#!/bin/bash
set -e

# Ensure all output is in English and consistent.
# Also needed because the output of some commands is tested.
export LANG=C
unset LC_ALL LANGUAGE

# Overridable environment variables for uploading.

# Setting RESTRICTED_SSH makes the upload be done by sending a
# tarball across ssh, which is slow. It's faster to not set it,
# and instead configure authorized_keys to run d-i-unpack-helper,
# now that d-i-unpack-helper supports rsync mode. (The name of this
# variable is a historical accident, since rsync mode with
# d-i-unpack-helper is just as restricted.)
RESTRICTED_SSH=

SSHKEY=
SSHKEY=${SSHKEY:+-i $SSHKEY}
HELPER=${HELPER:-d-i-unpack-helper}

if [ -z "$HOST" ]; then
	HOST=people.debian.org
fi
if [ -z "$BASEDIR" ]; then
	# Please don't change this. If you need it to be something else,
	# override the variable.
	BASEDIR=public_html/d-i/images
fi
if [ -z "$SOURCE_DATE_EPOCH" ]; then
	export SOURCE_DATE_EPOCH=$(date -u +%s)
fi
if [ -z "$DIR" ]; then
	DIR=$(date -u '+%Y%m%d-%H:%M' -d@${SOURCE_DATE_EPOCH})
fi
if [ "$HOST" = local ]; then
	SYNC="rsync"
	SYNC_BASEDIR="$BASEDIR"
else
	CALL="ssh $SSHKEY $HOST"
	SYNC="rsync"
	SYNC_BASEDIR="$HOST:$BASEDIR"
	HELPER="ssh $SSHKEY $HOST $HELPER"
fi
if [ -z "$NUM_KEEP" ]; then
	# Default to keeping 30 days of builds. Set to zero to keep all.
	NUM_KEEP=30
fi

# Overridable environment variables for building.
if [ -z "$ROOTCMD" ]; then
	_ROOTCMD="fakeroot"
else
	_ROOTCMD=$ROOTCMD
	unset ROOTCMD
fi

# Internal environment variables to keep file attributes between targets
# when fakeroot is used.
# As we start with an empty file, we can use -i also on first invocation.
ROOTCMDOPTS=""
case "$_ROOTCMD" in
    *fakeroot*)
	FRSAVE="$(mktemp -t d-i_daily-build.XXXXXX)"
	trap 'rm -f $FRSAVE' 0 HUP INT QUIT TERM
	ROOTCMDOPTS="-i $FRSAVE -s $FRSAVE"
	;;
esac

LOG_TO_STDOUT=${LOG_TO_STDOUT:-0}

overview () {
	echo "$(dpkg --print-architecture) ($(date -u -d@${SOURCE_DATE_EPOCH})) $(whoami)@$(hostname | cut -d . -f 1) $1" >> dest/overview.log
}

header () {
	echo
	echo $@
	echo
}

do_build_helper () {
	local t=$1
	header BUILDING IMAGE FOR $t
	gitver=$(git show-ref HEAD 2>/dev/null) || true
	if [ -n "$gitver" ]; then
		echo "debian-installer git tree version: $gitver"
	elif [ -d ../.git ]; then
		githead=$(cat ../.git/refs/heads/master) || true
		echo "debian-installer git tree head: $githead"
	fi
	$_ROOTCMD $ROOTCMDOPTS make $t 2>&1
}

do_build () {
	local t=$1
	local err=0

	if [ "$LOG_TO_STDOUT" = 1 ]; then
		set -o pipefail
		ROOTCMDOPTS=$ROOTCMDOPTS do_build_helper $t | tee -a dest/$t.log || err=$?
		set +o pipefail
	else
		ROOTCMDOPTS=$ROOTCMDOPTS do_build_helper $t >> dest/$t.log || err=$?
	fi

	return $err
}

build () {
	# Override $TARGETS with custom makefile targets.
	if [ -z "$TARGETS" ]; then
		TARGETS="$($_ROOTCMD make all_list | grep '^build')"
	fi

	$_ROOTCMD make reallyclean > /dev/null
	mkdir dest
	touch dest/overview.log

	# Save file attributes within this loop if fakeroot is used
	for t in $TARGETS; do
		if do_build $t; then
			overview "$t success"
		else
			overview "$t failed"
			echo "building $t failed, see log file dest/$t.log for details" >&2
		fi
	done
	$_ROOTCMD make stats > dest/stats.txt 2>&1 || true
	make release > /dev/null
}

upload () {
	(
	header UPLOADING FILES
	if [ -n "$RESTRICTED_SSH" ]; then
		tar zcvf - -C dest/ . | $HELPER
	else
		$CALL mkdir -p $BASEDIR/${DIR}_RSYNC_IN_PROGRESS
		$CALL test ! -d $BASEDIR/daily || $CALL cp -a $BASEDIR/daily/* $BASEDIR/${DIR}_RSYNC_IN_PROGRESS/
		$SYNC --stats -rvlt --safe-links --delete --rsh="ssh $SSHKEY" dest/ $SYNC_BASEDIR/${DIR}_RSYNC_IN_PROGRESS/
		$CALL rm -rf $BASEDIR/$DIR
		$CALL mv $BASEDIR/${DIR}_RSYNC_IN_PROGRESS $BASEDIR/$DIR
		$CALL rm -rf $BASEDIR/daily
		$CALL ln -sf $DIR $BASEDIR/daily
	fi
	) > dest/upload.log 2>&1
}

trim () {
	if [ -z "$TRIM_LOG" ]; then
		TRIM_LOG=dest/trim.log
	fi
	(
	header TRIMMING OLD BUILDS
	if [ -n "$RESTRICTED_SSH" ]; then
		echo "(trim not implemented for RESTRICTED_SSH mode)"
	elif [ -n "$NUM_KEEP" ] && [ "$NUM_KEEP" != 0 ]; then
		DIR=$(dirname $0)
		$CALL find $BASEDIR -maxdepth 1 | egrep '/[0-9][0-9][0-9][0-9]+-?[0-9][0-9]-?[0-9][0-9]-?[0-9]*:?[0-9]*$' | \
			sort -n | "$DIR"/util/trim-daily-builds "$NUM_KEEP" | \
			$CALL xargs rm -rf
	else
		echo "(keeping all old builds)"
	fi
	) > $TRIM_LOG 2>&1
}

UPDATED=""
update () {
	if [ ! "$UPDATED" ]; then
		git pull >/dev/null 2>&1 || true
		UPDATED=1
	fi
}

deps () {
	temp=$(dpkg-checkbuilddeps -B ../debian/control 2>&1 || true)
	packages=$(echo $temp | sed -e 's%dpkg-checkbuilddeps: Unmet build dependencies: %%')
	apt-get update
	if [ "$packages" ]; then
		DEBIAN_PRIORITY=critical apt-get -y install $packages
	fi
	DEBIAN_PRIORITY=critical apt-get -y upgrade
}

usage () {
	echo These subcommands are available:
	awk -F\) '/subcommand$/ { print " ", $1 }' $0
	echo
}

if [ ! -d pkg-lists ]; then
	echo "You must run this from the build directory"
	exit 1
fi

case $1 in
	build-only) 	# subcommand
		build
	;;
	build) 	# subcommand
		update
		build
	;;
	upload)	# subcommand
		upload
	;;
	trim)	# subcommand
		trim
	;;
	'')	# no subcommand, for backwards compatability
		update
		build
		upload
		trim
	;;
	all)	# subcommand
		update
		build
		upload
		trim
	;;
	update)	# subcommand
		update
	;;
	deps)	# subcommand
		deps
	;;
	*)
		echo $1 is not a valid subcommand.
		usage
		exit 1
	;;
esac