"""
This script uses argparse to parse command line arguments.

It imports the required modules and sets up a parser with basic options for demonstration purposes.
"""

import argparse
import yoshi.crypto as crypto
import yoshi.database as database
import yoshi.process as process

def yoshi():
    parser = argparse.ArgumentParser(
        description='Manage your username and passwords via a convenient CLI vault.'
    )

    # Top-level arguments
    group_one = parser.add_mutually_exclusive_group()
    group_one.add_argument(
        '-n', '--new',
        help='Create a new account.',
        action='store_true'
    )
    group_one.add_argument(
        '-l', '--list',
        help='List all saved accounts.',
        action='store_true'
    )
    group_one.add_argument(
        '-e', '--edit',
        help='Edit a saved account.',
        action='store_true'
    )
    group_one.add_argument(
        '-d', '--delete',
        help='Delete a saved account.',
        action='store_true'
    )
    group_one.add_argument(
        '--purge',
        help=(
            'Purge all accounts and delete the vault. '
            '(Caution: this will irreversibly destroy your data.)'
        ),
        action='store_true'
    )
    group_one.add_argument(
        '--encrypt',
        help='Encrypt the vault.',
        action='store_true'
    )
    group_one.add_argument(
        '--decrypt',
        help='Decrypt the vault.',
        action='store_true'
    )

    # Encryption flags
    group_two = parser.add_mutually_exclusive_group()
    group_two.add_argument(
        '-g', '--generate',
        help=(
            'When using the --encrypt option, generate a new encryption key.'
        ),
        action='store_true'
    )
    group_two.add_argument(
        '-k', '--keyfile',
        help='Path to existing key file.',
        action='store',
        nargs=1,
        type=str
    )

    # Edit flags
    group_three = parser.add_argument_group()
    group_three.add_argument(
        '-u', '--uuid',
        help=(
            'When using the --edit or --delete options, provide the account UUID.'
        ),
        action='store',
        nargs=1,
        type=str
    )
    group_three.add_argument(
        '-f', '--field',
        help=(
            'When using the --edit option, specify the field to edit (integer index).'
        ),
        action='store',
        nargs=1,
        type=int
    )

    args = parser.parse_args()

    if args.decrypt:
        if args.keyfile:
            key = crypto.load_key(args.keyfile[0])
        else:
            key = input('Please enter your decryption key: ')
        crypto.decrypt(key)
    elif args.encrypt:
        if args.generate:
            key = crypto.generate_key()
            print(
                'WRITE THIS KEY DOWN SOMEWHERE SAFE. YOU WILL NOT BE ABLE TO DECRYPT '
                'YOUR DATA WITHOUT IT!'
            )
            print(key.decode())
            print('\n')
        else:
            if args.keyfile:
                key = crypto.load_key(args.keyfile[0])
            else:
                key = input('Please enter your encryption key: ')
        crypto.encrypt(key)
    elif database.check_table():
        if args.new:
            process.create_account()
        elif args.list:
            process.list_accounts()
        elif args.edit:
            process.edit_account(args.uuid[0], args.field[0])
        elif args.delete:
            process.delete_account(args.uuid[0])
        elif args.purge:
            process.purge_accounts()
        else:
            raise TypeError(
                'Please specify a command or use the --help flag for more information.'
            )

if __name__ == "__main__":
    yoshi()