#!/usr/bin/python

"""A Python program generating a list of prime numbers and output them into a csv file

"""

from primepackage import get_n_prime, write_primes, read_primes

def main():
    """Generate 100 prime numbers and output it into output.csv file

    """
    try:
        primes = get_n_prime(100)
    except ValueError as err:
        print('is_prime '+ err)

    try:
        write_primes(primes, 'output.csv')
    except IOError as err:
        print(err)

    try:
        prime_list = read_primes('output.csv')
    	print(prime_list)
    except IOError as err:
        print(err)

if __name__ == '__main__':
    main()
		

from primepackage.primeio import write_primes, read_primes
from primepackage.primemodule import is_prime, get_n_prime
		

"""Function for io operations

In Spring 2020, to demo how to build a Python project, this project was
created for the students in CS4900 senior seminar class. This module contains
the functions about input and output the prime nubmers into or from a csv file.

Example:
    python primeio.py

"""

__author__ = 'Lin Chen'
__version__ = 0.1
__email__ = 'lin.chen@ieee.org'
__status__ = 'Prototype'

import csv

def write_primes(prime_list, file_name):
    """Output a list of prime numbers into a csv file

    Args:
        prime_list (list): a list of prime numbers
        file_name (str): file name of a csv file

    Raises:
        IOError: if file is not able to be opened

    Examples:
        >>> write_primes([2, 3, 5, 7], 'output.csv')

    """
    with open(file_name, 'w') as csvfile:
        writter = csv.writer(csvfile, delimiter=',')
        writter.writerow(prime_list)

def read_primes(file_name):
    """Read a list of prime numbers from a csv file

    Args:
        file_name (str): file name of a csv file

    Raises:
        IOError: if file is not able to be read

    Examples:
        >>> l = read_primes('output.csv')

    """
    with open(file_name, newline='') as csvfile:
        reader = csv.reader(csvfile, delimiter=',')
        for row in reader:
            prime_list = []
            for field in row:
                prime_list.append(int(field))
            return prime_list
		

"""Functions for prime numbers

In Spring 2020, to demo how to build a Python project, this project was
created for the students in CS4900 senior seminar class. This module contains
the functions about prime numbers.

Example:
    python primemodule.py

"""

__author__ = "Lin Chen"
__version__ = 0.1
__email__ = "lin.chen@ieee.org"
__status__ = "Prototype"

def is_prime(number):
    """Check if a number is a prime

    Args:
        number (int): integer number

    Return:
        boolean: true if n is a prime number, false otherwise

    Raises:
        ValueError: if n is not a natural number

    Examples:
        >>> b = is_prime(83)

    """
    if not isinstance(number, int):
        raise ValueError("Not an integer number")

    if number <= 0:
        raise ValueError("Not a natural number")

    if number == 1:
        return False

    for i in range(2, number):
        if number%i == 0:
            return False

    return True

def get_n_prime(num):
    """Get the fist num prime numbers

    Args:
        num (int): the number of the first prime numbers

    Return:
        list: a list of integer numbers

    Examples:
        >>> prime_list = get_n_prime(10)

    """
    current_num = 2
    count = 0
    prime_list = []

    while True:
        if is_prime(current_num):
            prime_list.append(current_num)
            count += 1
            if count == num:
                return prime_list
        current_num += 1