#!/bin/bash

# update mode for zypper
# dup or up
ZYPPER_OFFLINE_UPDATE_MODE=up

# include recommended patches
# yes or no
ZYPPER_OFFLINE_UPDATE_RECOMENDS=no

ZYPPER_OFFLINE_UPDATE_STATUS_FILE=/var/run/zypper-update-triggered

INSTALL_LOG=/tmp/zypper-offline-update.log

#pid file
PIDFILE=/var/run/zypper-offline-update.pid

if [ -e /etc/sysconfig/zypper-offline-update ]; then
        . /etc/sysconfig/zypper-offline-update
fi

if [ $ZYPPER_OFFLINE_UPDATE_RECOMENDS = no ]; then
        NORECOMMENDS=--no-recommends
fi

function usage() {
        echo "usage:"
        echo "$0 start Start service for waiting to shutdown"
        echo "$0 stop  Run updates before shutdown"
        echo "$0 drystop Run without installing anything - for testing purposes only"
        exit 1
}
function handle_term_signal() {
    exit 0
}
function log() {
        LEVEL=$1
        MESSAGE=$2
        echo $MESSAGE 
        echo $MESSAGE | systemd-cat -t zypper-auto-update -p $LEVEL
        if [ ! -z $ZYPPER_OFFLINE_UPDATE_MAIL_TO ]; then
                HOST=$(hostname)
                RUNDATE=$(date '+%d.%m.%Y %H:%M:%S')
                LOGDATA="no log output"
                if [ -e $INSTALL_LOG ]; then
                        LOGDATA=$(cat $INSTALL_LOG)
                fi
                mailx -s "$HOST $LEVEL: $MESSAGE" $ZYPPER_OFFLINE_UPDATE_MAIL_TO <<EOF
This mail is for information only.
The zypper-offline-update process on $HOST was run on $RUNDATE.
Result of offline update is:
$MESSAGE

LOG from zypper:
================
$LOGDATA
EOF
                echo "sent email!"
        fi
}
trap handle_term_signal SIGTERM

if [ X$1 = "X" ]; then
        usage
else
        action=$1
fi

if [ $action = "start" ]; then
        nohup $0 run &
fi
if [ $action = "run" ]; then
        echo $$ > $PIDFILE
        while true
        do
            sleep 1
        done
fi
DOWNLOADSTATE=0
if [ $action = "stop" -o $action = "drystop" ]; then
    # Check if updates were downloaded successfully
    if [ -f $ZYPPER_OFFLINE_UPDATE_STATUS_FILE ]; then
        DOWNLOADSTATE=$(cat $ZYPPER_OFFLINE_UPDATE_STATUS_FILE)
    fi

    if [ $DOWNLOADSTATE -eq 1 ]; then
        # Apply updates
        if [ $action = "drystop" ]; then
            echo "dry run has no output from zypper" > $INSTALL_LOG
            log "info" "Dry run of offline updates"
        else
            /usr/bin/zypper $ZYPPER_OFFLINE_UPDATE_MODE -y $NORECOMMENDS > $INSTALL_LOG
            ZYPPERSTATE=$?
            cat $INSTALL_LOG
            if [ $ZYPPERSTATE -eq 103 ]; then
              log "info" "The Zypper package was patched, rerunning update to apply remaining patches."
              rm $INSTALL_LOG
              /usr/bin/zypper $ZYPPER_OFFLINE_UPDATE_MODE -y $NORECOMMENDS > $INSTALL_LOG
              ZYPPERSTATE=$?
              cat $INSTALL_LOG
            fi
            if [ $ZYPPERSTATE -eq 0 ]; then
                log "info" "Offline update applied successfully"
            else
                log "err" "Offline update failed"
            fi
            # Remove the trigger file
            rm $ZYPPER_OFFLINE_UPDATE_STATUS_FILE
        fi
    fi
    if [ $DOWNLOADSTATE -eq 2 ]; then
        log "info" "Download of updates failed or download was incomplete"
    fi
    if [ $DOWNLOADSTATE -eq 0 ]; then
        log "info" "Update service not running properly"
    fi
    if [ $action = "stop" ]; then
        # clean up
        rm -f $ZYPPER_OFFLINE_UPDATE_STATUS_FILE
        # stop service process and cleanup
        pid=$(cat $PIDFILE)
        rm $PIDFILE
        kill $pid
    fi
    if [ -e $INSTALL_LOG ]; then
        rm $INSTALL_LOG
    fi
    # wait for sending e-mail
    sleep 1
    # Ensure the service exits cleanly
    exit 0
fi