import csv
import random
import os

#--CONSTANTS & FUNCS
USERS = 'users.csv'
SONGS = 'songs.csv'

def get_song_string(song):
    '''Returns a sting based on the song argument: only each letter is shown'''
    output = ''
    words = song.split(' ')
    for word in words:
        output += word[0] + ('_'*(len(word)-1)) + ' '
    return output

#--AUTHENTICATION--
while True:
    try:
        account = {'y':True, 'yes':True, 'n':False,'no':False}[input('Do you have an account already? (y/n) ').lower()]
        break
    except:
        pass

username = input('Username: ')
password = input('Password: ')

if account:
    #check & continue
    found = False
    with open(USERS) as f:
        for row in csv.reader(f):
            if row[0] == username:
                #user exists
                found = True
                if row[1] != password:
                    print("You have entered an incorrect password. Please try again.")
                    raise SystemExit

    if not found:
        print("The account '{}' doesn't exist".format(username))
        raise SystemExit

else:
    #add & continue
    existing = False
    with open(USERS) as f:
        for row in csv.reader(f):
            if row[0] == username:
                existing = True

    if not existing:
        with open(USERS, 'a', newline='\n') as f:
            csv.writer(f).writerow([username, password])
            print('Account made successfully!')
    else:
        print('This username is already taken, please try again with another username.')
        raise SystemExit

#--GAME--
with open(SONGS) as f:
    songs = [row for row in csv.reader(f)]

game = True
points = 0
while game: #game repeats
    print() #seperates authentication and each question
    choice = random.choice(songs) #changes song
    attempts = 2 #attempts left at each question
    guess_number = 0 #keeps track of which guess the user is on

    while True: #while still playing
        if attempts == 0:
            game = False
            break

        print('Artist: {}\nSong: {}'.format(choice[0], get_song_string(choice[1])))

        guess = input('What do you think the song is called? ')
        if guess != '':
            if guess.lower() == choice[1].lower():
                print('Correct!')
                if guess_number == 0: #if correct on the first go
                    points += 3
                else:
                    points += 1
                break
            else:
                print('Incorrect!')
                attempts -= 1
                guess_number += 1

print('\nYou got {} point{}.'.format('no' if points == 0 else points, '' if points == 1 else 's'))

leaderboard = []

#write to a new file
with open(USERS) as f:
    reader = csv.reader(f)
    with open('new_users.csv','w', newline='\n') as new_f:
        writer = csv.writer(new_f)
        for row in reader:
            if row[0] == username and points > int(row[2]):
                new_row = [row[0],row[1],str(points)]
                leaderboard.append(new_row)
                writer.writerow(new_row)
            else:
                leaderboard.append(row)
                writer.writerow(row)

#replace it with old file
os.remove('users.csv')
os.rename('new_users.csv', 'users.csv')

##--LEADERBOARD--
print('\n--LEADERBOARD--')
leaderboard.sort(key=lambda x: -int(x[2]))
for user in leaderboard[:5]:
    print('{}: {}'.format(user[0], user[2]))