#!/bin/bash
# I, Ian Kelling, follow the GNU license recommendations at
# https://www.gnu.org/licenses/license-recommendations.en.html. They
# recommend that small programs, < 300 lines, be licensed under the
# Apache License 2.0. This file contains or is part of one or more small
# programs. If a small program grows beyond 300 lines, I plan to switch
# its license to GPL.

# Copyright 2024 Ian Kelling

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at

#     http://www.apache.org/licenses/LICENSE-2.0

# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.


# Get screenshots from bow, discard them if they dont change much.

[[ $EUID == 0 ]] || exec sudo -E "${BASH_SOURCE[0]}" "$@"

set -e; . /usr/local/lib/bash-bear; set +e

dest_dir=/d/ziva-log
case $HOSTNAME in
  sy)
    dest_dir=/t/zlog
    ;;
esac

f=/run/user/1000/ziva-tmp.jpg

install -g 1000 -o 1000 -m 700 $dest_dir
cd $dest_dir
shopt -s nullglob
jpgs=( 20*jpg )
if (( ${#jpgs[@]} >= 1 )); then
  # shellcheck disable=SC2012 # this is much sorter than find|sort
  lastf=$(ls -1 20*jpg  | tail -n1)
fi

ssh bow DISPLAY=:0 scrot -z $f 2>/dev/null || exit 0
rsync --inplace bow:$f $dest_dir 2>/dev/null || exit 0
ssh bow rm -f $f

same=false
if [[ $lastf ]]; then
  # returns 2 on error, but maybe in that case we want to ignore, file the image away
  # and then it can go away in a subsequent comparison. going with that for now.
  diff=$(compare -metric MSE $lastf ziva-tmp.jpg /dev/null |& sed 's/[^0-9].*//') ||:
  if printf "%s\n" "$diff" | grep -E '^[0-9]+$' &>/dev/null && (( diff < 200 )); then
    same=true
  fi
fi

if $same; then
  rm -f ziva-tmp.jpg
else
  mv ziva-tmp.jpg "$(date +%F.%R)".jpg
fi