import csv
import random
import string
import os
import sqlite3

from Crypto.Cipher import AES

# path "C:\Users\eps.scl\Desktop\temp.txt"

# ANSI color
black = "\033[0;30m"
red = "\033[0;31m"
green = "\033[0;32m"
yellow = "\033[0;33m"
white = "\033[0;37m"
cyan = "\033[0;36m"
nocolor = "\033[0m"


conn = sqlite3.connect('pwd.db')
cursor=conn.cursor()
cursor.execute('''
    create table if not exists manager(
    pwd VARCHAR(15) PRIMARY KEY
    )
''')
result = cursor.execute('select * from manager')


file=result.fetchall()

if file == []:
    password=input('Enter your new password')
    print('password created')
    ins=f'insert into manager(pwd) values(?)'
    cursor.execute(ins, (password,))
    conn.commit()
else:
    password = input('Enter your password')
    print(file)
    if password == file[0][0]:
        print('Successfully logged in')
    else:
        print('wrong password entered')
key=password

conn.close()
    


def genPasswd(password: str):
    """
    Password must be 16, 24 or 32 bytes long.
    Function checks length of password and returns string of matching length.
    """
    length = len(password)
    if length not in (16, 24, 32):
        if length > 24:
            password += " " * (32 - length)
        elif length > 16:
            password += " " * (24 - length)
        elif length < 16:
            password += " " * (16 - length)

    return password.encode()


def encrypt(title: str, key: str, password: str):
    """
    title: Identifying name of the data stored
    key: the master password
    password: the password to be stored
    """

    cipher = genPasswd(key)
    line = AES.new(cipher, AES.MODE_EAX)
    ciphertext, tag = line.encrypt_and_digest(password.encode())

    with open(r"temp.txt", "a", newline="") as store:
        writer = csv.writer(store, delimiter=",")
        writer.writerow([title, ciphertext, tag, line.nonce])


def decrypt(key):
    """
    Decrypts all data.
    """
    cipher = genPasswd(key)
    with open(r"temp.txt", "r", newline="") as store:
        reader = list(csv.reader(store, delimiter=","))
        data = []
        try:
            for line in reader:
                lock = AES.new(cipher, AES.MODE_EAX, eval(line[3]))
                data.append((line[0], lock.decrypt_and_verify(eval(line[1]), eval(line[2])).decode()))
        except ValueError:
            print(red+"Invalid password"+nocolor)
        if data:
            print(yellow+"{:<10} {:<10}\n".format("Title", "Password")+nocolor)
            for line in data:
                print(yellow+"{:<10} {:<10}".format(line[0], line[1])+nocolor)


def hashtitle(title):
    
    cipher = genPasswd(key)
    with open(r"temp.txt", "r", newline="") as store:
        reader = list(csv.reader(store, delimiter=","))
        try:
            data = {}
            for line in reader:
                lock = AES.new(cipher, AES.MODE_EAX, eval(line[3]))
                data[line[0]] = line[1], line[2], line[3]
            try:
                datareq = data[title]
            except KeyError:
                print(red+"Unable to find entry"+nocolor)
                return
            else:
                return datareq
        except ValueError:
            print(red+"Invalid password"+nocolor)

    


def moditem(title):
    record = createBufferList(title)
    if record == None:
        return
    field = input("Enter field to be changed"+cyan+"(title, password)"+nocolor+": ")
    fieldIndex = {"title": 1, "username": 2, "password": 3}.get(field.lower())
    if fieldIndex == None:
        print(red+"Unknown Field"+nocolor)
        return
    newField = input(f"Enter new {field}: ")
    if not newField:
        print(red+"Invalid Data."+nocolor)
        return
    
    if fieldIndex == 1:
        hashbin = hashtitle(title)
        deleteitem(title)
        with open(r"temp.txt", "a", newline="") as store:
            writer = csv.writer(store, delimiter=",")
            writer.writerow([newField, *hashbin])
        print(green+"Successfully modified data."+nocolor)
            
    elif fieldIndex == 2:
        pass
    
    elif fieldIndex == 3:
        deleteitem(title)
        encrypt(title, key, newField)
        print(green+"Successfully modified data."+nocolor)

def listOftitles():
    with open(r"temp.txt", "r", newline="") as store:
        reader = list(csv.reader(store, delimiter=","))
        data = []
        for line in reader:
            data.append(line[0].lower().strip())
        return data


def createBufferList(title):
    with open(r"temp.txt", "r", newline="") as store:
        reader = list(csv.reader(store, delimiter=","))
        record = []
        for line in reader:
            if line[0] == title:
                continue
            record.append(line)
        if record == reader:
            print(red+"Item not found"+nocolor)
            return
        return record


def deleteitem(title):
    record = createBufferList(title)
    if record == None:
        return
    with open(r"temp.txt", "w", newline="") as store:
        writer = csv.writer(store, delimiter=",")
        writer.writerows(record)


def generatePassword():
    """
    Generates a random password and asks to save the password.
    """
    count = input("Enter length of password (Default - 12): ")
    try:
        count = int(count)
    except ValueError:
        print("Using default value - 12\n")
        count = 12
    password = "".join(
        random.choice(string.ascii_letters + string.digits) for _ in range(int(count))
    )
    print("-" * os.get_terminal_size()[0])
    print(yellow+f"{password}"+nocolor)
    print("-" * os.get_terminal_size()[0])
    save = input("Save Password? y/n: ")
    if save == "y":
        title = input("Enter a title: ")
        if title in listOftitles():
            print(red+"This item already exists"+nocolor)
            return
        elif not title:
            print(red+"Invalid input: cannnot accept empty name."+nocolor)
            return
        encrypt(title, key, password)
        print(green+"Successfully created data."+nocolor)
    elif save == "n":
        pass
    else:
        pass


def main():
    while True:
        print("\n"+"-" * os.get_terminal_size()[0])
##        sys.stdout.write("\033[FF") # Cursor up one line
        print(cyan+"1:"+nocolor+" View all Passwords")
        print(cyan+"2:"+nocolor+" Create a new Password Entry")
        print(cyan+"3:"+nocolor+" Modify Existing Password Entry")
        print(cyan+"4:"+nocolor+" Delete a Password Entry")
        print(cyan+"5:"+nocolor+" Generate a New Random Password")
        print(cyan+"q:"+nocolor+" Quit")
        choice = input("Enter your choice"+cyan+"(1, 2, 3, 4, 5, q)"+nocolor+": ")
        print("-" * os.get_terminal_size()[0])
        os.system('cls')
        if choice == "1":
            decrypt(key)
        elif choice == "2":
            title = input("Enter a title: ")
            if title in listOftitles():
                print(red+"Invalid name; this name is already in use."+nocolor)
                continue
            elif not title:
                print(red+"Cannot accept an empty value."+nocolor)
                continue
            pw = input("Enter a Password: ")
            if not pw:
                print(red+"Cannot accept an empty value."+nocolor)
                continue
            encrypt(title, key, pw)
            print(green+"Successfully created password."+nocolor)
        elif choice == "3":
            while True:
                title = input(
                    "Enter the title of the password to be modified(press Enter to list): "
                )
                if title == "":
                    decrypt(key)
                else:
                    break
            moditem(title)
        elif choice == "4":
            while True:
                title = input(
                    "Enter the title of the password to be deleted(press Enter to list): "
                )
                if title == "":
                    decrypt(key)
                else:
                    break
            deleteitem(title)
        elif choice == "5":
            generatePassword()
        elif choice == "q":
            break


if __name__ == "__main__":
    try:
        main()
    except KeyboardInterrupt:
        pass