#!/bin/bash

#initiate continueCalculator variable to 1
continueCalculator=1

#start loop for calculator
while [ $continueCalculator = 1 ]
do
#ask user for first number
echo "Please enter the first value "
#get value
read firstNumber
#ask user for second number
echo "Please enter the second value "
#get value
read secondNumber
#ask user what operation they want to use and list all 4 options
echo "Which operation would you like to use? Enter 1,2,3 or 4."
echo 1 "1 for addition"
echo 2 "2 for subtraction"
echo 3 "3 for multiplication"
echo 4 "4 for division"
# get operation from user
read operation
#go through case until you reach operation needed
case $operation in
  # calculate for addition
  1)answer=$(($firstNumber + $secondNumber))
    #output answer
    echo "You entered $firstNumber and $secondNumber. The sum is: $answer";;
  
  # calculate for subtraction
  2)answer=$(($firstNumber - $secondNumber))
    #output answer
    echo "You entered $firstNumber and $secondNumber. The difference is: $answer";;
  
  # calculate for multiplication
  3)answer=$(($firstNumber * $secondNumber))
    #output answer
    echo "You entered $firstNumber and $secondNumber. The product is: $answer";;
  
  # is the denominator 0?
  4)if (($secondNumber == 0)); then
      echo "You entered $firstNumber and $secondNumber. You cannot divide by 0";
    else
      # denominator not 0. calculate for division
      answer=$(($firstNumber / $secondNumber))
      # calculate remainder
      remainder=$(($firstNumber % $secondNumber))
      #output answer
      echo "You entered $firstNumber and $secondNumber. The quotient is: $answer with a remainder of $remainder";
    fi
esac
# continue loop while continue == yes
echo "Press 1 to continue, press 0 to stop"
# get answer if user wants to continue
read continueCalculator
# did user enter 0?
if (($continueCalculator == 0)); 
#exit the loop
then
  exit
fi
done