# This function calculates the square of a given number
def calculate_square(num): # Function definition with one parameter
    """
    Calculates the square of a given number.
    
    Parameters:
        num (int or float): The number to be squared.
        
    Returns:
        int or float: The square of the given number.
    """
    return num ** 2 # Returns the square of the given number

# This script calculates the square of a given number
# It takes in a number as an argument and prints the square of that number

# The first line is a shebang, which specifies the interpreter to be used to run the script
#!/bin/bash

# The next line is a comment, which explains the purpose of the script
# This script calculates the square of a given number

# The next line is a variable declaration, which stores the first argument passed to the script
# The variable is named "num" and it will hold the number whose square is to be calculated
num=$1

# The next line is a conditional statement, which checks if the variable "num" is empty
# If it is empty, the script will exit with an error message
if [ -z "$num" ]; then
  echo "Please provide a number as an argument"
  exit 1
fi

# The next line is a command substitution, which executes the command within the parentheses and stores the output in the variable "square"
# The command within the parentheses is a python script that calculates the square of the number stored in the variable "num"
square=$(python calculate_square.py $num)

# The next line is a print statement, which prints the square of the number
echo $square

# Import the argparse library
import argparse

# Create an ArgumentParser object
parser = argparse.ArgumentParser()

# Add a positional argument "num" with type int
parser.add_argument("num", type=int)

# Add an optional argument "-v" or "--verbose" with action "count"
# This will count the number of times the argument is used
parser.add_argument("-v", "--verbose", action="count")

# Parse the arguments and store them in the "args" variable
args = parser.parse_args()

# Check if the "verbose" argument was used at least twice
if args.verbose >= 2:
    # If yes, print the square of the number using the calculate_square function
    print(f"The square of {args.num} is {calculate_square(args.num)}.")
# If the "verbose" argument was used only once
elif args.verbose == 1:
    # Print the number and its square using the calculate_square function
    print(f"{args.num}^2 == {calculate_square(args.num)}")
# If the "verbose" argument was not used at all
else:
    # Simply print the square of the number using the calculate_square function
    print(calculate_square(args.num))

#!/bin/bash

# This script calculates the square of a given number and allows for different levels of verbosity.

# Define the usage message for the script.
usage() {
  echo "Usage: $0 [-h] [--verbose {0,1,2}] num"
  echo "  -h, --help     show this help message and exit"
  echo "  --verbose {0,1,2}     increase output verbosity (default: 0)"
}

# Set default values for the optional arguments.
verbose=0

# Use the getopts function to parse the command line arguments.
# The colon after v indicates that the option requires an argument.
while getopts ":hv:" opt; do
  case ${opt} in
    h ) # If the help option is used, print the usage message and exit.
      usage
      exit 0
      ;;
    v ) # If the verbose option is used, set the verbose level to the argument provided.
      verbose=$OPTARG
      ;;
    \? ) # If an invalid option is used, print the usage message and exit with an error.
      echo "Invalid option: -$OPTARG" 1>&2
      usage
      exit 1
      ;;
  esac
done

# Shift the command line arguments so that the positional argument is now $1.
shift $((OPTIND -1))

# Check if the positional argument is provided.
if [ -z "$1" ]; then
  echo "Missing argument: num" 1>&2
  usage
  exit 1
fi

# Calculate the square of the given number.
square=$(( $1 * $1 ))

# Print the result based on the verbose level.
case $verbose in
  0 ) # If the verbose level is 0, only print the result.
    echo $square
    ;;
  1 ) # If the verbose level is 1, print the result and a message indicating the verbosity level.
    echo "The square of $1 is $square."
    ;;
  2 ) # If the verbose level is 2, print the result, a message indicating the verbosity level, and the original number.
    echo "The square of $1 is $square. (Verbose level: $verbose, Original number: $1)"
    ;;
esac

# Example usage:
# $ bash calculate_square.sh 5
# 25
# $ bash calculate_square.sh -v 1 5
# The square of 5 is 25.
# $ bash calculate_square.sh -v 2 5
# The square of 5 is 25. (Verbose level: 2, Original number: 5)