app.py

from flask import Flask, render_template, request, send_file
from random import randint

app = Flask(__name__)


def luhn_checksum(card_number):
    def digits_of(n):
        return [int(d) for d in str(n)]
    digits = digits_of(card_number)
    odd_digits = digits[-1::-2]
    even_digits = digits[-2::-2]
    checksum = 0
    checksum += sum(odd_digits)
    for d in even_digits:
        checksum += sum(digits_of(d*2))
    return checksum % 10


def is_luhn_valid(card_number):
    return luhn_checksum(card_number) == 0


def add_prefix(prefix, num):
    return int(prefix + str(num))


def add_suffix(suffix, num):
    return int(str(num) + str(suffix))


def gen_bin(n, p_card):
    n = int(n)
    print(n)

    if (n <= 10000):
        i = 0
        while i != n:
            range_start = 10**(5-1)
            range_end = (10**5)-1
            f = open("/tmp/cards.txt", "a")

            pre_num = randint(range_start, range_end)
            num = add_prefix(p_card, pre_num)
            if p_card == 34 or 37:
                range_start = 10**(8-1)
                range_end = (10**8)-1
            else:
                range_start = 10**(10-1)
                range_end = (10**10)-1

            suff_num = randint(range_start, range_end)
            num = add_suffix(suff_num, num)

            res = is_luhn_valid(num)
            if res:
                f.write(f"{num}\n")
                i += 1
        print("Done!")
    else:
        return 1


@app.route('/', methods=['GET', 'POST'])
def home():
    if request.method == 'POST':
        open('/tmp/cards.txt', 'w').close()
        num = request.form.get('num')
        card_t = request.form.get('card_type')

        print("Generating...")

        if num and card_t:
            check = gen_bin(num, card_t)
            print(check)
            if (check):
                return render_template("Error.html")
            else:
                path = '/tmp/cards.txt'
                return send_file(path, as_attachment=True)
        else:
            return render_template("EnterInput.html")

    else:
        return render_template("index.html")