#!/usr/bin/bash

DIR="/home/immortaly007/screenshot-log"
FORMAT="png"
SIMILARITY_DELETE_TRESHOLD=100
HTML_THUMB_WIDTH=200
SCALE="50%"

DAY=`date +%Y-%m-%d`
TIME=`date +%H.%M.%S.%3N`
mkdir -p $DIR/$DAY
SCR_NEW="$DIR/$DAY/$TIME.$FORMAT"
SCR_LAST=`ls -t $DIR/$DAY/*.png | head -n1`

# do a screenshot
if [ "$XDG_CURRENT_DESKTOP" = "KDE" ]
then
  spectacle -bn -o $SCR_NEW
else
  import -window root $SCR_NEW
fi

#requires ImageMagick
DISTANCE=`compare -metric MAE $SCR_LAST $SCR_NEW NULL: 2>&1`
echo $DISTANCE
# ImageMagick outputs something like "21.8357 (0.218357)"; we only want to use the first number for the comparison below, so we use cut to get just that
DISTANCE=`echo $DISTANCE | cut -d " " -f1 -`


if [ "$DISTANCE" = "inf" ]
then
  DISTANCE=1000
fi

echo $DISTANCE between $SCR_LAST and $SCR_NEW
IS_SIMILAR=`echo "$DISTANCE < $SIMILARITY_DELETE_TRESHOLD" | bc`
if [ "$IS_SIMILAR" = "1" ]
then
  rm $SCR_NEW
  echo "`date`: Distance = $DISTANCE; too similar; RM $SCR_NEW"
  # echo "`date` RM" >> $DIR/$DAY/log-.log
else
  mogrify -scale $SCALE $SCR_LAST
  # Ensure that the new file is still seen as the most recent one
  FUTURE=`date +%Y%m%d%H%M.%S -d "+1 second"`
  touch -t $FUTURE  "$SCR_NEW"
#   echo "<p>`date +%H:%M:%S` <a href=\"$SCR_NEW\"><img width=\"$HTML_THUMB_WIDTH\" src=\"$SCR_NEW\" /></a> <br />$WINDOW_TITLE </p>" >> $DIR/`date +%Y-%m-%d`-$PREFIX.html
fi