import sqlite3
from datetime import datetime, timedelta

class otp:
    
    def connection():
        try:
            conn = sqlite3.connect('otp.db')
            cursor = conn.cursor()
            cursor.execute('''CREATE TABLE IF NOT EXISTS sessions (email text UNIQUE, code integer, datedel text)''')
            conn.commit()
            conn.close()
            return True
        except:
            return False


    def check_code(email):
        if (otp.connection()):
            exists = '''SELECT email FROM sessions WHERE email = ? LIMIT 1'''
            conn = sqlite3.connect('otp.db')
            cursor = conn.cursor()
            cursor.execute(exists, (email, ))
            result = cursor.fetchone()
            if (result == None):
                conn.close()
            else:
                past_sql = '''SELECT datedel FROM sessions WHERE email = ? LIMIT 1'''
                cursor.execute(past_sql, (email, ))
                fetch_past = cursor.fetchone()
                past = fetch_past[0]
                present = datetime.now()
                if (str(present) > past):
                    del_sql = '''DELETE FROM sessions WHERE email = ?'''
                    cursor.execute(del_sql, (email, ))
                    conn.commit()
                    conn.close()
                    return False
            return True
    
    def authenticate(email, user_otp):
        if (otp.check_code(email)):
            conn = sqlite3.connect('otp.db')
            cursor = conn.cursor()
            match_sql = '''SELECT code FROM sessions WHERE email = ? LIMIT 1'''
            cursor.execute(match_sql, (email, ))
            fetch_otp = cursor.fetchone()
            print(fetch_otp[0])
            print(user_otp)
            if (str(fetch_otp[0]) == str(user_otp)):
                conn.close()
                return True
            else:
                conn.close()
                return False