#!/bin/sh -u
# Test #3 answer - Script Section - 68 marks - 10 of 20%
# One line description:
#   compare number of lines in file to given number and output message
# Syntax:   $0 number [ message_string [ file_name ] ]

# Step 1 - 9-part DAT2330 format from script_style.txt - 5 marks
PATH=/bin:/usr/bin ; export PATH
umask 022

# Step 2 - 9 marks
if [ $# -lt 1 -o $# -gt 3 ]; then
    echo 1>&2 "$0: Expecting number, message, and file name;"
    echo 1>&2 "    found $# args ($*)"
    exit 2
fi

# Step 3 - 2 marks
basenum="$1"

# Step 4 - 7 marks
if [ "$basenum" -le 0 ] ; then
    echo 1>&2 "$0: basenum must be positive, found: $basenum"
    exit 3
fi

# Step 5 - 5 marks
if [ $# -ge 2 ]; then
    message="$2"
else
    message='Test File'
fi

# Step 6 - 6 marks
if [ -z "$message" ]; then
    echo 1>&2 "$0: 2nd argument (message) must not be null (empty string)"
    exit 4
fi

# Step 7 - 8 marks
if [ $# -ge 3 ]; then
    myfile="$3"
else
    echo 1>&2 "Enter file name:"
    read myfile || exit 5
fi

# Step 8 - 4 marks
myfile=$( echo "$myfile" | tr 'A-Z' 'a-z' ) || exit 6

# Step 9 - 7 marks
if [ ! -f "$myfile" ]; then
    echo 1>&2 "$0: '$myfile' is not an accessible, existing, plain file"
    exit 7
fi

# Step 10 - 3 marks
count=$( wc -l <"$myfile" )

# Step 11 - 2 marks
echo "File '$myfile' contains $count lines"

# Step 12 - 10 marks
if [ $count -gt $basenum ] ; then
    what='larger than'
elif [ $count -eq $basenum ] ; then
    what='the same size as'
else
    what='smaller than'
fi
echo "$message $myfile is $what base number $basenum"

# script exits with the exits status of the last command executed