}
PKG=$TMP/package-$PKGNAM

rm -rf $PKG
mkdir -p $TMP $PKG

cd $TMP
rm -rf $PKGNAM-$VERSION
tar xvf $CWD/$PKGNAM-$VERSION.tar.?z || exit 1
cd $PKGNAM-$VERSION || exit 1
tar xvf $CWD/cargo-$PKGNAM-$VERSION.tar.?z || exit 1
mv cargo-$PKGNAM-$VERSION vendor

chown -R root:root .
find . \
  \( -perm 777 -o -perm 775 -o -perm 711 -o -perm 555 -o -perm 511 \) \
  -exec chmod 755 {} \+ -o \
  \( -perm 666 -o -perm 664 -o -perm 600 -o -perm 444 -o -perm 440 -o -perm 400 \) \
  -exec chmod 644 {} \+

# Build the distributed toolchain package from rustc's real target-libdir, and
# from only the files that are actually needed. Upstream looks in $sysroot/lib,
# which a distribution rustc reporting sysroot=/usr does not have on a multilib
# layout (it lives in /usr/lib64), so every distributed Rust compile fails and
# silently falls back to local - and packs all of /usr/bin along the way:
zcat $CWD/$PKGNAM-rust_toolchain_packaging.patch.gz | patch -p1 --verbose || exit 1

# With [dist] rewrite_includes_only = true, preprocessed .S files are still sent
# to the build server as "-x assembler-with-cpp", so gcc preprocesses them a
# second time and as chokes on the leading "# 0 <file>" linemarker. Unreported
# upstream; see the patch header:
zcat $CWD/$PKGNAM-asm_rewrite_includes_only.patch.gz | patch -p1 --verbose || exit 1

# gcc refuses -fdirectives-only together with -Wunused-macros, so with
# rewrite_includes_only = true every compile using that warning fails. Preprocess
# those fully instead, like upstream does for -pedantic; see the patch header:
zcat $CWD/$PKGNAM-unused_macros_rewrite_includes_only.patch.gz | patch -p1 --verbose || exit 1

# A non-zero exit from the build server is passed through as a real compiler
# error, so any input the compiler opens on its own - a rust proc macro reading
# a file, say - kills the build even though it compiles fine locally. Fall back
# to a local recompile instead; from upstream PR #2777, see the patch header:
zcat $CWD/$PKGNAM-dist_local_fallback.patch.gz | patch -p1 --verbose || exit 1

# Configure cargo for offline builds
mkdir -p .cargo
cat << EOF >> .cargo/config.toml

[source.crates-io]
replace-with = "vendored-sources"

[source.vendored-sources]
directory = "vendor"
EOF

CFLAGS="$SLKCFLAGS" \
CXXFLAGS="$SLKCFLAGS" \
cargo build \
  --offline \
  --release \
  --features all,dist-server \
  --target $ARCH-unknown-linux-gnu \
  $NUMJOBS || exit 1

mkdir -p $PKG/usr/bin

install -m 755 target/$ARCH-unknown-linux-gnu/release/sccache \
  $PKG/usr/bin/
install -m 755 target/$ARCH-unknown-linux-gnu/release/sccache-dist \
  $PKG/usr/bin/

mkdir -p $PKG/etc/rc.d
cp -a $CWD/rc.sccache-scheduler $PKG/etc/rc.d/rc.sccache-scheduler.new
cp -a $CWD/rc.sccache-server    $PKG/etc/rc.d/rc.sccache-server.new
cp -a $CWD/rc.sccache.conf      $PKG/etc/rc.d/rc.sccache.conf.new
chown root:root $PKG/etc/rc.d/*
chmod 644 $PKG/etc/rc.d/*

mkdir -p $PKG/etc/sccache
cp -a $CWD/scheduler.conf $PKG/etc/sccache/scheduler.conf.new
cp -a $CWD/server.conf    $PKG/etc/sccache/server.conf.new
chown root:root $PKG/etc/sccache/*
chmod 600 $PKG/etc/sccache/*

# Storage for the build server's toolchain cache / sandbox and the daemon logs:
mkdir -p $PKG/var/cache/sccache/toolchains
mkdir -p $PKG/var/cache/sccache/build
mkdir -p $PKG/var/log/sccache

# Masquerade symlinks for compilers sccache supports
mkdir -p $PKG/usr/libexec/sccache/bin
for i in \
  cc c++ gcc g++ \
  clang clang++ clang-cl \
  rustc clippy-driver \
  nvcc nvc nvc++ \
  hipcc \
  dcc dplus \
  cctc \
  $ARCH-slackware-linux-gcc $ARCH-slackware-linux-g++ $ARCH-slackware-linux-c++ \
  $ARCH-slackware-linux-clang $ARCH-slackware-linux-clang++ ; do
    ln -s /usr/bin/sccache $PKG/usr/libexec/sccache/bin/$i
done

find $PKG -print0 | xargs -0 file | grep -e "executable" -e "shared object" | grep ELF \
  | cut -f 1 -d : | xargs strip --strip-unneeded 2> /dev/null || true

mkdir -p $PKG/usr/doc/$PKGNAM-$VERSION
cp -a *.md LICENSE* docs/* \
  $PKG/usr/doc/$PKGNAM-$VERSION

# Commented starting point for the per-user client config (~/.config/sccache/
# config), which sccache never creates itself:
sed "s/sccache-VERSION/$PKGNAM-$VERSION/g" $CWD/client-config.example \
  > $PKG/usr/doc/$PKGNAM-$VERSION/client-config.example

mkdir -p $PKG/install
cat $CWD/slack-desc > $PKG/install/slack-desc
cat $CWD/doinst.sh > $PKG/install/doinst.sh

cd $PKG
/sbin/makepkg -l y -c n $TMP/$PKGNAM-$VERSION-$ARCH-$BUILD.txz