# -*- coding: utf-8 -*-
# soledadbootstrapper.py
# Copyright (C) 2013 LEAP
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

"""
Soledad bootstrapping
"""

import logging
import os

from PySide import QtCore

from leap.common.check import leap_assert, leap_assert_type
from leap.common.files import get_mtime
from leap.keymanager import KeyManager, openpgp
from leap.keymanager.errors import KeyNotFound
from leap.config.providerconfig import ProviderConfig
from leap.crypto.srpauth import SRPAuth
from leap.services.soledad.soledadconfig import SoledadConfig
from leap.util.request_helpers import get_content
from leap.soledad import Soledad
from leap.services.abstractbootstrapper import AbstractBootstrapper

logger = logging.getLogger(__name__)


class SoledadBootstrapper(AbstractBootstrapper):
    """
    Soledad init procedure
    """

    SOLEDAD_KEY = "soledad"
    KEYMANAGER_KEY = "keymanager"

    PUBKEY_KEY = "user[public_key]"

    # All dicts returned are of the form
    # {"passed": bool, "error": str}
    download_config = QtCore.Signal(dict)
    gen_key = QtCore.Signal(dict)

    def __init__(self):
        AbstractBootstrapper.__init__(self)

        self._provider_config = None
        self._soledad_config = None
        self._keymanager = None
        self._download_if_needed = False
        self._user = ""
        self._password = ""

    @property
    def keymanager(self):
        return self._keymanager

    @property
    def soledad(self):
        return self._soledad

    def _load_and_sync_soledad(self, srp_auth):
        """
        Once everthing is in the right place, we instantiate and sync
        Soledad

        :param srp_auth: SRPAuth object used
        :type srp_auth: SRPAuth
        """
        uuid = srp_auth.get_uid()

        prefix = os.path.join(self._soledad_config.get_path_prefix(),
                              "leap", "soledad")
        secrets_path = "%s/%s.secret" % (prefix, uuid)
        local_db_path = "%s/%s.db" % (prefix, uuid)

        # TODO: use the proper URL
        #server_url = 'https://mole.dev.bitmask.net:2424/user-%s' % (uuid,)
        server_url = 'https://gadwall.dev.bitmask.net:1111/user-%s' % (uuid,)
        # server_url = self._soledad_config.get_hosts(...)

        cert_file = self._provider_config.get_ca_cert_path()

        self._soledad = Soledad(uuid,
                                self._password.encode("utf-8"),
                                secrets_path,
                                local_db_path,
                                server_url,
                                cert_file,
                                srp_auth.get_token())
        self._soledad.sync()

    def _download_config(self):
        """
        Downloads the Soledad config for the given provider
        """

        leap_assert(self._provider_config,
                    "We need a provider configuration!")

        logger.debug("Downloading Soledad config for %s" %
                     (self._provider_config.get_domain(),))

        self._soledad_config = SoledadConfig()

        headers = {}
        mtime = get_mtime(os.path.join(self._soledad_config
                                       .get_path_prefix(),
                                       "leap",
                                       "providers",
                                       self._provider_config.get_domain(),
                                       "soledad-service.json"))

        if self._download_if_needed and mtime:
            headers['if-modified-since'] = mtime

        # there is some confusion with this uri,
        config_uri = "%s/%s/config/soledad-service.json" % (
            self._provider_config.get_api_uri(),
            self._provider_config.get_api_version())
        logger.debug('Downloading soledad config from: %s' % config_uri)

        srp_auth = SRPAuth(self._provider_config)
        session_id = srp_auth.get_session_id()
        cookies = None
        if session_id:
            cookies = {"_session_id": session_id}

        res = self._session.get(config_uri,
                                verify=self._provider_config
                                .get_ca_cert_path(),
                                headers=headers,
                                cookies=cookies)
        res.raise_for_status()

        # Not modified
        if res.status_code == 304:
            logger.debug("Soledad definition has not been modified")
        else:
            soledad_definition, mtime = get_content(res)

            self._soledad_config.load(data=soledad_definition, mtime=mtime)
            self._soledad_config.save(["leap",
                                       "providers",
                                       self._provider_config.get_domain(),
                                       "soledad-service.json"])

        self._load_and_sync_soledad(srp_auth)

    def _gen_key(self):
        """
        Generates the key pair if needed, uploads it to the webapp and
        nickserver
        """
        leap_assert(self._provider_config,
                    "We need a provider configuration!")

        address = "%s@%s" % (self._user, self._provider_config.get_domain())

        logger.debug("Retrieving key for %s" % (address,))

        srp_auth = SRPAuth(self._provider_config)
        self._keymanager = KeyManager(
            address,
            "https://%s:6425" % (self._provider_config.get_domain()),
            self._soledad,
            #token=srp_auth.get_token(), # TODO: enable token usage
            session_id=srp_auth.get_session_id(),
            ca_cert_path=self._provider_config.get_ca_cert_path(),
            api_uri=self._provider_config.get_api_uri(),
            api_version=self._provider_config.get_api_version(),
            uid=srp_auth.get_uid())
        try:
            self._keymanager.get_key(address, openpgp.OpenPGPKey,
                                     private=True, fetch_remote=False)
        except KeyNotFound:
            logger.debug("Key not found. Generating key for %s" % (address,))
            self._keymanager.gen_key(openpgp.OpenPGPKey)
            logger.debug("Key generated successfully.")

    def run_soledad_setup_checks(self,
                                 provider_config,
                                 user,
                                 password,
                                 download_if_needed=False):
        """
        Starts the checks needed for a new soledad setup

        :param provider_config: Provider configuration
        :type provider_config: ProviderConfig
        :param user: User's login
        :type user: str
        :param password: User's password
        :type password: str
        """
        leap_assert_type(provider_config, ProviderConfig)

        self._provider_config = provider_config
        self._download_if_needed = download_if_needed
        self._user = user
        self._password = password

        cb_chain = [
            (self._download_config, self.download_config),
            (self._gen_key, self.gen_key)
        ]

        self.addCallbackChain(cb_chain)
