#!/bin/bash

# Use special param to make sure we're running under bash (in case user does "sh install.sh")
[ "x$1" != "x--exec-self" ] && exec /bin/bash "$0" --exec-self "$@"

IGNORE_ERRORS=
while [ $# -gt 0 ]; do
	[ "x$1" = "x--ignore-errors" ] && IGNORE_ERRORS=jup
	shift
done

declare -rg SELFPID=$$
perror () {
	if [ -n "$IGNORE_ERRORS" ]; then
		echo "[ERROR] $@"
		return 0
	fi
	echo "[FATAL] $@"
	[ "$$" != "$SELFPID" ] && kill "$SELFPID"
	exit 1
}

if [ "$UID" != "0" ]; then
	perror "Must be running as root"
fi

# ** Extract value from text file containing key=value pairs
extractfield () {
	grep -m1 "^\s*$2\b" "$1" | awk -F '=' '{print $2}' | sed 's/\s//g'
}

# ** Wrap mysql command line client so we're always using the deb-sys-maint credentials
mysql () {
	"$(which mysql)" --defaults-extra-file=/etc/mysql/debian.cnf --default-character-set=utf8 "$@"
}

# ** Constants - to be patched by the packaging script
declare -rg TARGET_WEBIF_VERSION="%TARGET_WEBIF_VERSION%"
declare -rg PAYLOAD_OFFSET="%PAYLOAD_OFFSET%"

# ** Check if constants have been filled, bail out otherwise
if [ -z "$TARGET_WEBIF_VERSION" ] || [[ "$TARGET_WEBIF_VERSION" == %*% ]]; then
	perror "Bad upgrader: TARGET_WEBIF_VERSION not set"
fi
if [ -z "$PAYLOAD_OFFSET" ] || [[ "$PAYLOAD_OFFSET" == %*% ]]; then
	perror "Bad upgrader: PAYLOAD_OFFSET not set"
fi

# **********************************************************

# Get current webif version
declare -rg CURRENT_WEBIF_VERSION=$(mysql -e 'SELECT value FROM openslx.property WHERE name = "webif-version" LIMIT 1' | tail -n 1)
[ -z "$CURRENT_WEBIF_VERSION" ] && perror "Could not determine current webif version"
[ "$CURRENT_WEBIF_VERSION" -le "$TARGET_WEBIF_VERSION" ] || perror "This update seems to be older than the server version you're currently running"

# Extract payload
TMPDIR=$(mktemp -d)
[ -z "$TMPDIR" ] && perror "Could not create temporary directory for installer"
dd "bs=$PAYLOAD_OFFSET" "if=$0" skip=1 | tar -z -x -C "$TMPDIR"
RET=$?
[ "$RET" -ne 0 ] && perror "Extracting installer payload failed with exit code $RET"

echo "SLX-Admin: $CURRENT_WEBIF_VERSION -> $TARGET_WEBIF_VERSION"

# File end
exit 0
# Payload to follow