#!/bin/sh

ip_of_shm2_0="0.0.0.0"

if [ $ip_of_shm2_0 = "0.0.0.0" ]; then
  echo "ERROR, please correct the IP-adress to your smartmeter-ip."
  echo 'Example: ip_of_shm2_0="192.168.178.44"'
  echo "Please dont forget to set the IP-address to a static address in your router."
  echo "If the IP changes, the script will fail and restart shm-et340 every 15 seconds."
  exit 1
fi

# Set a flag variable to track whether the service has been started
service_started=false
# Wait for 25 seconds or else the VRM Portal will stop working. The shm-et340 has to be started after the mqtt broker. 
sleep 25
check_status() {
  pid=$(pidof /data/drivers/shm-et340/shm-et340)
  if [ -n "$pid" ]; then
      wait "$pid"
      exit_status=$?
      if [ "$exit_status" -ne 0 ]; then
          # Restart the "shm-et340" process if it has crashed or exited with an error.
          setsid /data/drivers/shm-et340/shm-et340 > /dev/null 2>/dev/null &
      fi
      # Set the flag variable to true to indicate that the service has been started
      service_started=true
  else
      # Set the flag variable to false to indicate that the service has been stopped
      service_started=false
  fi
}
start_service() {
  # Start the "shm-et340" process if it is not already running and the service has not been started
  if ! pidof /data/drivers/shm-et340/shm-et340 > /dev/null && ! $service_started; then
      setsid /data/drivers/shm-et340/shm-et340 > /dev/null 2>/dev/null &
      # Set the flag variable to true to indicate that the service has been started
      service_started=true
  fi
}
stop_service() {
  # Kill the "shm-et340" process if it is running
  if pidof /data/drivers/shm-et340/shm-et340 > /dev/null; then
      kill $(pidof /data/drivers/shm-et340/shm-et340)
      # Set the flag variable to false to indicate that the service has been stopped
      service_started=false
  fi
}
# Enter an infinite loop
while true; do
 if ping -c 3 -W 5 $ip_of_shm2_0 > /dev/null; then # Only check process if smartmeter is online
     echo Smartmeter IP $ip_of_shm2_0 reachable.
     check_status # Check if process is running
  else
    echo Smartmeter IP $ip_of_shm2_0 offline. Restarting shm-et340 service.
    stop_service
  fi
    start_service
  # Wait for 15 seconds before checking the status again
  sleep 15
done