import glob
import json
import os
import os.path
import re
import shutil
from enum import Enum
from subprocess import call


class VpnGenError(Enum):
    Success = 0,
    VpnAlreadyExists = 1,
    VpnDoesNotExists = 2,
    ClientAlreadyExists = 3,
    ClientDoesNotExists = 4


class VpnGen:
    default_config_base_dir = ""
    default_config_file = ""
    default_client_config_file = ""
    ovpn_config_path = ""

    def __init__(self, default_config_path, ovpn_config_path):
        self.default_config_base_dir = os.path.abspath(default_config_path)
        self.default_config_file = "%s.conf" % self.default_config_base_dir
        self.default_client_config_file = "%s%sclients%sclient.conf" % (self.default_config_base_dir, os.sep, os.sep)
        self.ovpn_config_path = os.path.abspath(ovpn_config_path)

    def f7(self, seq):
        seen = set()
        seen_add = seen.add
        return [x for x in seq if not (x in seen or seen_add(x))]

    def get_vpn_vars(self):
        with open(self.default_config_file, "r") as f:
            default_config = f.read()

        variables = re.findall('\$\{([^}]+)}', default_config)
        variables += ["KEY_COUNTRY", "KEY_PROVINCE", "KEY_CITY", "KEY_ORG", "KEY_EMAIL"]
        variables = self.f7(variables)

        return variables

    def get_client_vars(self, vpn_name):
        default_client_config_path = self.get_client_default_config_path(vpn_name)
        if not os.path.exists(default_client_config_path):
            return None

        with open(default_client_config_path, "r") as f:
            default_config = f.read()
        variables = re.findall('\$\{([^}]+)}', default_config)
        variables = self.f7(variables)

        return variables

    def get_base_dir(self, vpn_name):
        return "%s%s%s%s" % (self.ovpn_config_path, os.sep, vpn_name, os.sep)

    def get_config_path(self, vpn_name):
        return "%s%s%s.conf" % (self.ovpn_config_path, os.sep, vpn_name)

    def get_vpn_variables_path(self, vpn_name):
        base_dir = self.get_base_dir(vpn_name)
        return "%svpngen.json" % base_dir

    def get_easy_rsa_dir(self, vpn_name):
        base_dir = self.get_base_dir(vpn_name)
        return "%seasy-rsa%s" % (base_dir, os.sep)

    def get_easy_rsa_key_dir(self, vpn_name):
        easyrsadir = self.get_easy_rsa_dir(vpn_name)
        return "%skeys%s" % (easyrsadir, os.sep)

    def get_pkitool_path(self, vpn_name):
        easyrsadir = self.get_easy_rsa_dir(vpn_name)
        return "%spkitool" % easyrsadir

    def get_client_default_config_path(self, vpn_name):
        base_dir = self.get_base_dir(vpn_name)
        return "%s%sclients/client.conf" % (base_dir, os.sep)

    def get_client_dir(self, vpn_name, client_name):
        base_dir = self.get_base_dir(vpn_name)
        return "%sclients%s%s-%s%s" % (base_dir, os.sep, client_name, vpn_name, os.sep)

    def get_client_config_path(self, vpn_name, client_name):
        client_dir = self.get_client_dir(vpn_name, client_name)
        return "%s%s-%s.conf" % (client_dir, client_name, vpn_name)

    def get_client_generated_files_paths(self, vpn_name, client_name):
        keys_dir = self.get_easy_rsa_key_dir(vpn_name,)
        return [
            "%s%s.crt" % (keys_dir, client_name),
            "%s%s.key" % (keys_dir, client_name)
        ]

    def get_client_tarball_path(self, vpn_name, client_name):
        base_dir = self.get_base_dir(vpn_name)
        return "%sclients%s%s-%s.tar.bz2" % (base_dir, os.sep, client_name, vpn_name)

    def get_server_needed_files_paths(self, vpn_name):
        keys_dir = self.get_easy_rsa_key_dir(vpn_name)
        return [
            "%sca.crt" % keys_dir,
            "%sta.key" % keys_dir
        ]

    def get_all_needed_files_paths(self, vpn_name, client_name):
        return self.get_client_generated_files_paths(vpn_name, client_name) +\
               self.get_server_needed_files_paths(vpn_name)

    def setup_vars(self, vpn_name, variables):
        easyrsadir = self.get_easy_rsa_dir(vpn_name)

        os.environ["KEY_COUNTRY"] = variables['KEY_COUNTRY']
        os.environ["KEY_PROVINCE"] = variables['KEY_PROVINCE']
        os.environ["KEY_CITY"] = variables['KEY_CITY']
        os.environ["KEY_ORG"] = variables['KEY_ORG']
        os.environ["KEY_OU"] = variables['KEY_ORG']
        os.environ["KEY_CN"] = variables['KEY_ORG']
        os.environ["KEY_NAME"] = variables['KEY_ORG']
        os.environ["KEY_EMAIL"] = variables['KEY_EMAIL']
        os.environ["KEY_SIZE"] = variables['KEY_SIZE']
        os.environ["CA_EXPIRE"] = variables['CA_EXPIRE']
        os.environ["KEY_EXPIRE"] = variables['KEY_EXPIRE']

        os.environ["EASY_RSA"] = easyrsadir
        os.environ["OPENSSL"] = "openssl"
        os.environ["PKCS11TOOL"] = "pkcs11-tool"
        os.environ["GREP"] = "grep"
        os.environ["KEY_CONFIG"] = "%s%s" % (easyrsadir, "openssl.cnf")
        os.environ["KEY_DIR"] = "%s%s" % (easyrsadir, "keys")
        os.environ["PKCS11_MODULE_PATH"] = "dummy"
        os.environ["PKCS11_PIN"] = "dummy"

    def create_vpn(self, vpn_name, variables):
        base_dir = self.get_base_dir(vpn_name)
        conf_file = self.get_config_path(vpn_name)
        conf_vpngen_file = self.get_vpn_variables_path(vpn_name)
        if os.path.exists(base_dir) or os.path.exists(conf_file):
            return VpnGenError.VpnAlreadyExists

        with open(self.default_config_file, "r") as f:
            default_config = f.read()

        variables['name'] = vpn_name
        for variable in variables:
            default_config = default_config.replace("${%s}" % variable, variables[variable])

        os.makedirs(base_dir)
        with open(conf_file, "w") as f:
            f.write(default_config)

        os.rmdir(base_dir)
        shutil.copytree(self.default_config_base_dir, base_dir)

        curdir = os.curdir
        easyrsadir = self.get_easy_rsa_dir(vpn_name)
        pkitool = self.get_pkitool_path(vpn_name)
        os.chdir(easyrsadir)

        self.setup_vars(vpn_name, variables)

        call([".%sclean-all" % os.sep])
        call([pkitool, "--initca", "-batch"])
        call([pkitool, "--server", "server", "-batch"])
        call([".%sbuild-dh" % os.sep])
        call(["openssl", "ca", "-gencrl",
              "-keyfile", "keys%sca.key" % os.sep,
              "-cert", "keys%sca.crt" % os.sep,
              "-out", "keys%scrl.pem" % os.sep,
              "-config", "openssl.cnf"])

        del os.environ["KEY_OU"]
        del os.environ["KEY_CN"]
        del os.environ["KEY_NAME"]

        call(["openvpn", "--genkey", "--secret", "keys%sta.key" % os.sep])

        with open(conf_vpngen_file, "w") as f:
            json.dump({'variables': variables}, f, indent=4, separators=(',', ': '))

        os.chdir(curdir)

        return VpnGenError.Success

    def remove_vpn(self, vpn_name):
        base_dir = self.get_base_dir(vpn_name)
        conf_file = self.get_config_path(vpn_name)
        if not os.path.exists(base_dir) and not os.path.exists(conf_file):
            return VpnGenError.VpnDoesNotExists
        os.remove(conf_file)
        shutil.rmtree(base_dir)
        return VpnGenError.Success

    def create_client(self, vpn_name, client_name, variables):
        base_dir = self.get_base_dir(vpn_name)
        if not os.path.exists(base_dir):
            return VpnGenError.VpnDoesNotExists
        client_dir = self.get_client_dir(vpn_name, client_name)
        if os.path.exists(client_dir):
            return VpnGenError.ClientAlreadyExists

        curdir = os.curdir
        easyrsadir = self.get_easy_rsa_dir(vpn_name)
        pkitool = self.get_pkitool_path(vpn_name)
        os.chdir(easyrsadir)

        self.setup_vars(vpn_name, variables)
        os.environ["KEY_CN"] = client_name
        os.environ["KEY_NAME"] = client_name

        call([pkitool, client_name])

        os.chdir(curdir)

        self.build_client(vpn_name, client_name, variables)

        return VpnGenError.Success

    def remove_client(self, vpn_name, client_name):
        base_dir = self.get_base_dir(vpn_name)
        if not os.path.exists(base_dir):
            return VpnGenError.VpnDoesNotExists
        client_dir = self.get_client_dir(vpn_name, client_name)
        if not os.path.exists(client_dir):
            return VpnGenError.ClientDoesNotExists
        return VpnGenError.Success

    def rebuild_clients(self, vpn_name):
        base_dir = self.get_base_dir(vpn_name)
        return VpnGenError.Success

    def build_client(self, vpn_name, client_name, variables):
        client_dir = self.get_client_dir(vpn_name, client_name)
        client_conf_file = self.get_client_config_path(vpn_name, client_name)
        client_default_config_path = self.get_client_default_config_path(vpn_name)

        with open(client_default_config_path, "r") as f:
            client_default_config = f.read()

        variables['name'] = vpn_name
        variables['client'] = client_name
        for variable in variables:
            client_default_config = client_default_config.replace("${%s}" % variable, variables[variable])

        os.makedirs(client_dir)
        with open(client_conf_file, "w") as f:
            f.write(client_default_config)

        files_paths = self.get_all_needed_files_paths(vpn_name, client_name)
        for file_path in files_paths:
            split = os.path.splitext(file_path)
            dest = "%s%s-%s%s" % (client_dir, os.path.basename(split[0]), vpn_name, split[1])
            shutil.copy(file_path, dest)

        files_names = glob.glob("%s%s*" % (client_dir, os.sep))
        files_names = list(map(lambda file_path: os.path.basename(file_path), files_names))

        call(["tar", "cfj", self.get_client_tarball_path(vpn_name, client_name),
              "-C", client_dir] + files_names)