#!/bin/bash

set -euo pipefail

declare -r WRAPPER="fakechroot -- fakeroot"

declare -r GROUP="$1"
declare -r BUILDDIR="$2"
declare -r OUTPUTDIR="$3"

mkdir -vp "$BUILDDIR/alpm-hooks/usr/share/libalpm/hooks"
find /usr/share/libalpm/hooks -exec ln -sf /dev/null "$BUILDDIR/alpm-hooks"{} \;

mkdir -vp "$BUILDDIR/var/lib/pacman/" "$OUTPUTDIR"
[[ "$GROUP" == "multilib-devel" ]] && pacman_conf=multilib.conf || pacman_conf=extra.conf
install -Dm644 "/usr/share/devtools/pacman.conf.d/$pacman_conf" "$BUILDDIR/etc/pacman.conf"

awk '
    {
        print
        if ($0 ~ /^Include *=/ && !found++) {
            last_include_line = NR
        }
    }
    END {
        if (last_include_line) {
            print "\n[ppr]"
            print "SigLevel = Never"
            print "Include = /etc/pacman.d/parch-mirrors"
            print ""
            print "[pcp]"
            print "SigLevel = Never"
            print "Include = /etc/pacman.d/parch-mirrors"   
        }
    }
' "$BUILDDIR/etc/pacman.conf" > "$BUILDDIR/etc/pacman.conf.tmp" && mv "$BUILDDIR/etc/pacman.conf.tmp" "$BUILDDIR/etc/pacman.conf"

cat pacman-conf.d-noextract.conf >> "$BUILDDIR/etc/pacman.conf"

sed 's/Include = /&rootfs/g' < "$BUILDDIR/etc/pacman.conf" > pacman.conf

sed -i '/#DisableSandbox/{c\
# No kernel landlock in containerd\
DisableSandbox
}' "$BUILDDIR/etc/pacman.conf"

cp --recursive --preserve=timestamps rootfs/* "$BUILDDIR/"

$WRAPPER -- \
    pacman -Sy -r "$BUILDDIR" \
        --noconfirm --dbpath "$BUILDDIR/var/lib/pacman" \
        --config pacman.conf \
        --noscriptlet \
        --hookdir "$BUILDDIR/alpm-hooks/usr/share/libalpm/hooks/" base "$GROUP"

$WRAPPER -- chroot "$BUILDDIR" update-ca-trust
$WRAPPER -- chroot "$BUILDDIR" pacman-key --init
$WRAPPER -- chroot "$BUILDDIR" pacman-key --populate

$WRAPPER -- chroot "$BUILDDIR" /usr/bin/systemd-sysusers --root "/"

sed -i -e 's/^root::/root:!:/' "$BUILDDIR/etc/shadow"

fakeroot -- \
    tar \
        --numeric-owner \
        --xattrs \
        --acls \
        --exclude-from=exclude \
        -C "$BUILDDIR" \
        -c . \
        -f "$OUTPUTDIR/$GROUP.tar"

cd "$OUTPUTDIR"
zstd --long -T0 -8 "$GROUP.tar"
sha256sum "$GROUP.tar.zst" > "$GROUP.tar.zst.SHA256"