import functools
import operator
import os
import sys
import unittest
import uuid

from cloudbridge.base import helpers as cb_helpers
from cloudbridge.factory import CloudProviderFactory
from cloudbridge.interfaces import CloudProvider
from cloudbridge.interfaces import InstanceState
from cloudbridge.interfaces import TestMockHelperMixin
from cloudbridge.interfaces.resources import FloatingIpState
from cloudbridge.interfaces.resources import NetworkState
from cloudbridge.interfaces.resources import SubnetState


def parse_bool(val):
    if val:
        return str(val).upper() in ['TRUE', 'YES']
    else:
        return False


def skipIfNoService(services):
    """
    A decorator for skipping tests if the provider
    does not implement a given service.
    """
    def wrap(func):
        """
        The actual wrapper
        """
        @functools.wraps(func)
        def wrapper(self, *args, **kwargs):
            provider = getattr(self, 'provider')
            if provider:
                for service in services:
                    if not provider.has_service(service):
                        self.skipTest("Skipping test because '%s' service is"
                                      " not implemented" % (service,))
            func(self, *args, **kwargs)
        return wrapper
    return wrap


def skipIfPython(op, major, minor):
    """
    A decorator for skipping tests if the python
    version doesn't match
    """
    def stringToOperator(op):
        op_map = {
            "=": operator.eq,
            "==": operator.eq,
            "<": operator.lt,
            "<=": operator.le,
            ">": operator.gt,
            ">=": operator.ge,
        }
        return op_map.get(op)

    def wrap(func):
        """
        The actual wrapper
        """
        @functools.wraps(func)
        def wrapper(self, *args, **kwargs):
            op_func = stringToOperator(op)
            if op_func(sys.version_info, (major, minor)):
                self.skipTest(
                    "Skipping test because python version {0} is {1} expected"
                    " version {2}".format(sys.version_info[:2],
                                          op, (major, minor)))
            func(self, *args, **kwargs)
        return wrapper
    return wrap


TEST_DATA_CONFIG = {
    "AWSCloudProvider": {
        # Match the ami value with entry in custom_amis.json for use with moto
        "image": cb_helpers.get_env('CB_IMAGE_AWS', 'ami-aa2ea6d0'),
        "vm_type": cb_helpers.get_env('CB_VM_TYPE_AWS', 't2.nano'),
        "placement": cb_helpers.get_env('CB_PLACEMENT_AWS', 'us-east-1a'),
        "placement_cfg_key": "aws_zone_name"
    },
    'OpenStackCloudProvider': {
        'image': cb_helpers.get_env('CB_IMAGE_OS',
                                    'c66bdfa1-62b1-43be-8964-e9ce208ac6a5'),
        "vm_type": cb_helpers.get_env('CB_VM_TYPE_OS', 'm1.tiny'),
        "placement": cb_helpers.get_env('CB_PLACEMENT_OS', 'nova'),
        "placement_cfg_key": "os_zone_name"
    },
    'GCPCloudProvider': {
        'image': cb_helpers.get_env(
            'CB_IMAGE_GCP',
            'https://www.googleapis.com/compute/v1/projects/ubuntu-os-cloud/'
            'global/images/ubuntu-1710-artful-v20180126'),
        'vm_type': cb_helpers.get_env('CB_VM_TYPE_GCP', 'f1-micro'),
        'placement': cb_helpers.get_env('GCP_ZONE_NAME', 'us-central1-a'),
        "placement_cfg_key": "gcp_zone_name"
    },
    "AzureCloudProvider": {
        "image":
            cb_helpers.get_env('CB_IMAGE_AZURE',
                               'Canonical:UbuntuServer:16.04.0-LTS:latest'),
        "vm_type": cb_helpers.get_env('CB_VM_TYPE_AZURE', 'Basic_A2'),
        "placement": cb_helpers.get_env('CB_PLACEMENT_AZURE', 'eastus'),
        "placement_cfg_key": "azure_zone_name"
    }
}


def get_provider_test_data(provider, key):
    provider_id = (provider.PROVIDER_ID if isinstance(provider, CloudProvider)
                   else provider)
    if "aws" == provider_id:
        return TEST_DATA_CONFIG.get("AWSCloudProvider").get(key)
    if "mock" == provider_id:
        return TEST_DATA_CONFIG.get("AWSCloudProvider").get(key)
    elif "openstack" == provider_id:
        return TEST_DATA_CONFIG.get("OpenStackCloudProvider").get(key)
    elif "gcp" == provider_id:
        return TEST_DATA_CONFIG.get("GCPCloudProvider").get(key)
    elif "azure" == provider_id:
        return TEST_DATA_CONFIG.get("AzureCloudProvider").get(key)
    return None


def get_or_create_default_subnet(provider):
    """
    Return the default subnet to be used for tests
    """
    return provider.networking.subnets.get_or_create_default()


def cleanup_subnet(subnet):
    if subnet:
        subnet.delete()
        subnet.wait_for([SubnetState.UNKNOWN],
                        terminal_states=[SubnetState.ERROR])


def cleanup_network(network):
    """
    Delete the supplied network, first deleting any contained subnets.
    """
    if network:
        try:
            for sn in network.subnets:
                with cb_helpers.cleanup_action(lambda: cleanup_subnet(sn)):
                    pass
        finally:
            network.delete()
            network.wait_for([NetworkState.UNKNOWN],
                             terminal_states=[NetworkState.ERROR])


def cleanup_fip(fip):
    if fip:
        fip.delete()
        fip.wait_for([FloatingIpState.UNKNOWN],
                     terminal_states=[FloatingIpState.ERROR])


def get_test_gateway(provider):
    """
    Get an internet gateway for testing.

    This includes creating a network for the gateway, which is also returned.
    """
    sn = get_or_create_default_subnet(provider)
    net = sn.network
    return net.gateways.get_or_create()


def cleanup_gateway(gateway):
    """
    Delete the supplied network and gateway.
    """
    with cb_helpers.cleanup_action(lambda: gateway.delete()):
        pass


def create_test_instance(
        provider, instance_label, subnet, launch_config=None,
        key_pair=None, vm_firewalls=None, user_data=None):

    instance = provider.compute.instances.create(
        instance_label, get_provider_test_data(provider, 'image'),
        get_provider_test_data(provider, 'vm_type'),
        subnet=subnet,
        key_pair=key_pair,
        vm_firewalls=vm_firewalls,
        launch_config=launch_config,
        user_data=user_data)

    return instance


def get_test_instance(provider, label, key_pair=None, vm_firewalls=None,
                      subnet=None, user_data=None):
    launch_config = None
    instance = create_test_instance(
        provider,
        label,
        subnet=subnet,
        key_pair=key_pair,
        vm_firewalls=vm_firewalls,
        launch_config=launch_config,
        user_data=user_data)
    instance.wait_till_ready()
    return instance


def get_test_fixtures_folder():
    return os.path.join(os.path.dirname(__file__), '../fixtures/')


def delete_instance(instance):
    if instance:
        instance.delete()
        instance.wait_for([InstanceState.DELETED, InstanceState.UNKNOWN],
                          terminal_states=[InstanceState.ERROR])


def cleanup_test_resources(instance=None, vm_firewall=None,
                           key_pair=None, network=None):
    """Clean up any combination of supplied resources."""
    with cb_helpers.cleanup_action(
            lambda: cleanup_network(network) if network else None):
        with cb_helpers.cleanup_action(
                lambda: key_pair.delete() if key_pair else None):
            with cb_helpers.cleanup_action(
                    lambda: vm_firewall.delete() if vm_firewall else None):
                delete_instance(instance)


def get_uuid():
    return str(uuid.uuid4())[:6]


class ProviderTestBase(unittest.TestCase):

    _provider = None

    def setUp(self):
        if isinstance(self.provider, TestMockHelperMixin):
            self.provider.setUpMock()

    def tearDown(self):
        if isinstance(self.provider, TestMockHelperMixin):
            self.provider.tearDownMock()
        self._provider = None

    def get_provider_wait_interval(self, provider_class):
        if issubclass(provider_class, TestMockHelperMixin):
            return 0
        else:
            return 1

    def create_provider_instance(self):
        provider_name = cb_helpers.get_env("CB_TEST_PROVIDER", "aws")
        zone_cfg_key = get_provider_test_data(provider_name,
                                              'placement_cfg_key')
        factory = CloudProviderFactory()
        provider_class = factory.get_provider_class(provider_name)
        config = {
            'default_wait_interval': self.get_provider_wait_interval(
                provider_class),
            'default_result_limit': 5,
            zone_cfg_key: get_provider_test_data(provider_name, 'placement')
        }
        return provider_class(config)

    @property
    def provider(self):
        if not self._provider:
            self._provider = self.create_provider_instance()
        return self._provider