#!/bin/bash

if [ "$EUID" -ne 0 ]; then
  echo "Please run as root"
  exit
fi

if [ $# -gt 1 ]; then
  echo "Usage: create-systemd-service-and-timer.sh [--fast]"
  echo ""
  echo "options:"
  echo "--fast		sets the backup script, log file and directory based on the name of the service"
  echo ""
  exit 0
fi

echo "Please enter the desired name for the service (e.g., backup). Can only contain [a-z, A-Z, 0-9]: "
read SERVICE_NAME

BAKUP_SCRIPT_PATH=""
LOG_FILE_PATH=""
WORKING_DIRECTORY=""


if [ "$1" = "--fast" ]; then
  echo "Enter the name of the user where the service directory lives:"
  read USER_NAME
  BACKUP_SCRIPT_PATH="/home/$USER_NAME/$SERVICE_NAME/backup-$SERVICE_NAME.sh"
  LOG_FILE_PATH="/home/$USER_NAME/$SERVICE_NAME/backup-$SERVICE_NAME.log"
  WORKING_DIRECTORY="/home/$USER_NAME/$SERVICE_NAME"
else
  echo "Please enter the path to your backup script (e.g., /home/user/service/backup.sh): "
  read BACKUP_SCRIPT_PATH

  echo "Please enter the path to the log file for the script (e.g., /home/sem/service/backup.log): "
  read LOG_FILE_PATH

  echo "Please enter the working directory for the backup service (e.g., /home/user/service): "
  read WORKING_DIRECTORY
fi

echo "Using service name: $SERVICE_NAME"
echo "Using backup script path: $BACKUP_SCRIPT_PATH"
echo "Using log file path: $LOG_FILE_PATH"
echo "Using service working directory: $WORKING_DIRECTORY"

echo "Please enter the desired OnCalendar time for the timer (e.g.'Mon *-*-* 02:00:00'): "
read ONCALENDAR_TIME

echo "Please enter a description for the interval of the timer (e.g., 'Monday at 02:00'): "
read TIMER_DESCRIPTION

SERVICE_FILE="/etc/systemd/system/backup-${SERVICE_NAME}.service"
TIMER_FILE="/etc/systemd/system/backup-${SERVICE_NAME}.timer"

cat > $SERVICE_FILE <<EOL
[Unit]
Description=Backup $SERVICE_NAME to the backups VM

[Service]
Type=oneshot
ExecStart=$BACKUP_SCRIPT_PATH > $LOG_FILE_PATH
User=sem
WorkingDirectory=$WORKING_DIRECTORY
EOL

echo "Created service file at $SERVICE_FILE"

cat > $TIMER_FILE <<EOL
[Unit]
Description=Backup $SERVICE_NAME every $TIMER_DESCRIPTION

[Timer]
OnCalendar=$ONCALENDAR_TIME
Persistent=true

[Install]
WantedBy=timers.target
EOL

echo "Created timer file at $TIMER_FILE"

systemctl daemon-reload
systemctl enable backup-${SERVICE_NAME}.timer
systemctl start backup-${SERVICE_NAME}.timer

systemctl list-timers