#!/bin/sh
# Builds a Debian package of Jarl: dist/jarl_<version>_<arch>.deb.
# Run through 'make deb' (which sets the variables below); needs only
# dpkg-deb, no root and no debhelper.
#
# The package installs, with Debian's paths:
#   /usr/bin/jarld, /usr/bin/jarl
#   /usr/share/bash-completion/completions/{jarl,jarld}
#   /usr/lib/systemd/system/jarl.service
#   /usr/lib/sysusers.d/jarl.conf, /usr/lib/tmpfiles.d/jarl.conf
#   /usr/share/doc/jarl/ (README, CHANGELOG, docs, contrib)
# and its scripts (deploy/debian) create the jarl user and directories and
# /etc/jarl/jarl.yaml on the first install, restart a running jarld on
# upgrades, and stop it on removal. No file in /etc belongs to the package,
# so an upgrade never asks about configuration files.
#
# Variables: DEB_ARCH (Debian architecture, e.g. amd64, arm64, armhf),
# DEB_VERSION, VERSION, LDFLAGS, GOFLAGS, and DEB_MAINTAINER (default: your
# git name and email).
set -eu

: "${DEB_ARCH:?}" "${DEB_VERSION:?}" "${VERSION:?}" "${LDFLAGS:?}"
GOFLAGS=${GOFLAGS:-}

# Debian architecture -> Go architecture.
goarm=
case "$DEB_ARCH" in
amd64) goarch=amd64 ;;
arm64) goarch=arm64 ;;
armhf) goarch=arm goarm=7 ;;
i386) goarch=386 ;;
ppc64el) goarch=ppc64le ;;
riscv64) goarch=riscv64 ;;
s390x) goarch=s390x ;;
*) echo "mkdeb: unsupported architecture $DEB_ARCH" >&2; exit 1 ;;
esac

if [ -z "${DEB_MAINTAINER:-}" ]; then
	name=$(git config user.name 2>/dev/null || true)
	email=$(git config user.email 2>/dev/null || true)
	DEB_MAINTAINER="${name:-Jarl packager} <${email:-root@localhost}>"
fi

work=dist/deb/jarl_${DEB_VERSION}_${DEB_ARCH}
root=$work/root
out=dist/jarl_${DEB_VERSION}_${DEB_ARCH}.deb
rm -rf "$work"
mkdir -p "$root/DEBIAN"

# Binaries for the package's architecture (bin/ holds the host's, which
# also generated the completion scripts).
echo "mkdeb: building for linux/$goarch"
# go reads GOFLAGS (-trimpath) from the environment.
export GOFLAGS
GOOS=linux GOARCH=$goarch GOARM=$goarm CGO_ENABLED=0 go build -ldflags "$LDFLAGS" -o "$work/jarld" ./cmd/jarld
GOOS=linux GOARCH=$goarch GOARM=$goarm CGO_ENABLED=0 go build -ldflags "$LDFLAGS" -o "$work/jarl" ./cmd/jarl

make --no-print-directory install-files DESTDIR="$root" PREFIX=/usr \
	UNITDIR=/usr/lib/systemd/system JARLD_BIN="$work/jarld" JARL_BIN="$work/jarl" >/dev/null

# Debian's machine-readable copyright file, from LICENSE and the bundled
# font's licence (the font is embedded in jarld's web UI).
indent() { sed -e 's/^$/./' -e 's/^/ /' "$1"; }
{
	echo "Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/"
	echo "Upstream-Name: jarl"
	echo
	echo "Files: *"
	echo "Copyright: $(sed -n 's/^Copyright (c) //p' LICENSE)"
	echo "License: Expat"
	indent LICENSE
	echo
	echo "Files: internal/web/static/assets/fonts/*"
	echo "Copyright: 2020 The Cinzel Project Authors"
	echo "License: OFL-1.1"
	indent internal/web/static/assets/fonts/Cinzel-OFL.txt
} > "$root/usr/share/doc/jarl/copyright"

for f in postinst prerm postrm; do
	install -m 0755 "deploy/debian/$f" "$root/DEBIAN/$f"
done
# Directories 0755 and no group/other write, whatever the build's umask.
find "$root" -type d -exec chmod 0755 {} +
chmod -R go-w "$root"
size=$(du -sk --exclude=DEBIAN "$root" | cut -f1)
sed -e "s/@VERSION@/$DEB_VERSION/" -e "s/@ARCH@/$DEB_ARCH/" -e "s/@SIZE@/$size/" \
	-e "s|@MAINTAINER@|$DEB_MAINTAINER|" deploy/debian/control.in > "$root/DEBIAN/control"
(cd "$root" && find . -path ./DEBIAN -prune -o -type f -print | sed 's|^\./||' | sort | xargs md5sum) > "$root/DEBIAN/md5sums"
chmod 0644 "$root/DEBIAN/control" "$root/DEBIAN/md5sums"

# Files belong to root in the package, whoever builds it.
dpkg-deb --root-owner-group -Zxz --build "$root" "$out" >/dev/null
rm -rf dist/deb
echo "mkdeb: wrote $out"
dpkg-deb --info "$out" | sed -n 's/^ \(Package\|Version\|Architecture\|Installed-Size\):/  \1:/p'