#!/bin/bash

# Exam 2020/09/14 - Exercise 10

# Check correct number of parameters
if [ $# -lt 1 ]; then
    echo "Usage: ./prog.sh <FILE>"
    exit 1
fi

# Read file line by line
while read line; do

    # Compute number of words in line
    n=$(echo $line | wc -w)

    # If line has an odd number of words convert it to lower case
    if [ $[$n%2] -eq 1 ]; then
        echo $line | tr [A-Z] [a-z]
    fi  

    # If line has an even number of words convert it to upper case
    if [ $[$n%2] -eq 0 ]; then
        echo $line | tr [a-z] [A-Z]
    fi  
    
done < $1

exit 0