project1

# regular expressions library for email and password validation
import re

# our required pattern for email address
regex = r'[a-z A-Z][\w\._a-z A-Z]+[@]\w+[\.][\w]{2,3}'

# register function to register our credentials after they satisfy our requirements
def register():
    db = open('credentialsdb.txt','w+')
    db = open('credentialsdb.txt','r')
    Email = input('Enter your email address :')
    if (re.fullmatch(regex,Email)):
        print('Email address is valid !')
        Password = input('Enter your password :')
        Password1 = input('Enter your password to confirm :')
        
        emaillist = []
        pwlist = []
        
        for i in db:
            a,b=i.split(',')
            b=b.strip()
            emaillist.append(a)
            pwlist.append(b)
            global data
        data = dict(zip(emaillist,pwlist))
        #print(data)
    else:
        print('\nEmail address should meet the following requirements. Please try again !')
        print('''
                 * Should not start with special character or a number\n
                 * Should have "@" and "." in the following order\n
                 * "@" should not be immediately followed by a "."
                 ''')
        register()

    if Password != Password1:
        print('Passwords do not match. Please try again !')
        register()
    else:
        if ((re.search("[a-z]", Password)) and re.search("[A-Z]", Password) and re.search("[0-9]", Password) and (len(Password)>=5 and len(Password)<=16) and re.search("[`~!@#$%^&*:<,>.?/'\']", Password)):
            db = open('credentialsdb.txt', 'a')
            db.write(Email+','+Password+'\n')
            print('\nRegistration successful. Please proceed to login !')
        else:
            print('\nPassword should meet the following requirements. Please try again !')
            print('''
                # Password should be 5 to 16 characters long\n
                # Must have a minimum of\n
                    # one uppercase\n
                    # one lowercase\n
                    # one digit\n
                    # one special character\n
                ''')
            register()

# access function to log into the portal
# accepts email address as input
# if email exists in the dictionary 'data', then password is asked as input
# if password matches with the stored value, success message is displayed

def access():
    global data
    #print(data)
    db = open('credentialsdb.txt','r')
    Email = input('\nEnter your email address :')
    
    emaillist = []
    pwlist = []
    for i in db:
        a,b=i.split(',')
        b=b.strip()
        emaillist.append(a)
        pwlist.append(b)
    data = dict(zip(emaillist,pwlist))
        
    if Email in data:
        Password = input('Enter your password:')
        if Password == data[Email]:
            print('Login Success !')
            print('Hi,',Email)
        else:
            print('Incorrect password. Please check !')
            access()
    else:
        print("Your email address does not exist !")
        register()
        
# forgotpass function helps the user to recover the password
# user can simply type in his email address and press enter
def forgotpass():
    print()
    Email = input('Enter your email address :')
    if Email in data:
        print('Your password : ', data.get(Email))
    else:
        register()

# home function accepts only three inputs i.e. 'Login', 'Register', 'Forgot Password'
# depending on the input the corresponding function is initialized
# if the user does not enter any of the given options, home function is initialized again
# the user cannot proceed further if the user enters any random value

def home():
    option = input('Register | Login | Forgot Password ')
    if option == 'Login':
        access()
    elif option == 'Register':
        register()
    elif option == 'Forgot Password':
        forgotpass()
    else:
        print('Please enter an option !')
        home()
home()