#!/bin/sh

linuxpkgnames=""

[ -z "$TMPDIR" ] && TMPDIR=/tmp

lock_file="$TMPDIR/sysupdate.lock"

get_running_programs()
{
  echo "$*" | tr '-' '_' | grep -qwE "$(echo "$linuxpkgnames" | tr '-' '_')"  && echo linux
  for I in $*
  do
    pgrep -xi "$I" >/dev/null && echo $I
  done
}

stop()
{
  rm "$lock_file"
  exit $1
}

fetch_error()
{
  echo "Error: Could not fetch packages" >&2
  znotif -T "System updates" -t 120 -m "Error during system updates: could not fetch packages"
  stop 3
}

update_error()
{
  echo "Error: Could not upgrade system" >&2
  znotif -T "System updates" -t 120 -m "Error during system updates: could not upgrade"
  stop 3
}

which zupdate >/dev/null 2>&1 || { echo "zupdate not installed" >&2; exit 4; }
which znotif >/dev/null 2>&1 || { echo "znotif not installed" >&2; exit 4; }

# Check if another process is running
if [ -n "$(pgrep zupdate)" ] || [ -f "$lock_file" ]
then
  echo "Updates are already running" >&2
  exit 1
fi
touch "$lock_file"

# package manager specific variables
if which apt >/dev/null 2>&1
then
  linuxpkgnames="linux-image-.*"
elif which pacman > /dev/null 2>&1
then
  linuxpkgnames="linux|linux-hardened|linux-lts|linux-zen|linux-mainline|linux-rt|linux-git|linux-next"
else
  echo "Unsupported package manager" >&2
  stop 2
fi

#fetch updates

all=$(zupdate -MkdL) || fetch_error
size=$(echo "$all" | head -n1)
packages=$(echo "$all" | cut -d' ' -f1 | tail -n+2)

if [ -z "$packages" ]
then
  echo "No updates"
  stop 0
fi

# find running updates
running_programs=$(get_running_programs "$packages")
if [ -n "$running_programs" ]
then
  if ! znotif -T "System Updates" -y -m "The following running programs have recieved updates: \n$(echo "$running_programs" | sed 's|^|  -  |g')\nProceed?"
  then
    echo "Update cancelled" >&2
    stop 5
  fi
fi

znotif -T "System Updates" -t 10 -m "Installing updates for $size download"
#update
zupdate -yu || update_error
#end update
znotif -T "System Updates" -t 5 -m "Updates finished"

stop 0