#!/usr/bin/env python3
# link: https://git.p2p.legal/aya/dpgpid/
# desc: dpgpid builds a decentralized gpg world of trust with did over ipfs

# Copyleft 2022 Yann Autissier <aya@asycn.io>

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.

import argparse
import configparser
import logging as log
import os
import sys

from about import __version__
import key

class keygen:
    def __init__(self):
        self.parser = argparse.ArgumentParser(description="""
        Generate ed25519 keys for duniter and ipfs from gpg.
        It converts a gpg key, a duniter username/password, or any ed25519 key to
        a duniter wallet or an IPFS key.""")
        self.parser.add_argument(
            "-d",
            "--debug",
            action="store_true",
            help="show debug informations (WARNING: including SECRET KEY)",
        )
        self.parser.add_argument(
            "-f",
            "--format",
            choices=['ewif', 'jwk', 'nacl','p2p','pem','pubsec','seed','wif'],
            default=None,
            dest="format",
            help="output file format, default: pem (pkcs8)",
        )
        self.parser.add_argument(
            "-g",
            "--gpg",
            action="store_true",
            help="use gpg key with uid matched by username",
        )
        self.parser.add_argument(
            "-i",
            "--input",
            dest="input",
            help="read ed25519 key from file FILE, autodetect format: {credentials,ewif,jwk,nacl,mnemonic,p2p,pem,pubsec,seed,wif}",
            metavar='FILE',
        )
        self.parser.add_argument(
            "-k",
            "--keys",
            action="store_true",
            help="show public and secret keys",
        )
        self.parser.add_argument(
            "-m",
            "--mnemonic",
            action="store_true",
            help="use username as a DUBP mnemonic passphrase",
        )
        self.parser.add_argument(
            "-o",
            "--output",
            dest="output",
            default=None,
            help="write ed25519 key to file FILE",
            metavar='FILE',
        )
        self.parser.add_argument(
            "-p",
            "--password",
            dest="password",
            help="user password for duniter, gpg key and file encryption",
        )
        self.parser.add_argument(
            "-q",
            "--quiet",
            action="store_true",
            help="show only errors",
        )
        self.parser.add_argument(
            "-s",
            "--secret",
            action="store_true",
            help="show only secret key",
        )
        self.parser.add_argument(
            "-t",
            "--type",
            choices=['b36mf', 'b58mf', 'b58mh','b64mh','base58','base64','duniter','ipfs','jwk'],
            default="base58",
            dest="type",
            help="output text format, default: base58",
        )
        self.parser.add_argument(
            "-v",
            "--verbose",
            action="store_true",
            help="show more informations",
        )
        self.parser.add_argument(
            "--version",
            action="store_true",
            help="show version and exit",
        )
        self.parser.add_argument(
            'username',
            help="username, mnemonic or gpg key",
            nargs="*",
        )

    def _check_args(self, args):
        log.debug("keygen()._check_args(%s)" % args)
        if self.input is None and not len(self.username):
            self.parser.error('keygen requires an input file or a username')

    def _cli(self, argv):
        args = self.parser.parse_args(argv)
        vars(self).update(vars(args))

        # display version
        if args.version:
            version()
            sys.exit()

        # define log format
        log_format='%(asctime)s %(levelname)s: %(message)s'
        log_datefmt='%Y/%m/%d %H:%M:%S'
        if args.debug:
            log_level='DEBUG'
        elif args.quiet:
            log_level='ERROR'
        elif args.verbose:
            log_level='INFO'
        else:
            log_level='WARNING'
        log.basicConfig(format=log_format, datefmt=log_datefmt, level=log_level)
        log.debug("keygen()._cli(%s)" % argv)

        self._check_args(args)
        self._load_config()
        self.key = key.from_args(args, self.config)
        method = getattr(self, f'do_{self.type}', self._invalid_type)
        return method()

    def _invalid_type(self):
        log.debug("keygen()._invalid_type()")
        self.parser.error(f"type {self.type} is not valid.")

    def _load_config(self):
        log.debug("keygen()._load_config()")
        self.config = configparser.RawConfigParser()
        config_dir = os.path.join(os.environ.get('XDG_CONFIG_HOME', os.path.expanduser('~/.config')), 'dpgpid')
        log.debug("config_dir=%s" % config_dir)
        self.config.read( [config_dir + '/keygen.conf'] )

    def _output(self):
        log.debug("keygen()._output()")
        if self.output is None:
            self._output_text()
        else:
            self._output_file()
            os.chmod(self.output, 0o600)

    def _output_file(self):
        log.debug("keygen()._output_file()")
        self.key.to_file(self.output, self.format, self.password)

    def _output_text(self):
        log.debug("keygen()._output_text()")
        if self.keys or not self.secret:
            print("%s" % self.public_key)
        if self.keys or self.secret:
            print("%s" % self.secret_key)

    def do_b36mf(self):
        log.debug("keygen().do_b36mf()")
        self.key.to_b36mf()
        self.public_key = self.key.public_b36mf
        self.secret_key = self.key.secret_b36mf
        self._output()

    def do_b58mf(self):
        log.debug("keygen().do_b58mf()")
        self.key.to_b58mf()
        self.public_key = self.key.public_b58mf
        self.secret_key = self.key.secret_b58mf
        self._output()

    def do_b58mh(self):
        log.debug("keygen().do_b58mh()")
        self.key.to_b58mh()
        self.public_key = self.key.public_b58mh
        self.secret_key = self.key.secret_b58mh
        self._output()

    def do_b64mh(self):
        log.debug("keygen().do_b64mh()")
        self.key.to_b64mh()
        self.public_key = self.key.public_b64mh
        self.secret_key = self.key.secret_b64mh
        self._output()

    def do_base58(self):
        log.debug("keygen().do_base58()")
        self.key.to_base58()
        self.public_key = self.key.public_base58
        self.secret_key = self.key.secret_base58
        self._output()

    def do_base64(self):
        log.debug("keygen().do_base64()")
        self.key.to_base64()
        self.public_key = self.key.public_base64
        self.secret_key = self.key.secret_base64
        self._output()

    def do_duniter(self):
        log.debug("keygen().do_duniter()")
        if not self.format:
            self.format = 'pubsec'
        self.key.to_base58()
        self.public_key = self.key.public_base58
        self.secret_key = self.key.secret_base58
        self._output()

    def do_ipfs(self):
        log.debug("keygen().do_ipfs()")
        self.key.to_b58mh()
        self.key.to_b64mh()
        self.public_key = self.key.public_b58mh
        self.secret_key = self.key.secret_b64mh
        self._output()

    def do_jwk(self):
        log.debug("keygen().do_jwk()")
        self.key.to_jwk()
        self.public_key = self.key.public_jwk
        self.secret_key = self.key.secret_jwk
        self._output()

def main(argv=None):
    if argv is None:
        argv = sys.argv[1:]
    return keygen()._cli(argv)

def version(version=__version__):
    print("%s v%s" % (sys.argv[0],version))

if __name__ == "__main__":
    sys.exit(main())