Recreating wc in bash using IFS - Unix Shell Programming

#!/bin/bash
# Recreating wc in bash using IFS
# Unix Shell Programming, 3rd Edition - Exercise 3 from Chapter 12

lines=0
words=0
chars=0

function for_great_justice_count_every_zig () # wc function
{
  IFS_BAK=$IFS
  file_name="$1"
  l=0
  w=0
  c=0
  word=("")

  IFS=$'\n'
  while read -r line
    do
      l=$((l+1))
      curr_line_char=${#line}
      c=$((c+curr_line_char))
      # set IFS to standard field terminating chars
      IFS=$IFS_BAK
      read -a word <<< "$line"
      w=$((w+${#word[*]}))
      # set IFS to \n
      IFS=$'\n'
  done < "$file_name"

  IFS=$IFS_BAK
  # If last line is not \n term'd then last read will fail
  # We calculate the last line separately if not null.
  # Idiot test, script by Robert A. Petersen (Petersen.Mobile@Gmail.com)
  # If you steal this for your class, remove this comment and change
  # the function name at least.
  if [ -n "$line" ]
    then
      # We should not count this line, because it
      # is not term'd by newline character
      curr_line_char="${#line}"
      c=$((c+curr_line_char))
      read -a word <<< "$line"
      w=$((w+${#word[*]}))
  fi
  # The newline characters are also characters, so count them
  c=$((c+l))
  #   echo -e "\nFile name: $file_name \nLines : $l\tWords: $w\tCharacters: $c"
  echo "    How are you Gentlemen?" # Some humor
  echo "    All your wc are belong to us." # See https://www.youtube.com/watch?v=8fvTxv46ano
  echo "  $l lines, $w words, $c chars in $file_name"
  chars=$((total_c+c))
  lines=$((total_l+l))
  words=$((total_w+w))
}

# Main Sequence Turn On
file_count=$#
while [ -n "$1" ]
do
  file_name="$1"
  if [ ! -f "$file_name" ]
   then
     echo "File \"$file_name\" does not exist, someone set you up the bomb?"
     shift 1
     continue
  fi
  # Calls wc function from earlier
  for_great_justice_count_every_zig "$1"

  shift 1
done
# Apologies for 10 year old internet memes used