"""Provides a common base for Nginx proxies"""
import os
import shutil
import subprocess
from typing import Set
from typing import Tuple

from certbot import configuration
from certbot_compatibility_test import errors
from certbot_compatibility_test import util
from certbot_compatibility_test.configurators import common as configurators_common
from certbot_nginx._internal import configurator
from certbot_nginx._internal import constants


class Proxy(configurators_common.Proxy):
    """A common base for Nginx test configurators"""

    def load_config(self) -> str:
        """Loads the next configuration for the plugin to test"""
        config = super().load_config()
        self._all_names, self._test_names = _get_names(config)

        server_root = _get_server_root(config)

        # XXX: Deleting all of this is kind of scary unless the test
        #      instances really each have a complete configuration!
        shutil.rmtree("/etc/nginx")
        shutil.copytree(server_root, "/etc/nginx", symlinks=True)

        self._prepare_configurator()

        try:
            subprocess.check_call("service nginx reload".split())
        except errors.Error:
            raise errors.Error(
                "Nginx failed to load {0} before tests started".format(
                    config))

        return config

    def _prepare_configurator(self) -> None:
        """Prepares the Nginx plugin for testing"""
        for k in constants.CLI_DEFAULTS:
            setattr(self.le_config, "nginx_" + k, constants.os_constant(k))

        conf = configuration.NamespaceConfig(self.le_config)
        self._configurator = configurator.NginxConfigurator(config=conf, name="nginx")
        self._configurator.prepare()

    def cleanup_from_tests(self) -> None:
        """Performs any necessary cleanup from running plugin tests"""


def _get_server_root(config: str) -> str:
    """Returns the server root directory in config"""
    subdirs = [
        name for name in os.listdir(config)
        if os.path.isdir(os.path.join(config, name))]

    if len(subdirs) != 1:
        raise errors.Error("Malformed configuration directory {0}".format(config))

    return os.path.join(config, subdirs[0].rstrip())


def _get_names(config: str) -> Tuple[Set[str], Set[str]]:
    """Returns all and testable domain names in config"""
    all_names: Set[str] = set()
    for root, _dirs, files in os.walk(config):
        for this_file in files:
            update_names = _get_server_names(root, this_file)
            all_names.update(update_names)
    non_ip_names = {n for n in all_names if not util.IP_REGEX.match(n)}
    return all_names, non_ip_names


def _get_server_names(root: str, filename: str) -> Set[str]:
    """Returns all names in a config file path"""
    all_names = set()
    with open(os.path.join(root, filename)) as f:
        for line in f:
            if line.strip().startswith("server_name"):
                names = line.partition("server_name")[2].rpartition(";")[0]
                for n in names.split():
                    # Filter out wildcards in both all_names and test_names
                    if not n.startswith("*."):
                        all_names.add(n)
    return all_names
