#!/bin/bash
# copyright 2007 Gilbert Ashley <amigo@ibiblio.org>
# BashTrix wc is an implementation of the 'wc' command
# written in pure shell. Most wc options are supported.
VERSION=0.2

# show program usage
show_usage() {
echo
echo "Usage: ${0##/*} [OPTION]... [FILE]..."
echo "${0##/} -[m|w|l|L] FILE"
echo "  or: (cat|echo) | ${0##/*} [OPTION]... "
echo "Print newline, word, and byte counts for each FILE"
echo "and a total line if more than one FILE is specified."
# echo "With no FILE, or when FILE is - read standard input." #conflicts
echo "  -m, --chars            print the character counts"
echo "  -l, --lines            print the newline counts"
echo "  -L, --max-line-length  print the length of the longest line"
echo "  -w, --words            print the word counts"
echo "      --help     display this help and exit"
echo "      --version  output version information and exit"
exit
}
show_version() {
echo ${0##/*}" (BashTrix) $VERSION"
echo "Copyright 2007 Gilbert Ashley <amigo@ibiblio.org>"
echo "This is free software written in pure POSIX shell."
exit
}

# Minimum number of arguments needed by this program
MINARGS=1
# show usage if '-h' or  '--help' is the first argument or no argument is given
case $1 in
	""|"-h"|"--help") show_usage ;;
	"--version") show_version ;;
esac
# get the number of command-line arguments given
ARGC=$#
# check to make sure enough arguments were given or exit
if [[ $ARGC -lt $MINARGS ]] ; then
 echo "Too few arguments given (Minimum:$MINARGS)"
 echo
 show_usage
fi

for WORD in "$@" ; do
	case $WORD in
		-*)  true ;
			case $WORD in
				-m) COUNT_CHARS=1 ; shift ;;
				-w) COUNT_WORDS=1 ; shift ;;
				-l) COUNT_LINES=1 ; shift ;;
				-L) MAX_LINE_LENGTH=1 ; shift ;;
				--help) show_usage ;;
				--version) show_version ;;
				# -) READ_STDIN=1 ; shift ;;
				-*) echo "Unrecognized argument" ; show_usage ;;
			esac
		;;
	esac
done

# function _freq counts the number of matches
# of PATTERN in PARSESTRING and returns FREQ
# example usage: _freq $PATTERN $PARSESTRING
function _freq() { FREQ=0
! [[ $PATTERN ]] && PATTERN=$1
! [[ $PARSESTRING ]] && PARSESTRING=$2
while [[ $PARSESTRING != "" ]] ; do
	case $PARSESTRING in
		*$PATTERN*) (( FREQ++ )) ;
			PARSESTRING=${PARSESTRING#*${PATTERN}} ;;
		*) PARSESTRING="" ;;
	esac
done
echo $FREQ
}

# convert tabs to spaces
function uniform_white() {
while read GAGA ; do
 echo $GAGA
done
}

# function _line_word_count counts the words in a line
function _line_word_count() { LINE_WORD_COUNT=0
# turn all TABS into single spaces
STRING=$(echo $1 | uniform_white)
# strip off leading spaces
SEP=" "
while [[ ${STRING:0:1} = $SEP ]] ; do
 STRING=${STRING:1}
done
# strip trailing spaces
OFFSET=$(( ${#STRING} - 1 ))
while [[ ${STRING:$OFFSET:1} = $SEP ]] ; do
 # remove one CHAR from the STRING
 STRING=${STRING:0:$OFFSET}
 # decrement the OFFSET by one for the removed character
 (( OFFSET-- ))
done
PARSESTRING=$STRING
# count the number of spaces
_freq " " $PARSESTRING 1> /dev/null
# the number of words is spaces +1 except for blank lines
if [[ "$STRING" != "" ]] ; then
 LINE_WORD_COUNT=$(( $FREQ + 1 ))
fi
}

# function _line_char_count counts the characters in a line UNUSED
function _line_char_count() { LINE_CHAR_COUNT=0
#PARSESTRING=$(echo $1 | uniform_white)
PARSESTRING="$1"
while [[ $PARSESTRING != "" ]] ; do
	# read one character
	FC=${PARSESTRING:0:1}
	# advance the poiter one character
	PARSESTRING=${PARSESTRING:1}
	(( LINE_CHAR_COUNT++ ))
done
# add an extra character for the end of line CHAR
(( LINE_CHAR_COUNT++ ))
}

if [[ $# -gt 0 ]] ; then
	FILE_COUNT=0
	TOTAL_LINE_COUNT=0
	TOTAL_WORD_COUNT=0
	TOTAL_CHAR_COUNT=0
	TOTAL_LONGEST_LINE=0
	while [[ $# -gt 0 ]] ; do
		# count number of input files
		(( FILE_COUNT++ ))
		FILE_NAME="$1"
		if [ ! -r "$1" ] ; then
			echo "Cannot find file $1" 1>&2
			exit 1
		else
			FILE_LINE_COUNT=0
			FILE_WORD_COUNT=0
			FILE_CHAR_COUNT=0
			FILE_LONGEST_LINE=0
			LINE=
			IFS=
			while read LINE ; do
			  # add the curent line to the line counter
			  (( FILE_LINE_COUNT++ ))
			  # capture the text of the line
			  STRING="$LINE"
			  # count the words in this line
			  if [[ $COUNT_WORDS ]] ; then
			    _line_word_count $STRING
			    FILE_WORD_COUNT=$(( $FILE_WORD_COUNT + $LINE_WORD_COUNT ))
			  fi
			  # count the characters in this line
			  if [[ $COUNT_CHARS ]] ; then
			    LINE_CHAR_COUNT=$(( ${#LINE} + 1 ))
			    FILE_CHAR_COUNT=$(( $FILE_CHAR_COUNT + $LINE_CHAR_COUNT ))
			  fi
			  if [[ $MAX_LINE_LENGTH ]] ; then
				LINE_CHAR_COUNT=$(( ${#LINE} ))
				if [[ $LINE_CHAR_COUNT -gt $FILE_LONGEST_LINE ]] ; then
					FILE_LONGEST_LINE=$LINE_CHAR_COUNT
				fi
			  fi
			# go to next LINE
			done <"$1"
			TOTAL_LINE_COUNT=$((TOTAL_LINE_COUNT + $FILE_LINE_COUNT))
			TOTAL_WORD_COUNT=$(( $TOTAL_WORD_COUNT + $FILE_WORD_COUNT ))
			TOTAL_CHAR_COUNT=$(( $TOTAL_CHAR_COUNT + $FILE_CHAR_COUNT ))
		fi
		
		if [[ $FILE_LONGEST_LINE -gt  $TOTAL_LONGEST_LINE ]] ; then
				TOTAL_LONGEST_LINE=$FILE_LONGEST_LINE
		fi
		
		FILE_OUTPUT="$(echo $FILE_LINE_COUNT $FILE_WORD_COUNT $FILE_CHAR_COUNT \
				$FILE_LONGEST_LINE $FILE_NAME | uniform_white)"
		echo $FILE_OUTPUT
	# go to next FILE in $@
	shift
	done
	
	# detect multiple input files so the totals can be shown
	if [[ $FILE_COUNT -gt 1 ]] ; then
	 TOTAL_OUTPUT="$(echo $TOTAL_LINE_COUNT $TOTAL_WORD_COUNT $TOTAL_CHAR_COUNT \
			$TOTAL_LONGEST_LINE total | uniform_white)"
	 echo $TOTAL_OUTPUT
	fi
	exit
else
	# accept piped-in input only if "$@" is empty  ( $#=0 )
	# elif [[ $READ_STDIN ]] would enforce the POSIX
	# piped input is presumed to be separated into lines already
	FILE_LINE_COUNT=0
	FILE_WORD_COUNT=0
	FILE_CHAR_COUNT=0
	FILE_LONGEST_LINE=0
	IFS=
	while read LINE ; do
		# capture the text of the line
		STRING="$LINE"
		#increment the line counter
		(( FILE_LINE_COUNT++ ))
		# count hte words in a line
		if [[ $COUNT_WORDS ]] ; then
			_line_word_count $STRING
			TOTAL_WORD_COUNT=$(( $TOTAL_WORD_COUNT + $LINE_WORD_COUNT ))
		fi
		# count the characters in a line
		if [[ $COUNT_CHARS ]] ; then
			LINE_CHAR_COUNT=$(( ${#LINE} +1 ))
			TOTAL_CHAR_COUNT=$(( $TOTAL_CHAR_COUNT + $LINE_CHAR_COUNT ))
		fi
		# find the length of the longest line
		if [[ $MAX_LINE_LENGTH ]] ; then
			LINE_CHAR_COUNT=$(( ${#LINE} ))
			if [[ $LINE_CHAR_COUNT -gt $FILE_LONGEST_LINE ]] ; then
				FILE_LONGEST_LINE=$LINE_CHAR_COUNT
			fi
		fi
		# go to the next LINE
		shift
	done
	TOTAL_LINE_COUNT=$((TOTAL_LINE_COUNT + $FILE_LINE_COUNT))
	TOTAL_WORD_COUNT=$(( $TOTAL_WORD_COUNT + $FILE_WORD_COUNT ))
	TOTAL_CHAR_COUNT=$(( $TOTAL_CHAR_COUNT + $FILE_CHAR_COUNT ))
	TOTAL_LONGEST_LINE=$FILE_LONGEST_LINE
	SHOW_TOTALS=1
	shift
	# printf "%-5s %-20s %s\n" "hello" "you" there
	TOTAL_OUTPUT="$(echo $TOTAL_LINE_COUNT $TOTAL_WORD_COUNT $TOTAL_CHAR_COUNT \
			$TOTAL_LONGEST_LINE total | uniform_white)"
	TOTAL_OUTPUT="$(printf "%s %-2s %-2s %-2s %s\n" $TOTAL_LINE_COUNT $TOTAL_WORD_COUNT \
		$TOTAL_CHAR_COUNT $TOTAL_LONGEST_LINE total)"
	
	echo $TOTAL_OUTPUT
	exit
fi

exit $ERROR