#!/bin/bash
#
# Author: Georg Voell - georg.voell@standby.cloud
# Version: @(#)cloud-agent 3.2.0 25.09.2025 (c)2025 Standby.cloud
# Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl/
#
#@  Show infos about installed oracle cloud agent and restart and renew it if sprecified
#
# Exit codes:
#  01: Unsupported platform.
#  02: No root privileges (needed to proceed).
#  03: Needed tool missing in in PATH.
#  04: Unknown parameter.
#
# Update history:
#
# V 3.2.0 23.09.2025 New version
#
# Usage:
#
#  cloud-agent			# Shows infos about oracle cloud agent rpm
#  cloud-agent status	# Shows infos if oracle cloud agent is running or not
#  cloud-agent restart	# Restart oracle cloud agent
#  cloud-agent renew	# Delete old version and install new oracle cloud agent rpm
#

# Set some defaults
exitcode=0													# Return code of the script
package="oracle-cloud-agent"								# RPM package name
script=`echo "$0" | sed 's|^[-]*||'`						# Name of this script without any leading dashes
progstr=`basename "$script"`								# Just the name of the script
pid="$$"													# Get the process id from current shell
tmpdir="/tmp"												# Temporary directory
timestamp=`date '+%y%m%d%H%M%S'`							# Extension String with current date and time
scratchfile="${tmpdir}/${progstr}.${timestamp}.${pid}.tmp"	# Temporary file

# Get current user and os
ME=`whoami`										# Current user
OS=`uname -s`									# Infos about the host os (e.g. Darwin, SunOS, Linux)
PARAM=`echo "$1" | tr '[:upper:]' '[:lower:]'`	# First papameter

# Set PATH
PATH="/bin:/.local/bin:/usr/local/bin:$PATH"

# Check for some tools
yum=`which "yum" 2>/dev/null | sed 's|^no yum in .*||'`
rpm=`which "rpm" 2>/dev/null | sed 's|^no rpm in .*||'`
systemctl=`which "systemctl" 2>/dev/null | sed 's|^no systemctl in .*||'`

# Delete file
function DeleteFile {
	local filename=${1}
	
	if [ "$filename" != "" ]; then
		if [ -f "$filename" ]; then
			rm -f "$filename"
		fi
	fi
}

# Delete tempfiles
function Cleanup {
	DeleteFile $scratchfile
}

# Kill the old agent the hard way ('systemctl stop oracle-cloud-agent' may not work here)
function KillAgent {
	sleep 10
	pid=`ps -ef | grep ${package}/agent | grep -v grep | head -n 1 | awk '{print $2}'`
	if [ "$pid" != "" ]; then
		kill -9 $pid
	fi
}

# Main
if [ "$OS" != "Linux" ]; then
	echo "Unsupported platform '$OS'. Exiting."
	exitcode=1
else
	# Check if we have root privileges
	if [ "$ME" != "root" ]; then
		echo "Need to be 'root'. Exiting."
		exitcode=2
	else
		# Check if we have curl installed
		if [ "$yum" = "" ]; then
			echo "No 'yum' in PATH. Exiting."
			exitcode=3
		else
			if [ "$PARAM" = "" ]; then
				$yum info "$package" > $scratchfile 2>/dev/null
				exitcode=$?
				
				if [ $exitcode -eq 0 -a -s $scratchfile ]; then
					cat $scratchfile | grep ' : '
				else
					echo "Not installed: '$package'. Exiting."
				fi
			else
				case "$PARAM" in
					status)
						if [ "$systemctl" != "" ]; then
							$systemctl "$PARAM" "$package" | head -n 8
						else
							exitcode=3
						fi
						;;
					restart)
						if [ "$systemctl" != "" ]; then
							$script kill_restart &
							exitcode=$?
							
							if [ $exitcode -eq 0 ]; then
								disown
								pid=`ps -ef | grep "$progstr kill_$PARAM" | grep -v grep | awk '{print $2}'`
								echo "Process ID: $pid"
							fi
						else
							exitcode=3
						fi
						;;
					do_restart | kill_restart)
						if [ "$PARAM" = "kill_restart" ]; then
							KillAgent
						fi
						
						$systemctl restart $package >/dev/null 2>&1	# systemctl status oracle-cloud-agent
						exitcode=$?
						;;
					renew)
						$script kill_renew &
						exitcode=$?
							
						if [ $exitcode -eq 0 ]; then
							disown
							pid=`ps -ef | grep "$progstr kill_$PARAM" | grep -v grep | awk '{print $2}'`
							echo "Process ID: $pid"
							# echo "Parent Prozess ID: $$"
							# echo "Sudo Prozess ID: $PPID"
						fi
						;;
					do_renew | kill_renew)
						if [ "$PARAM" = "kill_renew" ]; then
							KillAgent
						fi
						
						$yum remove -y "$package" >/dev/null 2>&1
						$yum install -y "$package" >/dev/null 2>&1
						exitcode=$?
						;;
					*)
						echo "Unknown parameter '$PARAM'. Exiting."
						exitcode=4
				esac
			fi
		fi
	fi
fi

# Cleanup and exit with exitcode
Cleanup
exit $exitcode