#!/bin/bash

function usage ()
{
  printf "Usage: %s <threshold> <filename>\n" $( basename $0 )
}

function check_args ()
{
  #remember $1 is the first arg sent to function
  #$2 is second (filename)
  if (( $1 < 0 || $1 > 100 )) 
  then 
   echo "Out of range"; 
   usage; 
   exit 1;
  fi
  echo $2
  if [ ! -f "$2" ] 
  then  
   echo "Invalid file"; usage; exit 1; 
  fi
}

#dont echo anything else out in this function
function check_space ()
{
 threshold=$1
 machine=$2 
 cmd="df -h | egrep '/$' | awk {' print \$5 '} | sed 's/%//'"
 #echo $cmd
 current_usage=$(ssh $machine "$cmd")
 #echo "curr: $current_usage, thresh: $threshold"
 if (( $current_usage > $threshold ))
 then
   echo True
 else
   echo False
 fi
}

threshold=$1
filename=$2

check_args $threshold $filename

for machine in $(cat $filename)
do
  #theoretically we would ssh to each of the machines to check if they are over threshold, but I did not.
  over_threshold=$(check_space "$threshold" "$machine")
  #check_space "$threshold" "$machine"
  if [ "$over_threshold" == "True" ]
  then
    echo "We need to clean things up"
    #run_updates
    # I didn't write this function. It would essentially just do apt update and autoclean
  else
    echo "you are below the threshold, good job"
  fi 
done