showing file thumbnails in terminology

lsthumb.sh

#!/bin/sh

WIDTH=6
HEIGHT=3
CHAR="."

if [ -z "$*" ]; then
   PARAM="./*"
else
   PARAM=$*
fi

function get_info {
   local ORIG_STTY="$(stty -g)"
   stty -echo
   echo -ne "\e}qs\0"
   read RESPONSE
   stty "$ORIG_STTY"

   TERM_WIDTH="$(echo "$RESPONSE" | cut -d';' -f1)"
   TERM_HEIGHT="$(echo "$RESPONSE" | cut -d';' -f2)"
}

function print_block {
   echo -ne "\e}ib\0"
   for (( c = 0 ; c < $WIDTH ; c++ )); do
      echo -n "$CHAR"
   done
   echo -ne "\e}ie\0"
}

# $1 = path
function declare_inline_media {
   echo -ne "\e}it$CHAR$WIDTH;$HEIGHT;$1\0"
}

# $1 = amount
function move_left {
   echo -ne "\e[${1}D"
}

# $1 = amount
function move_right {
   echo -ne "\e[${1}C"
}

# $1 = amount
function move_up {
   echo -ne "\e[${1}A"
}

# $1 = amount
function move_down {
   echo -ne "\e[${1}B"
}

get_info

COL=1
for FILENAME in $PARAM; do
   ABSPATH="$(realpath "$FILENAME")"

   if [ -d "$ABSPATH" ]; then
      THUMB="folder"
   else
      BASENAME="$(basename "$ABSPATH")"
      EXT="${BASENAME##*.}"
      case "$EXT" in
         jpg|jpeg|png|gif|bmp|tif|ico|svg|pdf)
            THUMB="$ABSPATH";;

         *) THUMB="empty";;
      esac
   fi

   declare_inline_media "$THUMB"

   for (( ROW = 0 ; ROW < $HEIGHT ; ROW++ )); do
      print_block
      move_left $WIDTH
      move_down 1
   done

   COL=$(( $COL + $WIDTH + 2 ));

   if [ $COL -ge $TERM_WIDTH ]; then
      COL=1
      echo
   else
      move_right $(( $WIDTH + 1))
      move_up $HEIGHT
   fi

done

for (( ROW = 0 ; ROW < $HEIGHT ; ROW++)); do echo; done