#!/bin/bash
#
#  $Id:$
#
# Shell script to convert Fahrenheit to Celsius Temperature or Celsius
# to Fahrenheit Temperature
# -------------------------------------------------------------------------
# Copyright (c) 2005 nixCraft project <http://cyberciti.biz/fb/>
# This script is licensed under GNU GPL version 2.0 or above
# -------------------------------------------------------------------------
# This script is part of nixCraft shell script collection (NSSC)
# Visit http://bash.cyberciti.biz/ for more information.
# -------------------------------------------------------------------------
# Fahrenheit and Celsius Temperature Scales more info:
# http://en.wikipedia.org/wiki/Temperature_conversion_formulas
# --------------------------------------------------------------------


function convert_c2f
{
    echo -n "Enter temperature (C) : "
    read tc
    # formula Tf=(9/5)*Tc+32
    tf=$(echo "scale=20; ((9/5) * $tc) + 32" | bc)
    printf "\n%0.2f degrees C = %0.2f degrees F\n\n" $tc $tf
}

function convert_f2c
{
    echo -n "Enter temperature (F) : "
    read tf
    # formula Tc=(5/9)*(Tf-32)
    tc=$(echo "scale=20; (5/9) * ($tf - 32)" | bc)
    printf "\n%0.2f degrees F = %0.2f degrees C\n\n" $tf $tc
}

function display_menu
{
    echo
    echo "*** Converting between the different temperature scales ***"
    echo "  1. Convert Celsius temperature into Fahrenheit"
    echo "  2. Convert Fahrenheit temperatures into Celsius"
    echo "  3. Quit the program"
    echo
    echo -ne "Select your choice (1, 2 or 3) : "
}

function quit_program
{
    echo "Finished."
    echo
    exit 0
}

while : ;
do
        display_menu

        read choice
        echo

        case $choice in
                1)      convert_c2f
                        continue ;;
                2)      convert_f2c
                        continue ;;
                3)      quit_program
                        break ;;
                *)      echo "Please select 1, 2 or 3 only"
                        echo
                        echo -e "** Error: '$choice' is not valid.\n" ; continue ;;
        esac
done

# End of File