#!/bin/bash
#
# Slackware build script for greetd
#
# Copyright 2023-2024 Jay Lanagan (j@lngn.net), Detroit, MI, USA.
# 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)

PRGNAM=greetd
PRGUID=greeter
PRGGID=greeter
VERSION=${VERSION:-0.10.3}
BUILD=${BUILD:-2}
TAG=${TAG:-_SBo}
PKGTYPE=${PKGTYPE:-tgz}

if [ -z "$ARCH" ]; then
  case "$( uname -m )" in
    i?86) ARCH=i586 ;;
    arm*) ARCH=arm ;;
       *) ARCH=$( uname -m ) ;;
  esac
fi

if [ ! -z "${PRINT_PACKAGE_NAME}" ]; then
  echo "$PRGNAM-$VERSION-$ARCH-$BUILD$TAG.$PKGTYPE"
  exit 0
fi

bailout() {
  printf "This requires a \"greeter\" user and group.\n"
  printf "groupadd -g 381 greeter\n"
  printf "useradd -d /var/lib/greeter -u 381 -g greeter -G video -s /bin/false greeter"
  exit 1
}

if ! getent group $PRGGID 2>/dev/null 1>/dev/null ; then
  bailout
elif ! getent passwd $PRGUID 2>/dev/null 1>/dev/null ; then
  bailout
fi

TMP=${TMP:-/tmp/SBo}
PKG=$TMP/package-$PRGNAM
OUTPUT=${OUTPUT:-/tmp}

if [ "$ARCH" = "i586" ]; then
  SLKCFLAGS="-O2 -march=i586 -mtune=i686"
  LIBDIRSUFFIX=""
elif [ "$ARCH" = "i686" ]; then
  SLKCFLAGS="-O2 -march=i686 -mtune=i686"
  LIBDIRSUFFIX=""
elif [ "$ARCH" = "x86_64" ]; then
  SLKCFLAGS="-O2 -fPIC"
  LIBDIRSUFFIX="64"
elif [ "$ARCH" = "aarch64" ]; then
  SLKCFLAGS="-O2 -fPIC"
  LIBDIRSUFFIX="64"
else
  SLKCFLAGS="-O2"
  LIBDIRSUFFIX=""
fi

export PATH="/opt/rust/bin:$PATH"
if [ -z "$LD_LIBRARY_PATH" ]; then
  export LD_LIBRARY_PATH="/opt/rust/lib$LIBDIRSUFFIX"
else
  export LD_LIBRARY_PATH="/opt/rust/lib$LIBDIRSUFFIX:$LD_LIBRARY_PATH"
fi

set -e

rm -rf $PKG
mkdir -p $TMP $PKG $OUTPUT
cd $TMP
rm -rf $PRGNAM-$VERSION
tar xvf $CWD/$VERSION.tar.?z || tar xvf $CWD/$PRGNAM-$VERSION.tar.?z
cd $PRGNAM-$VERSION

# build offline
# configuration tells cargo to use the configured directory
# for dependencies instead of downloading from crates.io
# borrowed from alacritty slackbuild
mkdir .cargo
cat << EOF >> .cargo/config
[source.crates-io]
registry = 'https://github.com/rust-lang/crates.io-index'
replace-with = 'vendored-sources'

[source.vendored-sources]
directory = '$(pwd)/vendor'
EOF

# deps and versions come from Cargo.lock
mkdir vendor
(
  cd vendor

  grep -h -A 4 "\[\[package\]\]" \
      $(find "../" -maxdepth 1 -mindepth 1 -name Cargo.lock | tr '\n' ' ') | \
      sed 's/[[:space:]]*=[[:space:]]*/=/g;s/^--//;s/^\[\[/--\n[[/' | \
      awk 'BEGIN { RS = "--\n" ; FS="\n" } { print $2, $3, $4, $5 }' | \
      sed 's/"//g;s/name=//;s/ version=/=/' | \
      grep " source=" | \
      sed 's/ dependencies=.*$//' | \
      sed 's/ source=[^ ]*//' | \
      sed 's/ checksum=/=/' | \
      sort -u | \
      while read -r dep ; do

    cksum="$(printf "%s\n" "$dep" | cut -d= -f3)"
    ver="$(printf "%s\n" "$dep" | cut -d= -f2)"
    dep="$(printf "%s\n" "$dep" | cut -d= -f1)"

    tar xvf $CWD/$dep-$ver.crate

    touch $dep-$ver/.cargo-ok

    # generate checksum
    {
      printf "{\n"
      printf '    "files": {\n'

      (
        cd $dep-$ver
        find . -type f -print0 | xargs -0 sha256sum | sed -n '/\.cargo-checksum\.json/!p' | sed 's/\.\///;s/^\([^ ]*\)[[:space:]][[:space:]]*\(.*\)$/"\2":"\1",/'
      ) | sed '$ s/,$//'

      printf "    },\n"
      printf '    "package": "%s"'  "$cksum"

      printf "}\n"
    } > $dep-$ver/.cargo-checksum.json
  done
)

chown -R root:root .
find -L . \
 \( -perm 777 -o -perm 775 -o -perm 750 -o -perm 711 -o -perm 555 \
  -o -perm 511 \) -exec chmod 755 {} \; -o \
 \( -perm 666 -o -perm 664 -o -perm 640 -o -perm 600 -o -perm 444 \
 -o -perm 440 -o -perm 400 \) -exec chmod 644 {} \;

# Set /bin/bash rather than /bin/sh as default shell
sed -i -e 's,vt = 1,vt = 7,g' config.toml
sed -i -e 's,bin/sh,bin/bash,g' config.toml

# Adding extra parms to default config to ensure our envir is good
cat <<EOT >> config.toml

[system]
source_profile = "true"
runfile = "/var/run/greetd.run"
EOT

## to do online rust build uncomment these two lines
#CARGO_HOME=.cargo cargo fetch --locked --target "$ARCH-unknown-linux-gnu"
#CARGO_HOME=.cargo cargo build --frozen --release --all-features

## and comment the line below this
CARGO_HOME=.cargo cargo build --offline --frozen --release --all-features
make -C man all

install -Dm0755 -t "$PKG/usr/bin/" "target/release/agreety"
install -Dm0755 -t "$PKG/usr/bin/" "target/release/fakegreet"
install -Dm0755 -t "$PKG/usr/bin/" "target/release/$PRGNAM"
install -Dm0644 -t "$PKG/etc/$PRGNAM/" config.toml
install -Dm0644 "$CWD/$PRGNAM.pam" "$PKG/etc/pam.d/$PRGNAM"
make -C man DESTDIR="$PKG" MANDIR=/usr/man PREFIX=/usr install

cd $TMP/$PRGNAM-$VERSION

find $PKG | xargs file | egrep "ELF.*executable" | cut -f 1 -d : \
          | xargs strip --strip-unneeded 2> /dev/null

# move this file to 'rc.4.local' for Slackware to boot directly
# to greetd from init level 4 startup
mkdir -p $PKG/etc/rc.d
cat $CWD/rc.4.$PRGNAM > $PKG/etc/rc.d/rc.4.$PRGNAM
chmod 0644 $PKG/etc/rc.d/rc.4.$PRGNAM

# create this in pkg to ensure it exists with proper perms
mkdir -p $PKG/var/lib/$PRGNAM
chown -R $PRGUID:$PRGGID $PKG/var/lib/$PRGNAM

gzip -9 $PKG/usr/man/man?/*

mkdir -p $PKG/usr/doc/$PRGNAM-$VERSION
cp -a LICENSE README.md \
      $PKG/usr/doc/$PRGNAM-$VERSION
cat $CWD/$PRGNAM.SlackBuild > $PKG/usr/doc/$PRGNAM-$VERSION/$PRGNAM.SlackBuild

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

cd $PKG
/sbin/makepkg -l y -c n $OUTPUT/$PRGNAM-$VERSION-$ARCH-$BUILD$TAG.$PKGTYPE