#!/bin/bash

function helpexit() {
    echo "Display extension sizes and counts"
    echo "Returns only the size as number"
    echo "  --help   This help"
    echo "  -a       Disable animation while counting"
    exit
}
function filesize() {
# Return a human readable size from integer of bytes
# Usage:  filesize 10000

    [ "$1"  = "0" ] && {
        echo "0~B"
        return 0
    }

    awk 'BEGIN{ x = '$1'
        split("B kB MB GB TB PB EB ZB", type)
        for(i=7;y < 1;i--)
            y = x / (2^(10*i))
        if (i==-1) { printf( "%d~B", x) }
        if (i>-1) { printf( "%0.1f%s", y, type[i+2]) }
    }' || return $?
}
function siprefix() {
# Return a SI prefixed string from integer

    [ "$1"  = "0" ] && {
        echo "0~#"
        return 0
    }

    awk 'BEGIN{ x = '$1'
        split("# k# M# G# T# P# E# Z#",type)
        for(i=7;y < 1;i--)
            y = x / (10^(3*i))
        if (i==-1) { printf( "%d~#", x) }
        if (i>-1) { printf( "%0.1f%s", y, type[i+2]) }
    }' || return $?
}

function animate() {
  CHARS=( \
    '\_(".)_/' \
    '\_(.")_/' \
    '\_(".)_/' \
    '\_(.")_/' \
    "\_('')_/" \
    '\_(..)_/' \
    "\_('')_/" \
    "\_('')_/" \
  )
  i=0
  while true; do
    sleep 1.5
    printf "\r %s\r" "${CHARS[$i]}" >&2
    i=$(( (i + 1)%${#CHARS[@]} ))
  done
}

function processfolders() {

  printf "%8s %8s %-10s\n" \
    Size \
    Count \
    Name

  find "$@" -type f \
  -printf "%s|%P\n" 2>/dev/null | awk '
  BEGIN { FS = "|" }
  {
    n = split($2, fname, "/");
    if (index(fname[n], ".") > 1) {
      n = split(fname[n], fsplit, ".");
      ext = "."tolower(fsplit[n])
    } else {
      ext = "N/A"
    }
    sum[ext] += $1;
    count[ext] += 1;
  }
  END {
    for (e in sum) {
      print sum[e]"|"count[e]"|"e
    }
  }' | sort -n -k 1 -t\| | while read line; do
   IFS='|' read -r -a array <<< "$line"

   printf "%8s %8s %-10s\n" \
    $( filesize "${array[0]}" ) \
    $( siprefix "${array[1]}" ) \
    "${array[2]}"
  done | sed -e 's,~B, B,' -e 's,~#, #,'

}

# Get options
what=()
ANIMATE=1
for (( i=1; i<=$#; i++ )); do
  [[ "${!i}" = "--help" ]] && helpexit
  [[ "${!i}" = "-"* ]] && {
    [[ "${!i}" =~ -.*a ]] && { ANIMATE=0; }
    [[ "${!i}" =~ -.*h ]] && { helpexit; }
    continue
  }
  what+=( "${!i}" )
done

[[ -z "${what[@]}" ]] && what="."

if [[ "$ANIMATE" -eq 1 ]]; then
  trap 'trap - SIGTERM && kill -- -$$' EXIT SIGINT SIGTERM
  animate &
fi

processfolders "${what[@]}"

if [[ "$ANIMATE" -eq 1 ]]; then
  trap - EXIT SIGINT SIGTERM
  kill %1
fi