#!/bin/sh -u
# DAT2330 03W Unix Final - Wednesday Script Sample Solution
#  $0  [ file ]
# -IAN!  idallen@ncf.ca

# Step 1 - 2 marks - correct header (interpreter, PATH, and umask)
# Set a standard search path and non-restrictive umask.
#
export PATH=/bin:/usr/bin
umask 022

# Step 2 - 7 marks
# Exit the script if more than one argument is given.
#
if [ $# -gt 1 ]; then
	echo 1>&2 "$0: expecting one optional pathname, found $# ($*)"
	exit 1
fi

# Step 3 - 4 marks
# Use the Unix password file if no arguments are given.
#
if [ $# -eq 0 ]; then
	fpath='/etc/passwd'
else
	fpath="$1"
fi

# Make sure the pathname is not empty, is a file, and is readable.

# Step 4 - 6 marks
#
if [ ! -s "$fpath" ]; then
	echo 1>&2 "$0: pathname '$fpath' is missing or empty"
	exit 2
fi

# Step 5 - 6 marks
#
if [ ! -f "$fpath" ]; then
	echo 1>&2 "$0: pathname '$fpath' is not a plain file"
	exit 3
fi

# Step 6 - 6 marks
#
if [ ! -r "$fpath" ]; then
	echo 1>&2 "$0: file '$fpath' is not readable"
	exit 4
fi

# Step 7 - 3 marks
# Count the characters in the file.
#
numchar=$( wc -c <"$fpath" )

# Make sure that a file named with your Algonquin userid exists.
# Append the count of characters in the $fpath to the $outfile file.

# Step 8 - 7 marks
outfile="$USER" # or just enter your actual abcd0123 userid
if [ ! -e "$outfile" ]; then
	echo 1>&2 "$0: Output file '$outfile' is missing from current directory"
	exit 5
fi

# Step 9 - 3 marks
#
echo "Input file '$fpath' contains $numchar characters" >>"$outfile"

# Prompt and read a size limit.
# Exit the script if the user enters nothing.

# Step 10 - 3 marks
#
echo 1>&2 "Enter a numeric size limit:"
read numin || exit 1

# Step 11 - 6 marks
#
if [ -z "$numin" ] ; then
	echo 1>&2 "$0: empty input count - nothing done"
	exit 6
fi

# Step 12 - 7 marks
# Issue a message if the limit is >= character count of the file.
#
if [ "$numin" -ge "$numchar" ] ; then
	echo "Input number $numin is >= $numchar characters in file '$fpath'"
	exit 7
fi