# -*- coding: utf-8 -*-
"""
generate_keyring command

Assemble a GPG keyring with all known developer keys.

Usage: ./manage.py generate_keyring <keyserver> <keyring_path>
"""

from django.core.management.base import BaseCommand, CommandError

import logging
import subprocess
import sys

from devel.models import MasterKey, UserProfile

logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s -> %(levelname)s: %(message)s',
    datefmt='%Y-%m-%d %H:%M:%S',
    stream=sys.stderr)
logger = logging.getLogger()

class Command(BaseCommand):
    args = "<keyserver> <keyring_path> [ownertrust_path]"
    help = "Assemble a GPG keyring with all known developer keys."

    def handle(self, *args, **options):
        v = int(options.get('verbosity', None))
        if v == 0:
            logger.level = logging.ERROR
        elif v == 1:
            logger.level = logging.INFO
        elif v >= 2:
            logger.level = logging.DEBUG

        if len(args) < 2:
            raise CommandError("keyserver and keyring_path must be provided")

        generate_keyring(args[0], args[1])

        if len(args) > 2:
            generate_ownertrust(args[2])


def generate_keyring(keyserver, keyring):
    logger.info("getting all known key IDs")

    # Screw you Django, for not letting one natively do value != <empty string>
    key_ids = UserProfile.objects.filter(
            pgp_key__isnull=False).extra(where=["pgp_key != ''"]).values_list(
            "pgp_key", flat=True)
    logger.info("%d keys fetched from user profiles", len(key_ids))
    master_key_ids = MasterKey.objects.values_list("pgp_key", flat=True)
    logger.info("%d keys fetched from master keys", len(master_key_ids))

    # GPG is stupid and interprets any filename without path portion as being
    # in ~/.gnupg/. Fake it out if we just get a bare filename.
    if '/' not in keyring:
        keyring = './%s' % keyring
    gpg_cmd = ["gpg", "--no-default-keyring", "--keyring", keyring,
            "--keyserver", keyserver, "--recv-keys"]
    logger.info("running command: %r", gpg_cmd)
    gpg_cmd.extend(key_ids)
    gpg_cmd.extend(master_key_ids)
    subprocess.check_call(gpg_cmd)
    logger.info("keyring at %s successfully updated", keyring)


TRUST_LEVELS = {
    'unknown': 0,
    'expired': 1,
    'undefined': 2,
    'never': 3,
    'marginal': 4,
    'fully': 5,
    'ultimate': 6,
}


def generate_ownertrust(trust_path):
    master_key_ids = MasterKey.objects.values_list("pgp_key", flat=True)
    with open(trust_path, "w") as trustfile:
        for key_id in master_key_ids:
            trustfile.write("%s:%d:\n" % (key_id, TRUST_LEVELS['marginal']))
    logger.info("trust file at %s created or overwritten", trust_path)

# vim: set ts=4 sw=4 et:
