from io import StringIO
from textwrap import dedent

import pytest
import yaml

from ..config import yaml_dump
from ..profile import Profile


class TestYamlDump:

    def test_dump_to_string(self):
        """The method returns YAML data as a string by default."""
        data = {'foo': 'bar', 'baz': [1, 2]}
        result = yaml_dump(data)
        assert yaml.safe_load(stream=StringIO(result)) == data

    def test_dump_to_file(self):
        """The method dumps YAML data to the specified file."""
        data = {'foo': 'bar', 'baz': [1, 2]}
        fh = StringIO()
        result = yaml_dump(data, fh=fh)
        fh.seek(0)
        assert result is None
        assert yaml.safe_load(stream=fh) == data


class TestConfig:

    def test_add_profile(self, config):
        """Profiles can be added to the config."""
        profiles = {
            'profile1': Profile(['10.0.0.0/24']),
            'profile2': Profile(['192.168.0.0/16'])
        }
        for name, profile in profiles.items():
            config.add_profile(name, profile)
        assert config.profiles == profiles

    def test_add_profile_name_present(self, config):
        """An exception is raised if the profile name is already used."""
        config.add_profile('profile', Profile(['10.0.0.0/24']))
        with pytest.raises(KeyError):
            config.add_profile('profile', Profile(['192.168.0.0/16']))

    def test_remove_profile(self, config):
        """Profiles can be removed to the config."""
        profiles = {
            'profile1': Profile(['10.0.0.0/24']),
            'profile2': Profile(['192.168.0.0/16'])
        }
        for name, profile in profiles.items():
            config.add_profile(name, profile)
        config.remove_profile('profile1')
        assert list(config.profiles), ['profile2']

    def test_remove_profile_not_present(self, config):
        """An exception is raised if the profile name is not known."""
        with pytest.raises(KeyError):
            config.remove_profile('profile')

    def test_load_from_file(self, config, profiles_file):
        """The config is loaded from file."""
        profiles = {'profile': {'subnets': ['10.0.0.0/24'], 'auto-nets': True}}
        profiles_file.write_text(yaml.dump(profiles))
        config.load()
        profile = config.profiles['profile']
        assert profile.subnets == ['10.0.0.0/24']
        assert profile.auto_nets

    def test_load_missing_file(self, config):
        """If no config files are found, config is empty."""
        config.load()
        assert config.profiles == {}
        assert config.config == {}

    def test_load_config_options(self, config, config_file):
        """Only known config options are loaded from config file."""
        config_data = {'executable': '/usr/bin/shuttle', 'other-conf': 'no'}
        config_file.write_text(yaml.dump(config_data))
        config.load()
        assert config.config == {'executable': '/usr/bin/shuttle'}

    def test_load_profiles(self, config, profiles_file):
        """The 'profiles' config field is loaded from the config file."""
        profiles = {
            'profile1': {
                'subnets': ['10.0.0.0/24']
            },
            'profile2': {
                'subnets': ['192.168.0.0/16']
            }
        }
        profiles_file.write_text(yaml.dump(profiles))
        config.load()
        expected = {
            name: Profile.from_dict(config)
            for name, config in profiles.items()
        }
        assert config.profiles == expected

    def test_save_profiles(self, config, profiles_file):
        """Profiles are saved to file."""
        profiles = {
            'profile1': {
                'subnets': ['10.0.0.0/24'],
                'remote': 'hostname1'
            },
            'profile2': {
                'subnets': ['192.168.0.0/16'],
                'remote': 'hostname2'
            }
        }
        config.load()
        for name, conf in profiles.items():
            config.add_profile(name, Profile.from_dict(conf))
        config.save()
        config = yaml.safe_load(profiles_file.read_text())
        assert config == profiles

    def test_save_from_file(self, config, profiles_file):
        """The config is saved to file."""
        conf = {'subnets': ['10.0.0.0/24'], 'auto_nets': True}
        config.add_profile('profile', Profile.from_dict(conf))
        config.save()

        config = dedent(
            '''\
            profile:
              auto-nets: true
              subnets:
              - 10.0.0.0/24
            ''')
        content = profiles_file.read_text()
        assert content == config